xref: /linux/drivers/android/binder.c (revision 4bb1f7e19c4a1d6eeb52b80acff5ac63edd1b91d)
1 // SPDX-License-Identifier: GPL-2.0-only
2 /* binder.c
3  *
4  * Android IPC Subsystem
5  *
6  * Copyright (C) 2007-2008 Google, Inc.
7  */
8 
9 /*
10  * Locking overview
11  *
12  * There are 3 main spinlocks which must be acquired in the
13  * order shown:
14  *
15  * 1) proc->outer_lock : protects binder_ref
16  *    binder_proc_lock() and binder_proc_unlock() are
17  *    used to acq/rel.
18  * 2) node->lock : protects most fields of binder_node.
19  *    binder_node_lock() and binder_node_unlock() are
20  *    used to acq/rel
21  * 3) proc->inner_lock : protects the thread and node lists
22  *    (proc->threads, proc->waiting_threads, proc->nodes)
23  *    and all todo lists associated with the binder_proc
24  *    (proc->todo, thread->todo, proc->delivered_death and
25  *    node->async_todo), as well as thread->transaction_stack
26  *    binder_inner_proc_lock() and binder_inner_proc_unlock()
27  *    are used to acq/rel
28  *
29  * Any lock under procA must never be nested under any lock at the same
30  * level or below on procB.
31  *
32  * Functions that require a lock held on entry indicate which lock
33  * in the suffix of the function name:
34  *
35  * foo_olocked() : requires node->outer_lock
36  * foo_nlocked() : requires node->lock
37  * foo_ilocked() : requires proc->inner_lock
38  * foo_oilocked(): requires proc->outer_lock and proc->inner_lock
39  * foo_nilocked(): requires node->lock and proc->inner_lock
40  * ...
41  */
42 
43 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
44 
45 #include <linux/fdtable.h>
46 #include <linux/file.h>
47 #include <linux/freezer.h>
48 #include <linux/fs.h>
49 #include <linux/list.h>
50 #include <linux/miscdevice.h>
51 #include <linux/module.h>
52 #include <linux/mutex.h>
53 #include <linux/nsproxy.h>
54 #include <linux/poll.h>
55 #include <linux/debugfs.h>
56 #include <linux/rbtree.h>
57 #include <linux/sched/signal.h>
58 #include <linux/sched/mm.h>
59 #include <linux/seq_file.h>
60 #include <linux/string.h>
61 #include <linux/uaccess.h>
62 #include <linux/pid_namespace.h>
63 #include <linux/security.h>
64 #include <linux/spinlock.h>
65 #include <linux/ratelimit.h>
66 #include <linux/syscalls.h>
67 #include <linux/task_work.h>
68 #include <linux/sizes.h>
69 #include <linux/ktime.h>
70 
71 #include <kunit/visibility.h>
72 
73 #include <uapi/linux/android/binder.h>
74 
75 #include <linux/cacheflush.h>
76 
77 #include "binder_netlink.h"
78 #include "binder_internal.h"
79 #include "binder_trace.h"
80 
81 static HLIST_HEAD(binder_deferred_list);
82 static DEFINE_MUTEX(binder_deferred_lock);
83 
84 static HLIST_HEAD(binder_devices);
85 static DEFINE_SPINLOCK(binder_devices_lock);
86 
87 static HLIST_HEAD(binder_procs);
88 static DEFINE_MUTEX(binder_procs_lock);
89 
90 static HLIST_HEAD(binder_dead_nodes);
91 static DEFINE_SPINLOCK(binder_dead_nodes_lock);
92 
93 static struct dentry *binder_debugfs_dir_entry_root;
94 static struct dentry *binder_debugfs_dir_entry_proc;
95 static atomic_t binder_last_id;
96 
97 static int proc_show(struct seq_file *m, void *unused);
98 DEFINE_SHOW_ATTRIBUTE(proc);
99 
100 #define FORBIDDEN_MMAP_FLAGS                (VM_WRITE)
101 
102 enum {
103 	BINDER_DEBUG_USER_ERROR             = 1U << 0,
104 	BINDER_DEBUG_FAILED_TRANSACTION     = 1U << 1,
105 	BINDER_DEBUG_DEAD_TRANSACTION       = 1U << 2,
106 	BINDER_DEBUG_OPEN_CLOSE             = 1U << 3,
107 	BINDER_DEBUG_DEAD_BINDER            = 1U << 4,
108 	BINDER_DEBUG_DEATH_NOTIFICATION     = 1U << 5,
109 	BINDER_DEBUG_READ_WRITE             = 1U << 6,
110 	BINDER_DEBUG_USER_REFS              = 1U << 7,
111 	BINDER_DEBUG_THREADS                = 1U << 8,
112 	BINDER_DEBUG_TRANSACTION            = 1U << 9,
113 	BINDER_DEBUG_TRANSACTION_COMPLETE   = 1U << 10,
114 	BINDER_DEBUG_FREE_BUFFER            = 1U << 11,
115 	BINDER_DEBUG_INTERNAL_REFS          = 1U << 12,
116 	BINDER_DEBUG_PRIORITY_CAP           = 1U << 13,
117 	BINDER_DEBUG_SPINLOCKS              = 1U << 14,
118 };
119 static uint32_t binder_debug_mask = BINDER_DEBUG_USER_ERROR |
120 	BINDER_DEBUG_FAILED_TRANSACTION | BINDER_DEBUG_DEAD_TRANSACTION;
121 module_param_named(debug_mask, binder_debug_mask, uint, 0644);
122 
123 char *binder_devices_param = CONFIG_ANDROID_BINDER_DEVICES;
124 module_param_named(devices, binder_devices_param, charp, 0444);
125 
126 static DECLARE_WAIT_QUEUE_HEAD(binder_user_error_wait);
127 static int binder_stop_on_user_error;
128 
binder_set_stop_on_user_error(const char * val,const struct kernel_param * kp)129 static int binder_set_stop_on_user_error(const char *val,
130 					 const struct kernel_param *kp)
131 {
132 	int ret;
133 
134 	ret = param_set_int(val, kp);
135 	if (binder_stop_on_user_error < 2)
136 		wake_up(&binder_user_error_wait);
137 	return ret;
138 }
139 module_param_call(stop_on_user_error, binder_set_stop_on_user_error,
140 	param_get_int, &binder_stop_on_user_error, 0644);
141 
binder_debug(int mask,const char * format,...)142 static __printf(2, 3) void binder_debug(int mask, const char *format, ...)
143 {
144 	struct va_format vaf;
145 	va_list args;
146 
147 	if (binder_debug_mask & mask) {
148 		va_start(args, format);
149 		vaf.va = &args;
150 		vaf.fmt = format;
151 		pr_info_ratelimited("%pV", &vaf);
152 		va_end(args);
153 	}
154 }
155 
156 #define binder_txn_error(x...) \
157 	binder_debug(BINDER_DEBUG_FAILED_TRANSACTION, x)
158 
binder_user_error(const char * format,...)159 static __printf(1, 2) void binder_user_error(const char *format, ...)
160 {
161 	struct va_format vaf;
162 	va_list args;
163 
164 	if (binder_debug_mask & BINDER_DEBUG_USER_ERROR) {
165 		va_start(args, format);
166 		vaf.va = &args;
167 		vaf.fmt = format;
168 		pr_info_ratelimited("%pV", &vaf);
169 		va_end(args);
170 	}
171 
172 	if (binder_stop_on_user_error)
173 		binder_stop_on_user_error = 2;
174 }
175 
176 #define binder_set_extended_error(ee, _id, _command, _param) \
177 	do { \
178 		(ee)->id = _id; \
179 		(ee)->command = _command; \
180 		(ee)->param = _param; \
181 	} while (0)
182 
183 #define to_flat_binder_object(hdr) \
184 	container_of(hdr, struct flat_binder_object, hdr)
185 
186 #define to_binder_fd_object(hdr) container_of(hdr, struct binder_fd_object, hdr)
187 
188 #define to_binder_buffer_object(hdr) \
189 	container_of(hdr, struct binder_buffer_object, hdr)
190 
191 #define to_binder_fd_array_object(hdr) \
192 	container_of(hdr, struct binder_fd_array_object, hdr)
193 
194 static struct binder_stats binder_stats;
195 
binder_stats_deleted(enum binder_stat_types type)196 static inline void binder_stats_deleted(enum binder_stat_types type)
197 {
198 	atomic_inc(&binder_stats.obj_deleted[type]);
199 }
200 
binder_stats_created(enum binder_stat_types type)201 static inline void binder_stats_created(enum binder_stat_types type)
202 {
203 	atomic_inc(&binder_stats.obj_created[type]);
204 }
205 
206 struct binder_transaction_log_entry {
207 	int debug_id;
208 	int debug_id_done;
209 	int call_type;
210 	int from_proc;
211 	int from_thread;
212 	int target_handle;
213 	int to_proc;
214 	int to_thread;
215 	int to_node;
216 	int data_size;
217 	int offsets_size;
218 	int return_error_line;
219 	uint32_t return_error;
220 	uint32_t return_error_param;
221 	char context_name[BINDERFS_MAX_NAME + 1];
222 };
223 
224 struct binder_transaction_log {
225 	atomic_t cur;
226 	bool full;
227 	struct binder_transaction_log_entry entry[32];
228 };
229 
230 static struct binder_transaction_log binder_transaction_log;
231 static struct binder_transaction_log binder_transaction_log_failed;
232 
binder_transaction_log_add(struct binder_transaction_log * log)233 static struct binder_transaction_log_entry *binder_transaction_log_add(
234 	struct binder_transaction_log *log)
235 {
236 	struct binder_transaction_log_entry *e;
237 	unsigned int cur = atomic_inc_return(&log->cur);
238 
239 	if (cur >= ARRAY_SIZE(log->entry))
240 		log->full = true;
241 	e = &log->entry[cur % ARRAY_SIZE(log->entry)];
242 	WRITE_ONCE(e->debug_id_done, 0);
243 	/*
244 	 * write-barrier to synchronize access to e->debug_id_done.
245 	 * We make sure the initialized 0 value is seen before
246 	 * memset() other fields are zeroed by memset.
247 	 */
248 	smp_wmb();
249 	memset(e, 0, sizeof(*e));
250 	return e;
251 }
252 
253 enum binder_deferred_state {
254 	BINDER_DEFERRED_FLUSH        = 0x01,
255 	BINDER_DEFERRED_RELEASE      = 0x02,
256 };
257 
258 enum {
259 	BINDER_LOOPER_STATE_REGISTERED  = 0x01,
260 	BINDER_LOOPER_STATE_ENTERED     = 0x02,
261 	BINDER_LOOPER_STATE_EXITED      = 0x04,
262 	BINDER_LOOPER_STATE_INVALID     = 0x08,
263 	BINDER_LOOPER_STATE_WAITING     = 0x10,
264 	BINDER_LOOPER_STATE_POLL        = 0x20,
265 };
266 
267 /**
268  * binder_proc_lock() - Acquire outer lock for given binder_proc
269  * @proc:         struct binder_proc to acquire
270  *
271  * Acquires proc->outer_lock. Used to protect binder_ref
272  * structures associated with the given proc.
273  */
274 #define binder_proc_lock(proc) _binder_proc_lock(proc, __LINE__)
275 static void
_binder_proc_lock(struct binder_proc * proc,int line)276 _binder_proc_lock(struct binder_proc *proc, int line)
277 	__acquires(&proc->outer_lock)
278 {
279 	binder_debug(BINDER_DEBUG_SPINLOCKS,
280 		     "%s: line=%d\n", __func__, line);
281 	spin_lock(&proc->outer_lock);
282 }
283 
284 /**
285  * binder_proc_unlock() - Release outer lock for given binder_proc
286  * @proc:                struct binder_proc to acquire
287  *
288  * Release lock acquired via binder_proc_lock()
289  */
290 #define binder_proc_unlock(proc) _binder_proc_unlock(proc, __LINE__)
291 static void
_binder_proc_unlock(struct binder_proc * proc,int line)292 _binder_proc_unlock(struct binder_proc *proc, int line)
293 	__releases(&proc->outer_lock)
294 {
295 	binder_debug(BINDER_DEBUG_SPINLOCKS,
296 		     "%s: line=%d\n", __func__, line);
297 	spin_unlock(&proc->outer_lock);
298 }
299 
300 /**
301  * binder_inner_proc_lock() - Acquire inner lock for given binder_proc
302  * @proc:         struct binder_proc to acquire
303  *
304  * Acquires proc->inner_lock. Used to protect todo lists
305  */
306 #define binder_inner_proc_lock(proc) _binder_inner_proc_lock(proc, __LINE__)
307 static void
_binder_inner_proc_lock(struct binder_proc * proc,int line)308 _binder_inner_proc_lock(struct binder_proc *proc, int line)
309 	__acquires(&proc->inner_lock)
310 {
311 	binder_debug(BINDER_DEBUG_SPINLOCKS,
312 		     "%s: line=%d\n", __func__, line);
313 	spin_lock(&proc->inner_lock);
314 }
315 
316 /**
317  * binder_inner_proc_unlock() - Release inner lock for given binder_proc
318  * @proc:         struct binder_proc to acquire
319  *
320  * Release lock acquired via binder_inner_proc_lock()
321  */
322 #define binder_inner_proc_unlock(proc) _binder_inner_proc_unlock(proc, __LINE__)
323 static void
_binder_inner_proc_unlock(struct binder_proc * proc,int line)324 _binder_inner_proc_unlock(struct binder_proc *proc, int line)
325 	__releases(&proc->inner_lock)
326 {
327 	binder_debug(BINDER_DEBUG_SPINLOCKS,
328 		     "%s: line=%d\n", __func__, line);
329 	spin_unlock(&proc->inner_lock);
330 }
331 
332 /**
333  * binder_node_lock() - Acquire spinlock for given binder_node
334  * @node:         struct binder_node to acquire
335  *
336  * Acquires node->lock. Used to protect binder_node fields
337  */
338 #define binder_node_lock(node) _binder_node_lock(node, __LINE__)
339 static void
_binder_node_lock(struct binder_node * node,int line)340 _binder_node_lock(struct binder_node *node, int line)
341 	__acquires(&node->lock)
342 {
343 	binder_debug(BINDER_DEBUG_SPINLOCKS,
344 		     "%s: line=%d\n", __func__, line);
345 	spin_lock(&node->lock);
346 }
347 
348 /**
349  * binder_node_unlock() - Release spinlock for given binder_proc
350  * @node:         struct binder_node to acquire
351  *
352  * Release lock acquired via binder_node_lock()
353  */
354 #define binder_node_unlock(node) _binder_node_unlock(node, __LINE__)
355 static void
_binder_node_unlock(struct binder_node * node,int line)356 _binder_node_unlock(struct binder_node *node, int line)
357 	__releases(&node->lock)
358 {
359 	binder_debug(BINDER_DEBUG_SPINLOCKS,
360 		     "%s: line=%d\n", __func__, line);
361 	spin_unlock(&node->lock);
362 }
363 
364 /**
365  * binder_node_inner_lock() - Acquire node and inner locks
366  * @node:         struct binder_node to acquire
367  *
368  * Acquires node->lock. If node->proc also acquires
369  * proc->inner_lock. Used to protect binder_node fields
370  */
371 #define binder_node_inner_lock(node) _binder_node_inner_lock(node, __LINE__)
372 static void
_binder_node_inner_lock(struct binder_node * node,int line)373 _binder_node_inner_lock(struct binder_node *node, int line)
374 	__acquires(&node->lock) __acquires(&node->proc->inner_lock)
375 {
376 	binder_debug(BINDER_DEBUG_SPINLOCKS,
377 		     "%s: line=%d\n", __func__, line);
378 	spin_lock(&node->lock);
379 	if (node->proc)
380 		binder_inner_proc_lock(node->proc);
381 	else
382 		/* annotation for sparse */
383 		__acquire(&node->proc->inner_lock);
384 }
385 
386 /**
387  * binder_node_inner_unlock() - Release node and inner locks
388  * @node:         struct binder_node to acquire
389  *
390  * Release lock acquired via binder_node_lock()
391  */
392 #define binder_node_inner_unlock(node) _binder_node_inner_unlock(node, __LINE__)
393 static void
_binder_node_inner_unlock(struct binder_node * node,int line)394 _binder_node_inner_unlock(struct binder_node *node, int line)
395 	__releases(&node->lock) __releases(&node->proc->inner_lock)
396 {
397 	struct binder_proc *proc = node->proc;
398 
399 	binder_debug(BINDER_DEBUG_SPINLOCKS,
400 		     "%s: line=%d\n", __func__, line);
401 	if (proc)
402 		binder_inner_proc_unlock(proc);
403 	else
404 		/* annotation for sparse */
405 		__release(&node->proc->inner_lock);
406 	spin_unlock(&node->lock);
407 }
408 
binder_worklist_empty_ilocked(struct list_head * list)409 static bool binder_worklist_empty_ilocked(struct list_head *list)
410 {
411 	return list_empty(list);
412 }
413 
414 /**
415  * binder_worklist_empty() - Check if no items on the work list
416  * @proc:       binder_proc associated with list
417  * @list:	list to check
418  *
419  * Return: true if there are no items on list, else false
420  */
binder_worklist_empty(struct binder_proc * proc,struct list_head * list)421 static bool binder_worklist_empty(struct binder_proc *proc,
422 				  struct list_head *list)
423 {
424 	bool ret;
425 
426 	binder_inner_proc_lock(proc);
427 	ret = binder_worklist_empty_ilocked(list);
428 	binder_inner_proc_unlock(proc);
429 	return ret;
430 }
431 
432 /**
433  * binder_enqueue_work_ilocked() - Add an item to the work list
434  * @work:         struct binder_work to add to list
435  * @target_list:  list to add work to
436  *
437  * Adds the work to the specified list. Asserts that work
438  * is not already on a list.
439  *
440  * Requires the proc->inner_lock to be held.
441  */
442 static void
binder_enqueue_work_ilocked(struct binder_work * work,struct list_head * target_list)443 binder_enqueue_work_ilocked(struct binder_work *work,
444 			   struct list_head *target_list)
445 {
446 	BUG_ON(target_list == NULL);
447 	BUG_ON(work->entry.next && !list_empty(&work->entry));
448 	list_add_tail(&work->entry, target_list);
449 }
450 
451 /**
452  * binder_enqueue_deferred_thread_work_ilocked() - Add deferred thread work
453  * @thread:       thread to queue work to
454  * @work:         struct binder_work to add to list
455  *
456  * Adds the work to the todo list of the thread. Doesn't set the process_todo
457  * flag, which means that (if it wasn't already set) the thread will go to
458  * sleep without handling this work when it calls read.
459  *
460  * Requires the proc->inner_lock to be held.
461  */
462 static void
binder_enqueue_deferred_thread_work_ilocked(struct binder_thread * thread,struct binder_work * work)463 binder_enqueue_deferred_thread_work_ilocked(struct binder_thread *thread,
464 					    struct binder_work *work)
465 {
466 	WARN_ON(!list_empty(&thread->waiting_thread_node));
467 	binder_enqueue_work_ilocked(work, &thread->todo);
468 }
469 
470 /**
471  * binder_enqueue_thread_work_ilocked() - Add an item to the thread work list
472  * @thread:       thread to queue work to
473  * @work:         struct binder_work to add to list
474  *
475  * Adds the work to the todo list of the thread, and enables processing
476  * of the todo queue.
477  *
478  * Requires the proc->inner_lock to be held.
479  */
480 static void
binder_enqueue_thread_work_ilocked(struct binder_thread * thread,struct binder_work * work)481 binder_enqueue_thread_work_ilocked(struct binder_thread *thread,
482 				   struct binder_work *work)
483 {
484 	WARN_ON(!list_empty(&thread->waiting_thread_node));
485 	binder_enqueue_work_ilocked(work, &thread->todo);
486 
487 	/* (e)poll-based threads require an explicit wakeup signal when
488 	 * queuing their own work; they rely on these events to consume
489 	 * messages without I/O block. Without it, threads risk waiting
490 	 * indefinitely without handling the work.
491 	 */
492 	if (thread->looper & BINDER_LOOPER_STATE_POLL &&
493 	    thread->pid == current->pid && !thread->process_todo)
494 		wake_up_interruptible_sync(&thread->wait);
495 
496 	thread->process_todo = true;
497 }
498 
499 /**
500  * binder_enqueue_thread_work() - Add an item to the thread work list
501  * @thread:       thread to queue work to
502  * @work:         struct binder_work to add to list
503  *
504  * Adds the work to the todo list of the thread, and enables processing
505  * of the todo queue.
506  */
507 static void
binder_enqueue_thread_work(struct binder_thread * thread,struct binder_work * work)508 binder_enqueue_thread_work(struct binder_thread *thread,
509 			   struct binder_work *work)
510 {
511 	binder_inner_proc_lock(thread->proc);
512 	binder_enqueue_thread_work_ilocked(thread, work);
513 	binder_inner_proc_unlock(thread->proc);
514 }
515 
516 static void
binder_dequeue_work_ilocked(struct binder_work * work)517 binder_dequeue_work_ilocked(struct binder_work *work)
518 {
519 	list_del_init(&work->entry);
520 }
521 
522 /**
523  * binder_dequeue_work() - Removes an item from the work list
524  * @proc:         binder_proc associated with list
525  * @work:         struct binder_work to remove from list
526  *
527  * Removes the specified work item from whatever list it is on.
528  * Can safely be called if work is not on any list.
529  */
530 static void
binder_dequeue_work(struct binder_proc * proc,struct binder_work * work)531 binder_dequeue_work(struct binder_proc *proc, struct binder_work *work)
532 {
533 	binder_inner_proc_lock(proc);
534 	binder_dequeue_work_ilocked(work);
535 	binder_inner_proc_unlock(proc);
536 }
537 
binder_dequeue_work_head_ilocked(struct list_head * list)538 static struct binder_work *binder_dequeue_work_head_ilocked(
539 					struct list_head *list)
540 {
541 	struct binder_work *w;
542 
543 	w = list_first_entry_or_null(list, struct binder_work, entry);
544 	if (w)
545 		list_del_init(&w->entry);
546 	return w;
547 }
548 
549 static void
550 binder_defer_work(struct binder_proc *proc, enum binder_deferred_state defer);
551 static void binder_free_thread(struct binder_thread *thread);
552 static void binder_free_proc(struct binder_proc *proc);
553 static void binder_inc_node_tmpref_ilocked(struct binder_node *node);
554 
binder_has_work_ilocked(struct binder_thread * thread,bool do_proc_work)555 static bool binder_has_work_ilocked(struct binder_thread *thread,
556 				    bool do_proc_work)
557 {
558 	return thread->process_todo ||
559 		thread->looper_need_return ||
560 		(do_proc_work &&
561 		 !binder_worklist_empty_ilocked(&thread->proc->todo));
562 }
563 
binder_has_work(struct binder_thread * thread,bool do_proc_work)564 static bool binder_has_work(struct binder_thread *thread, bool do_proc_work)
565 {
566 	bool has_work;
567 
568 	binder_inner_proc_lock(thread->proc);
569 	has_work = binder_has_work_ilocked(thread, do_proc_work);
570 	binder_inner_proc_unlock(thread->proc);
571 
572 	return has_work;
573 }
574 
binder_available_for_proc_work_ilocked(struct binder_thread * thread)575 static bool binder_available_for_proc_work_ilocked(struct binder_thread *thread)
576 {
577 	return !thread->transaction_stack &&
578 		binder_worklist_empty_ilocked(&thread->todo);
579 }
580 
binder_wakeup_poll_threads_ilocked(struct binder_proc * proc,bool sync)581 static void binder_wakeup_poll_threads_ilocked(struct binder_proc *proc,
582 					       bool sync)
583 {
584 	struct rb_node *n;
585 	struct binder_thread *thread;
586 
587 	for (n = rb_first(&proc->threads); n != NULL; n = rb_next(n)) {
588 		thread = rb_entry(n, struct binder_thread, rb_node);
589 		if (thread->looper & BINDER_LOOPER_STATE_POLL &&
590 		    binder_available_for_proc_work_ilocked(thread)) {
591 			if (sync)
592 				wake_up_interruptible_sync(&thread->wait);
593 			else
594 				wake_up_interruptible(&thread->wait);
595 		}
596 	}
597 }
598 
599 /**
600  * binder_select_thread_ilocked() - selects a thread for doing proc work.
601  * @proc:	process to select a thread from
602  *
603  * Note that calling this function moves the thread off the waiting_threads
604  * list, so it can only be woken up by the caller of this function, or a
605  * signal. Therefore, callers *should* always wake up the thread this function
606  * returns.
607  *
608  * Return:	If there's a thread currently waiting for process work,
609  *		returns that thread. Otherwise returns NULL.
610  */
611 static struct binder_thread *
binder_select_thread_ilocked(struct binder_proc * proc)612 binder_select_thread_ilocked(struct binder_proc *proc)
613 {
614 	struct binder_thread *thread;
615 
616 	assert_spin_locked(&proc->inner_lock);
617 	thread = list_first_entry_or_null(&proc->waiting_threads,
618 					  struct binder_thread,
619 					  waiting_thread_node);
620 
621 	if (thread)
622 		list_del_init(&thread->waiting_thread_node);
623 
624 	return thread;
625 }
626 
627 /**
628  * binder_wakeup_thread_ilocked() - wakes up a thread for doing proc work.
629  * @proc:	process to wake up a thread in
630  * @thread:	specific thread to wake-up (may be NULL)
631  * @sync:	whether to do a synchronous wake-up
632  *
633  * This function wakes up a thread in the @proc process.
634  * The caller may provide a specific thread to wake-up in
635  * the @thread parameter. If @thread is NULL, this function
636  * will wake up threads that have called poll().
637  *
638  * Note that for this function to work as expected, callers
639  * should first call binder_select_thread() to find a thread
640  * to handle the work (if they don't have a thread already),
641  * and pass the result into the @thread parameter.
642  */
binder_wakeup_thread_ilocked(struct binder_proc * proc,struct binder_thread * thread,bool sync)643 static void binder_wakeup_thread_ilocked(struct binder_proc *proc,
644 					 struct binder_thread *thread,
645 					 bool sync)
646 {
647 	assert_spin_locked(&proc->inner_lock);
648 
649 	if (thread) {
650 		if (sync)
651 			wake_up_interruptible_sync(&thread->wait);
652 		else
653 			wake_up_interruptible(&thread->wait);
654 		return;
655 	}
656 
657 	/* Didn't find a thread waiting for proc work; this can happen
658 	 * in two scenarios:
659 	 * 1. All threads are busy handling transactions
660 	 *    In that case, one of those threads should call back into
661 	 *    the kernel driver soon and pick up this work.
662 	 * 2. Threads are using the (e)poll interface, in which case
663 	 *    they may be blocked on the waitqueue without having been
664 	 *    added to waiting_threads. For this case, we just iterate
665 	 *    over all threads not handling transaction work, and
666 	 *    wake them all up. We wake all because we don't know whether
667 	 *    a thread that called into (e)poll is handling non-binder
668 	 *    work currently.
669 	 */
670 	binder_wakeup_poll_threads_ilocked(proc, sync);
671 }
672 
binder_wakeup_proc_ilocked(struct binder_proc * proc)673 static void binder_wakeup_proc_ilocked(struct binder_proc *proc)
674 {
675 	struct binder_thread *thread = binder_select_thread_ilocked(proc);
676 
677 	binder_wakeup_thread_ilocked(proc, thread, /* sync = */false);
678 }
679 
binder_set_nice(long nice)680 static void binder_set_nice(long nice)
681 {
682 	long min_nice;
683 
684 	if (can_nice(current, nice)) {
685 		set_user_nice(current, nice);
686 		return;
687 	}
688 	min_nice = rlimit_to_nice(rlimit(RLIMIT_NICE));
689 	binder_debug(BINDER_DEBUG_PRIORITY_CAP,
690 		     "%d: nice value %ld not allowed use %ld instead\n",
691 		      current->pid, nice, min_nice);
692 	set_user_nice(current, min_nice);
693 	if (min_nice <= MAX_NICE)
694 		return;
695 	binder_user_error("%d RLIMIT_NICE not set\n", current->pid);
696 }
697 
binder_get_node_ilocked(struct binder_proc * proc,binder_uintptr_t ptr)698 static struct binder_node *binder_get_node_ilocked(struct binder_proc *proc,
699 						   binder_uintptr_t ptr)
700 {
701 	struct rb_node *n = proc->nodes.rb_node;
702 	struct binder_node *node;
703 
704 	assert_spin_locked(&proc->inner_lock);
705 
706 	while (n) {
707 		node = rb_entry(n, struct binder_node, rb_node);
708 
709 		if (ptr < node->ptr)
710 			n = n->rb_left;
711 		else if (ptr > node->ptr)
712 			n = n->rb_right;
713 		else {
714 			/*
715 			 * take an implicit weak reference
716 			 * to ensure node stays alive until
717 			 * call to binder_put_node()
718 			 */
719 			binder_inc_node_tmpref_ilocked(node);
720 			return node;
721 		}
722 	}
723 	return NULL;
724 }
725 
binder_get_node(struct binder_proc * proc,binder_uintptr_t ptr)726 static struct binder_node *binder_get_node(struct binder_proc *proc,
727 					   binder_uintptr_t ptr)
728 {
729 	struct binder_node *node;
730 
731 	binder_inner_proc_lock(proc);
732 	node = binder_get_node_ilocked(proc, ptr);
733 	binder_inner_proc_unlock(proc);
734 	return node;
735 }
736 
binder_init_node_ilocked(struct binder_proc * proc,struct binder_node * new_node,struct flat_binder_object * fp)737 static struct binder_node *binder_init_node_ilocked(
738 						struct binder_proc *proc,
739 						struct binder_node *new_node,
740 						struct flat_binder_object *fp)
741 {
742 	struct rb_node **p = &proc->nodes.rb_node;
743 	struct rb_node *parent = NULL;
744 	struct binder_node *node;
745 	binder_uintptr_t ptr = fp ? fp->binder : 0;
746 	binder_uintptr_t cookie = fp ? fp->cookie : 0;
747 	__u32 flags = fp ? fp->flags : 0;
748 
749 	assert_spin_locked(&proc->inner_lock);
750 
751 	while (*p) {
752 
753 		parent = *p;
754 		node = rb_entry(parent, struct binder_node, rb_node);
755 
756 		if (ptr < node->ptr)
757 			p = &(*p)->rb_left;
758 		else if (ptr > node->ptr)
759 			p = &(*p)->rb_right;
760 		else {
761 			/*
762 			 * A matching node is already in
763 			 * the rb tree. Abandon the init
764 			 * and return it.
765 			 */
766 			binder_inc_node_tmpref_ilocked(node);
767 			return node;
768 		}
769 	}
770 	node = new_node;
771 	binder_stats_created(BINDER_STAT_NODE);
772 	node->tmp_refs++;
773 	rb_link_node(&node->rb_node, parent, p);
774 	rb_insert_color(&node->rb_node, &proc->nodes);
775 	node->debug_id = atomic_inc_return(&binder_last_id);
776 	node->proc = proc;
777 	node->ptr = ptr;
778 	node->cookie = cookie;
779 	node->work.type = BINDER_WORK_NODE;
780 	node->min_priority = flags & FLAT_BINDER_FLAG_PRIORITY_MASK;
781 	node->accept_fds = !!(flags & FLAT_BINDER_FLAG_ACCEPTS_FDS);
782 	node->txn_security_ctx = !!(flags & FLAT_BINDER_FLAG_TXN_SECURITY_CTX);
783 	spin_lock_init(&node->lock);
784 	INIT_LIST_HEAD(&node->work.entry);
785 	INIT_LIST_HEAD(&node->async_todo);
786 	binder_debug(BINDER_DEBUG_INTERNAL_REFS,
787 		     "%d:%d node %d u%016llx c%016llx created\n",
788 		     proc->pid, current->pid, node->debug_id,
789 		     (u64)node->ptr, (u64)node->cookie);
790 
791 	return node;
792 }
793 
binder_new_node(struct binder_proc * proc,struct flat_binder_object * fp)794 static struct binder_node *binder_new_node(struct binder_proc *proc,
795 					   struct flat_binder_object *fp)
796 {
797 	struct binder_node *node;
798 	struct binder_node *new_node = kzalloc(sizeof(*node), GFP_KERNEL);
799 
800 	if (!new_node)
801 		return NULL;
802 	binder_inner_proc_lock(proc);
803 	node = binder_init_node_ilocked(proc, new_node, fp);
804 	binder_inner_proc_unlock(proc);
805 	if (node != new_node)
806 		/*
807 		 * The node was already added by another thread
808 		 */
809 		kfree(new_node);
810 
811 	return node;
812 }
813 
binder_free_node(struct binder_node * node)814 static void binder_free_node(struct binder_node *node)
815 {
816 	kfree(node);
817 	binder_stats_deleted(BINDER_STAT_NODE);
818 }
819 
binder_inc_node_nilocked(struct binder_node * node,int strong,int internal,struct list_head * target_list)820 static int binder_inc_node_nilocked(struct binder_node *node, int strong,
821 				    int internal,
822 				    struct list_head *target_list)
823 {
824 	struct binder_proc *proc = node->proc;
825 
826 	assert_spin_locked(&node->lock);
827 	if (proc)
828 		assert_spin_locked(&proc->inner_lock);
829 	if (strong) {
830 		if (internal) {
831 			if (target_list == NULL &&
832 			    node->internal_strong_refs == 0 &&
833 			    !(node->proc &&
834 			      node == node->proc->context->binder_context_mgr_node &&
835 			      node->has_strong_ref)) {
836 				pr_err("invalid inc strong node for %d\n",
837 					node->debug_id);
838 				return -EINVAL;
839 			}
840 			node->internal_strong_refs++;
841 		} else
842 			node->local_strong_refs++;
843 		if (!node->has_strong_ref && target_list) {
844 			struct binder_thread *thread = container_of(target_list,
845 						    struct binder_thread, todo);
846 			binder_dequeue_work_ilocked(&node->work);
847 			BUG_ON(&thread->todo != target_list);
848 			binder_enqueue_deferred_thread_work_ilocked(thread,
849 								   &node->work);
850 		}
851 	} else {
852 		if (!internal)
853 			node->local_weak_refs++;
854 		if (!node->has_weak_ref && target_list && list_empty(&node->work.entry))
855 			binder_enqueue_work_ilocked(&node->work, target_list);
856 	}
857 	return 0;
858 }
859 
binder_inc_node(struct binder_node * node,int strong,int internal,struct list_head * target_list)860 static int binder_inc_node(struct binder_node *node, int strong, int internal,
861 			   struct list_head *target_list)
862 {
863 	int ret;
864 
865 	binder_node_inner_lock(node);
866 	ret = binder_inc_node_nilocked(node, strong, internal, target_list);
867 	binder_node_inner_unlock(node);
868 
869 	return ret;
870 }
871 
binder_dec_node_nilocked(struct binder_node * node,int strong,int internal)872 static bool binder_dec_node_nilocked(struct binder_node *node,
873 				     int strong, int internal)
874 {
875 	struct binder_proc *proc = node->proc;
876 
877 	assert_spin_locked(&node->lock);
878 	if (proc)
879 		assert_spin_locked(&proc->inner_lock);
880 	if (strong) {
881 		if (internal)
882 			node->internal_strong_refs--;
883 		else
884 			node->local_strong_refs--;
885 		if (node->local_strong_refs || node->internal_strong_refs)
886 			return false;
887 	} else {
888 		if (!internal)
889 			node->local_weak_refs--;
890 		if (node->local_weak_refs || node->tmp_refs ||
891 				!hlist_empty(&node->refs))
892 			return false;
893 	}
894 
895 	if (proc && (node->has_strong_ref || node->has_weak_ref)) {
896 		if (list_empty(&node->work.entry)) {
897 			binder_enqueue_work_ilocked(&node->work, &proc->todo);
898 			binder_wakeup_proc_ilocked(proc);
899 		}
900 	} else {
901 		if (hlist_empty(&node->refs) && !node->local_strong_refs &&
902 		    !node->local_weak_refs && !node->tmp_refs) {
903 			if (proc) {
904 				binder_dequeue_work_ilocked(&node->work);
905 				rb_erase(&node->rb_node, &proc->nodes);
906 				binder_debug(BINDER_DEBUG_INTERNAL_REFS,
907 					     "refless node %d deleted\n",
908 					     node->debug_id);
909 			} else {
910 				BUG_ON(!list_empty(&node->work.entry));
911 				spin_lock(&binder_dead_nodes_lock);
912 				/*
913 				 * tmp_refs could have changed so
914 				 * check it again
915 				 */
916 				if (node->tmp_refs) {
917 					spin_unlock(&binder_dead_nodes_lock);
918 					return false;
919 				}
920 				hlist_del(&node->dead_node);
921 				spin_unlock(&binder_dead_nodes_lock);
922 				binder_debug(BINDER_DEBUG_INTERNAL_REFS,
923 					     "dead node %d deleted\n",
924 					     node->debug_id);
925 			}
926 			return true;
927 		}
928 	}
929 	return false;
930 }
931 
binder_dec_node(struct binder_node * node,int strong,int internal)932 static void binder_dec_node(struct binder_node *node, int strong, int internal)
933 {
934 	bool free_node;
935 
936 	binder_node_inner_lock(node);
937 	free_node = binder_dec_node_nilocked(node, strong, internal);
938 	binder_node_inner_unlock(node);
939 	if (free_node)
940 		binder_free_node(node);
941 }
942 
binder_inc_node_tmpref_ilocked(struct binder_node * node)943 static void binder_inc_node_tmpref_ilocked(struct binder_node *node)
944 {
945 	/*
946 	 * No call to binder_inc_node() is needed since we
947 	 * don't need to inform userspace of any changes to
948 	 * tmp_refs
949 	 */
950 	node->tmp_refs++;
951 }
952 
953 /**
954  * binder_inc_node_tmpref() - take a temporary reference on node
955  * @node:	node to reference
956  *
957  * Take reference on node to prevent the node from being freed
958  * while referenced only by a local variable. The inner lock is
959  * needed to serialize with the node work on the queue (which
960  * isn't needed after the node is dead). If the node is dead
961  * (node->proc is NULL), use binder_dead_nodes_lock to protect
962  * node->tmp_refs against dead-node-only cases where the node
963  * lock cannot be acquired (eg traversing the dead node list to
964  * print nodes)
965  */
binder_inc_node_tmpref(struct binder_node * node)966 static void binder_inc_node_tmpref(struct binder_node *node)
967 {
968 	binder_node_lock(node);
969 	if (node->proc)
970 		binder_inner_proc_lock(node->proc);
971 	else
972 		spin_lock(&binder_dead_nodes_lock);
973 	binder_inc_node_tmpref_ilocked(node);
974 	if (node->proc)
975 		binder_inner_proc_unlock(node->proc);
976 	else
977 		spin_unlock(&binder_dead_nodes_lock);
978 	binder_node_unlock(node);
979 }
980 
981 /**
982  * binder_dec_node_tmpref() - remove a temporary reference on node
983  * @node:	node to reference
984  *
985  * Release temporary reference on node taken via binder_inc_node_tmpref()
986  */
binder_dec_node_tmpref(struct binder_node * node)987 static void binder_dec_node_tmpref(struct binder_node *node)
988 {
989 	bool free_node;
990 
991 	binder_node_inner_lock(node);
992 	if (!node->proc)
993 		spin_lock(&binder_dead_nodes_lock);
994 	else
995 		__acquire(&binder_dead_nodes_lock);
996 	node->tmp_refs--;
997 	BUG_ON(node->tmp_refs < 0);
998 	if (!node->proc)
999 		spin_unlock(&binder_dead_nodes_lock);
1000 	else
1001 		__release(&binder_dead_nodes_lock);
1002 	/*
1003 	 * Call binder_dec_node() to check if all refcounts are 0
1004 	 * and cleanup is needed. Calling with strong=0 and internal=1
1005 	 * causes no actual reference to be released in binder_dec_node().
1006 	 * If that changes, a change is needed here too.
1007 	 */
1008 	free_node = binder_dec_node_nilocked(node, 0, 1);
1009 	binder_node_inner_unlock(node);
1010 	if (free_node)
1011 		binder_free_node(node);
1012 }
1013 
binder_put_node(struct binder_node * node)1014 static void binder_put_node(struct binder_node *node)
1015 {
1016 	binder_dec_node_tmpref(node);
1017 }
1018 
binder_get_ref_olocked(struct binder_proc * proc,u32 desc,bool need_strong_ref)1019 static struct binder_ref *binder_get_ref_olocked(struct binder_proc *proc,
1020 						 u32 desc, bool need_strong_ref)
1021 {
1022 	struct rb_node *n = proc->refs_by_desc.rb_node;
1023 	struct binder_ref *ref;
1024 
1025 	while (n) {
1026 		ref = rb_entry(n, struct binder_ref, rb_node_desc);
1027 
1028 		if (desc < ref->data.desc) {
1029 			n = n->rb_left;
1030 		} else if (desc > ref->data.desc) {
1031 			n = n->rb_right;
1032 		} else if (need_strong_ref && !ref->data.strong) {
1033 			binder_user_error("tried to use weak ref as strong ref\n");
1034 			return NULL;
1035 		} else {
1036 			return ref;
1037 		}
1038 	}
1039 	return NULL;
1040 }
1041 
1042 /* Find the smallest unused descriptor the "slow way" */
slow_desc_lookup_olocked(struct binder_proc * proc,u32 offset)1043 static u32 slow_desc_lookup_olocked(struct binder_proc *proc, u32 offset)
1044 {
1045 	struct binder_ref *ref;
1046 	struct rb_node *n;
1047 	u32 desc;
1048 
1049 	desc = offset;
1050 	for (n = rb_first(&proc->refs_by_desc); n; n = rb_next(n)) {
1051 		ref = rb_entry(n, struct binder_ref, rb_node_desc);
1052 		if (ref->data.desc > desc)
1053 			break;
1054 		desc = ref->data.desc + 1;
1055 	}
1056 
1057 	return desc;
1058 }
1059 
1060 /*
1061  * Find an available reference descriptor ID. The proc->outer_lock might
1062  * be released in the process, in which case -EAGAIN is returned and the
1063  * @desc should be considered invalid.
1064  */
get_ref_desc_olocked(struct binder_proc * proc,struct binder_node * node,u32 * desc)1065 static int get_ref_desc_olocked(struct binder_proc *proc,
1066 				struct binder_node *node,
1067 				u32 *desc)
1068 {
1069 	struct dbitmap *dmap = &proc->dmap;
1070 	unsigned int nbits, offset;
1071 	unsigned long *new, bit;
1072 
1073 	/* 0 is reserved for the context manager */
1074 	offset = (node == proc->context->binder_context_mgr_node) ? 0 : 1;
1075 
1076 	if (!dbitmap_enabled(dmap)) {
1077 		*desc = slow_desc_lookup_olocked(proc, offset);
1078 		return 0;
1079 	}
1080 
1081 	if (dbitmap_acquire_next_zero_bit(dmap, offset, &bit) == 0) {
1082 		*desc = bit;
1083 		return 0;
1084 	}
1085 
1086 	/*
1087 	 * The dbitmap is full and needs to grow. The proc->outer_lock
1088 	 * is briefly released to allocate the new bitmap safely.
1089 	 */
1090 	nbits = dbitmap_grow_nbits(dmap);
1091 	binder_proc_unlock(proc);
1092 	new = bitmap_zalloc(nbits, GFP_KERNEL);
1093 	binder_proc_lock(proc);
1094 	dbitmap_grow(dmap, new, nbits);
1095 
1096 	return -EAGAIN;
1097 }
1098 
1099 /**
1100  * binder_get_ref_for_node_olocked() - get the ref associated with given node
1101  * @proc:	binder_proc that owns the ref
1102  * @node:	binder_node of target
1103  * @new_ref:	newly allocated binder_ref to be initialized or %NULL
1104  *
1105  * Look up the ref for the given node and return it if it exists
1106  *
1107  * If it doesn't exist and the caller provides a newly allocated
1108  * ref, initialize the fields of the newly allocated ref and insert
1109  * into the given proc rb_trees and node refs list.
1110  *
1111  * Return:	the ref for node. It is possible that another thread
1112  *		allocated/initialized the ref first in which case the
1113  *		returned ref would be different than the passed-in
1114  *		new_ref. new_ref must be kfree'd by the caller in
1115  *		this case.
1116  */
binder_get_ref_for_node_olocked(struct binder_proc * proc,struct binder_node * node,struct binder_ref * new_ref)1117 static struct binder_ref *binder_get_ref_for_node_olocked(
1118 					struct binder_proc *proc,
1119 					struct binder_node *node,
1120 					struct binder_ref *new_ref)
1121 {
1122 	struct binder_ref *ref;
1123 	struct rb_node *parent;
1124 	struct rb_node **p;
1125 	u32 desc;
1126 
1127 retry:
1128 	p = &proc->refs_by_node.rb_node;
1129 	parent = NULL;
1130 	while (*p) {
1131 		parent = *p;
1132 		ref = rb_entry(parent, struct binder_ref, rb_node_node);
1133 
1134 		if (node < ref->node)
1135 			p = &(*p)->rb_left;
1136 		else if (node > ref->node)
1137 			p = &(*p)->rb_right;
1138 		else
1139 			return ref;
1140 	}
1141 	if (!new_ref)
1142 		return NULL;
1143 
1144 	/* might release the proc->outer_lock */
1145 	if (get_ref_desc_olocked(proc, node, &desc) == -EAGAIN)
1146 		goto retry;
1147 
1148 	binder_stats_created(BINDER_STAT_REF);
1149 	new_ref->data.debug_id = atomic_inc_return(&binder_last_id);
1150 	new_ref->proc = proc;
1151 	new_ref->node = node;
1152 	rb_link_node(&new_ref->rb_node_node, parent, p);
1153 	rb_insert_color(&new_ref->rb_node_node, &proc->refs_by_node);
1154 
1155 	new_ref->data.desc = desc;
1156 	p = &proc->refs_by_desc.rb_node;
1157 	while (*p) {
1158 		parent = *p;
1159 		ref = rb_entry(parent, struct binder_ref, rb_node_desc);
1160 
1161 		if (new_ref->data.desc < ref->data.desc)
1162 			p = &(*p)->rb_left;
1163 		else if (new_ref->data.desc > ref->data.desc)
1164 			p = &(*p)->rb_right;
1165 		else
1166 			BUG();
1167 	}
1168 	rb_link_node(&new_ref->rb_node_desc, parent, p);
1169 	rb_insert_color(&new_ref->rb_node_desc, &proc->refs_by_desc);
1170 
1171 	binder_node_lock(node);
1172 	hlist_add_head(&new_ref->node_entry, &node->refs);
1173 
1174 	binder_debug(BINDER_DEBUG_INTERNAL_REFS,
1175 		     "%d new ref %d desc %d for node %d\n",
1176 		      proc->pid, new_ref->data.debug_id, new_ref->data.desc,
1177 		      node->debug_id);
1178 	binder_node_unlock(node);
1179 	return new_ref;
1180 }
1181 
binder_cleanup_ref_olocked(struct binder_ref * ref)1182 static void binder_cleanup_ref_olocked(struct binder_ref *ref)
1183 {
1184 	struct dbitmap *dmap = &ref->proc->dmap;
1185 	bool delete_node = false;
1186 
1187 	binder_debug(BINDER_DEBUG_INTERNAL_REFS,
1188 		     "%d delete ref %d desc %d for node %d\n",
1189 		      ref->proc->pid, ref->data.debug_id, ref->data.desc,
1190 		      ref->node->debug_id);
1191 
1192 	if (dbitmap_enabled(dmap))
1193 		dbitmap_clear_bit(dmap, ref->data.desc);
1194 	rb_erase(&ref->rb_node_desc, &ref->proc->refs_by_desc);
1195 	rb_erase(&ref->rb_node_node, &ref->proc->refs_by_node);
1196 
1197 	binder_node_inner_lock(ref->node);
1198 	if (ref->data.strong)
1199 		binder_dec_node_nilocked(ref->node, 1, 1);
1200 
1201 	hlist_del(&ref->node_entry);
1202 	delete_node = binder_dec_node_nilocked(ref->node, 0, 1);
1203 	binder_node_inner_unlock(ref->node);
1204 	/*
1205 	 * Clear ref->node unless we want the caller to free the node
1206 	 */
1207 	if (!delete_node) {
1208 		/*
1209 		 * The caller uses ref->node to determine
1210 		 * whether the node needs to be freed. Clear
1211 		 * it since the node is still alive.
1212 		 */
1213 		ref->node = NULL;
1214 	}
1215 
1216 	if (ref->death) {
1217 		binder_debug(BINDER_DEBUG_DEAD_BINDER,
1218 			     "%d delete ref %d desc %d has death notification\n",
1219 			      ref->proc->pid, ref->data.debug_id,
1220 			      ref->data.desc);
1221 		binder_dequeue_work(ref->proc, &ref->death->work);
1222 		binder_stats_deleted(BINDER_STAT_DEATH);
1223 	}
1224 
1225 	if (ref->freeze) {
1226 		binder_dequeue_work(ref->proc, &ref->freeze->work);
1227 		binder_stats_deleted(BINDER_STAT_FREEZE);
1228 	}
1229 
1230 	binder_stats_deleted(BINDER_STAT_REF);
1231 }
1232 
1233 /**
1234  * binder_inc_ref_olocked() - increment the ref for given handle
1235  * @ref:         ref to be incremented
1236  * @strong:      if true, strong increment, else weak
1237  * @target_list: list to queue node work on
1238  *
1239  * Increment the ref. @ref->proc->outer_lock must be held on entry
1240  *
1241  * Return: 0, if successful, else errno
1242  */
binder_inc_ref_olocked(struct binder_ref * ref,int strong,struct list_head * target_list)1243 static int binder_inc_ref_olocked(struct binder_ref *ref, int strong,
1244 				  struct list_head *target_list)
1245 {
1246 	int ret;
1247 
1248 	if (strong) {
1249 		if (ref->data.strong == 0) {
1250 			ret = binder_inc_node(ref->node, 1, 1, target_list);
1251 			if (ret)
1252 				return ret;
1253 		}
1254 		ref->data.strong++;
1255 	} else {
1256 		if (ref->data.weak == 0) {
1257 			ret = binder_inc_node(ref->node, 0, 1, target_list);
1258 			if (ret)
1259 				return ret;
1260 		}
1261 		ref->data.weak++;
1262 	}
1263 	return 0;
1264 }
1265 
1266 /**
1267  * binder_dec_ref_olocked() - dec the ref for given handle
1268  * @ref:	ref to be decremented
1269  * @strong:	if true, strong decrement, else weak
1270  *
1271  * Decrement the ref.
1272  *
1273  * Return: %true if ref is cleaned up and ready to be freed.
1274  */
binder_dec_ref_olocked(struct binder_ref * ref,int strong)1275 static bool binder_dec_ref_olocked(struct binder_ref *ref, int strong)
1276 {
1277 	if (strong) {
1278 		if (ref->data.strong == 0) {
1279 			binder_user_error("%d invalid dec strong, ref %d desc %d s %d w %d\n",
1280 					  ref->proc->pid, ref->data.debug_id,
1281 					  ref->data.desc, ref->data.strong,
1282 					  ref->data.weak);
1283 			return false;
1284 		}
1285 		ref->data.strong--;
1286 		if (ref->data.strong == 0)
1287 			binder_dec_node(ref->node, strong, 1);
1288 	} else {
1289 		if (ref->data.weak == 0) {
1290 			binder_user_error("%d invalid dec weak, ref %d desc %d s %d w %d\n",
1291 					  ref->proc->pid, ref->data.debug_id,
1292 					  ref->data.desc, ref->data.strong,
1293 					  ref->data.weak);
1294 			return false;
1295 		}
1296 		ref->data.weak--;
1297 	}
1298 	if (ref->data.strong == 0 && ref->data.weak == 0) {
1299 		binder_cleanup_ref_olocked(ref);
1300 		return true;
1301 	}
1302 	return false;
1303 }
1304 
1305 /**
1306  * binder_get_node_from_ref() - get the node from the given proc/desc
1307  * @proc:	proc containing the ref
1308  * @desc:	the handle associated with the ref
1309  * @need_strong_ref: if true, only return node if ref is strong
1310  * @rdata:	the id/refcount data for the ref
1311  *
1312  * Given a proc and ref handle, return the associated binder_node
1313  *
1314  * Return: a binder_node or NULL if not found or not strong when strong required
1315  */
binder_get_node_from_ref(struct binder_proc * proc,u32 desc,bool need_strong_ref,struct binder_ref_data * rdata)1316 static struct binder_node *binder_get_node_from_ref(
1317 		struct binder_proc *proc,
1318 		u32 desc, bool need_strong_ref,
1319 		struct binder_ref_data *rdata)
1320 {
1321 	struct binder_node *node;
1322 	struct binder_ref *ref;
1323 
1324 	binder_proc_lock(proc);
1325 	ref = binder_get_ref_olocked(proc, desc, need_strong_ref);
1326 	if (!ref)
1327 		goto err_no_ref;
1328 	node = ref->node;
1329 	/*
1330 	 * Take an implicit reference on the node to ensure
1331 	 * it stays alive until the call to binder_put_node()
1332 	 */
1333 	binder_inc_node_tmpref(node);
1334 	if (rdata)
1335 		*rdata = ref->data;
1336 	binder_proc_unlock(proc);
1337 
1338 	return node;
1339 
1340 err_no_ref:
1341 	binder_proc_unlock(proc);
1342 	return NULL;
1343 }
1344 
1345 /**
1346  * binder_free_ref() - free the binder_ref
1347  * @ref:	ref to free
1348  *
1349  * Free the binder_ref. Free the binder_node indicated by ref->node
1350  * (if non-NULL) and the binder_ref_death indicated by ref->death.
1351  */
binder_free_ref(struct binder_ref * ref)1352 static void binder_free_ref(struct binder_ref *ref)
1353 {
1354 	if (ref->node)
1355 		binder_free_node(ref->node);
1356 	kfree(ref->death);
1357 	kfree(ref->freeze);
1358 	kfree(ref);
1359 }
1360 
1361 /* shrink descriptor bitmap if needed */
try_shrink_dmap(struct binder_proc * proc)1362 static void try_shrink_dmap(struct binder_proc *proc)
1363 {
1364 	unsigned long *new;
1365 	int nbits;
1366 
1367 	binder_proc_lock(proc);
1368 	nbits = dbitmap_shrink_nbits(&proc->dmap);
1369 	binder_proc_unlock(proc);
1370 
1371 	if (!nbits)
1372 		return;
1373 
1374 	new = bitmap_zalloc(nbits, GFP_KERNEL);
1375 	binder_proc_lock(proc);
1376 	dbitmap_shrink(&proc->dmap, new, nbits);
1377 	binder_proc_unlock(proc);
1378 }
1379 
1380 /**
1381  * binder_update_ref_for_handle() - inc/dec the ref for given handle
1382  * @proc:	proc containing the ref
1383  * @desc:	the handle associated with the ref
1384  * @increment:	true=inc reference, false=dec reference
1385  * @strong:	true=strong reference, false=weak reference
1386  * @rdata:	the id/refcount data for the ref
1387  *
1388  * Given a proc and ref handle, increment or decrement the ref
1389  * according to "increment" arg.
1390  *
1391  * Return: 0 if successful, else errno
1392  */
binder_update_ref_for_handle(struct binder_proc * proc,uint32_t desc,bool increment,bool strong,struct binder_ref_data * rdata)1393 static int binder_update_ref_for_handle(struct binder_proc *proc,
1394 		uint32_t desc, bool increment, bool strong,
1395 		struct binder_ref_data *rdata)
1396 {
1397 	int ret = 0;
1398 	struct binder_ref *ref;
1399 	bool delete_ref = false;
1400 
1401 	binder_proc_lock(proc);
1402 	ref = binder_get_ref_olocked(proc, desc, strong);
1403 	if (!ref) {
1404 		ret = -EINVAL;
1405 		goto err_no_ref;
1406 	}
1407 	if (increment)
1408 		ret = binder_inc_ref_olocked(ref, strong, NULL);
1409 	else
1410 		delete_ref = binder_dec_ref_olocked(ref, strong);
1411 
1412 	if (rdata)
1413 		*rdata = ref->data;
1414 	binder_proc_unlock(proc);
1415 
1416 	if (delete_ref) {
1417 		binder_free_ref(ref);
1418 		try_shrink_dmap(proc);
1419 	}
1420 	return ret;
1421 
1422 err_no_ref:
1423 	binder_proc_unlock(proc);
1424 	return ret;
1425 }
1426 
1427 /**
1428  * binder_dec_ref_for_handle() - dec the ref for given handle
1429  * @proc:	proc containing the ref
1430  * @desc:	the handle associated with the ref
1431  * @strong:	true=strong reference, false=weak reference
1432  * @rdata:	the id/refcount data for the ref
1433  *
1434  * Just calls binder_update_ref_for_handle() to decrement the ref.
1435  *
1436  * Return: 0 if successful, else errno
1437  */
binder_dec_ref_for_handle(struct binder_proc * proc,uint32_t desc,bool strong,struct binder_ref_data * rdata)1438 static int binder_dec_ref_for_handle(struct binder_proc *proc,
1439 		uint32_t desc, bool strong, struct binder_ref_data *rdata)
1440 {
1441 	return binder_update_ref_for_handle(proc, desc, false, strong, rdata);
1442 }
1443 
1444 
1445 /**
1446  * binder_inc_ref_for_node() - increment the ref for given proc/node
1447  * @proc:	 proc containing the ref
1448  * @node:	 target node
1449  * @strong:	 true=strong reference, false=weak reference
1450  * @target_list: worklist to use if node is incremented
1451  * @rdata:	 the id/refcount data for the ref
1452  *
1453  * Given a proc and node, increment the ref. Create the ref if it
1454  * doesn't already exist
1455  *
1456  * Return: 0 if successful, else errno
1457  */
binder_inc_ref_for_node(struct binder_proc * proc,struct binder_node * node,bool strong,struct list_head * target_list,struct binder_ref_data * rdata)1458 static int binder_inc_ref_for_node(struct binder_proc *proc,
1459 			struct binder_node *node,
1460 			bool strong,
1461 			struct list_head *target_list,
1462 			struct binder_ref_data *rdata)
1463 {
1464 	struct binder_ref *ref;
1465 	struct binder_ref *new_ref = NULL;
1466 	int ret = 0;
1467 
1468 	binder_proc_lock(proc);
1469 	ref = binder_get_ref_for_node_olocked(proc, node, NULL);
1470 	if (!ref) {
1471 		binder_proc_unlock(proc);
1472 		new_ref = kzalloc(sizeof(*ref), GFP_KERNEL);
1473 		if (!new_ref)
1474 			return -ENOMEM;
1475 		binder_proc_lock(proc);
1476 		ref = binder_get_ref_for_node_olocked(proc, node, new_ref);
1477 	}
1478 	ret = binder_inc_ref_olocked(ref, strong, target_list);
1479 	*rdata = ref->data;
1480 	if (ret && ref == new_ref) {
1481 		/*
1482 		 * Cleanup the failed reference here as the target
1483 		 * could now be dead and have already released its
1484 		 * references by now. Calling on the new reference
1485 		 * with strong=0 and a tmp_refs will not decrement
1486 		 * the node. The new_ref gets kfree'd below.
1487 		 */
1488 		binder_cleanup_ref_olocked(new_ref);
1489 		ref = NULL;
1490 	}
1491 
1492 	binder_proc_unlock(proc);
1493 	if (new_ref && ref != new_ref)
1494 		/*
1495 		 * Another thread created the ref first so
1496 		 * free the one we allocated
1497 		 */
1498 		kfree(new_ref);
1499 	return ret;
1500 }
1501 
binder_pop_transaction_ilocked(struct binder_thread * target_thread,struct binder_transaction * t)1502 static void binder_pop_transaction_ilocked(struct binder_thread *target_thread,
1503 					   struct binder_transaction *t)
1504 {
1505 	BUG_ON(!target_thread);
1506 	assert_spin_locked(&target_thread->proc->inner_lock);
1507 	BUG_ON(target_thread->transaction_stack != t);
1508 	BUG_ON(target_thread->transaction_stack->from != target_thread);
1509 	target_thread->transaction_stack =
1510 		target_thread->transaction_stack->from_parent;
1511 	t->from = NULL;
1512 }
1513 
1514 /**
1515  * binder_thread_dec_tmpref() - decrement thread->tmp_ref
1516  * @thread:	thread to decrement
1517  *
1518  * A thread needs to be kept alive while being used to create or
1519  * handle a transaction. binder_get_txn_from() is used to safely
1520  * extract t->from from a binder_transaction and keep the thread
1521  * indicated by t->from from being freed. When done with that
1522  * binder_thread, this function is called to decrement the
1523  * tmp_ref and free if appropriate (thread has been released
1524  * and no transaction being processed by the driver)
1525  */
binder_thread_dec_tmpref(struct binder_thread * thread)1526 static void binder_thread_dec_tmpref(struct binder_thread *thread)
1527 {
1528 	/*
1529 	 * atomic is used to protect the counter value while
1530 	 * it cannot reach zero or thread->is_dead is false
1531 	 */
1532 	binder_inner_proc_lock(thread->proc);
1533 	atomic_dec(&thread->tmp_ref);
1534 	if (thread->is_dead && !atomic_read(&thread->tmp_ref)) {
1535 		binder_inner_proc_unlock(thread->proc);
1536 		binder_free_thread(thread);
1537 		return;
1538 	}
1539 	binder_inner_proc_unlock(thread->proc);
1540 }
1541 
1542 /**
1543  * binder_proc_dec_tmpref() - decrement proc->tmp_ref
1544  * @proc:	proc to decrement
1545  *
1546  * A binder_proc needs to be kept alive while being used to create or
1547  * handle a transaction. proc->tmp_ref is incremented when
1548  * creating a new transaction or the binder_proc is currently in-use
1549  * by threads that are being released. When done with the binder_proc,
1550  * this function is called to decrement the counter and free the
1551  * proc if appropriate (proc has been released, all threads have
1552  * been released and not currently in-use to process a transaction).
1553  */
binder_proc_dec_tmpref(struct binder_proc * proc)1554 static void binder_proc_dec_tmpref(struct binder_proc *proc)
1555 {
1556 	binder_inner_proc_lock(proc);
1557 	proc->tmp_ref--;
1558 	if (proc->is_dead && RB_EMPTY_ROOT(&proc->threads) &&
1559 			!proc->tmp_ref) {
1560 		binder_inner_proc_unlock(proc);
1561 		binder_free_proc(proc);
1562 		return;
1563 	}
1564 	binder_inner_proc_unlock(proc);
1565 }
1566 
1567 /**
1568  * binder_get_txn_from() - safely extract the "from" thread in transaction
1569  * @t:	binder transaction for t->from
1570  *
1571  * Atomically return the "from" thread and increment the tmp_ref
1572  * count for the thread to ensure it stays alive until
1573  * binder_thread_dec_tmpref() is called.
1574  *
1575  * Return: the value of t->from
1576  */
binder_get_txn_from(struct binder_transaction * t)1577 static struct binder_thread *binder_get_txn_from(
1578 		struct binder_transaction *t)
1579 {
1580 	struct binder_thread *from;
1581 
1582 	guard(spinlock)(&t->lock);
1583 	from = t->from;
1584 	if (from)
1585 		atomic_inc(&from->tmp_ref);
1586 	return from;
1587 }
1588 
1589 /**
1590  * binder_get_txn_from_and_acq_inner() - get t->from and acquire inner lock
1591  * @t:	binder transaction for t->from
1592  *
1593  * Same as binder_get_txn_from() except it also acquires the proc->inner_lock
1594  * to guarantee that the thread cannot be released while operating on it.
1595  * The caller must call binder_inner_proc_unlock() to release the inner lock
1596  * as well as call binder_dec_thread_txn() to release the reference.
1597  *
1598  * Return: the value of t->from
1599  */
binder_get_txn_from_and_acq_inner(struct binder_transaction * t)1600 static struct binder_thread *binder_get_txn_from_and_acq_inner(
1601 		struct binder_transaction *t)
1602 	__acquires(&t->from->proc->inner_lock)
1603 {
1604 	struct binder_thread *from;
1605 
1606 	from = binder_get_txn_from(t);
1607 	if (!from) {
1608 		__acquire(&from->proc->inner_lock);
1609 		return NULL;
1610 	}
1611 	binder_inner_proc_lock(from->proc);
1612 	if (t->from) {
1613 		BUG_ON(from != t->from);
1614 		return from;
1615 	}
1616 	binder_inner_proc_unlock(from->proc);
1617 	__acquire(&from->proc->inner_lock);
1618 	binder_thread_dec_tmpref(from);
1619 	return NULL;
1620 }
1621 
1622 /**
1623  * binder_free_txn_fixups() - free unprocessed fd fixups
1624  * @t:	binder transaction for t->from
1625  *
1626  * If the transaction is being torn down prior to being
1627  * processed by the target process, free all of the
1628  * fd fixups and fput the file structs. It is safe to
1629  * call this function after the fixups have been
1630  * processed -- in that case, the list will be empty.
1631  */
binder_free_txn_fixups(struct binder_transaction * t)1632 static void binder_free_txn_fixups(struct binder_transaction *t)
1633 {
1634 	struct binder_txn_fd_fixup *fixup, *tmp;
1635 
1636 	list_for_each_entry_safe(fixup, tmp, &t->fd_fixups, fixup_entry) {
1637 		fput(fixup->file);
1638 		if (fixup->target_fd >= 0)
1639 			put_unused_fd(fixup->target_fd);
1640 		list_del(&fixup->fixup_entry);
1641 		kfree(fixup);
1642 	}
1643 }
1644 
binder_txn_latency_free(struct binder_transaction * t)1645 static void binder_txn_latency_free(struct binder_transaction *t)
1646 {
1647 	int from_proc, from_thread, to_proc, to_thread;
1648 
1649 	spin_lock(&t->lock);
1650 	from_proc = t->from ? t->from->proc->pid : 0;
1651 	from_thread = t->from ? t->from->pid : 0;
1652 	to_proc = t->to_proc ? t->to_proc->pid : 0;
1653 	to_thread = t->to_thread ? t->to_thread->pid : 0;
1654 	spin_unlock(&t->lock);
1655 
1656 	trace_binder_txn_latency_free(t, from_proc, from_thread, to_proc, to_thread);
1657 }
1658 
binder_free_transaction(struct binder_transaction * t)1659 static void binder_free_transaction(struct binder_transaction *t)
1660 {
1661 	struct binder_proc *target_proc = t->to_proc;
1662 
1663 	if (target_proc) {
1664 		binder_inner_proc_lock(target_proc);
1665 		target_proc->outstanding_txns--;
1666 		if (target_proc->outstanding_txns < 0)
1667 			pr_warn("%s: Unexpected outstanding_txns %d\n",
1668 				__func__, target_proc->outstanding_txns);
1669 		if (!target_proc->outstanding_txns && target_proc->is_frozen)
1670 			wake_up_interruptible_all(&target_proc->freeze_wait);
1671 		if (t->buffer)
1672 			t->buffer->transaction = NULL;
1673 		binder_inner_proc_unlock(target_proc);
1674 	}
1675 	if (trace_binder_txn_latency_free_enabled())
1676 		binder_txn_latency_free(t);
1677 	/*
1678 	 * If the transaction has no target_proc, then
1679 	 * t->buffer->transaction has already been cleared.
1680 	 */
1681 	binder_free_txn_fixups(t);
1682 	kfree(t);
1683 	binder_stats_deleted(BINDER_STAT_TRANSACTION);
1684 }
1685 
binder_send_failed_reply(struct binder_transaction * t,uint32_t error_code)1686 static void binder_send_failed_reply(struct binder_transaction *t,
1687 				     uint32_t error_code)
1688 {
1689 	struct binder_thread *target_thread;
1690 	struct binder_transaction *next;
1691 
1692 	BUG_ON(t->flags & TF_ONE_WAY);
1693 	while (1) {
1694 		target_thread = binder_get_txn_from_and_acq_inner(t);
1695 		if (target_thread) {
1696 			binder_debug(BINDER_DEBUG_FAILED_TRANSACTION,
1697 				     "send failed reply for transaction %d to %d:%d\n",
1698 				      t->debug_id,
1699 				      target_thread->proc->pid,
1700 				      target_thread->pid);
1701 
1702 			binder_pop_transaction_ilocked(target_thread, t);
1703 			if (target_thread->reply_error.cmd == BR_OK) {
1704 				target_thread->reply_error.cmd = error_code;
1705 				binder_enqueue_thread_work_ilocked(
1706 					target_thread,
1707 					&target_thread->reply_error.work);
1708 				wake_up_interruptible(&target_thread->wait);
1709 			} else {
1710 				/*
1711 				 * Cannot get here for normal operation, but
1712 				 * we can if multiple synchronous transactions
1713 				 * are sent without blocking for responses.
1714 				 * Just ignore the 2nd error in this case.
1715 				 */
1716 				pr_warn("Unexpected reply error: %u\n",
1717 					target_thread->reply_error.cmd);
1718 			}
1719 			binder_inner_proc_unlock(target_thread->proc);
1720 			binder_thread_dec_tmpref(target_thread);
1721 			binder_free_transaction(t);
1722 			return;
1723 		}
1724 		__release(&target_thread->proc->inner_lock);
1725 		next = t->from_parent;
1726 
1727 		binder_debug(BINDER_DEBUG_FAILED_TRANSACTION,
1728 			     "send failed reply for transaction %d, target dead\n",
1729 			     t->debug_id);
1730 
1731 		binder_free_transaction(t);
1732 		if (next == NULL) {
1733 			binder_debug(BINDER_DEBUG_DEAD_BINDER,
1734 				     "reply failed, no target thread at root\n");
1735 			return;
1736 		}
1737 		t = next;
1738 		binder_debug(BINDER_DEBUG_DEAD_BINDER,
1739 			     "reply failed, no target thread -- retry %d\n",
1740 			      t->debug_id);
1741 	}
1742 }
1743 
1744 /**
1745  * binder_cleanup_transaction() - cleans up undelivered transaction
1746  * @t:		transaction that needs to be cleaned up
1747  * @reason:	reason the transaction wasn't delivered
1748  * @error_code:	error to return to caller (if synchronous call)
1749  */
binder_cleanup_transaction(struct binder_transaction * t,const char * reason,uint32_t error_code)1750 static void binder_cleanup_transaction(struct binder_transaction *t,
1751 				       const char *reason,
1752 				       uint32_t error_code)
1753 {
1754 	if (t->buffer->target_node && !(t->flags & TF_ONE_WAY)) {
1755 		binder_send_failed_reply(t, error_code);
1756 	} else {
1757 		binder_debug(BINDER_DEBUG_DEAD_TRANSACTION,
1758 			"undelivered transaction %d, %s\n",
1759 			t->debug_id, reason);
1760 		binder_free_transaction(t);
1761 	}
1762 }
1763 
1764 /**
1765  * binder_get_object() - gets object and checks for valid metadata
1766  * @proc:	binder_proc owning the buffer
1767  * @u:		sender's user pointer to base of buffer
1768  * @buffer:	binder_buffer that we're parsing.
1769  * @offset:	offset in the @buffer at which to validate an object.
1770  * @object:	struct binder_object to read into
1771  *
1772  * Copy the binder object at the given offset into @object. If @u is
1773  * provided then the copy is from the sender's buffer. If not, then
1774  * it is copied from the target's @buffer.
1775  *
1776  * Return:	If there's a valid metadata object at @offset, the
1777  *		size of that object. Otherwise, it returns zero. The object
1778  *		is read into the struct binder_object pointed to by @object.
1779  */
binder_get_object(struct binder_proc * proc,const void __user * u,struct binder_buffer * buffer,unsigned long offset,struct binder_object * object)1780 static size_t binder_get_object(struct binder_proc *proc,
1781 				const void __user *u,
1782 				struct binder_buffer *buffer,
1783 				unsigned long offset,
1784 				struct binder_object *object)
1785 {
1786 	size_t read_size;
1787 	struct binder_object_header *hdr;
1788 	size_t object_size = 0;
1789 
1790 	read_size = min_t(size_t, sizeof(*object), buffer->data_size - offset);
1791 	if (offset > buffer->data_size || read_size < sizeof(*hdr) ||
1792 	    !IS_ALIGNED(offset, sizeof(u32)))
1793 		return 0;
1794 
1795 	if (u) {
1796 		if (copy_from_user(object, u + offset, read_size))
1797 			return 0;
1798 	} else {
1799 		if (binder_alloc_copy_from_buffer(&proc->alloc, object, buffer,
1800 						  offset, read_size))
1801 			return 0;
1802 	}
1803 
1804 	/* Ok, now see if we read a complete object. */
1805 	hdr = &object->hdr;
1806 	switch (hdr->type) {
1807 	case BINDER_TYPE_BINDER:
1808 	case BINDER_TYPE_WEAK_BINDER:
1809 	case BINDER_TYPE_HANDLE:
1810 	case BINDER_TYPE_WEAK_HANDLE:
1811 		object_size = sizeof(struct flat_binder_object);
1812 		break;
1813 	case BINDER_TYPE_FD:
1814 		object_size = sizeof(struct binder_fd_object);
1815 		break;
1816 	case BINDER_TYPE_PTR:
1817 		object_size = sizeof(struct binder_buffer_object);
1818 		break;
1819 	case BINDER_TYPE_FDA:
1820 		object_size = sizeof(struct binder_fd_array_object);
1821 		break;
1822 	default:
1823 		return 0;
1824 	}
1825 	if (offset <= buffer->data_size - object_size &&
1826 	    buffer->data_size >= object_size)
1827 		return object_size;
1828 	else
1829 		return 0;
1830 }
1831 
1832 /**
1833  * binder_validate_ptr() - validates binder_buffer_object in a binder_buffer.
1834  * @proc:	binder_proc owning the buffer
1835  * @b:		binder_buffer containing the object
1836  * @object:	struct binder_object to read into
1837  * @index:	index in offset array at which the binder_buffer_object is
1838  *		located
1839  * @start_offset: points to the start of the offset array
1840  * @object_offsetp: offset of @object read from @b
1841  * @num_valid:	the number of valid offsets in the offset array
1842  *
1843  * Return:	If @index is within the valid range of the offset array
1844  *		described by @start and @num_valid, and if there's a valid
1845  *		binder_buffer_object at the offset found in index @index
1846  *		of the offset array, that object is returned. Otherwise,
1847  *		%NULL is returned.
1848  *		Note that the offset found in index @index itself is not
1849  *		verified; this function assumes that @num_valid elements
1850  *		from @start were previously verified to have valid offsets.
1851  *		If @object_offsetp is non-NULL, then the offset within
1852  *		@b is written to it.
1853  */
binder_validate_ptr(struct binder_proc * proc,struct binder_buffer * b,struct binder_object * object,binder_size_t index,binder_size_t start_offset,binder_size_t * object_offsetp,binder_size_t num_valid)1854 static struct binder_buffer_object *binder_validate_ptr(
1855 						struct binder_proc *proc,
1856 						struct binder_buffer *b,
1857 						struct binder_object *object,
1858 						binder_size_t index,
1859 						binder_size_t start_offset,
1860 						binder_size_t *object_offsetp,
1861 						binder_size_t num_valid)
1862 {
1863 	size_t object_size;
1864 	binder_size_t object_offset;
1865 	unsigned long buffer_offset;
1866 
1867 	if (index >= num_valid)
1868 		return NULL;
1869 
1870 	buffer_offset = start_offset + sizeof(binder_size_t) * index;
1871 	if (binder_alloc_copy_from_buffer(&proc->alloc, &object_offset,
1872 					  b, buffer_offset,
1873 					  sizeof(object_offset)))
1874 		return NULL;
1875 	object_size = binder_get_object(proc, NULL, b, object_offset, object);
1876 	if (!object_size || object->hdr.type != BINDER_TYPE_PTR)
1877 		return NULL;
1878 	if (object_offsetp)
1879 		*object_offsetp = object_offset;
1880 
1881 	return &object->bbo;
1882 }
1883 
1884 /**
1885  * binder_validate_fixup() - validates pointer/fd fixups happen in order.
1886  * @proc:		binder_proc owning the buffer
1887  * @b:			transaction buffer
1888  * @objects_start_offset: offset to start of objects buffer
1889  * @buffer_obj_offset:	offset to binder_buffer_object in which to fix up
1890  * @fixup_offset:	start offset in @buffer to fix up
1891  * @last_obj_offset:	offset to last binder_buffer_object that we fixed
1892  * @last_min_offset:	minimum fixup offset in object at @last_obj_offset
1893  *
1894  * Return:		%true if a fixup in buffer @buffer at offset @offset is
1895  *			allowed.
1896  *
1897  * For safety reasons, we only allow fixups inside a buffer to happen
1898  * at increasing offsets; additionally, we only allow fixup on the last
1899  * buffer object that was verified, or one of its parents.
1900  *
1901  * Example of what is allowed:
1902  *
1903  * A
1904  *   B (parent = A, offset = 0)
1905  *   C (parent = A, offset = 16)
1906  *     D (parent = C, offset = 0)
1907  *   E (parent = A, offset = 32) // min_offset is 16 (C.parent_offset)
1908  *
1909  * Examples of what is not allowed:
1910  *
1911  * Decreasing offsets within the same parent:
1912  * A
1913  *   C (parent = A, offset = 16)
1914  *   B (parent = A, offset = 0) // decreasing offset within A
1915  *
1916  * Referring to a parent that wasn't the last object or any of its parents:
1917  * A
1918  *   B (parent = A, offset = 0)
1919  *   C (parent = A, offset = 0)
1920  *   C (parent = A, offset = 16)
1921  *     D (parent = B, offset = 0) // B is not A or any of A's parents
1922  */
binder_validate_fixup(struct binder_proc * proc,struct binder_buffer * b,binder_size_t objects_start_offset,binder_size_t buffer_obj_offset,binder_size_t fixup_offset,binder_size_t last_obj_offset,binder_size_t last_min_offset)1923 static bool binder_validate_fixup(struct binder_proc *proc,
1924 				  struct binder_buffer *b,
1925 				  binder_size_t objects_start_offset,
1926 				  binder_size_t buffer_obj_offset,
1927 				  binder_size_t fixup_offset,
1928 				  binder_size_t last_obj_offset,
1929 				  binder_size_t last_min_offset)
1930 {
1931 	if (!last_obj_offset) {
1932 		/* Nothing to fix up in */
1933 		return false;
1934 	}
1935 
1936 	while (last_obj_offset != buffer_obj_offset) {
1937 		unsigned long buffer_offset;
1938 		struct binder_object last_object;
1939 		struct binder_buffer_object *last_bbo;
1940 		size_t object_size = binder_get_object(proc, NULL, b,
1941 						       last_obj_offset,
1942 						       &last_object);
1943 		if (object_size != sizeof(*last_bbo))
1944 			return false;
1945 
1946 		last_bbo = &last_object.bbo;
1947 		/*
1948 		 * Safe to retrieve the parent of last_obj, since it
1949 		 * was already previously verified by the driver.
1950 		 */
1951 		if ((last_bbo->flags & BINDER_BUFFER_FLAG_HAS_PARENT) == 0)
1952 			return false;
1953 		last_min_offset = last_bbo->parent_offset + sizeof(uintptr_t);
1954 		buffer_offset = objects_start_offset +
1955 			sizeof(binder_size_t) * last_bbo->parent;
1956 		if (binder_alloc_copy_from_buffer(&proc->alloc,
1957 						  &last_obj_offset,
1958 						  b, buffer_offset,
1959 						  sizeof(last_obj_offset)))
1960 			return false;
1961 	}
1962 	return (fixup_offset >= last_min_offset);
1963 }
1964 
1965 /**
1966  * struct binder_task_work_cb - for deferred close
1967  *
1968  * @twork:                callback_head for task work
1969  * @file:                 file to close
1970  *
1971  * Structure to pass task work to be handled after
1972  * returning from binder_ioctl() via task_work_add().
1973  */
1974 struct binder_task_work_cb {
1975 	struct callback_head twork;
1976 	struct file *file;
1977 };
1978 
1979 /**
1980  * binder_do_fd_close() - close list of file descriptors
1981  * @twork:	callback head for task work
1982  *
1983  * It is not safe to call ksys_close() during the binder_ioctl()
1984  * function if there is a chance that binder's own file descriptor
1985  * might be closed. This is to meet the requirements for using
1986  * fdget() (see comments for __fget_light()). Therefore use
1987  * task_work_add() to schedule the close operation once we have
1988  * returned from binder_ioctl(). This function is a callback
1989  * for that mechanism and does the actual ksys_close() on the
1990  * given file descriptor.
1991  */
binder_do_fd_close(struct callback_head * twork)1992 static void binder_do_fd_close(struct callback_head *twork)
1993 {
1994 	struct binder_task_work_cb *twcb = container_of(twork,
1995 			struct binder_task_work_cb, twork);
1996 
1997 	fput(twcb->file);
1998 	kfree(twcb);
1999 }
2000 
2001 /**
2002  * binder_deferred_fd_close() - schedule a close for the given file-descriptor
2003  * @fd:		file-descriptor to close
2004  *
2005  * See comments in binder_do_fd_close(). This function is used to schedule
2006  * a file-descriptor to be closed after returning from binder_ioctl().
2007  */
binder_deferred_fd_close(int fd)2008 static void binder_deferred_fd_close(int fd)
2009 {
2010 	struct binder_task_work_cb *twcb;
2011 
2012 	twcb = kzalloc(sizeof(*twcb), GFP_KERNEL);
2013 	if (!twcb)
2014 		return;
2015 	init_task_work(&twcb->twork, binder_do_fd_close);
2016 	twcb->file = file_close_fd(fd);
2017 	if (twcb->file) {
2018 		// pin it until binder_do_fd_close(); see comments there
2019 		get_file(twcb->file);
2020 		filp_close(twcb->file, current->files);
2021 		task_work_add(current, &twcb->twork, TWA_RESUME);
2022 	} else {
2023 		kfree(twcb);
2024 	}
2025 }
2026 
binder_transaction_buffer_release(struct binder_proc * proc,struct binder_thread * thread,struct binder_buffer * buffer,binder_size_t off_end_offset,bool is_failure)2027 static void binder_transaction_buffer_release(struct binder_proc *proc,
2028 					      struct binder_thread *thread,
2029 					      struct binder_buffer *buffer,
2030 					      binder_size_t off_end_offset,
2031 					      bool is_failure)
2032 {
2033 	int debug_id = buffer->debug_id;
2034 	binder_size_t off_start_offset, buffer_offset;
2035 
2036 	binder_debug(BINDER_DEBUG_TRANSACTION,
2037 		     "%d buffer release %d, size %zd-%zd, failed at %llx\n",
2038 		     proc->pid, buffer->debug_id,
2039 		     buffer->data_size, buffer->offsets_size,
2040 		     (unsigned long long)off_end_offset);
2041 
2042 	if (buffer->target_node)
2043 		binder_dec_node(buffer->target_node, 1, 0);
2044 
2045 	off_start_offset = ALIGN(buffer->data_size, sizeof(void *));
2046 
2047 	for (buffer_offset = off_start_offset; buffer_offset < off_end_offset;
2048 	     buffer_offset += sizeof(binder_size_t)) {
2049 		struct binder_object_header *hdr;
2050 		size_t object_size = 0;
2051 		struct binder_object object;
2052 		binder_size_t object_offset;
2053 
2054 		if (!binder_alloc_copy_from_buffer(&proc->alloc, &object_offset,
2055 						   buffer, buffer_offset,
2056 						   sizeof(object_offset)))
2057 			object_size = binder_get_object(proc, NULL, buffer,
2058 							object_offset, &object);
2059 		if (object_size == 0) {
2060 			pr_err("transaction release %d bad object at offset %lld, size %zd\n",
2061 			       debug_id, (u64)object_offset, buffer->data_size);
2062 			continue;
2063 		}
2064 		hdr = &object.hdr;
2065 		switch (hdr->type) {
2066 		case BINDER_TYPE_BINDER:
2067 		case BINDER_TYPE_WEAK_BINDER: {
2068 			struct flat_binder_object *fp;
2069 			struct binder_node *node;
2070 
2071 			fp = to_flat_binder_object(hdr);
2072 			node = binder_get_node(proc, fp->binder);
2073 			if (node == NULL) {
2074 				pr_err("transaction release %d bad node %016llx\n",
2075 				       debug_id, (u64)fp->binder);
2076 				break;
2077 			}
2078 			binder_debug(BINDER_DEBUG_TRANSACTION,
2079 				     "        node %d u%016llx\n",
2080 				     node->debug_id, (u64)node->ptr);
2081 			binder_dec_node(node, hdr->type == BINDER_TYPE_BINDER,
2082 					0);
2083 			binder_put_node(node);
2084 		} break;
2085 		case BINDER_TYPE_HANDLE:
2086 		case BINDER_TYPE_WEAK_HANDLE: {
2087 			struct flat_binder_object *fp;
2088 			struct binder_ref_data rdata;
2089 			int ret;
2090 
2091 			fp = to_flat_binder_object(hdr);
2092 			ret = binder_dec_ref_for_handle(proc, fp->handle,
2093 				hdr->type == BINDER_TYPE_HANDLE, &rdata);
2094 
2095 			if (ret) {
2096 				pr_err("transaction release %d bad handle %d, ret = %d\n",
2097 				 debug_id, fp->handle, ret);
2098 				break;
2099 			}
2100 			binder_debug(BINDER_DEBUG_TRANSACTION,
2101 				     "        ref %d desc %d\n",
2102 				     rdata.debug_id, rdata.desc);
2103 		} break;
2104 
2105 		case BINDER_TYPE_FD: {
2106 			/*
2107 			 * No need to close the file here since user-space
2108 			 * closes it for successfully delivered
2109 			 * transactions. For transactions that weren't
2110 			 * delivered, the new fd was never allocated so
2111 			 * there is no need to close and the fput on the
2112 			 * file is done when the transaction is torn
2113 			 * down.
2114 			 */
2115 		} break;
2116 		case BINDER_TYPE_PTR:
2117 			/*
2118 			 * Nothing to do here, this will get cleaned up when the
2119 			 * transaction buffer gets freed
2120 			 */
2121 			break;
2122 		case BINDER_TYPE_FDA: {
2123 			struct binder_fd_array_object *fda;
2124 			struct binder_buffer_object *parent;
2125 			struct binder_object ptr_object;
2126 			binder_size_t fda_offset;
2127 			size_t fd_index;
2128 			binder_size_t fd_buf_size;
2129 			binder_size_t num_valid;
2130 
2131 			if (is_failure) {
2132 				/*
2133 				 * The fd fixups have not been applied so no
2134 				 * fds need to be closed.
2135 				 */
2136 				continue;
2137 			}
2138 
2139 			num_valid = (buffer_offset - off_start_offset) /
2140 						sizeof(binder_size_t);
2141 			fda = to_binder_fd_array_object(hdr);
2142 			parent = binder_validate_ptr(proc, buffer, &ptr_object,
2143 						     fda->parent,
2144 						     off_start_offset,
2145 						     NULL,
2146 						     num_valid);
2147 			if (!parent) {
2148 				pr_err("transaction release %d bad parent offset\n",
2149 				       debug_id);
2150 				continue;
2151 			}
2152 			fd_buf_size = sizeof(u32) * fda->num_fds;
2153 			if (fda->num_fds >= SIZE_MAX / sizeof(u32)) {
2154 				pr_err("transaction release %d invalid number of fds (%lld)\n",
2155 				       debug_id, (u64)fda->num_fds);
2156 				continue;
2157 			}
2158 			if (fd_buf_size > parent->length ||
2159 			    fda->parent_offset > parent->length - fd_buf_size) {
2160 				/* No space for all file descriptors here. */
2161 				pr_err("transaction release %d not enough space for %lld fds in buffer\n",
2162 				       debug_id, (u64)fda->num_fds);
2163 				continue;
2164 			}
2165 			/*
2166 			 * the source data for binder_buffer_object is visible
2167 			 * to user-space and the @buffer element is the user
2168 			 * pointer to the buffer_object containing the fd_array.
2169 			 * Convert the address to an offset relative to
2170 			 * the base of the transaction buffer.
2171 			 */
2172 			fda_offset = parent->buffer - buffer->user_data +
2173 				fda->parent_offset;
2174 			for (fd_index = 0; fd_index < fda->num_fds;
2175 			     fd_index++) {
2176 				u32 fd;
2177 				int err;
2178 				binder_size_t offset = fda_offset +
2179 					fd_index * sizeof(fd);
2180 
2181 				err = binder_alloc_copy_from_buffer(
2182 						&proc->alloc, &fd, buffer,
2183 						offset, sizeof(fd));
2184 				WARN_ON(err);
2185 				if (!err) {
2186 					binder_deferred_fd_close(fd);
2187 					/*
2188 					 * Need to make sure the thread goes
2189 					 * back to userspace to complete the
2190 					 * deferred close
2191 					 */
2192 					if (thread)
2193 						thread->looper_need_return = true;
2194 				}
2195 			}
2196 		} break;
2197 		default:
2198 			pr_err("transaction release %d bad object type %x\n",
2199 				debug_id, hdr->type);
2200 			break;
2201 		}
2202 	}
2203 }
2204 
2205 /* Clean up all the objects in the buffer */
binder_release_entire_buffer(struct binder_proc * proc,struct binder_thread * thread,struct binder_buffer * buffer,bool is_failure)2206 static inline void binder_release_entire_buffer(struct binder_proc *proc,
2207 						struct binder_thread *thread,
2208 						struct binder_buffer *buffer,
2209 						bool is_failure)
2210 {
2211 	binder_size_t off_end_offset;
2212 
2213 	off_end_offset = ALIGN(buffer->data_size, sizeof(void *));
2214 	off_end_offset += buffer->offsets_size;
2215 
2216 	binder_transaction_buffer_release(proc, thread, buffer,
2217 					  off_end_offset, is_failure);
2218 }
2219 
binder_translate_binder(struct flat_binder_object * fp,struct binder_transaction * t,struct binder_thread * thread)2220 static int binder_translate_binder(struct flat_binder_object *fp,
2221 				   struct binder_transaction *t,
2222 				   struct binder_thread *thread)
2223 {
2224 	struct binder_node *node;
2225 	struct binder_proc *proc = thread->proc;
2226 	struct binder_proc *target_proc = t->to_proc;
2227 	struct binder_ref_data rdata;
2228 	int ret = 0;
2229 
2230 	node = binder_get_node(proc, fp->binder);
2231 	if (!node) {
2232 		node = binder_new_node(proc, fp);
2233 		if (!node)
2234 			return -ENOMEM;
2235 	}
2236 	if (fp->cookie != node->cookie) {
2237 		binder_user_error("%d:%d sending u%016llx node %d, cookie mismatch %016llx != %016llx\n",
2238 				  proc->pid, thread->pid, (u64)fp->binder,
2239 				  node->debug_id, (u64)fp->cookie,
2240 				  (u64)node->cookie);
2241 		ret = -EINVAL;
2242 		goto done;
2243 	}
2244 	if (security_binder_transfer_binder(proc->cred, target_proc->cred)) {
2245 		ret = -EPERM;
2246 		goto done;
2247 	}
2248 
2249 	ret = binder_inc_ref_for_node(target_proc, node,
2250 			fp->hdr.type == BINDER_TYPE_BINDER,
2251 			&thread->todo, &rdata);
2252 	if (ret)
2253 		goto done;
2254 
2255 	if (fp->hdr.type == BINDER_TYPE_BINDER)
2256 		fp->hdr.type = BINDER_TYPE_HANDLE;
2257 	else
2258 		fp->hdr.type = BINDER_TYPE_WEAK_HANDLE;
2259 	fp->binder = 0;
2260 	fp->handle = rdata.desc;
2261 	fp->cookie = 0;
2262 
2263 	trace_binder_transaction_node_to_ref(t, node, &rdata);
2264 	binder_debug(BINDER_DEBUG_TRANSACTION,
2265 		     "        node %d u%016llx -> ref %d desc %d\n",
2266 		     node->debug_id, (u64)node->ptr,
2267 		     rdata.debug_id, rdata.desc);
2268 done:
2269 	binder_put_node(node);
2270 	return ret;
2271 }
2272 
binder_translate_handle(struct flat_binder_object * fp,struct binder_transaction * t,struct binder_thread * thread)2273 static int binder_translate_handle(struct flat_binder_object *fp,
2274 				   struct binder_transaction *t,
2275 				   struct binder_thread *thread)
2276 {
2277 	struct binder_proc *proc = thread->proc;
2278 	struct binder_proc *target_proc = t->to_proc;
2279 	struct binder_node *node;
2280 	struct binder_ref_data src_rdata;
2281 	int ret = 0;
2282 
2283 	node = binder_get_node_from_ref(proc, fp->handle,
2284 			fp->hdr.type == BINDER_TYPE_HANDLE, &src_rdata);
2285 	if (!node) {
2286 		binder_user_error("%d:%d got transaction with invalid handle, %d\n",
2287 				  proc->pid, thread->pid, fp->handle);
2288 		return -EINVAL;
2289 	}
2290 	if (security_binder_transfer_binder(proc->cred, target_proc->cred)) {
2291 		ret = -EPERM;
2292 		goto done;
2293 	}
2294 
2295 	binder_node_lock(node);
2296 	if (node->proc == target_proc) {
2297 		if (fp->hdr.type == BINDER_TYPE_HANDLE)
2298 			fp->hdr.type = BINDER_TYPE_BINDER;
2299 		else
2300 			fp->hdr.type = BINDER_TYPE_WEAK_BINDER;
2301 		fp->binder = node->ptr;
2302 		fp->cookie = node->cookie;
2303 		if (node->proc)
2304 			binder_inner_proc_lock(node->proc);
2305 		else
2306 			__acquire(&node->proc->inner_lock);
2307 		binder_inc_node_nilocked(node,
2308 					 fp->hdr.type == BINDER_TYPE_BINDER,
2309 					 0, NULL);
2310 		if (node->proc)
2311 			binder_inner_proc_unlock(node->proc);
2312 		else
2313 			__release(&node->proc->inner_lock);
2314 		trace_binder_transaction_ref_to_node(t, node, &src_rdata);
2315 		binder_debug(BINDER_DEBUG_TRANSACTION,
2316 			     "        ref %d desc %d -> node %d u%016llx\n",
2317 			     src_rdata.debug_id, src_rdata.desc, node->debug_id,
2318 			     (u64)node->ptr);
2319 		binder_node_unlock(node);
2320 	} else {
2321 		struct binder_ref_data dest_rdata;
2322 
2323 		binder_node_unlock(node);
2324 		ret = binder_inc_ref_for_node(target_proc, node,
2325 				fp->hdr.type == BINDER_TYPE_HANDLE,
2326 				NULL, &dest_rdata);
2327 		if (ret)
2328 			goto done;
2329 
2330 		fp->binder = 0;
2331 		fp->handle = dest_rdata.desc;
2332 		fp->cookie = 0;
2333 		trace_binder_transaction_ref_to_ref(t, node, &src_rdata,
2334 						    &dest_rdata);
2335 		binder_debug(BINDER_DEBUG_TRANSACTION,
2336 			     "        ref %d desc %d -> ref %d desc %d (node %d)\n",
2337 			     src_rdata.debug_id, src_rdata.desc,
2338 			     dest_rdata.debug_id, dest_rdata.desc,
2339 			     node->debug_id);
2340 	}
2341 done:
2342 	binder_put_node(node);
2343 	return ret;
2344 }
2345 
binder_translate_fd(u32 fd,binder_size_t fd_offset,struct binder_transaction * t,struct binder_thread * thread,struct binder_transaction * in_reply_to)2346 static int binder_translate_fd(u32 fd, binder_size_t fd_offset,
2347 			       struct binder_transaction *t,
2348 			       struct binder_thread *thread,
2349 			       struct binder_transaction *in_reply_to)
2350 {
2351 	struct binder_proc *proc = thread->proc;
2352 	struct binder_proc *target_proc = t->to_proc;
2353 	struct binder_txn_fd_fixup *fixup;
2354 	struct file *file;
2355 	int ret = 0;
2356 	bool target_allows_fd;
2357 
2358 	if (in_reply_to)
2359 		target_allows_fd = !!(in_reply_to->flags & TF_ACCEPT_FDS);
2360 	else
2361 		target_allows_fd = t->buffer->target_node->accept_fds;
2362 	if (!target_allows_fd) {
2363 		binder_user_error("%d:%d got %s with fd, %d, but target does not allow fds\n",
2364 				  proc->pid, thread->pid,
2365 				  in_reply_to ? "reply" : "transaction",
2366 				  fd);
2367 		ret = -EPERM;
2368 		goto err_fd_not_accepted;
2369 	}
2370 
2371 	file = fget(fd);
2372 	if (!file) {
2373 		binder_user_error("%d:%d got transaction with invalid fd, %d\n",
2374 				  proc->pid, thread->pid, fd);
2375 		ret = -EBADF;
2376 		goto err_fget;
2377 	}
2378 	ret = security_binder_transfer_file(proc->cred, target_proc->cred, file);
2379 	if (ret < 0) {
2380 		ret = -EPERM;
2381 		goto err_security;
2382 	}
2383 
2384 	/*
2385 	 * Add fixup record for this transaction. The allocation
2386 	 * of the fd in the target needs to be done from a
2387 	 * target thread.
2388 	 */
2389 	fixup = kzalloc(sizeof(*fixup), GFP_KERNEL);
2390 	if (!fixup) {
2391 		ret = -ENOMEM;
2392 		goto err_alloc;
2393 	}
2394 	fixup->file = file;
2395 	fixup->offset = fd_offset;
2396 	fixup->target_fd = -1;
2397 	trace_binder_transaction_fd_send(t, fd, fixup->offset);
2398 	list_add_tail(&fixup->fixup_entry, &t->fd_fixups);
2399 
2400 	return ret;
2401 
2402 err_alloc:
2403 err_security:
2404 	fput(file);
2405 err_fget:
2406 err_fd_not_accepted:
2407 	return ret;
2408 }
2409 
2410 /**
2411  * struct binder_ptr_fixup - data to be fixed-up in target buffer
2412  * @offset:      offset in target buffer to fixup
2413  * @skip_size:   bytes to skip in copy (fixup will be written later)
2414  * @fixup_data:  data to write at fixup offset
2415  * @node:        list node
2416  *
2417  * This is used for the pointer fixup list (pf) which is created and consumed
2418  * during binder_transaction() and is only accessed locally. No
2419  * locking is necessary.
2420  *
2421  * The list is ordered by @offset.
2422  */
2423 struct binder_ptr_fixup {
2424 	binder_size_t offset;
2425 	size_t skip_size;
2426 	binder_uintptr_t fixup_data;
2427 	struct list_head node;
2428 };
2429 
2430 /**
2431  * struct binder_sg_copy - scatter-gather data to be copied
2432  * @offset:        offset in target buffer
2433  * @sender_uaddr:  user address in source buffer
2434  * @length:        bytes to copy
2435  * @node:          list node
2436  *
2437  * This is used for the sg copy list (sgc) which is created and consumed
2438  * during binder_transaction() and is only accessed locally. No
2439  * locking is necessary.
2440  *
2441  * The list is ordered by @offset.
2442  */
2443 struct binder_sg_copy {
2444 	binder_size_t offset;
2445 	const void __user *sender_uaddr;
2446 	size_t length;
2447 	struct list_head node;
2448 };
2449 
2450 /**
2451  * binder_do_deferred_txn_copies() - copy and fixup scatter-gather data
2452  * @alloc:	binder_alloc associated with @buffer
2453  * @buffer:	binder buffer in target process
2454  * @sgc_head:	list_head of scatter-gather copy list
2455  * @pf_head:	list_head of pointer fixup list
2456  *
2457  * Processes all elements of @sgc_head, applying fixups from @pf_head
2458  * and copying the scatter-gather data from the source process' user
2459  * buffer to the target's buffer. It is expected that the list creation
2460  * and processing all occurs during binder_transaction() so these lists
2461  * are only accessed in local context.
2462  *
2463  * Return: 0=success, else -errno
2464  */
binder_do_deferred_txn_copies(struct binder_alloc * alloc,struct binder_buffer * buffer,struct list_head * sgc_head,struct list_head * pf_head)2465 static int binder_do_deferred_txn_copies(struct binder_alloc *alloc,
2466 					 struct binder_buffer *buffer,
2467 					 struct list_head *sgc_head,
2468 					 struct list_head *pf_head)
2469 {
2470 	int ret = 0;
2471 	struct binder_sg_copy *sgc, *tmpsgc;
2472 	struct binder_ptr_fixup *tmppf;
2473 	struct binder_ptr_fixup *pf =
2474 		list_first_entry_or_null(pf_head, struct binder_ptr_fixup,
2475 					 node);
2476 
2477 	list_for_each_entry_safe(sgc, tmpsgc, sgc_head, node) {
2478 		size_t bytes_copied = 0;
2479 
2480 		while (bytes_copied < sgc->length) {
2481 			size_t copy_size;
2482 			size_t bytes_left = sgc->length - bytes_copied;
2483 			size_t offset = sgc->offset + bytes_copied;
2484 
2485 			/*
2486 			 * We copy up to the fixup (pointed to by pf)
2487 			 */
2488 			copy_size = pf ? min(bytes_left, (size_t)pf->offset - offset)
2489 				       : bytes_left;
2490 			if (!ret && copy_size)
2491 				ret = binder_alloc_copy_user_to_buffer(
2492 						alloc, buffer,
2493 						offset,
2494 						sgc->sender_uaddr + bytes_copied,
2495 						copy_size);
2496 			bytes_copied += copy_size;
2497 			if (copy_size != bytes_left) {
2498 				BUG_ON(!pf);
2499 				/* we stopped at a fixup offset */
2500 				if (pf->skip_size) {
2501 					/*
2502 					 * we are just skipping. This is for
2503 					 * BINDER_TYPE_FDA where the translated
2504 					 * fds will be fixed up when we get
2505 					 * to target context.
2506 					 */
2507 					bytes_copied += pf->skip_size;
2508 				} else {
2509 					/* apply the fixup indicated by pf */
2510 					if (!ret)
2511 						ret = binder_alloc_copy_to_buffer(
2512 							alloc, buffer,
2513 							pf->offset,
2514 							&pf->fixup_data,
2515 							sizeof(pf->fixup_data));
2516 					bytes_copied += sizeof(pf->fixup_data);
2517 				}
2518 				list_del(&pf->node);
2519 				kfree(pf);
2520 				pf = list_first_entry_or_null(pf_head,
2521 						struct binder_ptr_fixup, node);
2522 			}
2523 		}
2524 		list_del(&sgc->node);
2525 		kfree(sgc);
2526 	}
2527 	list_for_each_entry_safe(pf, tmppf, pf_head, node) {
2528 		BUG_ON(pf->skip_size == 0);
2529 		list_del(&pf->node);
2530 		kfree(pf);
2531 	}
2532 	BUG_ON(!list_empty(sgc_head));
2533 
2534 	return ret > 0 ? -EINVAL : ret;
2535 }
2536 
2537 /**
2538  * binder_cleanup_deferred_txn_lists() - free specified lists
2539  * @sgc_head:	list_head of scatter-gather copy list
2540  * @pf_head:	list_head of pointer fixup list
2541  *
2542  * Called to clean up @sgc_head and @pf_head if there is an
2543  * error.
2544  */
binder_cleanup_deferred_txn_lists(struct list_head * sgc_head,struct list_head * pf_head)2545 static void binder_cleanup_deferred_txn_lists(struct list_head *sgc_head,
2546 					      struct list_head *pf_head)
2547 {
2548 	struct binder_sg_copy *sgc, *tmpsgc;
2549 	struct binder_ptr_fixup *pf, *tmppf;
2550 
2551 	list_for_each_entry_safe(sgc, tmpsgc, sgc_head, node) {
2552 		list_del(&sgc->node);
2553 		kfree(sgc);
2554 	}
2555 	list_for_each_entry_safe(pf, tmppf, pf_head, node) {
2556 		list_del(&pf->node);
2557 		kfree(pf);
2558 	}
2559 }
2560 
2561 /**
2562  * binder_defer_copy() - queue a scatter-gather buffer for copy
2563  * @sgc_head:		list_head of scatter-gather copy list
2564  * @offset:		binder buffer offset in target process
2565  * @sender_uaddr:	user address in source process
2566  * @length:		bytes to copy
2567  *
2568  * Specify a scatter-gather block to be copied. The actual copy must
2569  * be deferred until all the needed fixups are identified and queued.
2570  * Then the copy and fixups are done together so un-translated values
2571  * from the source are never visible in the target buffer.
2572  *
2573  * We are guaranteed that repeated calls to this function will have
2574  * monotonically increasing @offset values so the list will naturally
2575  * be ordered.
2576  *
2577  * Return: 0=success, else -errno
2578  */
binder_defer_copy(struct list_head * sgc_head,binder_size_t offset,const void __user * sender_uaddr,size_t length)2579 static int binder_defer_copy(struct list_head *sgc_head, binder_size_t offset,
2580 			     const void __user *sender_uaddr, size_t length)
2581 {
2582 	struct binder_sg_copy *bc = kzalloc(sizeof(*bc), GFP_KERNEL);
2583 
2584 	if (!bc)
2585 		return -ENOMEM;
2586 
2587 	bc->offset = offset;
2588 	bc->sender_uaddr = sender_uaddr;
2589 	bc->length = length;
2590 	INIT_LIST_HEAD(&bc->node);
2591 
2592 	/*
2593 	 * We are guaranteed that the deferred copies are in-order
2594 	 * so just add to the tail.
2595 	 */
2596 	list_add_tail(&bc->node, sgc_head);
2597 
2598 	return 0;
2599 }
2600 
2601 /**
2602  * binder_add_fixup() - queue a fixup to be applied to sg copy
2603  * @pf_head:	list_head of binder ptr fixup list
2604  * @offset:	binder buffer offset in target process
2605  * @fixup:	bytes to be copied for fixup
2606  * @skip_size:	bytes to skip when copying (fixup will be applied later)
2607  *
2608  * Add the specified fixup to a list ordered by @offset. When copying
2609  * the scatter-gather buffers, the fixup will be copied instead of
2610  * data from the source buffer. For BINDER_TYPE_FDA fixups, the fixup
2611  * will be applied later (in target process context), so we just skip
2612  * the bytes specified by @skip_size. If @skip_size is 0, we copy the
2613  * value in @fixup.
2614  *
2615  * This function is called *mostly* in @offset order, but there are
2616  * exceptions. Since out-of-order inserts are relatively uncommon,
2617  * we insert the new element by searching backward from the tail of
2618  * the list.
2619  *
2620  * Return: 0=success, else -errno
2621  */
binder_add_fixup(struct list_head * pf_head,binder_size_t offset,binder_uintptr_t fixup,size_t skip_size)2622 static int binder_add_fixup(struct list_head *pf_head, binder_size_t offset,
2623 			    binder_uintptr_t fixup, size_t skip_size)
2624 {
2625 	struct binder_ptr_fixup *pf = kzalloc(sizeof(*pf), GFP_KERNEL);
2626 	struct binder_ptr_fixup *tmppf;
2627 
2628 	if (!pf)
2629 		return -ENOMEM;
2630 
2631 	pf->offset = offset;
2632 	pf->fixup_data = fixup;
2633 	pf->skip_size = skip_size;
2634 	INIT_LIST_HEAD(&pf->node);
2635 
2636 	/* Fixups are *mostly* added in-order, but there are some
2637 	 * exceptions. Look backwards through list for insertion point.
2638 	 */
2639 	list_for_each_entry_reverse(tmppf, pf_head, node) {
2640 		if (tmppf->offset < pf->offset) {
2641 			list_add(&pf->node, &tmppf->node);
2642 			return 0;
2643 		}
2644 	}
2645 	/*
2646 	 * if we get here, then the new offset is the lowest so
2647 	 * insert at the head
2648 	 */
2649 	list_add(&pf->node, pf_head);
2650 	return 0;
2651 }
2652 
binder_translate_fd_array(struct list_head * pf_head,struct binder_fd_array_object * fda,const void __user * sender_ubuffer,struct binder_buffer_object * parent,struct binder_buffer_object * sender_uparent,struct binder_transaction * t,struct binder_thread * thread,struct binder_transaction * in_reply_to)2653 static int binder_translate_fd_array(struct list_head *pf_head,
2654 				     struct binder_fd_array_object *fda,
2655 				     const void __user *sender_ubuffer,
2656 				     struct binder_buffer_object *parent,
2657 				     struct binder_buffer_object *sender_uparent,
2658 				     struct binder_transaction *t,
2659 				     struct binder_thread *thread,
2660 				     struct binder_transaction *in_reply_to)
2661 {
2662 	binder_size_t fdi, fd_buf_size;
2663 	binder_size_t fda_offset;
2664 	const void __user *sender_ufda_base;
2665 	struct binder_proc *proc = thread->proc;
2666 	int ret;
2667 
2668 	if (fda->num_fds == 0)
2669 		return 0;
2670 
2671 	fd_buf_size = sizeof(u32) * fda->num_fds;
2672 	if (fda->num_fds >= SIZE_MAX / sizeof(u32)) {
2673 		binder_user_error("%d:%d got transaction with invalid number of fds (%lld)\n",
2674 				  proc->pid, thread->pid, (u64)fda->num_fds);
2675 		return -EINVAL;
2676 	}
2677 	if (fd_buf_size > parent->length ||
2678 	    fda->parent_offset > parent->length - fd_buf_size) {
2679 		/* No space for all file descriptors here. */
2680 		binder_user_error("%d:%d not enough space to store %lld fds in buffer\n",
2681 				  proc->pid, thread->pid, (u64)fda->num_fds);
2682 		return -EINVAL;
2683 	}
2684 	/*
2685 	 * the source data for binder_buffer_object is visible
2686 	 * to user-space and the @buffer element is the user
2687 	 * pointer to the buffer_object containing the fd_array.
2688 	 * Convert the address to an offset relative to
2689 	 * the base of the transaction buffer.
2690 	 */
2691 	fda_offset = parent->buffer - t->buffer->user_data +
2692 		fda->parent_offset;
2693 	sender_ufda_base = (void __user *)(uintptr_t)sender_uparent->buffer +
2694 				fda->parent_offset;
2695 
2696 	if (!IS_ALIGNED((unsigned long)fda_offset, sizeof(u32)) ||
2697 	    !IS_ALIGNED((unsigned long)sender_ufda_base, sizeof(u32))) {
2698 		binder_user_error("%d:%d parent offset not aligned correctly.\n",
2699 				  proc->pid, thread->pid);
2700 		return -EINVAL;
2701 	}
2702 	ret = binder_add_fixup(pf_head, fda_offset, 0, fda->num_fds * sizeof(u32));
2703 	if (ret)
2704 		return ret;
2705 
2706 	for (fdi = 0; fdi < fda->num_fds; fdi++) {
2707 		u32 fd;
2708 		binder_size_t offset = fda_offset + fdi * sizeof(fd);
2709 		binder_size_t sender_uoffset = fdi * sizeof(fd);
2710 
2711 		ret = copy_from_user(&fd, sender_ufda_base + sender_uoffset, sizeof(fd));
2712 		if (!ret)
2713 			ret = binder_translate_fd(fd, offset, t, thread,
2714 						  in_reply_to);
2715 		if (ret)
2716 			return ret > 0 ? -EINVAL : ret;
2717 	}
2718 	return 0;
2719 }
2720 
binder_fixup_parent(struct list_head * pf_head,struct binder_transaction * t,struct binder_thread * thread,struct binder_buffer_object * bp,binder_size_t off_start_offset,binder_size_t num_valid,binder_size_t last_fixup_obj_off,binder_size_t last_fixup_min_off)2721 static int binder_fixup_parent(struct list_head *pf_head,
2722 			       struct binder_transaction *t,
2723 			       struct binder_thread *thread,
2724 			       struct binder_buffer_object *bp,
2725 			       binder_size_t off_start_offset,
2726 			       binder_size_t num_valid,
2727 			       binder_size_t last_fixup_obj_off,
2728 			       binder_size_t last_fixup_min_off)
2729 {
2730 	struct binder_buffer_object *parent;
2731 	struct binder_buffer *b = t->buffer;
2732 	struct binder_proc *proc = thread->proc;
2733 	struct binder_proc *target_proc = t->to_proc;
2734 	struct binder_object object;
2735 	binder_size_t buffer_offset;
2736 	binder_size_t parent_offset;
2737 
2738 	if (!(bp->flags & BINDER_BUFFER_FLAG_HAS_PARENT))
2739 		return 0;
2740 
2741 	parent = binder_validate_ptr(target_proc, b, &object, bp->parent,
2742 				     off_start_offset, &parent_offset,
2743 				     num_valid);
2744 	if (!parent) {
2745 		binder_user_error("%d:%d got transaction with invalid parent offset or type\n",
2746 				  proc->pid, thread->pid);
2747 		return -EINVAL;
2748 	}
2749 
2750 	if (!binder_validate_fixup(target_proc, b, off_start_offset,
2751 				   parent_offset, bp->parent_offset,
2752 				   last_fixup_obj_off,
2753 				   last_fixup_min_off)) {
2754 		binder_user_error("%d:%d got transaction with out-of-order buffer fixup\n",
2755 				  proc->pid, thread->pid);
2756 		return -EINVAL;
2757 	}
2758 
2759 	if (parent->length < sizeof(binder_uintptr_t) ||
2760 	    bp->parent_offset > parent->length - sizeof(binder_uintptr_t)) {
2761 		/* No space for a pointer here! */
2762 		binder_user_error("%d:%d got transaction with invalid parent offset\n",
2763 				  proc->pid, thread->pid);
2764 		return -EINVAL;
2765 	}
2766 
2767 	buffer_offset = bp->parent_offset + parent->buffer - b->user_data;
2768 
2769 	return binder_add_fixup(pf_head, buffer_offset, bp->buffer, 0);
2770 }
2771 
2772 /**
2773  * binder_can_update_transaction() - Can a txn be superseded by an updated one?
2774  * @t1: the pending async txn in the frozen process
2775  * @t2: the new async txn to supersede the outdated pending one
2776  *
2777  * Return:  true if t2 can supersede t1
2778  *          false if t2 can not supersede t1
2779  */
binder_can_update_transaction(struct binder_transaction * t1,struct binder_transaction * t2)2780 static bool binder_can_update_transaction(struct binder_transaction *t1,
2781 					  struct binder_transaction *t2)
2782 {
2783 	if ((t1->flags & t2->flags & (TF_ONE_WAY | TF_UPDATE_TXN)) !=
2784 	    (TF_ONE_WAY | TF_UPDATE_TXN) || !t1->to_proc || !t2->to_proc)
2785 		return false;
2786 	if (t1->to_proc->tsk == t2->to_proc->tsk && t1->code == t2->code &&
2787 	    t1->flags == t2->flags && t1->buffer->pid == t2->buffer->pid &&
2788 	    t1->buffer->target_node->ptr == t2->buffer->target_node->ptr &&
2789 	    t1->buffer->target_node->cookie == t2->buffer->target_node->cookie)
2790 		return true;
2791 	return false;
2792 }
2793 
2794 /**
2795  * binder_find_outdated_transaction_ilocked() - Find the outdated transaction
2796  * @t:		 new async transaction
2797  * @target_list: list to find outdated transaction
2798  *
2799  * Return: the outdated transaction if found
2800  *         NULL if no outdated transacton can be found
2801  *
2802  * Requires the proc->inner_lock to be held.
2803  */
2804 static struct binder_transaction *
binder_find_outdated_transaction_ilocked(struct binder_transaction * t,struct list_head * target_list)2805 binder_find_outdated_transaction_ilocked(struct binder_transaction *t,
2806 					 struct list_head *target_list)
2807 {
2808 	struct binder_work *w;
2809 
2810 	list_for_each_entry(w, target_list, entry) {
2811 		struct binder_transaction *t_queued;
2812 
2813 		if (w->type != BINDER_WORK_TRANSACTION)
2814 			continue;
2815 		t_queued = container_of(w, struct binder_transaction, work);
2816 		if (binder_can_update_transaction(t_queued, t))
2817 			return t_queued;
2818 	}
2819 	return NULL;
2820 }
2821 
2822 /**
2823  * binder_proc_transaction() - sends a transaction to a process and wakes it up
2824  * @t:		transaction to send
2825  * @proc:	process to send the transaction to
2826  * @thread:	thread in @proc to send the transaction to (may be NULL)
2827  *
2828  * This function queues a transaction to the specified process. It will try
2829  * to find a thread in the target process to handle the transaction and
2830  * wake it up. If no thread is found, the work is queued to the proc
2831  * waitqueue.
2832  *
2833  * If the @thread parameter is not NULL, the transaction is always queued
2834  * to the waitlist of that specific thread.
2835  *
2836  * Return:	0 if the transaction was successfully queued
2837  *		BR_DEAD_REPLY if the target process or thread is dead
2838  *		BR_FROZEN_REPLY if the target process or thread is frozen and
2839  *			the sync transaction was rejected
2840  *		BR_TRANSACTION_PENDING_FROZEN if the target process is frozen
2841  *		and the async transaction was successfully queued
2842  */
binder_proc_transaction(struct binder_transaction * t,struct binder_proc * proc,struct binder_thread * thread)2843 static int binder_proc_transaction(struct binder_transaction *t,
2844 				    struct binder_proc *proc,
2845 				    struct binder_thread *thread)
2846 {
2847 	struct binder_node *node = t->buffer->target_node;
2848 	bool oneway = !!(t->flags & TF_ONE_WAY);
2849 	bool pending_async = false;
2850 	struct binder_transaction *t_outdated = NULL;
2851 	bool frozen = false;
2852 
2853 	BUG_ON(!node);
2854 	binder_node_lock(node);
2855 	if (oneway) {
2856 		BUG_ON(thread);
2857 		if (node->has_async_transaction)
2858 			pending_async = true;
2859 		else
2860 			node->has_async_transaction = true;
2861 	}
2862 
2863 	binder_inner_proc_lock(proc);
2864 	if (proc->is_frozen) {
2865 		frozen = true;
2866 		proc->sync_recv |= !oneway;
2867 		proc->async_recv |= oneway;
2868 	}
2869 
2870 	if ((frozen && !oneway) || proc->is_dead ||
2871 			(thread && thread->is_dead)) {
2872 		binder_inner_proc_unlock(proc);
2873 		binder_node_unlock(node);
2874 		return frozen ? BR_FROZEN_REPLY : BR_DEAD_REPLY;
2875 	}
2876 
2877 	if (!thread && !pending_async)
2878 		thread = binder_select_thread_ilocked(proc);
2879 
2880 	if (thread) {
2881 		binder_enqueue_thread_work_ilocked(thread, &t->work);
2882 	} else if (!pending_async) {
2883 		binder_enqueue_work_ilocked(&t->work, &proc->todo);
2884 	} else {
2885 		if ((t->flags & TF_UPDATE_TXN) && frozen) {
2886 			t_outdated = binder_find_outdated_transaction_ilocked(t,
2887 									      &node->async_todo);
2888 			if (t_outdated) {
2889 				binder_debug(BINDER_DEBUG_TRANSACTION,
2890 					     "txn %d supersedes %d\n",
2891 					     t->debug_id, t_outdated->debug_id);
2892 				list_del_init(&t_outdated->work.entry);
2893 				proc->outstanding_txns--;
2894 			}
2895 		}
2896 		binder_enqueue_work_ilocked(&t->work, &node->async_todo);
2897 	}
2898 
2899 	if (!pending_async)
2900 		binder_wakeup_thread_ilocked(proc, thread, !oneway /* sync */);
2901 
2902 	proc->outstanding_txns++;
2903 	binder_inner_proc_unlock(proc);
2904 	binder_node_unlock(node);
2905 
2906 	/*
2907 	 * To reduce potential contention, free the outdated transaction and
2908 	 * buffer after releasing the locks.
2909 	 */
2910 	if (t_outdated) {
2911 		struct binder_buffer *buffer = t_outdated->buffer;
2912 
2913 		t_outdated->buffer = NULL;
2914 		buffer->transaction = NULL;
2915 		trace_binder_transaction_update_buffer_release(buffer);
2916 		binder_release_entire_buffer(proc, NULL, buffer, false);
2917 		binder_alloc_free_buf(&proc->alloc, buffer);
2918 		kfree(t_outdated);
2919 		binder_stats_deleted(BINDER_STAT_TRANSACTION);
2920 	}
2921 
2922 	if (oneway && frozen)
2923 		return BR_TRANSACTION_PENDING_FROZEN;
2924 
2925 	return 0;
2926 }
2927 
2928 /**
2929  * binder_get_node_refs_for_txn() - Get required refs on node for txn
2930  * @node:         struct binder_node for which to get refs
2931  * @procp:        returns @node->proc if valid
2932  * @error:        if no @procp then returns BR_DEAD_REPLY
2933  *
2934  * User-space normally keeps the node alive when creating a transaction
2935  * since it has a reference to the target. The local strong ref keeps it
2936  * alive if the sending process dies before the target process processes
2937  * the transaction. If the source process is malicious or has a reference
2938  * counting bug, relying on the local strong ref can fail.
2939  *
2940  * Since user-space can cause the local strong ref to go away, we also take
2941  * a tmpref on the node to ensure it survives while we are constructing
2942  * the transaction. We also need a tmpref on the proc while we are
2943  * constructing the transaction, so we take that here as well.
2944  *
2945  * Return: The target_node with refs taken or NULL if no @node->proc is NULL.
2946  * Also sets @procp if valid. If the @node->proc is NULL indicating that the
2947  * target proc has died, @error is set to BR_DEAD_REPLY.
2948  */
binder_get_node_refs_for_txn(struct binder_node * node,struct binder_proc ** procp,uint32_t * error)2949 static struct binder_node *binder_get_node_refs_for_txn(
2950 		struct binder_node *node,
2951 		struct binder_proc **procp,
2952 		uint32_t *error)
2953 {
2954 	struct binder_node *target_node = NULL;
2955 
2956 	binder_node_inner_lock(node);
2957 	if (node->proc) {
2958 		target_node = node;
2959 		binder_inc_node_nilocked(node, 1, 0, NULL);
2960 		binder_inc_node_tmpref_ilocked(node);
2961 		node->proc->tmp_ref++;
2962 		*procp = node->proc;
2963 	} else
2964 		*error = BR_DEAD_REPLY;
2965 	binder_node_inner_unlock(node);
2966 
2967 	return target_node;
2968 }
2969 
binder_set_txn_from_error(struct binder_transaction * t,int id,uint32_t command,int32_t param)2970 static void binder_set_txn_from_error(struct binder_transaction *t, int id,
2971 				      uint32_t command, int32_t param)
2972 {
2973 	struct binder_thread *from = binder_get_txn_from_and_acq_inner(t);
2974 
2975 	if (!from) {
2976 		/* annotation for sparse */
2977 		__release(&from->proc->inner_lock);
2978 		return;
2979 	}
2980 
2981 	/* don't override existing errors */
2982 	if (from->ee.command == BR_OK)
2983 		binder_set_extended_error(&from->ee, id, command, param);
2984 	binder_inner_proc_unlock(from->proc);
2985 	binder_thread_dec_tmpref(from);
2986 }
2987 
2988 /**
2989  * binder_netlink_report() - report a transaction failure via netlink
2990  * @proc:	the binder proc sending the transaction
2991  * @t:		the binder transaction that failed
2992  * @data_size:	the user provided data size for the transaction
2993  * @error:	enum binder_driver_return_protocol returned to sender
2994  */
binder_netlink_report(struct binder_proc * proc,struct binder_transaction * t,u32 data_size,u32 error)2995 static void binder_netlink_report(struct binder_proc *proc,
2996 				  struct binder_transaction *t,
2997 				  u32 data_size,
2998 				  u32 error)
2999 {
3000 	const char *context = proc->context->name;
3001 	struct sk_buff *skb;
3002 	void *hdr;
3003 
3004 	if (!genl_has_listeners(&binder_nl_family, &init_net,
3005 				BINDER_NLGRP_REPORT))
3006 		return;
3007 
3008 	trace_binder_netlink_report(context, t, data_size, error);
3009 
3010 	skb = genlmsg_new(GENLMSG_DEFAULT_SIZE, GFP_KERNEL);
3011 	if (!skb)
3012 		return;
3013 
3014 	hdr = genlmsg_put(skb, 0, 0, &binder_nl_family, 0, BINDER_CMD_REPORT);
3015 	if (!hdr)
3016 		goto free_skb;
3017 
3018 	if (nla_put_u32(skb, BINDER_A_REPORT_ERROR, error) ||
3019 	    nla_put_string(skb, BINDER_A_REPORT_CONTEXT, context) ||
3020 	    nla_put_u32(skb, BINDER_A_REPORT_FROM_PID, t->from_pid) ||
3021 	    nla_put_u32(skb, BINDER_A_REPORT_FROM_TID, t->from_tid))
3022 		goto cancel_skb;
3023 
3024 	if (t->to_proc &&
3025 	    nla_put_u32(skb, BINDER_A_REPORT_TO_PID, t->to_proc->pid))
3026 		goto cancel_skb;
3027 
3028 	if (t->to_thread &&
3029 	    nla_put_u32(skb, BINDER_A_REPORT_TO_TID, t->to_thread->pid))
3030 		goto cancel_skb;
3031 
3032 	if (t->is_reply && nla_put_flag(skb, BINDER_A_REPORT_IS_REPLY))
3033 		goto cancel_skb;
3034 
3035 	if (nla_put_u32(skb, BINDER_A_REPORT_FLAGS, t->flags) ||
3036 	    nla_put_u32(skb, BINDER_A_REPORT_CODE, t->code) ||
3037 	    nla_put_u32(skb, BINDER_A_REPORT_DATA_SIZE, data_size))
3038 		goto cancel_skb;
3039 
3040 	genlmsg_end(skb, hdr);
3041 	genlmsg_multicast(&binder_nl_family, skb, 0, BINDER_NLGRP_REPORT,
3042 			  GFP_KERNEL);
3043 	return;
3044 
3045 cancel_skb:
3046 	genlmsg_cancel(skb, hdr);
3047 free_skb:
3048 	nlmsg_free(skb);
3049 }
3050 
binder_transaction(struct binder_proc * proc,struct binder_thread * thread,struct binder_transaction_data * tr,int reply,binder_size_t extra_buffers_size)3051 static void binder_transaction(struct binder_proc *proc,
3052 			       struct binder_thread *thread,
3053 			       struct binder_transaction_data *tr, int reply,
3054 			       binder_size_t extra_buffers_size)
3055 {
3056 	int ret;
3057 	struct binder_transaction *t;
3058 	struct binder_work *w;
3059 	struct binder_work *tcomplete;
3060 	binder_size_t buffer_offset = 0;
3061 	binder_size_t off_start_offset, off_end_offset;
3062 	binder_size_t off_min;
3063 	binder_size_t sg_buf_offset, sg_buf_end_offset;
3064 	binder_size_t user_offset = 0;
3065 	struct binder_proc *target_proc = NULL;
3066 	struct binder_thread *target_thread = NULL;
3067 	struct binder_node *target_node = NULL;
3068 	struct binder_transaction *in_reply_to = NULL;
3069 	struct binder_transaction_log_entry *e;
3070 	uint32_t return_error = 0;
3071 	uint32_t return_error_param = 0;
3072 	uint32_t return_error_line = 0;
3073 	binder_size_t last_fixup_obj_off = 0;
3074 	binder_size_t last_fixup_min_off = 0;
3075 	struct binder_context *context = proc->context;
3076 	int t_debug_id = atomic_inc_return(&binder_last_id);
3077 	ktime_t t_start_time = ktime_get();
3078 	struct lsm_context lsmctx = { };
3079 	struct list_head sgc_head;
3080 	struct list_head pf_head;
3081 	const void __user *user_buffer = (const void __user *)
3082 				(uintptr_t)tr->data.ptr.buffer;
3083 	INIT_LIST_HEAD(&sgc_head);
3084 	INIT_LIST_HEAD(&pf_head);
3085 
3086 	e = binder_transaction_log_add(&binder_transaction_log);
3087 	e->debug_id = t_debug_id;
3088 	e->call_type = reply ? 2 : !!(tr->flags & TF_ONE_WAY);
3089 	e->from_proc = proc->pid;
3090 	e->from_thread = thread->pid;
3091 	e->target_handle = tr->target.handle;
3092 	e->data_size = tr->data_size;
3093 	e->offsets_size = tr->offsets_size;
3094 	strscpy(e->context_name, proc->context->name, BINDERFS_MAX_NAME);
3095 
3096 	binder_inner_proc_lock(proc);
3097 	binder_set_extended_error(&thread->ee, t_debug_id, BR_OK, 0);
3098 	binder_inner_proc_unlock(proc);
3099 
3100 	t = kzalloc(sizeof(*t), GFP_KERNEL);
3101 	if (!t) {
3102 		binder_txn_error("%d:%d cannot allocate transaction\n",
3103 				 thread->pid, proc->pid);
3104 		return_error = BR_FAILED_REPLY;
3105 		return_error_param = -ENOMEM;
3106 		return_error_line = __LINE__;
3107 		goto err_alloc_t_failed;
3108 	}
3109 	INIT_LIST_HEAD(&t->fd_fixups);
3110 	binder_stats_created(BINDER_STAT_TRANSACTION);
3111 	spin_lock_init(&t->lock);
3112 	t->debug_id = t_debug_id;
3113 	t->start_time = t_start_time;
3114 	t->from_pid = proc->pid;
3115 	t->from_tid = thread->pid;
3116 	t->sender_euid = task_euid(proc->tsk);
3117 	t->code = tr->code;
3118 	t->flags = tr->flags;
3119 	t->priority = task_nice(current);
3120 	t->work.type = BINDER_WORK_TRANSACTION;
3121 	t->is_async = !reply && (tr->flags & TF_ONE_WAY);
3122 	t->is_reply = reply;
3123 	if (!reply && !(tr->flags & TF_ONE_WAY))
3124 		t->from = thread;
3125 
3126 	if (reply) {
3127 		binder_inner_proc_lock(proc);
3128 		in_reply_to = thread->transaction_stack;
3129 		if (in_reply_to == NULL) {
3130 			binder_inner_proc_unlock(proc);
3131 			binder_user_error("%d:%d got reply transaction with no transaction stack\n",
3132 					  proc->pid, thread->pid);
3133 			return_error = BR_FAILED_REPLY;
3134 			return_error_param = -EPROTO;
3135 			return_error_line = __LINE__;
3136 			goto err_empty_call_stack;
3137 		}
3138 		if (in_reply_to->to_thread != thread) {
3139 			spin_lock(&in_reply_to->lock);
3140 			binder_user_error("%d:%d got reply transaction with bad transaction stack, transaction %d has target %d:%d\n",
3141 				proc->pid, thread->pid, in_reply_to->debug_id,
3142 				in_reply_to->to_proc ?
3143 				in_reply_to->to_proc->pid : 0,
3144 				in_reply_to->to_thread ?
3145 				in_reply_to->to_thread->pid : 0);
3146 			spin_unlock(&in_reply_to->lock);
3147 			binder_inner_proc_unlock(proc);
3148 			return_error = BR_FAILED_REPLY;
3149 			return_error_param = -EPROTO;
3150 			return_error_line = __LINE__;
3151 			in_reply_to = NULL;
3152 			goto err_bad_call_stack;
3153 		}
3154 		thread->transaction_stack = in_reply_to->to_parent;
3155 		binder_inner_proc_unlock(proc);
3156 		binder_set_nice(in_reply_to->saved_priority);
3157 		target_thread = binder_get_txn_from_and_acq_inner(in_reply_to);
3158 		if (target_thread == NULL) {
3159 			/* annotation for sparse */
3160 			__release(&target_thread->proc->inner_lock);
3161 			binder_txn_error("%d:%d reply target not found\n",
3162 				thread->pid, proc->pid);
3163 			return_error = BR_DEAD_REPLY;
3164 			return_error_line = __LINE__;
3165 			goto err_dead_binder;
3166 		}
3167 		if (target_thread->transaction_stack != in_reply_to) {
3168 			binder_user_error("%d:%d got reply transaction with bad target transaction stack %d, expected %d\n",
3169 				proc->pid, thread->pid,
3170 				target_thread->transaction_stack ?
3171 				target_thread->transaction_stack->debug_id : 0,
3172 				in_reply_to->debug_id);
3173 			binder_inner_proc_unlock(target_thread->proc);
3174 			return_error = BR_FAILED_REPLY;
3175 			return_error_param = -EPROTO;
3176 			return_error_line = __LINE__;
3177 			in_reply_to = NULL;
3178 			target_thread = NULL;
3179 			goto err_dead_binder;
3180 		}
3181 		target_proc = target_thread->proc;
3182 		target_proc->tmp_ref++;
3183 		binder_inner_proc_unlock(target_thread->proc);
3184 	} else {
3185 		if (tr->target.handle) {
3186 			struct binder_ref *ref;
3187 
3188 			/*
3189 			 * There must already be a strong ref
3190 			 * on this node. If so, do a strong
3191 			 * increment on the node to ensure it
3192 			 * stays alive until the transaction is
3193 			 * done.
3194 			 */
3195 			binder_proc_lock(proc);
3196 			ref = binder_get_ref_olocked(proc, tr->target.handle,
3197 						     true);
3198 			if (ref) {
3199 				target_node = binder_get_node_refs_for_txn(
3200 						ref->node, &target_proc,
3201 						&return_error);
3202 			} else {
3203 				binder_user_error("%d:%d got transaction to invalid handle, %u\n",
3204 						  proc->pid, thread->pid, tr->target.handle);
3205 				return_error = BR_FAILED_REPLY;
3206 			}
3207 			binder_proc_unlock(proc);
3208 		} else {
3209 			mutex_lock(&context->context_mgr_node_lock);
3210 			target_node = context->binder_context_mgr_node;
3211 			if (target_node)
3212 				target_node = binder_get_node_refs_for_txn(
3213 						target_node, &target_proc,
3214 						&return_error);
3215 			else
3216 				return_error = BR_DEAD_REPLY;
3217 			mutex_unlock(&context->context_mgr_node_lock);
3218 			if (target_node && target_proc->pid == proc->pid) {
3219 				binder_user_error("%d:%d got transaction to context manager from process owning it\n",
3220 						  proc->pid, thread->pid);
3221 				return_error = BR_FAILED_REPLY;
3222 				return_error_param = -EINVAL;
3223 				return_error_line = __LINE__;
3224 				goto err_invalid_target_handle;
3225 			}
3226 		}
3227 		if (!target_node) {
3228 			binder_txn_error("%d:%d cannot find target node\n",
3229 					 proc->pid, thread->pid);
3230 			/* return_error is set above */
3231 			return_error_param = -EINVAL;
3232 			return_error_line = __LINE__;
3233 			goto err_dead_binder;
3234 		}
3235 		e->to_node = target_node->debug_id;
3236 		if (WARN_ON(proc == target_proc)) {
3237 			binder_txn_error("%d:%d self transactions not allowed\n",
3238 				thread->pid, proc->pid);
3239 			return_error = BR_FAILED_REPLY;
3240 			return_error_param = -EINVAL;
3241 			return_error_line = __LINE__;
3242 			goto err_invalid_target_handle;
3243 		}
3244 		if (security_binder_transaction(proc->cred,
3245 						target_proc->cred) < 0) {
3246 			binder_txn_error("%d:%d transaction credentials failed\n",
3247 				thread->pid, proc->pid);
3248 			return_error = BR_FAILED_REPLY;
3249 			return_error_param = -EPERM;
3250 			return_error_line = __LINE__;
3251 			goto err_invalid_target_handle;
3252 		}
3253 		binder_inner_proc_lock(proc);
3254 
3255 		w = list_first_entry_or_null(&thread->todo,
3256 					     struct binder_work, entry);
3257 		if (!(tr->flags & TF_ONE_WAY) && w &&
3258 		    w->type == BINDER_WORK_TRANSACTION) {
3259 			/*
3260 			 * Do not allow new outgoing transaction from a
3261 			 * thread that has a transaction at the head of
3262 			 * its todo list. Only need to check the head
3263 			 * because binder_select_thread_ilocked picks a
3264 			 * thread from proc->waiting_threads to enqueue
3265 			 * the transaction, and nothing is queued to the
3266 			 * todo list while the thread is on waiting_threads.
3267 			 */
3268 			binder_user_error("%d:%d new transaction not allowed when there is a transaction on thread todo\n",
3269 					  proc->pid, thread->pid);
3270 			binder_inner_proc_unlock(proc);
3271 			return_error = BR_FAILED_REPLY;
3272 			return_error_param = -EPROTO;
3273 			return_error_line = __LINE__;
3274 			goto err_bad_todo_list;
3275 		}
3276 
3277 		if (!(tr->flags & TF_ONE_WAY) && thread->transaction_stack) {
3278 			struct binder_transaction *tmp;
3279 
3280 			tmp = thread->transaction_stack;
3281 			if (tmp->to_thread != thread) {
3282 				spin_lock(&tmp->lock);
3283 				binder_user_error("%d:%d got new transaction with bad transaction stack, transaction %d has target %d:%d\n",
3284 					proc->pid, thread->pid, tmp->debug_id,
3285 					tmp->to_proc ? tmp->to_proc->pid : 0,
3286 					tmp->to_thread ?
3287 					tmp->to_thread->pid : 0);
3288 				spin_unlock(&tmp->lock);
3289 				binder_inner_proc_unlock(proc);
3290 				return_error = BR_FAILED_REPLY;
3291 				return_error_param = -EPROTO;
3292 				return_error_line = __LINE__;
3293 				goto err_bad_call_stack;
3294 			}
3295 			while (tmp) {
3296 				struct binder_thread *from;
3297 
3298 				spin_lock(&tmp->lock);
3299 				from = tmp->from;
3300 				if (from && from->proc == target_proc) {
3301 					atomic_inc(&from->tmp_ref);
3302 					target_thread = from;
3303 					spin_unlock(&tmp->lock);
3304 					break;
3305 				}
3306 				spin_unlock(&tmp->lock);
3307 				tmp = tmp->from_parent;
3308 			}
3309 		}
3310 		binder_inner_proc_unlock(proc);
3311 	}
3312 
3313 	t->to_proc = target_proc;
3314 	t->to_thread = target_thread;
3315 	if (target_thread)
3316 		e->to_thread = target_thread->pid;
3317 	e->to_proc = target_proc->pid;
3318 
3319 	tcomplete = kzalloc(sizeof(*tcomplete), GFP_KERNEL);
3320 	if (tcomplete == NULL) {
3321 		binder_txn_error("%d:%d cannot allocate work for transaction\n",
3322 			thread->pid, proc->pid);
3323 		return_error = BR_FAILED_REPLY;
3324 		return_error_param = -ENOMEM;
3325 		return_error_line = __LINE__;
3326 		goto err_alloc_tcomplete_failed;
3327 	}
3328 	binder_stats_created(BINDER_STAT_TRANSACTION_COMPLETE);
3329 
3330 	if (reply)
3331 		binder_debug(BINDER_DEBUG_TRANSACTION,
3332 			     "%d:%d BC_REPLY %d -> %d:%d, data size %lld-%lld-%lld\n",
3333 			     proc->pid, thread->pid, t->debug_id,
3334 			     target_proc->pid, target_thread->pid,
3335 			     (u64)tr->data_size, (u64)tr->offsets_size,
3336 			     (u64)extra_buffers_size);
3337 	else
3338 		binder_debug(BINDER_DEBUG_TRANSACTION,
3339 			     "%d:%d BC_TRANSACTION %d -> %d - node %d, data size %lld-%lld-%lld\n",
3340 			     proc->pid, thread->pid, t->debug_id,
3341 			     target_proc->pid, target_node->debug_id,
3342 			     (u64)tr->data_size, (u64)tr->offsets_size,
3343 			     (u64)extra_buffers_size);
3344 
3345 	if (target_node && target_node->txn_security_ctx) {
3346 		u32 secid;
3347 		size_t added_size;
3348 
3349 		security_cred_getsecid(proc->cred, &secid);
3350 		ret = security_secid_to_secctx(secid, &lsmctx);
3351 		if (ret < 0) {
3352 			binder_txn_error("%d:%d failed to get security context\n",
3353 				thread->pid, proc->pid);
3354 			return_error = BR_FAILED_REPLY;
3355 			return_error_param = ret;
3356 			return_error_line = __LINE__;
3357 			goto err_get_secctx_failed;
3358 		}
3359 		added_size = ALIGN(lsmctx.len, sizeof(u64));
3360 		extra_buffers_size += added_size;
3361 		if (extra_buffers_size < added_size) {
3362 			binder_txn_error("%d:%d integer overflow of extra_buffers_size\n",
3363 				thread->pid, proc->pid);
3364 			return_error = BR_FAILED_REPLY;
3365 			return_error_param = -EINVAL;
3366 			return_error_line = __LINE__;
3367 			goto err_bad_extra_size;
3368 		}
3369 	}
3370 
3371 	trace_binder_transaction(reply, t, target_node);
3372 
3373 	t->buffer = binder_alloc_new_buf(&target_proc->alloc, tr->data_size,
3374 		tr->offsets_size, extra_buffers_size,
3375 		!reply && (t->flags & TF_ONE_WAY));
3376 	if (IS_ERR(t->buffer)) {
3377 		char *s;
3378 
3379 		ret = PTR_ERR(t->buffer);
3380 		s = (ret == -ESRCH) ? ": vma cleared, target dead or dying"
3381 			: (ret == -ENOSPC) ? ": no space left"
3382 			: (ret == -ENOMEM) ? ": memory allocation failed"
3383 			: "";
3384 		binder_txn_error("cannot allocate buffer%s", s);
3385 
3386 		return_error_param = PTR_ERR(t->buffer);
3387 		return_error = return_error_param == -ESRCH ?
3388 			BR_DEAD_REPLY : BR_FAILED_REPLY;
3389 		return_error_line = __LINE__;
3390 		t->buffer = NULL;
3391 		goto err_binder_alloc_buf_failed;
3392 	}
3393 	if (lsmctx.context) {
3394 		int err;
3395 		size_t buf_offset = ALIGN(tr->data_size, sizeof(void *)) +
3396 				    ALIGN(tr->offsets_size, sizeof(void *)) +
3397 				    ALIGN(extra_buffers_size, sizeof(void *)) -
3398 				    ALIGN(lsmctx.len, sizeof(u64));
3399 
3400 		t->security_ctx = t->buffer->user_data + buf_offset;
3401 		err = binder_alloc_copy_to_buffer(&target_proc->alloc,
3402 						  t->buffer, buf_offset,
3403 						  lsmctx.context, lsmctx.len);
3404 		if (err) {
3405 			t->security_ctx = 0;
3406 			WARN_ON(1);
3407 		}
3408 		security_release_secctx(&lsmctx);
3409 		lsmctx.context = NULL;
3410 	}
3411 	t->buffer->debug_id = t->debug_id;
3412 	t->buffer->transaction = t;
3413 	t->buffer->target_node = target_node;
3414 	t->buffer->clear_on_free = !!(t->flags & TF_CLEAR_BUF);
3415 	trace_binder_transaction_alloc_buf(t->buffer);
3416 
3417 	if (binder_alloc_copy_user_to_buffer(
3418 				&target_proc->alloc,
3419 				t->buffer,
3420 				ALIGN(tr->data_size, sizeof(void *)),
3421 				(const void __user *)
3422 					(uintptr_t)tr->data.ptr.offsets,
3423 				tr->offsets_size)) {
3424 		binder_user_error("%d:%d got transaction with invalid offsets ptr\n",
3425 				proc->pid, thread->pid);
3426 		return_error = BR_FAILED_REPLY;
3427 		return_error_param = -EFAULT;
3428 		return_error_line = __LINE__;
3429 		goto err_copy_data_failed;
3430 	}
3431 	if (!IS_ALIGNED(tr->offsets_size, sizeof(binder_size_t))) {
3432 		binder_user_error("%d:%d got transaction with invalid offsets size, %lld\n",
3433 				proc->pid, thread->pid, (u64)tr->offsets_size);
3434 		return_error = BR_FAILED_REPLY;
3435 		return_error_param = -EINVAL;
3436 		return_error_line = __LINE__;
3437 		goto err_bad_offset;
3438 	}
3439 	if (!IS_ALIGNED(extra_buffers_size, sizeof(u64))) {
3440 		binder_user_error("%d:%d got transaction with unaligned buffers size, %lld\n",
3441 				  proc->pid, thread->pid,
3442 				  (u64)extra_buffers_size);
3443 		return_error = BR_FAILED_REPLY;
3444 		return_error_param = -EINVAL;
3445 		return_error_line = __LINE__;
3446 		goto err_bad_offset;
3447 	}
3448 	off_start_offset = ALIGN(tr->data_size, sizeof(void *));
3449 	buffer_offset = off_start_offset;
3450 	off_end_offset = off_start_offset + tr->offsets_size;
3451 	sg_buf_offset = ALIGN(off_end_offset, sizeof(void *));
3452 	sg_buf_end_offset = sg_buf_offset + extra_buffers_size -
3453 		ALIGN(lsmctx.len, sizeof(u64));
3454 	off_min = 0;
3455 	for (buffer_offset = off_start_offset; buffer_offset < off_end_offset;
3456 	     buffer_offset += sizeof(binder_size_t)) {
3457 		struct binder_object_header *hdr;
3458 		size_t object_size;
3459 		struct binder_object object;
3460 		binder_size_t object_offset;
3461 		binder_size_t copy_size;
3462 
3463 		if (binder_alloc_copy_from_buffer(&target_proc->alloc,
3464 						  &object_offset,
3465 						  t->buffer,
3466 						  buffer_offset,
3467 						  sizeof(object_offset))) {
3468 			binder_txn_error("%d:%d copy offset from buffer failed\n",
3469 				thread->pid, proc->pid);
3470 			return_error = BR_FAILED_REPLY;
3471 			return_error_param = -EINVAL;
3472 			return_error_line = __LINE__;
3473 			goto err_bad_offset;
3474 		}
3475 
3476 		/*
3477 		 * Copy the source user buffer up to the next object
3478 		 * that will be processed.
3479 		 */
3480 		copy_size = object_offset - user_offset;
3481 		if (copy_size && (user_offset > object_offset ||
3482 				object_offset > tr->data_size ||
3483 				binder_alloc_copy_user_to_buffer(
3484 					&target_proc->alloc,
3485 					t->buffer, user_offset,
3486 					user_buffer + user_offset,
3487 					copy_size))) {
3488 			binder_user_error("%d:%d got transaction with invalid data ptr\n",
3489 					proc->pid, thread->pid);
3490 			return_error = BR_FAILED_REPLY;
3491 			return_error_param = -EFAULT;
3492 			return_error_line = __LINE__;
3493 			goto err_copy_data_failed;
3494 		}
3495 		object_size = binder_get_object(target_proc, user_buffer,
3496 				t->buffer, object_offset, &object);
3497 		if (object_size == 0 || object_offset < off_min) {
3498 			binder_user_error("%d:%d got transaction with invalid offset (%lld, min %lld max %lld) or object.\n",
3499 					  proc->pid, thread->pid,
3500 					  (u64)object_offset,
3501 					  (u64)off_min,
3502 					  (u64)t->buffer->data_size);
3503 			return_error = BR_FAILED_REPLY;
3504 			return_error_param = -EINVAL;
3505 			return_error_line = __LINE__;
3506 			goto err_bad_offset;
3507 		}
3508 		/*
3509 		 * Set offset to the next buffer fragment to be
3510 		 * copied
3511 		 */
3512 		user_offset = object_offset + object_size;
3513 
3514 		hdr = &object.hdr;
3515 		off_min = object_offset + object_size;
3516 		switch (hdr->type) {
3517 		case BINDER_TYPE_BINDER:
3518 		case BINDER_TYPE_WEAK_BINDER: {
3519 			struct flat_binder_object *fp;
3520 
3521 			fp = to_flat_binder_object(hdr);
3522 			ret = binder_translate_binder(fp, t, thread);
3523 
3524 			if (ret < 0 ||
3525 			    binder_alloc_copy_to_buffer(&target_proc->alloc,
3526 							t->buffer,
3527 							object_offset,
3528 							fp, sizeof(*fp))) {
3529 				binder_txn_error("%d:%d translate binder failed\n",
3530 					thread->pid, proc->pid);
3531 				return_error = BR_FAILED_REPLY;
3532 				return_error_param = ret;
3533 				return_error_line = __LINE__;
3534 				goto err_translate_failed;
3535 			}
3536 		} break;
3537 		case BINDER_TYPE_HANDLE:
3538 		case BINDER_TYPE_WEAK_HANDLE: {
3539 			struct flat_binder_object *fp;
3540 
3541 			fp = to_flat_binder_object(hdr);
3542 			ret = binder_translate_handle(fp, t, thread);
3543 			if (ret < 0 ||
3544 			    binder_alloc_copy_to_buffer(&target_proc->alloc,
3545 							t->buffer,
3546 							object_offset,
3547 							fp, sizeof(*fp))) {
3548 				binder_txn_error("%d:%d translate handle failed\n",
3549 					thread->pid, proc->pid);
3550 				return_error = BR_FAILED_REPLY;
3551 				return_error_param = ret;
3552 				return_error_line = __LINE__;
3553 				goto err_translate_failed;
3554 			}
3555 		} break;
3556 
3557 		case BINDER_TYPE_FD: {
3558 			struct binder_fd_object *fp = to_binder_fd_object(hdr);
3559 			binder_size_t fd_offset = object_offset +
3560 				(uintptr_t)&fp->fd - (uintptr_t)fp;
3561 			int ret = binder_translate_fd(fp->fd, fd_offset, t,
3562 						      thread, in_reply_to);
3563 
3564 			fp->pad_binder = 0;
3565 			if (ret < 0 ||
3566 			    binder_alloc_copy_to_buffer(&target_proc->alloc,
3567 							t->buffer,
3568 							object_offset,
3569 							fp, sizeof(*fp))) {
3570 				binder_txn_error("%d:%d translate fd failed\n",
3571 					thread->pid, proc->pid);
3572 				return_error = BR_FAILED_REPLY;
3573 				return_error_param = ret;
3574 				return_error_line = __LINE__;
3575 				goto err_translate_failed;
3576 			}
3577 		} break;
3578 		case BINDER_TYPE_FDA: {
3579 			struct binder_object ptr_object;
3580 			binder_size_t parent_offset;
3581 			struct binder_object user_object;
3582 			size_t user_parent_size;
3583 			struct binder_fd_array_object *fda =
3584 				to_binder_fd_array_object(hdr);
3585 			size_t num_valid = (buffer_offset - off_start_offset) /
3586 						sizeof(binder_size_t);
3587 			struct binder_buffer_object *parent =
3588 				binder_validate_ptr(target_proc, t->buffer,
3589 						    &ptr_object, fda->parent,
3590 						    off_start_offset,
3591 						    &parent_offset,
3592 						    num_valid);
3593 			if (!parent) {
3594 				binder_user_error("%d:%d got transaction with invalid parent offset or type\n",
3595 						  proc->pid, thread->pid);
3596 				return_error = BR_FAILED_REPLY;
3597 				return_error_param = -EINVAL;
3598 				return_error_line = __LINE__;
3599 				goto err_bad_parent;
3600 			}
3601 			if (!binder_validate_fixup(target_proc, t->buffer,
3602 						   off_start_offset,
3603 						   parent_offset,
3604 						   fda->parent_offset,
3605 						   last_fixup_obj_off,
3606 						   last_fixup_min_off)) {
3607 				binder_user_error("%d:%d got transaction with out-of-order buffer fixup\n",
3608 						  proc->pid, thread->pid);
3609 				return_error = BR_FAILED_REPLY;
3610 				return_error_param = -EINVAL;
3611 				return_error_line = __LINE__;
3612 				goto err_bad_parent;
3613 			}
3614 			/*
3615 			 * We need to read the user version of the parent
3616 			 * object to get the original user offset
3617 			 */
3618 			user_parent_size =
3619 				binder_get_object(proc, user_buffer, t->buffer,
3620 						  parent_offset, &user_object);
3621 			if (user_parent_size != sizeof(user_object.bbo)) {
3622 				binder_user_error("%d:%d invalid ptr object size: %zd vs %zd\n",
3623 						  proc->pid, thread->pid,
3624 						  user_parent_size,
3625 						  sizeof(user_object.bbo));
3626 				return_error = BR_FAILED_REPLY;
3627 				return_error_param = -EINVAL;
3628 				return_error_line = __LINE__;
3629 				goto err_bad_parent;
3630 			}
3631 			ret = binder_translate_fd_array(&pf_head, fda,
3632 							user_buffer, parent,
3633 							&user_object.bbo, t,
3634 							thread, in_reply_to);
3635 			if (!ret)
3636 				ret = binder_alloc_copy_to_buffer(&target_proc->alloc,
3637 								  t->buffer,
3638 								  object_offset,
3639 								  fda, sizeof(*fda));
3640 			if (ret) {
3641 				binder_txn_error("%d:%d translate fd array failed\n",
3642 					thread->pid, proc->pid);
3643 				return_error = BR_FAILED_REPLY;
3644 				return_error_param = ret > 0 ? -EINVAL : ret;
3645 				return_error_line = __LINE__;
3646 				goto err_translate_failed;
3647 			}
3648 			last_fixup_obj_off = parent_offset;
3649 			last_fixup_min_off =
3650 				fda->parent_offset + sizeof(u32) * fda->num_fds;
3651 		} break;
3652 		case BINDER_TYPE_PTR: {
3653 			struct binder_buffer_object *bp =
3654 				to_binder_buffer_object(hdr);
3655 			size_t buf_left = sg_buf_end_offset - sg_buf_offset;
3656 			size_t num_valid;
3657 
3658 			if (bp->length > buf_left) {
3659 				binder_user_error("%d:%d got transaction with too large buffer\n",
3660 						  proc->pid, thread->pid);
3661 				return_error = BR_FAILED_REPLY;
3662 				return_error_param = -EINVAL;
3663 				return_error_line = __LINE__;
3664 				goto err_bad_offset;
3665 			}
3666 			ret = binder_defer_copy(&sgc_head, sg_buf_offset,
3667 				(const void __user *)(uintptr_t)bp->buffer,
3668 				bp->length);
3669 			if (ret) {
3670 				binder_txn_error("%d:%d deferred copy failed\n",
3671 					thread->pid, proc->pid);
3672 				return_error = BR_FAILED_REPLY;
3673 				return_error_param = ret;
3674 				return_error_line = __LINE__;
3675 				goto err_translate_failed;
3676 			}
3677 			/* Fixup buffer pointer to target proc address space */
3678 			bp->buffer = t->buffer->user_data + sg_buf_offset;
3679 			sg_buf_offset += ALIGN(bp->length, sizeof(u64));
3680 
3681 			num_valid = (buffer_offset - off_start_offset) /
3682 					sizeof(binder_size_t);
3683 			ret = binder_fixup_parent(&pf_head, t,
3684 						  thread, bp,
3685 						  off_start_offset,
3686 						  num_valid,
3687 						  last_fixup_obj_off,
3688 						  last_fixup_min_off);
3689 			if (ret < 0 ||
3690 			    binder_alloc_copy_to_buffer(&target_proc->alloc,
3691 							t->buffer,
3692 							object_offset,
3693 							bp, sizeof(*bp))) {
3694 				binder_txn_error("%d:%d failed to fixup parent\n",
3695 					thread->pid, proc->pid);
3696 				return_error = BR_FAILED_REPLY;
3697 				return_error_param = ret;
3698 				return_error_line = __LINE__;
3699 				goto err_translate_failed;
3700 			}
3701 			last_fixup_obj_off = object_offset;
3702 			last_fixup_min_off = 0;
3703 		} break;
3704 		default:
3705 			binder_user_error("%d:%d got transaction with invalid object type, %x\n",
3706 				proc->pid, thread->pid, hdr->type);
3707 			return_error = BR_FAILED_REPLY;
3708 			return_error_param = -EINVAL;
3709 			return_error_line = __LINE__;
3710 			goto err_bad_object_type;
3711 		}
3712 	}
3713 	/* Done processing objects, copy the rest of the buffer */
3714 	if (binder_alloc_copy_user_to_buffer(
3715 				&target_proc->alloc,
3716 				t->buffer, user_offset,
3717 				user_buffer + user_offset,
3718 				tr->data_size - user_offset)) {
3719 		binder_user_error("%d:%d got transaction with invalid data ptr\n",
3720 				proc->pid, thread->pid);
3721 		return_error = BR_FAILED_REPLY;
3722 		return_error_param = -EFAULT;
3723 		return_error_line = __LINE__;
3724 		goto err_copy_data_failed;
3725 	}
3726 
3727 	ret = binder_do_deferred_txn_copies(&target_proc->alloc, t->buffer,
3728 					    &sgc_head, &pf_head);
3729 	if (ret) {
3730 		binder_user_error("%d:%d got transaction with invalid offsets ptr\n",
3731 				  proc->pid, thread->pid);
3732 		return_error = BR_FAILED_REPLY;
3733 		return_error_param = ret;
3734 		return_error_line = __LINE__;
3735 		goto err_copy_data_failed;
3736 	}
3737 	if (t->buffer->oneway_spam_suspect) {
3738 		tcomplete->type = BINDER_WORK_TRANSACTION_ONEWAY_SPAM_SUSPECT;
3739 		binder_netlink_report(proc, t, tr->data_size,
3740 				      BR_ONEWAY_SPAM_SUSPECT);
3741 	} else {
3742 		tcomplete->type = BINDER_WORK_TRANSACTION_COMPLETE;
3743 	}
3744 
3745 	if (reply) {
3746 		binder_enqueue_thread_work(thread, tcomplete);
3747 		binder_inner_proc_lock(target_proc);
3748 		if (target_thread->is_dead) {
3749 			return_error = BR_DEAD_REPLY;
3750 			binder_inner_proc_unlock(target_proc);
3751 			goto err_dead_proc_or_thread;
3752 		}
3753 		BUG_ON(t->buffer->async_transaction != 0);
3754 		binder_pop_transaction_ilocked(target_thread, in_reply_to);
3755 		binder_enqueue_thread_work_ilocked(target_thread, &t->work);
3756 		target_proc->outstanding_txns++;
3757 		binder_inner_proc_unlock(target_proc);
3758 		wake_up_interruptible_sync(&target_thread->wait);
3759 		binder_free_transaction(in_reply_to);
3760 	} else if (!(t->flags & TF_ONE_WAY)) {
3761 		BUG_ON(t->buffer->async_transaction != 0);
3762 		binder_inner_proc_lock(proc);
3763 		/*
3764 		 * Defer the TRANSACTION_COMPLETE, so we don't return to
3765 		 * userspace immediately; this allows the target process to
3766 		 * immediately start processing this transaction, reducing
3767 		 * latency. We will then return the TRANSACTION_COMPLETE when
3768 		 * the target replies (or there is an error).
3769 		 */
3770 		binder_enqueue_deferred_thread_work_ilocked(thread, tcomplete);
3771 		t->from_parent = thread->transaction_stack;
3772 		thread->transaction_stack = t;
3773 		binder_inner_proc_unlock(proc);
3774 		return_error = binder_proc_transaction(t,
3775 				target_proc, target_thread);
3776 		if (return_error) {
3777 			binder_inner_proc_lock(proc);
3778 			binder_pop_transaction_ilocked(thread, t);
3779 			binder_inner_proc_unlock(proc);
3780 			goto err_dead_proc_or_thread;
3781 		}
3782 	} else {
3783 		BUG_ON(target_node == NULL);
3784 		BUG_ON(t->buffer->async_transaction != 1);
3785 		return_error = binder_proc_transaction(t, target_proc, NULL);
3786 		/*
3787 		 * Let the caller know when async transaction reaches a frozen
3788 		 * process and is put in a pending queue, waiting for the target
3789 		 * process to be unfrozen.
3790 		 */
3791 		if (return_error == BR_TRANSACTION_PENDING_FROZEN) {
3792 			tcomplete->type = BINDER_WORK_TRANSACTION_PENDING;
3793 			binder_netlink_report(proc, t, tr->data_size,
3794 					      return_error);
3795 		}
3796 		binder_enqueue_thread_work(thread, tcomplete);
3797 		if (return_error &&
3798 		    return_error != BR_TRANSACTION_PENDING_FROZEN)
3799 			goto err_dead_proc_or_thread;
3800 	}
3801 	if (target_thread)
3802 		binder_thread_dec_tmpref(target_thread);
3803 	binder_proc_dec_tmpref(target_proc);
3804 	if (target_node)
3805 		binder_dec_node_tmpref(target_node);
3806 	/*
3807 	 * write barrier to synchronize with initialization
3808 	 * of log entry
3809 	 */
3810 	smp_wmb();
3811 	WRITE_ONCE(e->debug_id_done, t_debug_id);
3812 	return;
3813 
3814 err_dead_proc_or_thread:
3815 	binder_txn_error("%d:%d dead process or thread\n",
3816 		thread->pid, proc->pid);
3817 	return_error_line = __LINE__;
3818 	binder_dequeue_work(proc, tcomplete);
3819 err_translate_failed:
3820 err_bad_object_type:
3821 err_bad_offset:
3822 err_bad_parent:
3823 err_copy_data_failed:
3824 	binder_cleanup_deferred_txn_lists(&sgc_head, &pf_head);
3825 	binder_free_txn_fixups(t);
3826 	trace_binder_transaction_failed_buffer_release(t->buffer);
3827 	binder_transaction_buffer_release(target_proc, NULL, t->buffer,
3828 					  buffer_offset, true);
3829 	if (target_node)
3830 		binder_dec_node_tmpref(target_node);
3831 	target_node = NULL;
3832 	t->buffer->transaction = NULL;
3833 	binder_alloc_free_buf(&target_proc->alloc, t->buffer);
3834 err_binder_alloc_buf_failed:
3835 err_bad_extra_size:
3836 	if (lsmctx.context)
3837 		security_release_secctx(&lsmctx);
3838 err_get_secctx_failed:
3839 	kfree(tcomplete);
3840 	binder_stats_deleted(BINDER_STAT_TRANSACTION_COMPLETE);
3841 err_alloc_tcomplete_failed:
3842 	if (trace_binder_txn_latency_free_enabled())
3843 		binder_txn_latency_free(t);
3844 err_bad_todo_list:
3845 err_bad_call_stack:
3846 err_empty_call_stack:
3847 err_dead_binder:
3848 err_invalid_target_handle:
3849 	if (target_node) {
3850 		binder_dec_node(target_node, 1, 0);
3851 		binder_dec_node_tmpref(target_node);
3852 	}
3853 
3854 	binder_netlink_report(proc, t, tr->data_size, return_error);
3855 	kfree(t);
3856 	binder_stats_deleted(BINDER_STAT_TRANSACTION);
3857 err_alloc_t_failed:
3858 
3859 	binder_debug(BINDER_DEBUG_FAILED_TRANSACTION,
3860 		     "%d:%d transaction %s to %d:%d failed %d/%d/%d, code %u size %lld-%lld line %d\n",
3861 		     proc->pid, thread->pid, reply ? "reply" :
3862 		     (tr->flags & TF_ONE_WAY ? "async" : "call"),
3863 		     target_proc ? target_proc->pid : 0,
3864 		     target_thread ? target_thread->pid : 0,
3865 		     t_debug_id, return_error, return_error_param,
3866 		     tr->code, (u64)tr->data_size, (u64)tr->offsets_size,
3867 		     return_error_line);
3868 
3869 	if (target_thread)
3870 		binder_thread_dec_tmpref(target_thread);
3871 	if (target_proc)
3872 		binder_proc_dec_tmpref(target_proc);
3873 
3874 	{
3875 		struct binder_transaction_log_entry *fe;
3876 
3877 		e->return_error = return_error;
3878 		e->return_error_param = return_error_param;
3879 		e->return_error_line = return_error_line;
3880 		fe = binder_transaction_log_add(&binder_transaction_log_failed);
3881 		*fe = *e;
3882 		/*
3883 		 * write barrier to synchronize with initialization
3884 		 * of log entry
3885 		 */
3886 		smp_wmb();
3887 		WRITE_ONCE(e->debug_id_done, t_debug_id);
3888 		WRITE_ONCE(fe->debug_id_done, t_debug_id);
3889 	}
3890 
3891 	BUG_ON(thread->return_error.cmd != BR_OK);
3892 	if (in_reply_to) {
3893 		binder_set_txn_from_error(in_reply_to, t_debug_id,
3894 				return_error, return_error_param);
3895 		thread->return_error.cmd = BR_TRANSACTION_COMPLETE;
3896 		binder_enqueue_thread_work(thread, &thread->return_error.work);
3897 		binder_send_failed_reply(in_reply_to, return_error);
3898 	} else {
3899 		binder_inner_proc_lock(proc);
3900 		binder_set_extended_error(&thread->ee, t_debug_id,
3901 				return_error, return_error_param);
3902 		binder_inner_proc_unlock(proc);
3903 		thread->return_error.cmd = return_error;
3904 		binder_enqueue_thread_work(thread, &thread->return_error.work);
3905 	}
3906 }
3907 
3908 static int
binder_request_freeze_notification(struct binder_proc * proc,struct binder_thread * thread,struct binder_handle_cookie * handle_cookie)3909 binder_request_freeze_notification(struct binder_proc *proc,
3910 				   struct binder_thread *thread,
3911 				   struct binder_handle_cookie *handle_cookie)
3912 {
3913 	struct binder_ref_freeze *freeze;
3914 	struct binder_ref *ref;
3915 
3916 	freeze = kzalloc(sizeof(*freeze), GFP_KERNEL);
3917 	if (!freeze)
3918 		return -ENOMEM;
3919 	binder_proc_lock(proc);
3920 	ref = binder_get_ref_olocked(proc, handle_cookie->handle, false);
3921 	if (!ref) {
3922 		binder_user_error("%d:%d BC_REQUEST_FREEZE_NOTIFICATION invalid ref %d\n",
3923 				  proc->pid, thread->pid, handle_cookie->handle);
3924 		binder_proc_unlock(proc);
3925 		kfree(freeze);
3926 		return -EINVAL;
3927 	}
3928 
3929 	binder_node_lock(ref->node);
3930 	if (ref->freeze) {
3931 		binder_user_error("%d:%d BC_REQUEST_FREEZE_NOTIFICATION already set\n",
3932 				  proc->pid, thread->pid);
3933 		binder_node_unlock(ref->node);
3934 		binder_proc_unlock(proc);
3935 		kfree(freeze);
3936 		return -EINVAL;
3937 	}
3938 
3939 	binder_stats_created(BINDER_STAT_FREEZE);
3940 	INIT_LIST_HEAD(&freeze->work.entry);
3941 	freeze->cookie = handle_cookie->cookie;
3942 	freeze->work.type = BINDER_WORK_FROZEN_BINDER;
3943 	ref->freeze = freeze;
3944 
3945 	if (ref->node->proc) {
3946 		binder_inner_proc_lock(ref->node->proc);
3947 		freeze->is_frozen = ref->node->proc->is_frozen;
3948 		binder_inner_proc_unlock(ref->node->proc);
3949 
3950 		binder_inner_proc_lock(proc);
3951 		binder_enqueue_work_ilocked(&freeze->work, &proc->todo);
3952 		binder_wakeup_proc_ilocked(proc);
3953 		binder_inner_proc_unlock(proc);
3954 	}
3955 
3956 	binder_node_unlock(ref->node);
3957 	binder_proc_unlock(proc);
3958 	return 0;
3959 }
3960 
3961 static int
binder_clear_freeze_notification(struct binder_proc * proc,struct binder_thread * thread,struct binder_handle_cookie * handle_cookie)3962 binder_clear_freeze_notification(struct binder_proc *proc,
3963 				 struct binder_thread *thread,
3964 				 struct binder_handle_cookie *handle_cookie)
3965 {
3966 	struct binder_ref_freeze *freeze;
3967 	struct binder_ref *ref;
3968 
3969 	binder_proc_lock(proc);
3970 	ref = binder_get_ref_olocked(proc, handle_cookie->handle, false);
3971 	if (!ref) {
3972 		binder_user_error("%d:%d BC_CLEAR_FREEZE_NOTIFICATION invalid ref %d\n",
3973 				  proc->pid, thread->pid, handle_cookie->handle);
3974 		binder_proc_unlock(proc);
3975 		return -EINVAL;
3976 	}
3977 
3978 	binder_node_lock(ref->node);
3979 
3980 	if (!ref->freeze) {
3981 		binder_user_error("%d:%d BC_CLEAR_FREEZE_NOTIFICATION freeze notification not active\n",
3982 				  proc->pid, thread->pid);
3983 		binder_node_unlock(ref->node);
3984 		binder_proc_unlock(proc);
3985 		return -EINVAL;
3986 	}
3987 	freeze = ref->freeze;
3988 	binder_inner_proc_lock(proc);
3989 	if (freeze->cookie != handle_cookie->cookie) {
3990 		binder_user_error("%d:%d BC_CLEAR_FREEZE_NOTIFICATION freeze notification cookie mismatch %016llx != %016llx\n",
3991 				  proc->pid, thread->pid, (u64)freeze->cookie,
3992 				  (u64)handle_cookie->cookie);
3993 		binder_inner_proc_unlock(proc);
3994 		binder_node_unlock(ref->node);
3995 		binder_proc_unlock(proc);
3996 		return -EINVAL;
3997 	}
3998 	ref->freeze = NULL;
3999 	/*
4000 	 * Take the existing freeze object and overwrite its work type. There are three cases here:
4001 	 * 1. No pending notification. In this case just add the work to the queue.
4002 	 * 2. A notification was sent and is pending an ack from userspace. Once an ack arrives, we
4003 	 *    should resend with the new work type.
4004 	 * 3. A notification is pending to be sent. Since the work is already in the queue, nothing
4005 	 *    needs to be done here.
4006 	 */
4007 	freeze->work.type = BINDER_WORK_CLEAR_FREEZE_NOTIFICATION;
4008 	if (list_empty(&freeze->work.entry)) {
4009 		binder_enqueue_work_ilocked(&freeze->work, &proc->todo);
4010 		binder_wakeup_proc_ilocked(proc);
4011 	} else if (freeze->sent) {
4012 		freeze->resend = true;
4013 	}
4014 	binder_inner_proc_unlock(proc);
4015 	binder_node_unlock(ref->node);
4016 	binder_proc_unlock(proc);
4017 	return 0;
4018 }
4019 
4020 static int
binder_freeze_notification_done(struct binder_proc * proc,struct binder_thread * thread,binder_uintptr_t cookie)4021 binder_freeze_notification_done(struct binder_proc *proc,
4022 				struct binder_thread *thread,
4023 				binder_uintptr_t cookie)
4024 {
4025 	struct binder_ref_freeze *freeze = NULL;
4026 	struct binder_work *w;
4027 
4028 	binder_inner_proc_lock(proc);
4029 	list_for_each_entry(w, &proc->delivered_freeze, entry) {
4030 		struct binder_ref_freeze *tmp_freeze =
4031 			container_of(w, struct binder_ref_freeze, work);
4032 
4033 		if (tmp_freeze->cookie == cookie) {
4034 			freeze = tmp_freeze;
4035 			break;
4036 		}
4037 	}
4038 	if (!freeze) {
4039 		binder_user_error("%d:%d BC_FREEZE_NOTIFICATION_DONE %016llx not found\n",
4040 				  proc->pid, thread->pid, (u64)cookie);
4041 		binder_inner_proc_unlock(proc);
4042 		return -EINVAL;
4043 	}
4044 	binder_dequeue_work_ilocked(&freeze->work);
4045 	freeze->sent = false;
4046 	if (freeze->resend) {
4047 		freeze->resend = false;
4048 		binder_enqueue_work_ilocked(&freeze->work, &proc->todo);
4049 		binder_wakeup_proc_ilocked(proc);
4050 	}
4051 	binder_inner_proc_unlock(proc);
4052 	return 0;
4053 }
4054 
4055 /**
4056  * binder_free_buf() - free the specified buffer
4057  * @proc:       binder proc that owns buffer
4058  * @thread:     binder thread performing the buffer release
4059  * @buffer:     buffer to be freed
4060  * @is_failure: failed to send transaction
4061  *
4062  * If the buffer is for an async transaction, enqueue the next async
4063  * transaction from the node.
4064  *
4065  * Cleanup the buffer and free it.
4066  */
4067 static void
binder_free_buf(struct binder_proc * proc,struct binder_thread * thread,struct binder_buffer * buffer,bool is_failure)4068 binder_free_buf(struct binder_proc *proc,
4069 		struct binder_thread *thread,
4070 		struct binder_buffer *buffer, bool is_failure)
4071 {
4072 	binder_inner_proc_lock(proc);
4073 	if (buffer->transaction) {
4074 		buffer->transaction->buffer = NULL;
4075 		buffer->transaction = NULL;
4076 	}
4077 	binder_inner_proc_unlock(proc);
4078 	if (buffer->async_transaction && buffer->target_node) {
4079 		struct binder_node *buf_node;
4080 		struct binder_work *w;
4081 
4082 		buf_node = buffer->target_node;
4083 		binder_node_inner_lock(buf_node);
4084 		BUG_ON(!buf_node->has_async_transaction);
4085 		BUG_ON(buf_node->proc != proc);
4086 		w = binder_dequeue_work_head_ilocked(
4087 				&buf_node->async_todo);
4088 		if (!w) {
4089 			buf_node->has_async_transaction = false;
4090 		} else {
4091 			binder_enqueue_work_ilocked(
4092 					w, &proc->todo);
4093 			binder_wakeup_proc_ilocked(proc);
4094 		}
4095 		binder_node_inner_unlock(buf_node);
4096 	}
4097 	trace_binder_transaction_buffer_release(buffer);
4098 	binder_release_entire_buffer(proc, thread, buffer, is_failure);
4099 	binder_alloc_free_buf(&proc->alloc, buffer);
4100 }
4101 
binder_thread_write(struct binder_proc * proc,struct binder_thread * thread,binder_uintptr_t binder_buffer,size_t size,binder_size_t * consumed)4102 static int binder_thread_write(struct binder_proc *proc,
4103 			struct binder_thread *thread,
4104 			binder_uintptr_t binder_buffer, size_t size,
4105 			binder_size_t *consumed)
4106 {
4107 	uint32_t cmd;
4108 	struct binder_context *context = proc->context;
4109 	void __user *buffer = (void __user *)(uintptr_t)binder_buffer;
4110 	void __user *ptr = buffer + *consumed;
4111 	void __user *end = buffer + size;
4112 
4113 	while (ptr < end && thread->return_error.cmd == BR_OK) {
4114 		int ret;
4115 
4116 		if (get_user(cmd, (uint32_t __user *)ptr))
4117 			return -EFAULT;
4118 		ptr += sizeof(uint32_t);
4119 		trace_binder_command(cmd);
4120 		if (_IOC_NR(cmd) < ARRAY_SIZE(binder_stats.bc)) {
4121 			atomic_inc(&binder_stats.bc[_IOC_NR(cmd)]);
4122 			atomic_inc(&proc->stats.bc[_IOC_NR(cmd)]);
4123 			atomic_inc(&thread->stats.bc[_IOC_NR(cmd)]);
4124 		}
4125 		switch (cmd) {
4126 		case BC_INCREFS:
4127 		case BC_ACQUIRE:
4128 		case BC_RELEASE:
4129 		case BC_DECREFS: {
4130 			uint32_t target;
4131 			const char *debug_string;
4132 			bool strong = cmd == BC_ACQUIRE || cmd == BC_RELEASE;
4133 			bool increment = cmd == BC_INCREFS || cmd == BC_ACQUIRE;
4134 			struct binder_ref_data rdata;
4135 
4136 			if (get_user(target, (uint32_t __user *)ptr))
4137 				return -EFAULT;
4138 
4139 			ptr += sizeof(uint32_t);
4140 			ret = -1;
4141 			if (increment && !target) {
4142 				struct binder_node *ctx_mgr_node;
4143 
4144 				mutex_lock(&context->context_mgr_node_lock);
4145 				ctx_mgr_node = context->binder_context_mgr_node;
4146 				if (ctx_mgr_node) {
4147 					if (ctx_mgr_node->proc == proc) {
4148 						binder_user_error("%d:%d context manager tried to acquire desc 0\n",
4149 								  proc->pid, thread->pid);
4150 						mutex_unlock(&context->context_mgr_node_lock);
4151 						return -EINVAL;
4152 					}
4153 					ret = binder_inc_ref_for_node(
4154 							proc, ctx_mgr_node,
4155 							strong, NULL, &rdata);
4156 				}
4157 				mutex_unlock(&context->context_mgr_node_lock);
4158 			}
4159 			if (ret)
4160 				ret = binder_update_ref_for_handle(
4161 						proc, target, increment, strong,
4162 						&rdata);
4163 			if (!ret && rdata.desc != target) {
4164 				binder_user_error("%d:%d tried to acquire reference to desc %d, got %d instead\n",
4165 					proc->pid, thread->pid,
4166 					target, rdata.desc);
4167 			}
4168 			switch (cmd) {
4169 			case BC_INCREFS:
4170 				debug_string = "IncRefs";
4171 				break;
4172 			case BC_ACQUIRE:
4173 				debug_string = "Acquire";
4174 				break;
4175 			case BC_RELEASE:
4176 				debug_string = "Release";
4177 				break;
4178 			case BC_DECREFS:
4179 			default:
4180 				debug_string = "DecRefs";
4181 				break;
4182 			}
4183 			if (ret) {
4184 				binder_user_error("%d:%d %s %d refcount change on invalid ref %d ret %d\n",
4185 					proc->pid, thread->pid, debug_string,
4186 					strong, target, ret);
4187 				break;
4188 			}
4189 			binder_debug(BINDER_DEBUG_USER_REFS,
4190 				     "%d:%d %s ref %d desc %d s %d w %d\n",
4191 				     proc->pid, thread->pid, debug_string,
4192 				     rdata.debug_id, rdata.desc, rdata.strong,
4193 				     rdata.weak);
4194 			break;
4195 		}
4196 		case BC_INCREFS_DONE:
4197 		case BC_ACQUIRE_DONE: {
4198 			binder_uintptr_t node_ptr;
4199 			binder_uintptr_t cookie;
4200 			struct binder_node *node;
4201 			bool free_node;
4202 
4203 			if (get_user(node_ptr, (binder_uintptr_t __user *)ptr))
4204 				return -EFAULT;
4205 			ptr += sizeof(binder_uintptr_t);
4206 			if (get_user(cookie, (binder_uintptr_t __user *)ptr))
4207 				return -EFAULT;
4208 			ptr += sizeof(binder_uintptr_t);
4209 			node = binder_get_node(proc, node_ptr);
4210 			if (node == NULL) {
4211 				binder_user_error("%d:%d %s u%016llx no match\n",
4212 					proc->pid, thread->pid,
4213 					cmd == BC_INCREFS_DONE ?
4214 					"BC_INCREFS_DONE" :
4215 					"BC_ACQUIRE_DONE",
4216 					(u64)node_ptr);
4217 				break;
4218 			}
4219 			if (cookie != node->cookie) {
4220 				binder_user_error("%d:%d %s u%016llx node %d cookie mismatch %016llx != %016llx\n",
4221 					proc->pid, thread->pid,
4222 					cmd == BC_INCREFS_DONE ?
4223 					"BC_INCREFS_DONE" : "BC_ACQUIRE_DONE",
4224 					(u64)node_ptr, node->debug_id,
4225 					(u64)cookie, (u64)node->cookie);
4226 				binder_put_node(node);
4227 				break;
4228 			}
4229 			binder_node_inner_lock(node);
4230 			if (cmd == BC_ACQUIRE_DONE) {
4231 				if (node->pending_strong_ref == 0) {
4232 					binder_user_error("%d:%d BC_ACQUIRE_DONE node %d has no pending acquire request\n",
4233 						proc->pid, thread->pid,
4234 						node->debug_id);
4235 					binder_node_inner_unlock(node);
4236 					binder_put_node(node);
4237 					break;
4238 				}
4239 				node->pending_strong_ref = 0;
4240 			} else {
4241 				if (node->pending_weak_ref == 0) {
4242 					binder_user_error("%d:%d BC_INCREFS_DONE node %d has no pending increfs request\n",
4243 						proc->pid, thread->pid,
4244 						node->debug_id);
4245 					binder_node_inner_unlock(node);
4246 					binder_put_node(node);
4247 					break;
4248 				}
4249 				node->pending_weak_ref = 0;
4250 			}
4251 			free_node = binder_dec_node_nilocked(node,
4252 					cmd == BC_ACQUIRE_DONE, 0);
4253 			WARN_ON(free_node);
4254 			binder_debug(BINDER_DEBUG_USER_REFS,
4255 				     "%d:%d %s node %d ls %d lw %d tr %d\n",
4256 				     proc->pid, thread->pid,
4257 				     cmd == BC_INCREFS_DONE ? "BC_INCREFS_DONE" : "BC_ACQUIRE_DONE",
4258 				     node->debug_id, node->local_strong_refs,
4259 				     node->local_weak_refs, node->tmp_refs);
4260 			binder_node_inner_unlock(node);
4261 			binder_put_node(node);
4262 			break;
4263 		}
4264 		case BC_ATTEMPT_ACQUIRE:
4265 			pr_err("BC_ATTEMPT_ACQUIRE not supported\n");
4266 			return -EINVAL;
4267 		case BC_ACQUIRE_RESULT:
4268 			pr_err("BC_ACQUIRE_RESULT not supported\n");
4269 			return -EINVAL;
4270 
4271 		case BC_FREE_BUFFER: {
4272 			binder_uintptr_t data_ptr;
4273 			struct binder_buffer *buffer;
4274 
4275 			if (get_user(data_ptr, (binder_uintptr_t __user *)ptr))
4276 				return -EFAULT;
4277 			ptr += sizeof(binder_uintptr_t);
4278 
4279 			buffer = binder_alloc_prepare_to_free(&proc->alloc,
4280 							      data_ptr);
4281 			if (IS_ERR_OR_NULL(buffer)) {
4282 				if (PTR_ERR(buffer) == -EPERM) {
4283 					binder_user_error(
4284 						"%d:%d BC_FREE_BUFFER matched unreturned or currently freeing buffer at offset %lx\n",
4285 						proc->pid, thread->pid,
4286 						(unsigned long)data_ptr - proc->alloc.vm_start);
4287 				} else {
4288 					binder_user_error(
4289 						"%d:%d BC_FREE_BUFFER no match for buffer at offset %lx\n",
4290 						proc->pid, thread->pid,
4291 						(unsigned long)data_ptr - proc->alloc.vm_start);
4292 				}
4293 				break;
4294 			}
4295 			binder_debug(BINDER_DEBUG_FREE_BUFFER,
4296 				     "%d:%d BC_FREE_BUFFER at offset %lx found buffer %d for %s transaction\n",
4297 				     proc->pid, thread->pid,
4298 				     (unsigned long)data_ptr - proc->alloc.vm_start,
4299 				     buffer->debug_id,
4300 				     buffer->transaction ? "active" : "finished");
4301 			binder_free_buf(proc, thread, buffer, false);
4302 			break;
4303 		}
4304 
4305 		case BC_TRANSACTION_SG:
4306 		case BC_REPLY_SG: {
4307 			struct binder_transaction_data_sg tr;
4308 
4309 			if (copy_from_user(&tr, ptr, sizeof(tr)))
4310 				return -EFAULT;
4311 			ptr += sizeof(tr);
4312 			binder_transaction(proc, thread, &tr.transaction_data,
4313 					   cmd == BC_REPLY_SG, tr.buffers_size);
4314 			break;
4315 		}
4316 		case BC_TRANSACTION:
4317 		case BC_REPLY: {
4318 			struct binder_transaction_data tr;
4319 
4320 			if (copy_from_user(&tr, ptr, sizeof(tr)))
4321 				return -EFAULT;
4322 			ptr += sizeof(tr);
4323 			binder_transaction(proc, thread, &tr,
4324 					   cmd == BC_REPLY, 0);
4325 			break;
4326 		}
4327 
4328 		case BC_REGISTER_LOOPER:
4329 			binder_debug(BINDER_DEBUG_THREADS,
4330 				     "%d:%d BC_REGISTER_LOOPER\n",
4331 				     proc->pid, thread->pid);
4332 			binder_inner_proc_lock(proc);
4333 			if (thread->looper & BINDER_LOOPER_STATE_ENTERED) {
4334 				thread->looper |= BINDER_LOOPER_STATE_INVALID;
4335 				binder_user_error("%d:%d ERROR: BC_REGISTER_LOOPER called after BC_ENTER_LOOPER\n",
4336 					proc->pid, thread->pid);
4337 			} else if (proc->requested_threads == 0) {
4338 				thread->looper |= BINDER_LOOPER_STATE_INVALID;
4339 				binder_user_error("%d:%d ERROR: BC_REGISTER_LOOPER called without request\n",
4340 					proc->pid, thread->pid);
4341 			} else {
4342 				proc->requested_threads--;
4343 				proc->requested_threads_started++;
4344 			}
4345 			thread->looper |= BINDER_LOOPER_STATE_REGISTERED;
4346 			binder_inner_proc_unlock(proc);
4347 			break;
4348 		case BC_ENTER_LOOPER:
4349 			binder_debug(BINDER_DEBUG_THREADS,
4350 				     "%d:%d BC_ENTER_LOOPER\n",
4351 				     proc->pid, thread->pid);
4352 			if (thread->looper & BINDER_LOOPER_STATE_REGISTERED) {
4353 				thread->looper |= BINDER_LOOPER_STATE_INVALID;
4354 				binder_user_error("%d:%d ERROR: BC_ENTER_LOOPER called after BC_REGISTER_LOOPER\n",
4355 					proc->pid, thread->pid);
4356 			}
4357 			thread->looper |= BINDER_LOOPER_STATE_ENTERED;
4358 			break;
4359 		case BC_EXIT_LOOPER:
4360 			binder_debug(BINDER_DEBUG_THREADS,
4361 				     "%d:%d BC_EXIT_LOOPER\n",
4362 				     proc->pid, thread->pid);
4363 			thread->looper |= BINDER_LOOPER_STATE_EXITED;
4364 			break;
4365 
4366 		case BC_REQUEST_DEATH_NOTIFICATION:
4367 		case BC_CLEAR_DEATH_NOTIFICATION: {
4368 			uint32_t target;
4369 			binder_uintptr_t cookie;
4370 			struct binder_ref *ref;
4371 			struct binder_ref_death *death = NULL;
4372 
4373 			if (get_user(target, (uint32_t __user *)ptr))
4374 				return -EFAULT;
4375 			ptr += sizeof(uint32_t);
4376 			if (get_user(cookie, (binder_uintptr_t __user *)ptr))
4377 				return -EFAULT;
4378 			ptr += sizeof(binder_uintptr_t);
4379 			if (cmd == BC_REQUEST_DEATH_NOTIFICATION) {
4380 				/*
4381 				 * Allocate memory for death notification
4382 				 * before taking lock
4383 				 */
4384 				death = kzalloc(sizeof(*death), GFP_KERNEL);
4385 				if (death == NULL) {
4386 					WARN_ON(thread->return_error.cmd !=
4387 						BR_OK);
4388 					thread->return_error.cmd = BR_ERROR;
4389 					binder_enqueue_thread_work(
4390 						thread,
4391 						&thread->return_error.work);
4392 					binder_debug(
4393 						BINDER_DEBUG_FAILED_TRANSACTION,
4394 						"%d:%d BC_REQUEST_DEATH_NOTIFICATION failed\n",
4395 						proc->pid, thread->pid);
4396 					break;
4397 				}
4398 			}
4399 			binder_proc_lock(proc);
4400 			ref = binder_get_ref_olocked(proc, target, false);
4401 			if (ref == NULL) {
4402 				binder_user_error("%d:%d %s invalid ref %d\n",
4403 					proc->pid, thread->pid,
4404 					cmd == BC_REQUEST_DEATH_NOTIFICATION ?
4405 					"BC_REQUEST_DEATH_NOTIFICATION" :
4406 					"BC_CLEAR_DEATH_NOTIFICATION",
4407 					target);
4408 				binder_proc_unlock(proc);
4409 				kfree(death);
4410 				break;
4411 			}
4412 
4413 			binder_debug(BINDER_DEBUG_DEATH_NOTIFICATION,
4414 				     "%d:%d %s %016llx ref %d desc %d s %d w %d for node %d\n",
4415 				     proc->pid, thread->pid,
4416 				     cmd == BC_REQUEST_DEATH_NOTIFICATION ?
4417 				     "BC_REQUEST_DEATH_NOTIFICATION" :
4418 				     "BC_CLEAR_DEATH_NOTIFICATION",
4419 				     (u64)cookie, ref->data.debug_id,
4420 				     ref->data.desc, ref->data.strong,
4421 				     ref->data.weak, ref->node->debug_id);
4422 
4423 			binder_node_lock(ref->node);
4424 			if (cmd == BC_REQUEST_DEATH_NOTIFICATION) {
4425 				if (ref->death) {
4426 					binder_user_error("%d:%d BC_REQUEST_DEATH_NOTIFICATION death notification already set\n",
4427 						proc->pid, thread->pid);
4428 					binder_node_unlock(ref->node);
4429 					binder_proc_unlock(proc);
4430 					kfree(death);
4431 					break;
4432 				}
4433 				binder_stats_created(BINDER_STAT_DEATH);
4434 				INIT_LIST_HEAD(&death->work.entry);
4435 				death->cookie = cookie;
4436 				ref->death = death;
4437 				if (ref->node->proc == NULL) {
4438 					ref->death->work.type = BINDER_WORK_DEAD_BINDER;
4439 
4440 					binder_inner_proc_lock(proc);
4441 					binder_enqueue_work_ilocked(
4442 						&ref->death->work, &proc->todo);
4443 					binder_wakeup_proc_ilocked(proc);
4444 					binder_inner_proc_unlock(proc);
4445 				}
4446 			} else {
4447 				if (ref->death == NULL) {
4448 					binder_user_error("%d:%d BC_CLEAR_DEATH_NOTIFICATION death notification not active\n",
4449 						proc->pid, thread->pid);
4450 					binder_node_unlock(ref->node);
4451 					binder_proc_unlock(proc);
4452 					break;
4453 				}
4454 				death = ref->death;
4455 				if (death->cookie != cookie) {
4456 					binder_user_error("%d:%d BC_CLEAR_DEATH_NOTIFICATION death notification cookie mismatch %016llx != %016llx\n",
4457 						proc->pid, thread->pid,
4458 						(u64)death->cookie,
4459 						(u64)cookie);
4460 					binder_node_unlock(ref->node);
4461 					binder_proc_unlock(proc);
4462 					break;
4463 				}
4464 				ref->death = NULL;
4465 				binder_inner_proc_lock(proc);
4466 				if (list_empty(&death->work.entry)) {
4467 					death->work.type = BINDER_WORK_CLEAR_DEATH_NOTIFICATION;
4468 					if (thread->looper &
4469 					    (BINDER_LOOPER_STATE_REGISTERED |
4470 					     BINDER_LOOPER_STATE_ENTERED))
4471 						binder_enqueue_thread_work_ilocked(
4472 								thread,
4473 								&death->work);
4474 					else {
4475 						binder_enqueue_work_ilocked(
4476 								&death->work,
4477 								&proc->todo);
4478 						binder_wakeup_proc_ilocked(
4479 								proc);
4480 					}
4481 				} else {
4482 					BUG_ON(death->work.type != BINDER_WORK_DEAD_BINDER);
4483 					death->work.type = BINDER_WORK_DEAD_BINDER_AND_CLEAR;
4484 				}
4485 				binder_inner_proc_unlock(proc);
4486 			}
4487 			binder_node_unlock(ref->node);
4488 			binder_proc_unlock(proc);
4489 		} break;
4490 		case BC_DEAD_BINDER_DONE: {
4491 			struct binder_work *w;
4492 			binder_uintptr_t cookie;
4493 			struct binder_ref_death *death = NULL;
4494 
4495 			if (get_user(cookie, (binder_uintptr_t __user *)ptr))
4496 				return -EFAULT;
4497 
4498 			ptr += sizeof(cookie);
4499 			binder_inner_proc_lock(proc);
4500 			list_for_each_entry(w, &proc->delivered_death,
4501 					    entry) {
4502 				struct binder_ref_death *tmp_death =
4503 					container_of(w,
4504 						     struct binder_ref_death,
4505 						     work);
4506 
4507 				if (tmp_death->cookie == cookie) {
4508 					death = tmp_death;
4509 					break;
4510 				}
4511 			}
4512 			binder_debug(BINDER_DEBUG_DEAD_BINDER,
4513 				     "%d:%d BC_DEAD_BINDER_DONE %016llx found %pK\n",
4514 				     proc->pid, thread->pid, (u64)cookie,
4515 				     death);
4516 			if (death == NULL) {
4517 				binder_user_error("%d:%d BC_DEAD_BINDER_DONE %016llx not found\n",
4518 					proc->pid, thread->pid, (u64)cookie);
4519 				binder_inner_proc_unlock(proc);
4520 				break;
4521 			}
4522 			binder_dequeue_work_ilocked(&death->work);
4523 			if (death->work.type == BINDER_WORK_DEAD_BINDER_AND_CLEAR) {
4524 				death->work.type = BINDER_WORK_CLEAR_DEATH_NOTIFICATION;
4525 				if (thread->looper &
4526 					(BINDER_LOOPER_STATE_REGISTERED |
4527 					 BINDER_LOOPER_STATE_ENTERED))
4528 					binder_enqueue_thread_work_ilocked(
4529 						thread, &death->work);
4530 				else {
4531 					binder_enqueue_work_ilocked(
4532 							&death->work,
4533 							&proc->todo);
4534 					binder_wakeup_proc_ilocked(proc);
4535 				}
4536 			}
4537 			binder_inner_proc_unlock(proc);
4538 		} break;
4539 
4540 		case BC_REQUEST_FREEZE_NOTIFICATION: {
4541 			struct binder_handle_cookie handle_cookie;
4542 			int error;
4543 
4544 			if (copy_from_user(&handle_cookie, ptr, sizeof(handle_cookie)))
4545 				return -EFAULT;
4546 			ptr += sizeof(handle_cookie);
4547 			error = binder_request_freeze_notification(proc, thread,
4548 								   &handle_cookie);
4549 			if (error)
4550 				return error;
4551 		} break;
4552 
4553 		case BC_CLEAR_FREEZE_NOTIFICATION: {
4554 			struct binder_handle_cookie handle_cookie;
4555 			int error;
4556 
4557 			if (copy_from_user(&handle_cookie, ptr, sizeof(handle_cookie)))
4558 				return -EFAULT;
4559 			ptr += sizeof(handle_cookie);
4560 			error = binder_clear_freeze_notification(proc, thread, &handle_cookie);
4561 			if (error)
4562 				return error;
4563 		} break;
4564 
4565 		case BC_FREEZE_NOTIFICATION_DONE: {
4566 			binder_uintptr_t cookie;
4567 			int error;
4568 
4569 			if (get_user(cookie, (binder_uintptr_t __user *)ptr))
4570 				return -EFAULT;
4571 
4572 			ptr += sizeof(cookie);
4573 			error = binder_freeze_notification_done(proc, thread, cookie);
4574 			if (error)
4575 				return error;
4576 		} break;
4577 
4578 		default:
4579 			pr_err("%d:%d unknown command %u\n",
4580 			       proc->pid, thread->pid, cmd);
4581 			return -EINVAL;
4582 		}
4583 		*consumed = ptr - buffer;
4584 	}
4585 	return 0;
4586 }
4587 
binder_stat_br(struct binder_proc * proc,struct binder_thread * thread,uint32_t cmd)4588 static void binder_stat_br(struct binder_proc *proc,
4589 			   struct binder_thread *thread, uint32_t cmd)
4590 {
4591 	trace_binder_return(cmd);
4592 	if (_IOC_NR(cmd) < ARRAY_SIZE(binder_stats.br)) {
4593 		atomic_inc(&binder_stats.br[_IOC_NR(cmd)]);
4594 		atomic_inc(&proc->stats.br[_IOC_NR(cmd)]);
4595 		atomic_inc(&thread->stats.br[_IOC_NR(cmd)]);
4596 	}
4597 }
4598 
binder_put_node_cmd(struct binder_proc * proc,struct binder_thread * thread,void __user ** ptrp,binder_uintptr_t node_ptr,binder_uintptr_t node_cookie,int node_debug_id,uint32_t cmd,const char * cmd_name)4599 static int binder_put_node_cmd(struct binder_proc *proc,
4600 			       struct binder_thread *thread,
4601 			       void __user **ptrp,
4602 			       binder_uintptr_t node_ptr,
4603 			       binder_uintptr_t node_cookie,
4604 			       int node_debug_id,
4605 			       uint32_t cmd, const char *cmd_name)
4606 {
4607 	void __user *ptr = *ptrp;
4608 
4609 	if (put_user(cmd, (uint32_t __user *)ptr))
4610 		return -EFAULT;
4611 	ptr += sizeof(uint32_t);
4612 
4613 	if (put_user(node_ptr, (binder_uintptr_t __user *)ptr))
4614 		return -EFAULT;
4615 	ptr += sizeof(binder_uintptr_t);
4616 
4617 	if (put_user(node_cookie, (binder_uintptr_t __user *)ptr))
4618 		return -EFAULT;
4619 	ptr += sizeof(binder_uintptr_t);
4620 
4621 	binder_stat_br(proc, thread, cmd);
4622 	binder_debug(BINDER_DEBUG_USER_REFS, "%d:%d %s %d u%016llx c%016llx\n",
4623 		     proc->pid, thread->pid, cmd_name, node_debug_id,
4624 		     (u64)node_ptr, (u64)node_cookie);
4625 
4626 	*ptrp = ptr;
4627 	return 0;
4628 }
4629 
binder_wait_for_work(struct binder_thread * thread,bool do_proc_work)4630 static int binder_wait_for_work(struct binder_thread *thread,
4631 				bool do_proc_work)
4632 {
4633 	DEFINE_WAIT(wait);
4634 	struct binder_proc *proc = thread->proc;
4635 	int ret = 0;
4636 
4637 	binder_inner_proc_lock(proc);
4638 	for (;;) {
4639 		prepare_to_wait(&thread->wait, &wait, TASK_INTERRUPTIBLE|TASK_FREEZABLE);
4640 		if (binder_has_work_ilocked(thread, do_proc_work))
4641 			break;
4642 		if (do_proc_work)
4643 			list_add(&thread->waiting_thread_node,
4644 				 &proc->waiting_threads);
4645 		binder_inner_proc_unlock(proc);
4646 		schedule();
4647 		binder_inner_proc_lock(proc);
4648 		list_del_init(&thread->waiting_thread_node);
4649 		if (signal_pending(current)) {
4650 			ret = -EINTR;
4651 			break;
4652 		}
4653 	}
4654 	finish_wait(&thread->wait, &wait);
4655 	binder_inner_proc_unlock(proc);
4656 
4657 	return ret;
4658 }
4659 
4660 /**
4661  * binder_apply_fd_fixups() - finish fd translation
4662  * @proc:         binder_proc associated @t->buffer
4663  * @t:	binder transaction with list of fd fixups
4664  *
4665  * Now that we are in the context of the transaction target
4666  * process, we can allocate and install fds. Process the
4667  * list of fds to translate and fixup the buffer with the
4668  * new fds first and only then install the files.
4669  *
4670  * If we fail to allocate an fd, skip the install and release
4671  * any fds that have already been allocated.
4672  */
binder_apply_fd_fixups(struct binder_proc * proc,struct binder_transaction * t)4673 static int binder_apply_fd_fixups(struct binder_proc *proc,
4674 				  struct binder_transaction *t)
4675 {
4676 	struct binder_txn_fd_fixup *fixup, *tmp;
4677 	int ret = 0;
4678 
4679 	list_for_each_entry(fixup, &t->fd_fixups, fixup_entry) {
4680 		int fd = get_unused_fd_flags(O_CLOEXEC);
4681 
4682 		if (fd < 0) {
4683 			binder_debug(BINDER_DEBUG_TRANSACTION,
4684 				     "failed fd fixup txn %d fd %d\n",
4685 				     t->debug_id, fd);
4686 			ret = -ENOMEM;
4687 			goto err;
4688 		}
4689 		binder_debug(BINDER_DEBUG_TRANSACTION,
4690 			     "fd fixup txn %d fd %d\n",
4691 			     t->debug_id, fd);
4692 		trace_binder_transaction_fd_recv(t, fd, fixup->offset);
4693 		fixup->target_fd = fd;
4694 		if (binder_alloc_copy_to_buffer(&proc->alloc, t->buffer,
4695 						fixup->offset, &fd,
4696 						sizeof(u32))) {
4697 			ret = -EINVAL;
4698 			goto err;
4699 		}
4700 	}
4701 	list_for_each_entry_safe(fixup, tmp, &t->fd_fixups, fixup_entry) {
4702 		fd_install(fixup->target_fd, fixup->file);
4703 		list_del(&fixup->fixup_entry);
4704 		kfree(fixup);
4705 	}
4706 
4707 	return ret;
4708 
4709 err:
4710 	binder_free_txn_fixups(t);
4711 	return ret;
4712 }
4713 
binder_thread_read(struct binder_proc * proc,struct binder_thread * thread,binder_uintptr_t binder_buffer,size_t size,binder_size_t * consumed,int non_block)4714 static int binder_thread_read(struct binder_proc *proc,
4715 			      struct binder_thread *thread,
4716 			      binder_uintptr_t binder_buffer, size_t size,
4717 			      binder_size_t *consumed, int non_block)
4718 {
4719 	void __user *buffer = (void __user *)(uintptr_t)binder_buffer;
4720 	void __user *ptr = buffer + *consumed;
4721 	void __user *end = buffer + size;
4722 
4723 	int ret = 0;
4724 	int wait_for_proc_work;
4725 
4726 	if (*consumed == 0) {
4727 		if (put_user(BR_NOOP, (uint32_t __user *)ptr))
4728 			return -EFAULT;
4729 		ptr += sizeof(uint32_t);
4730 	}
4731 
4732 retry:
4733 	binder_inner_proc_lock(proc);
4734 	wait_for_proc_work = binder_available_for_proc_work_ilocked(thread);
4735 	binder_inner_proc_unlock(proc);
4736 
4737 	thread->looper |= BINDER_LOOPER_STATE_WAITING;
4738 
4739 	trace_binder_wait_for_work(wait_for_proc_work,
4740 				   !!thread->transaction_stack,
4741 				   !binder_worklist_empty(proc, &thread->todo));
4742 	if (wait_for_proc_work) {
4743 		if (!(thread->looper & (BINDER_LOOPER_STATE_REGISTERED |
4744 					BINDER_LOOPER_STATE_ENTERED))) {
4745 			binder_user_error("%d:%d ERROR: Thread waiting for process work before calling BC_REGISTER_LOOPER or BC_ENTER_LOOPER (state %x)\n",
4746 				proc->pid, thread->pid, thread->looper);
4747 			wait_event_interruptible(binder_user_error_wait,
4748 						 binder_stop_on_user_error < 2);
4749 		}
4750 		binder_set_nice(proc->default_priority);
4751 	}
4752 
4753 	if (non_block) {
4754 		if (!binder_has_work(thread, wait_for_proc_work))
4755 			ret = -EAGAIN;
4756 	} else {
4757 		ret = binder_wait_for_work(thread, wait_for_proc_work);
4758 	}
4759 
4760 	thread->looper &= ~BINDER_LOOPER_STATE_WAITING;
4761 
4762 	if (ret)
4763 		return ret;
4764 
4765 	while (1) {
4766 		uint32_t cmd;
4767 		struct binder_transaction_data_secctx tr;
4768 		struct binder_transaction_data *trd = &tr.transaction_data;
4769 		struct binder_work *w = NULL;
4770 		struct list_head *list = NULL;
4771 		struct binder_transaction *t = NULL;
4772 		struct binder_thread *t_from;
4773 		size_t trsize = sizeof(*trd);
4774 
4775 		binder_inner_proc_lock(proc);
4776 		if (!binder_worklist_empty_ilocked(&thread->todo))
4777 			list = &thread->todo;
4778 		else if (!binder_worklist_empty_ilocked(&proc->todo) &&
4779 			   wait_for_proc_work)
4780 			list = &proc->todo;
4781 		else {
4782 			binder_inner_proc_unlock(proc);
4783 
4784 			/* no data added */
4785 			if (ptr - buffer == 4 && !thread->looper_need_return)
4786 				goto retry;
4787 			break;
4788 		}
4789 
4790 		if (end - ptr < sizeof(tr) + 4) {
4791 			binder_inner_proc_unlock(proc);
4792 			break;
4793 		}
4794 		w = binder_dequeue_work_head_ilocked(list);
4795 		if (binder_worklist_empty_ilocked(&thread->todo))
4796 			thread->process_todo = false;
4797 
4798 		switch (w->type) {
4799 		case BINDER_WORK_TRANSACTION: {
4800 			binder_inner_proc_unlock(proc);
4801 			t = container_of(w, struct binder_transaction, work);
4802 		} break;
4803 		case BINDER_WORK_RETURN_ERROR: {
4804 			struct binder_error *e = container_of(
4805 					w, struct binder_error, work);
4806 
4807 			WARN_ON(e->cmd == BR_OK);
4808 			binder_inner_proc_unlock(proc);
4809 			if (put_user(e->cmd, (uint32_t __user *)ptr))
4810 				return -EFAULT;
4811 			cmd = e->cmd;
4812 			e->cmd = BR_OK;
4813 			ptr += sizeof(uint32_t);
4814 
4815 			binder_stat_br(proc, thread, cmd);
4816 		} break;
4817 		case BINDER_WORK_TRANSACTION_COMPLETE:
4818 		case BINDER_WORK_TRANSACTION_PENDING:
4819 		case BINDER_WORK_TRANSACTION_ONEWAY_SPAM_SUSPECT: {
4820 			if (proc->oneway_spam_detection_enabled &&
4821 				   w->type == BINDER_WORK_TRANSACTION_ONEWAY_SPAM_SUSPECT)
4822 				cmd = BR_ONEWAY_SPAM_SUSPECT;
4823 			else if (w->type == BINDER_WORK_TRANSACTION_PENDING)
4824 				cmd = BR_TRANSACTION_PENDING_FROZEN;
4825 			else
4826 				cmd = BR_TRANSACTION_COMPLETE;
4827 			binder_inner_proc_unlock(proc);
4828 			kfree(w);
4829 			binder_stats_deleted(BINDER_STAT_TRANSACTION_COMPLETE);
4830 			if (put_user(cmd, (uint32_t __user *)ptr))
4831 				return -EFAULT;
4832 			ptr += sizeof(uint32_t);
4833 
4834 			binder_stat_br(proc, thread, cmd);
4835 			binder_debug(BINDER_DEBUG_TRANSACTION_COMPLETE,
4836 				     "%d:%d BR_TRANSACTION_COMPLETE\n",
4837 				     proc->pid, thread->pid);
4838 		} break;
4839 		case BINDER_WORK_NODE: {
4840 			struct binder_node *node = container_of(w, struct binder_node, work);
4841 			int strong, weak;
4842 			binder_uintptr_t node_ptr = node->ptr;
4843 			binder_uintptr_t node_cookie = node->cookie;
4844 			int node_debug_id = node->debug_id;
4845 			int has_weak_ref;
4846 			int has_strong_ref;
4847 			void __user *orig_ptr = ptr;
4848 
4849 			BUG_ON(proc != node->proc);
4850 			strong = node->internal_strong_refs ||
4851 					node->local_strong_refs;
4852 			weak = !hlist_empty(&node->refs) ||
4853 					node->local_weak_refs ||
4854 					node->tmp_refs || strong;
4855 			has_strong_ref = node->has_strong_ref;
4856 			has_weak_ref = node->has_weak_ref;
4857 
4858 			if (weak && !has_weak_ref) {
4859 				node->has_weak_ref = 1;
4860 				node->pending_weak_ref = 1;
4861 				node->local_weak_refs++;
4862 			}
4863 			if (strong && !has_strong_ref) {
4864 				node->has_strong_ref = 1;
4865 				node->pending_strong_ref = 1;
4866 				node->local_strong_refs++;
4867 			}
4868 			if (!strong && has_strong_ref)
4869 				node->has_strong_ref = 0;
4870 			if (!weak && has_weak_ref)
4871 				node->has_weak_ref = 0;
4872 			if (!weak && !strong) {
4873 				binder_debug(BINDER_DEBUG_INTERNAL_REFS,
4874 					     "%d:%d node %d u%016llx c%016llx deleted\n",
4875 					     proc->pid, thread->pid,
4876 					     node_debug_id,
4877 					     (u64)node_ptr,
4878 					     (u64)node_cookie);
4879 				rb_erase(&node->rb_node, &proc->nodes);
4880 				binder_inner_proc_unlock(proc);
4881 				binder_node_lock(node);
4882 				/*
4883 				 * Acquire the node lock before freeing the
4884 				 * node to serialize with other threads that
4885 				 * may have been holding the node lock while
4886 				 * decrementing this node (avoids race where
4887 				 * this thread frees while the other thread
4888 				 * is unlocking the node after the final
4889 				 * decrement)
4890 				 */
4891 				binder_node_unlock(node);
4892 				binder_free_node(node);
4893 			} else
4894 				binder_inner_proc_unlock(proc);
4895 
4896 			if (weak && !has_weak_ref)
4897 				ret = binder_put_node_cmd(
4898 						proc, thread, &ptr, node_ptr,
4899 						node_cookie, node_debug_id,
4900 						BR_INCREFS, "BR_INCREFS");
4901 			if (!ret && strong && !has_strong_ref)
4902 				ret = binder_put_node_cmd(
4903 						proc, thread, &ptr, node_ptr,
4904 						node_cookie, node_debug_id,
4905 						BR_ACQUIRE, "BR_ACQUIRE");
4906 			if (!ret && !strong && has_strong_ref)
4907 				ret = binder_put_node_cmd(
4908 						proc, thread, &ptr, node_ptr,
4909 						node_cookie, node_debug_id,
4910 						BR_RELEASE, "BR_RELEASE");
4911 			if (!ret && !weak && has_weak_ref)
4912 				ret = binder_put_node_cmd(
4913 						proc, thread, &ptr, node_ptr,
4914 						node_cookie, node_debug_id,
4915 						BR_DECREFS, "BR_DECREFS");
4916 			if (orig_ptr == ptr)
4917 				binder_debug(BINDER_DEBUG_INTERNAL_REFS,
4918 					     "%d:%d node %d u%016llx c%016llx state unchanged\n",
4919 					     proc->pid, thread->pid,
4920 					     node_debug_id,
4921 					     (u64)node_ptr,
4922 					     (u64)node_cookie);
4923 			if (ret)
4924 				return ret;
4925 		} break;
4926 		case BINDER_WORK_DEAD_BINDER:
4927 		case BINDER_WORK_DEAD_BINDER_AND_CLEAR:
4928 		case BINDER_WORK_CLEAR_DEATH_NOTIFICATION: {
4929 			struct binder_ref_death *death;
4930 			uint32_t cmd;
4931 			binder_uintptr_t cookie;
4932 
4933 			death = container_of(w, struct binder_ref_death, work);
4934 			if (w->type == BINDER_WORK_CLEAR_DEATH_NOTIFICATION)
4935 				cmd = BR_CLEAR_DEATH_NOTIFICATION_DONE;
4936 			else
4937 				cmd = BR_DEAD_BINDER;
4938 			cookie = death->cookie;
4939 
4940 			binder_debug(BINDER_DEBUG_DEATH_NOTIFICATION,
4941 				     "%d:%d %s %016llx\n",
4942 				      proc->pid, thread->pid,
4943 				      cmd == BR_DEAD_BINDER ?
4944 				      "BR_DEAD_BINDER" :
4945 				      "BR_CLEAR_DEATH_NOTIFICATION_DONE",
4946 				      (u64)cookie);
4947 			if (w->type == BINDER_WORK_CLEAR_DEATH_NOTIFICATION) {
4948 				binder_inner_proc_unlock(proc);
4949 				kfree(death);
4950 				binder_stats_deleted(BINDER_STAT_DEATH);
4951 			} else {
4952 				binder_enqueue_work_ilocked(
4953 						w, &proc->delivered_death);
4954 				binder_inner_proc_unlock(proc);
4955 			}
4956 			if (put_user(cmd, (uint32_t __user *)ptr))
4957 				return -EFAULT;
4958 			ptr += sizeof(uint32_t);
4959 			if (put_user(cookie,
4960 				     (binder_uintptr_t __user *)ptr))
4961 				return -EFAULT;
4962 			ptr += sizeof(binder_uintptr_t);
4963 			binder_stat_br(proc, thread, cmd);
4964 			if (cmd == BR_DEAD_BINDER)
4965 				goto done; /* DEAD_BINDER notifications can cause transactions */
4966 		} break;
4967 
4968 		case BINDER_WORK_FROZEN_BINDER: {
4969 			struct binder_ref_freeze *freeze;
4970 			struct binder_frozen_state_info info;
4971 
4972 			memset(&info, 0, sizeof(info));
4973 			freeze = container_of(w, struct binder_ref_freeze, work);
4974 			info.is_frozen = freeze->is_frozen;
4975 			info.cookie = freeze->cookie;
4976 			freeze->sent = true;
4977 			binder_enqueue_work_ilocked(w, &proc->delivered_freeze);
4978 			binder_inner_proc_unlock(proc);
4979 
4980 			if (put_user(BR_FROZEN_BINDER, (uint32_t __user *)ptr))
4981 				return -EFAULT;
4982 			ptr += sizeof(uint32_t);
4983 			if (copy_to_user(ptr, &info, sizeof(info)))
4984 				return -EFAULT;
4985 			ptr += sizeof(info);
4986 			binder_stat_br(proc, thread, BR_FROZEN_BINDER);
4987 			goto done; /* BR_FROZEN_BINDER notifications can cause transactions */
4988 		} break;
4989 
4990 		case BINDER_WORK_CLEAR_FREEZE_NOTIFICATION: {
4991 			struct binder_ref_freeze *freeze =
4992 			    container_of(w, struct binder_ref_freeze, work);
4993 			binder_uintptr_t cookie = freeze->cookie;
4994 
4995 			binder_inner_proc_unlock(proc);
4996 			kfree(freeze);
4997 			binder_stats_deleted(BINDER_STAT_FREEZE);
4998 			if (put_user(BR_CLEAR_FREEZE_NOTIFICATION_DONE, (uint32_t __user *)ptr))
4999 				return -EFAULT;
5000 			ptr += sizeof(uint32_t);
5001 			if (put_user(cookie, (binder_uintptr_t __user *)ptr))
5002 				return -EFAULT;
5003 			ptr += sizeof(binder_uintptr_t);
5004 			binder_stat_br(proc, thread, BR_CLEAR_FREEZE_NOTIFICATION_DONE);
5005 		} break;
5006 
5007 		default:
5008 			binder_inner_proc_unlock(proc);
5009 			pr_err("%d:%d: bad work type %d\n",
5010 			       proc->pid, thread->pid, w->type);
5011 			break;
5012 		}
5013 
5014 		if (!t)
5015 			continue;
5016 
5017 		BUG_ON(t->buffer == NULL);
5018 		if (t->buffer->target_node) {
5019 			struct binder_node *target_node = t->buffer->target_node;
5020 
5021 			trd->target.ptr = target_node->ptr;
5022 			trd->cookie =  target_node->cookie;
5023 			t->saved_priority = task_nice(current);
5024 			if (t->priority < target_node->min_priority &&
5025 			    !(t->flags & TF_ONE_WAY))
5026 				binder_set_nice(t->priority);
5027 			else if (!(t->flags & TF_ONE_WAY) ||
5028 				 t->saved_priority > target_node->min_priority)
5029 				binder_set_nice(target_node->min_priority);
5030 			cmd = BR_TRANSACTION;
5031 		} else {
5032 			trd->target.ptr = 0;
5033 			trd->cookie = 0;
5034 			cmd = BR_REPLY;
5035 		}
5036 		trd->code = t->code;
5037 		trd->flags = t->flags;
5038 		trd->sender_euid = from_kuid(current_user_ns(), t->sender_euid);
5039 
5040 		t_from = binder_get_txn_from(t);
5041 		if (t_from) {
5042 			struct task_struct *sender = t_from->proc->tsk;
5043 
5044 			trd->sender_pid =
5045 				task_tgid_nr_ns(sender,
5046 						task_active_pid_ns(current));
5047 		} else {
5048 			trd->sender_pid = 0;
5049 		}
5050 
5051 		ret = binder_apply_fd_fixups(proc, t);
5052 		if (ret) {
5053 			struct binder_buffer *buffer = t->buffer;
5054 			bool oneway = !!(t->flags & TF_ONE_WAY);
5055 			int tid = t->debug_id;
5056 
5057 			if (t_from)
5058 				binder_thread_dec_tmpref(t_from);
5059 			buffer->transaction = NULL;
5060 			binder_cleanup_transaction(t, "fd fixups failed",
5061 						   BR_FAILED_REPLY);
5062 			binder_free_buf(proc, thread, buffer, true);
5063 			binder_debug(BINDER_DEBUG_FAILED_TRANSACTION,
5064 				     "%d:%d %stransaction %d fd fixups failed %d/%d, line %d\n",
5065 				     proc->pid, thread->pid,
5066 				     oneway ? "async " :
5067 					(cmd == BR_REPLY ? "reply " : ""),
5068 				     tid, BR_FAILED_REPLY, ret, __LINE__);
5069 			if (cmd == BR_REPLY) {
5070 				cmd = BR_FAILED_REPLY;
5071 				if (put_user(cmd, (uint32_t __user *)ptr))
5072 					return -EFAULT;
5073 				ptr += sizeof(uint32_t);
5074 				binder_stat_br(proc, thread, cmd);
5075 				break;
5076 			}
5077 			continue;
5078 		}
5079 		trd->data_size = t->buffer->data_size;
5080 		trd->offsets_size = t->buffer->offsets_size;
5081 		trd->data.ptr.buffer = t->buffer->user_data;
5082 		trd->data.ptr.offsets = trd->data.ptr.buffer +
5083 					ALIGN(t->buffer->data_size,
5084 					    sizeof(void *));
5085 
5086 		tr.secctx = t->security_ctx;
5087 		if (t->security_ctx) {
5088 			cmd = BR_TRANSACTION_SEC_CTX;
5089 			trsize = sizeof(tr);
5090 		}
5091 		if (put_user(cmd, (uint32_t __user *)ptr)) {
5092 			if (t_from)
5093 				binder_thread_dec_tmpref(t_from);
5094 
5095 			binder_cleanup_transaction(t, "put_user failed",
5096 						   BR_FAILED_REPLY);
5097 
5098 			return -EFAULT;
5099 		}
5100 		ptr += sizeof(uint32_t);
5101 		if (copy_to_user(ptr, &tr, trsize)) {
5102 			if (t_from)
5103 				binder_thread_dec_tmpref(t_from);
5104 
5105 			binder_cleanup_transaction(t, "copy_to_user failed",
5106 						   BR_FAILED_REPLY);
5107 
5108 			return -EFAULT;
5109 		}
5110 		ptr += trsize;
5111 
5112 		trace_binder_transaction_received(t);
5113 		binder_stat_br(proc, thread, cmd);
5114 		binder_debug(BINDER_DEBUG_TRANSACTION,
5115 			     "%d:%d %s %d %d:%d, cmd %u size %zd-%zd\n",
5116 			     proc->pid, thread->pid,
5117 			     (cmd == BR_TRANSACTION) ? "BR_TRANSACTION" :
5118 				(cmd == BR_TRANSACTION_SEC_CTX) ?
5119 				     "BR_TRANSACTION_SEC_CTX" : "BR_REPLY",
5120 			     t->debug_id, t_from ? t_from->proc->pid : 0,
5121 			     t_from ? t_from->pid : 0, cmd,
5122 			     t->buffer->data_size, t->buffer->offsets_size);
5123 
5124 		if (t_from)
5125 			binder_thread_dec_tmpref(t_from);
5126 		t->buffer->allow_user_free = 1;
5127 		if (cmd != BR_REPLY && !(t->flags & TF_ONE_WAY)) {
5128 			binder_inner_proc_lock(thread->proc);
5129 			t->to_parent = thread->transaction_stack;
5130 			t->to_thread = thread;
5131 			thread->transaction_stack = t;
5132 			binder_inner_proc_unlock(thread->proc);
5133 		} else {
5134 			binder_free_transaction(t);
5135 		}
5136 		break;
5137 	}
5138 
5139 done:
5140 
5141 	*consumed = ptr - buffer;
5142 	binder_inner_proc_lock(proc);
5143 	if (proc->requested_threads == 0 &&
5144 	    list_empty(&thread->proc->waiting_threads) &&
5145 	    proc->requested_threads_started < proc->max_threads &&
5146 	    (thread->looper & (BINDER_LOOPER_STATE_REGISTERED |
5147 	     BINDER_LOOPER_STATE_ENTERED)) /* the user-space code fails to */
5148 	     /*spawn a new thread if we leave this out */) {
5149 		proc->requested_threads++;
5150 		binder_inner_proc_unlock(proc);
5151 		binder_debug(BINDER_DEBUG_THREADS,
5152 			     "%d:%d BR_SPAWN_LOOPER\n",
5153 			     proc->pid, thread->pid);
5154 		if (put_user(BR_SPAWN_LOOPER, (uint32_t __user *)buffer))
5155 			return -EFAULT;
5156 		binder_stat_br(proc, thread, BR_SPAWN_LOOPER);
5157 	} else
5158 		binder_inner_proc_unlock(proc);
5159 	return 0;
5160 }
5161 
binder_release_work(struct binder_proc * proc,struct list_head * list)5162 static void binder_release_work(struct binder_proc *proc,
5163 				struct list_head *list)
5164 {
5165 	struct binder_work *w;
5166 	enum binder_work_type wtype;
5167 
5168 	while (1) {
5169 		binder_inner_proc_lock(proc);
5170 		w = binder_dequeue_work_head_ilocked(list);
5171 		wtype = w ? w->type : 0;
5172 		binder_inner_proc_unlock(proc);
5173 		if (!w)
5174 			return;
5175 
5176 		switch (wtype) {
5177 		case BINDER_WORK_TRANSACTION: {
5178 			struct binder_transaction *t;
5179 
5180 			t = container_of(w, struct binder_transaction, work);
5181 
5182 			binder_cleanup_transaction(t, "process died.",
5183 						   BR_DEAD_REPLY);
5184 		} break;
5185 		case BINDER_WORK_RETURN_ERROR: {
5186 			struct binder_error *e = container_of(
5187 					w, struct binder_error, work);
5188 
5189 			binder_debug(BINDER_DEBUG_DEAD_TRANSACTION,
5190 				"undelivered TRANSACTION_ERROR: %u\n",
5191 				e->cmd);
5192 		} break;
5193 		case BINDER_WORK_TRANSACTION_PENDING:
5194 		case BINDER_WORK_TRANSACTION_ONEWAY_SPAM_SUSPECT:
5195 		case BINDER_WORK_TRANSACTION_COMPLETE: {
5196 			binder_debug(BINDER_DEBUG_DEAD_TRANSACTION,
5197 				"undelivered TRANSACTION_COMPLETE\n");
5198 			kfree(w);
5199 			binder_stats_deleted(BINDER_STAT_TRANSACTION_COMPLETE);
5200 		} break;
5201 		case BINDER_WORK_DEAD_BINDER_AND_CLEAR:
5202 		case BINDER_WORK_CLEAR_DEATH_NOTIFICATION: {
5203 			struct binder_ref_death *death;
5204 
5205 			death = container_of(w, struct binder_ref_death, work);
5206 			binder_debug(BINDER_DEBUG_DEAD_TRANSACTION,
5207 				"undelivered death notification, %016llx\n",
5208 				(u64)death->cookie);
5209 			kfree(death);
5210 			binder_stats_deleted(BINDER_STAT_DEATH);
5211 		} break;
5212 		case BINDER_WORK_NODE:
5213 			break;
5214 		case BINDER_WORK_CLEAR_FREEZE_NOTIFICATION: {
5215 			struct binder_ref_freeze *freeze;
5216 
5217 			freeze = container_of(w, struct binder_ref_freeze, work);
5218 			binder_debug(BINDER_DEBUG_DEAD_TRANSACTION,
5219 				     "undelivered freeze notification, %016llx\n",
5220 				     (u64)freeze->cookie);
5221 			kfree(freeze);
5222 			binder_stats_deleted(BINDER_STAT_FREEZE);
5223 		} break;
5224 		default:
5225 			pr_err("unexpected work type, %d, not freed\n",
5226 			       wtype);
5227 			break;
5228 		}
5229 	}
5230 
5231 }
5232 
binder_get_thread_ilocked(struct binder_proc * proc,struct binder_thread * new_thread)5233 static struct binder_thread *binder_get_thread_ilocked(
5234 		struct binder_proc *proc, struct binder_thread *new_thread)
5235 {
5236 	struct binder_thread *thread = NULL;
5237 	struct rb_node *parent = NULL;
5238 	struct rb_node **p = &proc->threads.rb_node;
5239 
5240 	while (*p) {
5241 		parent = *p;
5242 		thread = rb_entry(parent, struct binder_thread, rb_node);
5243 
5244 		if (current->pid < thread->pid)
5245 			p = &(*p)->rb_left;
5246 		else if (current->pid > thread->pid)
5247 			p = &(*p)->rb_right;
5248 		else
5249 			return thread;
5250 	}
5251 	if (!new_thread)
5252 		return NULL;
5253 	thread = new_thread;
5254 	binder_stats_created(BINDER_STAT_THREAD);
5255 	thread->proc = proc;
5256 	thread->pid = current->pid;
5257 	atomic_set(&thread->tmp_ref, 0);
5258 	init_waitqueue_head(&thread->wait);
5259 	INIT_LIST_HEAD(&thread->todo);
5260 	rb_link_node(&thread->rb_node, parent, p);
5261 	rb_insert_color(&thread->rb_node, &proc->threads);
5262 	thread->looper_need_return = true;
5263 	thread->return_error.work.type = BINDER_WORK_RETURN_ERROR;
5264 	thread->return_error.cmd = BR_OK;
5265 	thread->reply_error.work.type = BINDER_WORK_RETURN_ERROR;
5266 	thread->reply_error.cmd = BR_OK;
5267 	thread->ee.command = BR_OK;
5268 	INIT_LIST_HEAD(&new_thread->waiting_thread_node);
5269 	return thread;
5270 }
5271 
binder_get_thread(struct binder_proc * proc)5272 static struct binder_thread *binder_get_thread(struct binder_proc *proc)
5273 {
5274 	struct binder_thread *thread;
5275 	struct binder_thread *new_thread;
5276 
5277 	binder_inner_proc_lock(proc);
5278 	thread = binder_get_thread_ilocked(proc, NULL);
5279 	binder_inner_proc_unlock(proc);
5280 	if (!thread) {
5281 		new_thread = kzalloc(sizeof(*thread), GFP_KERNEL);
5282 		if (new_thread == NULL)
5283 			return NULL;
5284 		binder_inner_proc_lock(proc);
5285 		thread = binder_get_thread_ilocked(proc, new_thread);
5286 		binder_inner_proc_unlock(proc);
5287 		if (thread != new_thread)
5288 			kfree(new_thread);
5289 	}
5290 	return thread;
5291 }
5292 
binder_free_proc(struct binder_proc * proc)5293 static void binder_free_proc(struct binder_proc *proc)
5294 {
5295 	struct binder_device *device;
5296 
5297 	BUG_ON(!list_empty(&proc->todo));
5298 	BUG_ON(!list_empty(&proc->delivered_death));
5299 	if (proc->outstanding_txns)
5300 		pr_warn("%s: Unexpected outstanding_txns %d\n",
5301 			__func__, proc->outstanding_txns);
5302 	device = container_of(proc->context, struct binder_device, context);
5303 	if (refcount_dec_and_test(&device->ref)) {
5304 		binder_remove_device(device);
5305 		kfree(proc->context->name);
5306 		kfree(device);
5307 	}
5308 	binder_alloc_deferred_release(&proc->alloc);
5309 	put_task_struct(proc->tsk);
5310 	put_cred(proc->cred);
5311 	binder_stats_deleted(BINDER_STAT_PROC);
5312 	dbitmap_free(&proc->dmap);
5313 	kfree(proc);
5314 }
5315 
binder_free_thread(struct binder_thread * thread)5316 static void binder_free_thread(struct binder_thread *thread)
5317 {
5318 	BUG_ON(!list_empty(&thread->todo));
5319 	binder_stats_deleted(BINDER_STAT_THREAD);
5320 	binder_proc_dec_tmpref(thread->proc);
5321 	kfree(thread);
5322 }
5323 
binder_thread_release(struct binder_proc * proc,struct binder_thread * thread)5324 static int binder_thread_release(struct binder_proc *proc,
5325 				 struct binder_thread *thread)
5326 {
5327 	struct binder_transaction *t;
5328 	struct binder_transaction *send_reply = NULL;
5329 	int active_transactions = 0;
5330 	struct binder_transaction *last_t = NULL;
5331 
5332 	binder_inner_proc_lock(thread->proc);
5333 	/*
5334 	 * take a ref on the proc so it survives
5335 	 * after we remove this thread from proc->threads.
5336 	 * The corresponding dec is when we actually
5337 	 * free the thread in binder_free_thread()
5338 	 */
5339 	proc->tmp_ref++;
5340 	/*
5341 	 * take a ref on this thread to ensure it
5342 	 * survives while we are releasing it
5343 	 */
5344 	atomic_inc(&thread->tmp_ref);
5345 	rb_erase(&thread->rb_node, &proc->threads);
5346 	t = thread->transaction_stack;
5347 	if (t) {
5348 		spin_lock(&t->lock);
5349 		if (t->to_thread == thread)
5350 			send_reply = t;
5351 	} else {
5352 		__acquire(&t->lock);
5353 	}
5354 	thread->is_dead = true;
5355 
5356 	while (t) {
5357 		last_t = t;
5358 		active_transactions++;
5359 		binder_debug(BINDER_DEBUG_DEAD_TRANSACTION,
5360 			     "release %d:%d transaction %d %s, still active\n",
5361 			      proc->pid, thread->pid,
5362 			     t->debug_id,
5363 			     (t->to_thread == thread) ? "in" : "out");
5364 
5365 		if (t->to_thread == thread) {
5366 			thread->proc->outstanding_txns--;
5367 			t->to_proc = NULL;
5368 			t->to_thread = NULL;
5369 			if (t->buffer) {
5370 				t->buffer->transaction = NULL;
5371 				t->buffer = NULL;
5372 			}
5373 			t = t->to_parent;
5374 		} else if (t->from == thread) {
5375 			t->from = NULL;
5376 			t = t->from_parent;
5377 		} else
5378 			BUG();
5379 		spin_unlock(&last_t->lock);
5380 		if (t)
5381 			spin_lock(&t->lock);
5382 		else
5383 			__acquire(&t->lock);
5384 	}
5385 	/* annotation for sparse, lock not acquired in last iteration above */
5386 	__release(&t->lock);
5387 
5388 	/*
5389 	 * If this thread used poll, make sure we remove the waitqueue from any
5390 	 * poll data structures holding it.
5391 	 */
5392 	if (thread->looper & BINDER_LOOPER_STATE_POLL)
5393 		wake_up_pollfree(&thread->wait);
5394 
5395 	binder_inner_proc_unlock(thread->proc);
5396 
5397 	/*
5398 	 * This is needed to avoid races between wake_up_pollfree() above and
5399 	 * someone else removing the last entry from the queue for other reasons
5400 	 * (e.g. ep_remove_wait_queue() being called due to an epoll file
5401 	 * descriptor being closed).  Such other users hold an RCU read lock, so
5402 	 * we can be sure they're done after we call synchronize_rcu().
5403 	 */
5404 	if (thread->looper & BINDER_LOOPER_STATE_POLL)
5405 		synchronize_rcu();
5406 
5407 	if (send_reply)
5408 		binder_send_failed_reply(send_reply, BR_DEAD_REPLY);
5409 	binder_release_work(proc, &thread->todo);
5410 	binder_thread_dec_tmpref(thread);
5411 	return active_transactions;
5412 }
5413 
binder_poll(struct file * filp,struct poll_table_struct * wait)5414 static __poll_t binder_poll(struct file *filp,
5415 				struct poll_table_struct *wait)
5416 {
5417 	struct binder_proc *proc = filp->private_data;
5418 	struct binder_thread *thread = NULL;
5419 	bool wait_for_proc_work;
5420 
5421 	thread = binder_get_thread(proc);
5422 	if (!thread)
5423 		return EPOLLERR;
5424 
5425 	binder_inner_proc_lock(thread->proc);
5426 	thread->looper |= BINDER_LOOPER_STATE_POLL;
5427 	wait_for_proc_work = binder_available_for_proc_work_ilocked(thread);
5428 
5429 	binder_inner_proc_unlock(thread->proc);
5430 
5431 	poll_wait(filp, &thread->wait, wait);
5432 
5433 	if (binder_has_work(thread, wait_for_proc_work))
5434 		return EPOLLIN;
5435 
5436 	return 0;
5437 }
5438 
binder_ioctl_write_read(struct file * filp,unsigned long arg,struct binder_thread * thread)5439 static int binder_ioctl_write_read(struct file *filp, unsigned long arg,
5440 				struct binder_thread *thread)
5441 {
5442 	int ret = 0;
5443 	struct binder_proc *proc = filp->private_data;
5444 	void __user *ubuf = (void __user *)arg;
5445 	struct binder_write_read bwr;
5446 
5447 	if (copy_from_user(&bwr, ubuf, sizeof(bwr)))
5448 		return -EFAULT;
5449 
5450 	binder_debug(BINDER_DEBUG_READ_WRITE,
5451 		     "%d:%d write %lld at %016llx, read %lld at %016llx\n",
5452 		     proc->pid, thread->pid,
5453 		     (u64)bwr.write_size, (u64)bwr.write_buffer,
5454 		     (u64)bwr.read_size, (u64)bwr.read_buffer);
5455 
5456 	if (bwr.write_size > 0) {
5457 		ret = binder_thread_write(proc, thread,
5458 					  bwr.write_buffer,
5459 					  bwr.write_size,
5460 					  &bwr.write_consumed);
5461 		trace_binder_write_done(ret);
5462 		if (ret < 0) {
5463 			bwr.read_consumed = 0;
5464 			goto out;
5465 		}
5466 	}
5467 	if (bwr.read_size > 0) {
5468 		ret = binder_thread_read(proc, thread, bwr.read_buffer,
5469 					 bwr.read_size,
5470 					 &bwr.read_consumed,
5471 					 filp->f_flags & O_NONBLOCK);
5472 		trace_binder_read_done(ret);
5473 		binder_inner_proc_lock(proc);
5474 		if (!binder_worklist_empty_ilocked(&proc->todo))
5475 			binder_wakeup_proc_ilocked(proc);
5476 		binder_inner_proc_unlock(proc);
5477 		if (ret < 0)
5478 			goto out;
5479 	}
5480 	binder_debug(BINDER_DEBUG_READ_WRITE,
5481 		     "%d:%d wrote %lld of %lld, read return %lld of %lld\n",
5482 		     proc->pid, thread->pid,
5483 		     (u64)bwr.write_consumed, (u64)bwr.write_size,
5484 		     (u64)bwr.read_consumed, (u64)bwr.read_size);
5485 out:
5486 	if (copy_to_user(ubuf, &bwr, sizeof(bwr)))
5487 		ret = -EFAULT;
5488 	return ret;
5489 }
5490 
binder_ioctl_set_ctx_mgr(struct file * filp,struct flat_binder_object * fbo)5491 static int binder_ioctl_set_ctx_mgr(struct file *filp,
5492 				    struct flat_binder_object *fbo)
5493 {
5494 	int ret = 0;
5495 	struct binder_proc *proc = filp->private_data;
5496 	struct binder_context *context = proc->context;
5497 	struct binder_node *new_node;
5498 	kuid_t curr_euid = current_euid();
5499 
5500 	guard(mutex)(&context->context_mgr_node_lock);
5501 	if (context->binder_context_mgr_node) {
5502 		pr_err("BINDER_SET_CONTEXT_MGR already set\n");
5503 		return -EBUSY;
5504 	}
5505 	ret = security_binder_set_context_mgr(proc->cred);
5506 	if (ret < 0)
5507 		return ret;
5508 	if (uid_valid(context->binder_context_mgr_uid)) {
5509 		if (!uid_eq(context->binder_context_mgr_uid, curr_euid)) {
5510 			pr_err("BINDER_SET_CONTEXT_MGR bad uid %d != %d\n",
5511 			       from_kuid(&init_user_ns, curr_euid),
5512 			       from_kuid(&init_user_ns,
5513 					 context->binder_context_mgr_uid));
5514 			return -EPERM;
5515 		}
5516 	} else {
5517 		context->binder_context_mgr_uid = curr_euid;
5518 	}
5519 	new_node = binder_new_node(proc, fbo);
5520 	if (!new_node)
5521 		return -ENOMEM;
5522 	binder_node_lock(new_node);
5523 	new_node->local_weak_refs++;
5524 	new_node->local_strong_refs++;
5525 	new_node->has_strong_ref = 1;
5526 	new_node->has_weak_ref = 1;
5527 	context->binder_context_mgr_node = new_node;
5528 	binder_node_unlock(new_node);
5529 	binder_put_node(new_node);
5530 	return ret;
5531 }
5532 
binder_ioctl_get_node_info_for_ref(struct binder_proc * proc,struct binder_node_info_for_ref * info)5533 static int binder_ioctl_get_node_info_for_ref(struct binder_proc *proc,
5534 		struct binder_node_info_for_ref *info)
5535 {
5536 	struct binder_node *node;
5537 	struct binder_context *context = proc->context;
5538 	__u32 handle = info->handle;
5539 
5540 	if (info->strong_count || info->weak_count || info->reserved1 ||
5541 	    info->reserved2 || info->reserved3) {
5542 		binder_user_error("%d BINDER_GET_NODE_INFO_FOR_REF: only handle may be non-zero.",
5543 				  proc->pid);
5544 		return -EINVAL;
5545 	}
5546 
5547 	/* This ioctl may only be used by the context manager */
5548 	mutex_lock(&context->context_mgr_node_lock);
5549 	if (!context->binder_context_mgr_node ||
5550 		context->binder_context_mgr_node->proc != proc) {
5551 		mutex_unlock(&context->context_mgr_node_lock);
5552 		return -EPERM;
5553 	}
5554 	mutex_unlock(&context->context_mgr_node_lock);
5555 
5556 	node = binder_get_node_from_ref(proc, handle, true, NULL);
5557 	if (!node)
5558 		return -EINVAL;
5559 
5560 	info->strong_count = node->local_strong_refs +
5561 		node->internal_strong_refs;
5562 	info->weak_count = node->local_weak_refs;
5563 
5564 	binder_put_node(node);
5565 
5566 	return 0;
5567 }
5568 
binder_ioctl_get_node_debug_info(struct binder_proc * proc,struct binder_node_debug_info * info)5569 static int binder_ioctl_get_node_debug_info(struct binder_proc *proc,
5570 				struct binder_node_debug_info *info)
5571 {
5572 	struct rb_node *n;
5573 	binder_uintptr_t ptr = info->ptr;
5574 
5575 	memset(info, 0, sizeof(*info));
5576 
5577 	binder_inner_proc_lock(proc);
5578 	for (n = rb_first(&proc->nodes); n != NULL; n = rb_next(n)) {
5579 		struct binder_node *node = rb_entry(n, struct binder_node,
5580 						    rb_node);
5581 		if (node->ptr > ptr) {
5582 			info->ptr = node->ptr;
5583 			info->cookie = node->cookie;
5584 			info->has_strong_ref = node->has_strong_ref;
5585 			info->has_weak_ref = node->has_weak_ref;
5586 			break;
5587 		}
5588 	}
5589 	binder_inner_proc_unlock(proc);
5590 
5591 	return 0;
5592 }
5593 
binder_txns_pending_ilocked(struct binder_proc * proc)5594 static bool binder_txns_pending_ilocked(struct binder_proc *proc)
5595 {
5596 	struct rb_node *n;
5597 	struct binder_thread *thread;
5598 
5599 	if (proc->outstanding_txns > 0)
5600 		return true;
5601 
5602 	for (n = rb_first(&proc->threads); n; n = rb_next(n)) {
5603 		thread = rb_entry(n, struct binder_thread, rb_node);
5604 		if (thread->transaction_stack)
5605 			return true;
5606 	}
5607 	return false;
5608 }
5609 
binder_add_freeze_work(struct binder_proc * proc,bool is_frozen)5610 static void binder_add_freeze_work(struct binder_proc *proc, bool is_frozen)
5611 {
5612 	struct binder_node *prev = NULL;
5613 	struct rb_node *n;
5614 	struct binder_ref *ref;
5615 
5616 	binder_inner_proc_lock(proc);
5617 	for (n = rb_first(&proc->nodes); n; n = rb_next(n)) {
5618 		struct binder_node *node;
5619 
5620 		node = rb_entry(n, struct binder_node, rb_node);
5621 		binder_inc_node_tmpref_ilocked(node);
5622 		binder_inner_proc_unlock(proc);
5623 		if (prev)
5624 			binder_put_node(prev);
5625 		binder_node_lock(node);
5626 		hlist_for_each_entry(ref, &node->refs, node_entry) {
5627 			/*
5628 			 * Need the node lock to synchronize
5629 			 * with new notification requests and the
5630 			 * inner lock to synchronize with queued
5631 			 * freeze notifications.
5632 			 */
5633 			binder_inner_proc_lock(ref->proc);
5634 			if (!ref->freeze) {
5635 				binder_inner_proc_unlock(ref->proc);
5636 				continue;
5637 			}
5638 			ref->freeze->work.type = BINDER_WORK_FROZEN_BINDER;
5639 			if (list_empty(&ref->freeze->work.entry)) {
5640 				ref->freeze->is_frozen = is_frozen;
5641 				binder_enqueue_work_ilocked(&ref->freeze->work, &ref->proc->todo);
5642 				binder_wakeup_proc_ilocked(ref->proc);
5643 			} else {
5644 				if (ref->freeze->sent && ref->freeze->is_frozen != is_frozen)
5645 					ref->freeze->resend = true;
5646 				ref->freeze->is_frozen = is_frozen;
5647 			}
5648 			binder_inner_proc_unlock(ref->proc);
5649 		}
5650 		prev = node;
5651 		binder_node_unlock(node);
5652 		binder_inner_proc_lock(proc);
5653 		if (proc->is_dead)
5654 			break;
5655 	}
5656 	binder_inner_proc_unlock(proc);
5657 	if (prev)
5658 		binder_put_node(prev);
5659 }
5660 
binder_ioctl_freeze(struct binder_freeze_info * info,struct binder_proc * target_proc)5661 static int binder_ioctl_freeze(struct binder_freeze_info *info,
5662 			       struct binder_proc *target_proc)
5663 {
5664 	int ret = 0;
5665 
5666 	if (!info->enable) {
5667 		binder_inner_proc_lock(target_proc);
5668 		target_proc->sync_recv = false;
5669 		target_proc->async_recv = false;
5670 		target_proc->is_frozen = false;
5671 		binder_inner_proc_unlock(target_proc);
5672 		binder_add_freeze_work(target_proc, false);
5673 		return 0;
5674 	}
5675 
5676 	/*
5677 	 * Freezing the target. Prevent new transactions by
5678 	 * setting frozen state. If timeout specified, wait
5679 	 * for transactions to drain.
5680 	 */
5681 	binder_inner_proc_lock(target_proc);
5682 	target_proc->sync_recv = false;
5683 	target_proc->async_recv = false;
5684 	target_proc->is_frozen = true;
5685 	binder_inner_proc_unlock(target_proc);
5686 
5687 	if (info->timeout_ms > 0)
5688 		ret = wait_event_interruptible_timeout(
5689 			target_proc->freeze_wait,
5690 			(!target_proc->outstanding_txns),
5691 			msecs_to_jiffies(info->timeout_ms));
5692 
5693 	/* Check pending transactions that wait for reply */
5694 	if (ret >= 0) {
5695 		binder_inner_proc_lock(target_proc);
5696 		if (binder_txns_pending_ilocked(target_proc))
5697 			ret = -EAGAIN;
5698 		binder_inner_proc_unlock(target_proc);
5699 	}
5700 
5701 	if (ret < 0) {
5702 		binder_inner_proc_lock(target_proc);
5703 		target_proc->is_frozen = false;
5704 		binder_inner_proc_unlock(target_proc);
5705 	} else {
5706 		binder_add_freeze_work(target_proc, true);
5707 	}
5708 
5709 	return ret;
5710 }
5711 
binder_ioctl_get_freezer_info(struct binder_frozen_status_info * info)5712 static int binder_ioctl_get_freezer_info(
5713 				struct binder_frozen_status_info *info)
5714 {
5715 	struct binder_proc *target_proc;
5716 	bool found = false;
5717 	__u32 txns_pending;
5718 
5719 	info->sync_recv = 0;
5720 	info->async_recv = 0;
5721 
5722 	mutex_lock(&binder_procs_lock);
5723 	hlist_for_each_entry(target_proc, &binder_procs, proc_node) {
5724 		if (target_proc->pid == info->pid) {
5725 			found = true;
5726 			binder_inner_proc_lock(target_proc);
5727 			txns_pending = binder_txns_pending_ilocked(target_proc);
5728 			info->sync_recv |= target_proc->sync_recv |
5729 					(txns_pending << 1);
5730 			info->async_recv |= target_proc->async_recv;
5731 			binder_inner_proc_unlock(target_proc);
5732 		}
5733 	}
5734 	mutex_unlock(&binder_procs_lock);
5735 
5736 	if (!found)
5737 		return -EINVAL;
5738 
5739 	return 0;
5740 }
5741 
binder_ioctl_get_extended_error(struct binder_thread * thread,void __user * ubuf)5742 static int binder_ioctl_get_extended_error(struct binder_thread *thread,
5743 					   void __user *ubuf)
5744 {
5745 	struct binder_extended_error ee;
5746 
5747 	binder_inner_proc_lock(thread->proc);
5748 	ee = thread->ee;
5749 	binder_set_extended_error(&thread->ee, 0, BR_OK, 0);
5750 	binder_inner_proc_unlock(thread->proc);
5751 
5752 	if (copy_to_user(ubuf, &ee, sizeof(ee)))
5753 		return -EFAULT;
5754 
5755 	return 0;
5756 }
5757 
binder_ioctl(struct file * filp,unsigned int cmd,unsigned long arg)5758 static long binder_ioctl(struct file *filp, unsigned int cmd, unsigned long arg)
5759 {
5760 	int ret;
5761 	struct binder_proc *proc = filp->private_data;
5762 	struct binder_thread *thread;
5763 	void __user *ubuf = (void __user *)arg;
5764 
5765 	trace_binder_ioctl(cmd, arg);
5766 
5767 	ret = wait_event_interruptible(binder_user_error_wait, binder_stop_on_user_error < 2);
5768 	if (ret)
5769 		goto err_unlocked;
5770 
5771 	thread = binder_get_thread(proc);
5772 	if (thread == NULL) {
5773 		ret = -ENOMEM;
5774 		goto err;
5775 	}
5776 
5777 	switch (cmd) {
5778 	case BINDER_WRITE_READ:
5779 		ret = binder_ioctl_write_read(filp, arg, thread);
5780 		if (ret)
5781 			goto err;
5782 		break;
5783 	case BINDER_SET_MAX_THREADS: {
5784 		u32 max_threads;
5785 
5786 		if (copy_from_user(&max_threads, ubuf,
5787 				   sizeof(max_threads))) {
5788 			ret = -EINVAL;
5789 			goto err;
5790 		}
5791 		binder_inner_proc_lock(proc);
5792 		proc->max_threads = max_threads;
5793 		binder_inner_proc_unlock(proc);
5794 		break;
5795 	}
5796 	case BINDER_SET_CONTEXT_MGR_EXT: {
5797 		struct flat_binder_object fbo;
5798 
5799 		if (copy_from_user(&fbo, ubuf, sizeof(fbo))) {
5800 			ret = -EINVAL;
5801 			goto err;
5802 		}
5803 		ret = binder_ioctl_set_ctx_mgr(filp, &fbo);
5804 		if (ret)
5805 			goto err;
5806 		break;
5807 	}
5808 	case BINDER_SET_CONTEXT_MGR:
5809 		ret = binder_ioctl_set_ctx_mgr(filp, NULL);
5810 		if (ret)
5811 			goto err;
5812 		break;
5813 	case BINDER_THREAD_EXIT:
5814 		binder_debug(BINDER_DEBUG_THREADS, "%d:%d exit\n",
5815 			     proc->pid, thread->pid);
5816 		binder_thread_release(proc, thread);
5817 		thread = NULL;
5818 		break;
5819 	case BINDER_VERSION: {
5820 		struct binder_version __user *ver = ubuf;
5821 
5822 		if (put_user(BINDER_CURRENT_PROTOCOL_VERSION,
5823 			     &ver->protocol_version)) {
5824 			ret = -EINVAL;
5825 			goto err;
5826 		}
5827 		break;
5828 	}
5829 	case BINDER_GET_NODE_INFO_FOR_REF: {
5830 		struct binder_node_info_for_ref info;
5831 
5832 		if (copy_from_user(&info, ubuf, sizeof(info))) {
5833 			ret = -EFAULT;
5834 			goto err;
5835 		}
5836 
5837 		ret = binder_ioctl_get_node_info_for_ref(proc, &info);
5838 		if (ret < 0)
5839 			goto err;
5840 
5841 		if (copy_to_user(ubuf, &info, sizeof(info))) {
5842 			ret = -EFAULT;
5843 			goto err;
5844 		}
5845 
5846 		break;
5847 	}
5848 	case BINDER_GET_NODE_DEBUG_INFO: {
5849 		struct binder_node_debug_info info;
5850 
5851 		if (copy_from_user(&info, ubuf, sizeof(info))) {
5852 			ret = -EFAULT;
5853 			goto err;
5854 		}
5855 
5856 		ret = binder_ioctl_get_node_debug_info(proc, &info);
5857 		if (ret < 0)
5858 			goto err;
5859 
5860 		if (copy_to_user(ubuf, &info, sizeof(info))) {
5861 			ret = -EFAULT;
5862 			goto err;
5863 		}
5864 		break;
5865 	}
5866 	case BINDER_FREEZE: {
5867 		struct binder_freeze_info info;
5868 		struct binder_proc **target_procs = NULL, *target_proc;
5869 		int target_procs_count = 0, i = 0;
5870 
5871 		ret = 0;
5872 
5873 		if (copy_from_user(&info, ubuf, sizeof(info))) {
5874 			ret = -EFAULT;
5875 			goto err;
5876 		}
5877 
5878 		mutex_lock(&binder_procs_lock);
5879 		hlist_for_each_entry(target_proc, &binder_procs, proc_node) {
5880 			if (target_proc->pid == info.pid)
5881 				target_procs_count++;
5882 		}
5883 
5884 		if (target_procs_count == 0) {
5885 			mutex_unlock(&binder_procs_lock);
5886 			ret = -EINVAL;
5887 			goto err;
5888 		}
5889 
5890 		target_procs = kcalloc(target_procs_count,
5891 				       sizeof(struct binder_proc *),
5892 				       GFP_KERNEL);
5893 
5894 		if (!target_procs) {
5895 			mutex_unlock(&binder_procs_lock);
5896 			ret = -ENOMEM;
5897 			goto err;
5898 		}
5899 
5900 		hlist_for_each_entry(target_proc, &binder_procs, proc_node) {
5901 			if (target_proc->pid != info.pid)
5902 				continue;
5903 
5904 			binder_inner_proc_lock(target_proc);
5905 			target_proc->tmp_ref++;
5906 			binder_inner_proc_unlock(target_proc);
5907 
5908 			target_procs[i++] = target_proc;
5909 		}
5910 		mutex_unlock(&binder_procs_lock);
5911 
5912 		for (i = 0; i < target_procs_count; i++) {
5913 			if (ret >= 0)
5914 				ret = binder_ioctl_freeze(&info,
5915 							  target_procs[i]);
5916 
5917 			binder_proc_dec_tmpref(target_procs[i]);
5918 		}
5919 
5920 		kfree(target_procs);
5921 
5922 		if (ret < 0)
5923 			goto err;
5924 		break;
5925 	}
5926 	case BINDER_GET_FROZEN_INFO: {
5927 		struct binder_frozen_status_info info;
5928 
5929 		if (copy_from_user(&info, ubuf, sizeof(info))) {
5930 			ret = -EFAULT;
5931 			goto err;
5932 		}
5933 
5934 		ret = binder_ioctl_get_freezer_info(&info);
5935 		if (ret < 0)
5936 			goto err;
5937 
5938 		if (copy_to_user(ubuf, &info, sizeof(info))) {
5939 			ret = -EFAULT;
5940 			goto err;
5941 		}
5942 		break;
5943 	}
5944 	case BINDER_ENABLE_ONEWAY_SPAM_DETECTION: {
5945 		uint32_t enable;
5946 
5947 		if (copy_from_user(&enable, ubuf, sizeof(enable))) {
5948 			ret = -EFAULT;
5949 			goto err;
5950 		}
5951 		binder_inner_proc_lock(proc);
5952 		proc->oneway_spam_detection_enabled = (bool)enable;
5953 		binder_inner_proc_unlock(proc);
5954 		break;
5955 	}
5956 	case BINDER_GET_EXTENDED_ERROR:
5957 		ret = binder_ioctl_get_extended_error(thread, ubuf);
5958 		if (ret < 0)
5959 			goto err;
5960 		break;
5961 	default:
5962 		ret = -EINVAL;
5963 		goto err;
5964 	}
5965 	ret = 0;
5966 err:
5967 	if (thread)
5968 		thread->looper_need_return = false;
5969 	wait_event_interruptible(binder_user_error_wait, binder_stop_on_user_error < 2);
5970 	if (ret && ret != -EINTR)
5971 		pr_info("%d:%d ioctl %x %lx returned %d\n", proc->pid, current->pid, cmd, arg, ret);
5972 err_unlocked:
5973 	trace_binder_ioctl_done(ret);
5974 	return ret;
5975 }
5976 
binder_vma_open(struct vm_area_struct * vma)5977 static void binder_vma_open(struct vm_area_struct *vma)
5978 {
5979 	struct binder_proc *proc = vma->vm_private_data;
5980 
5981 	binder_debug(BINDER_DEBUG_OPEN_CLOSE,
5982 		     "%d open vm area %lx-%lx (%ld K) vma %lx pagep %lx\n",
5983 		     proc->pid, vma->vm_start, vma->vm_end,
5984 		     (vma->vm_end - vma->vm_start) / SZ_1K, vma->vm_flags,
5985 		     (unsigned long)pgprot_val(vma->vm_page_prot));
5986 }
5987 
binder_vma_close(struct vm_area_struct * vma)5988 static void binder_vma_close(struct vm_area_struct *vma)
5989 {
5990 	struct binder_proc *proc = vma->vm_private_data;
5991 
5992 	binder_debug(BINDER_DEBUG_OPEN_CLOSE,
5993 		     "%d close vm area %lx-%lx (%ld K) vma %lx pagep %lx\n",
5994 		     proc->pid, vma->vm_start, vma->vm_end,
5995 		     (vma->vm_end - vma->vm_start) / SZ_1K, vma->vm_flags,
5996 		     (unsigned long)pgprot_val(vma->vm_page_prot));
5997 	binder_alloc_vma_close(&proc->alloc);
5998 }
5999 
binder_vm_fault(struct vm_fault * vmf)6000 VISIBLE_IF_KUNIT vm_fault_t binder_vm_fault(struct vm_fault *vmf)
6001 {
6002 	return VM_FAULT_SIGBUS;
6003 }
6004 EXPORT_SYMBOL_IF_KUNIT(binder_vm_fault);
6005 
6006 static const struct vm_operations_struct binder_vm_ops = {
6007 	.open = binder_vma_open,
6008 	.close = binder_vma_close,
6009 	.fault = binder_vm_fault,
6010 };
6011 
binder_mmap(struct file * filp,struct vm_area_struct * vma)6012 static int binder_mmap(struct file *filp, struct vm_area_struct *vma)
6013 {
6014 	struct binder_proc *proc = filp->private_data;
6015 
6016 	if (proc->tsk != current->group_leader)
6017 		return -EINVAL;
6018 
6019 	binder_debug(BINDER_DEBUG_OPEN_CLOSE,
6020 		     "%s: %d %lx-%lx (%ld K) vma %lx pagep %lx\n",
6021 		     __func__, proc->pid, vma->vm_start, vma->vm_end,
6022 		     (vma->vm_end - vma->vm_start) / SZ_1K, vma->vm_flags,
6023 		     (unsigned long)pgprot_val(vma->vm_page_prot));
6024 
6025 	if (vma->vm_flags & FORBIDDEN_MMAP_FLAGS) {
6026 		pr_err("%s: %d %lx-%lx %s failed %d\n", __func__,
6027 		       proc->pid, vma->vm_start, vma->vm_end, "bad vm_flags", -EPERM);
6028 		return -EPERM;
6029 	}
6030 	vm_flags_mod(vma, VM_DONTCOPY | VM_MIXEDMAP, VM_MAYWRITE);
6031 
6032 	vma->vm_ops = &binder_vm_ops;
6033 	vma->vm_private_data = proc;
6034 
6035 	return binder_alloc_mmap_handler(&proc->alloc, vma);
6036 }
6037 
binder_open(struct inode * nodp,struct file * filp)6038 static int binder_open(struct inode *nodp, struct file *filp)
6039 {
6040 	struct binder_proc *proc, *itr;
6041 	struct binder_device *binder_dev;
6042 	struct binderfs_info *info;
6043 	struct dentry *binder_binderfs_dir_entry_proc = NULL;
6044 	bool existing_pid = false;
6045 
6046 	binder_debug(BINDER_DEBUG_OPEN_CLOSE, "%s: %d:%d\n", __func__,
6047 		     current->group_leader->pid, current->pid);
6048 
6049 	proc = kzalloc(sizeof(*proc), GFP_KERNEL);
6050 	if (proc == NULL)
6051 		return -ENOMEM;
6052 
6053 	dbitmap_init(&proc->dmap);
6054 	spin_lock_init(&proc->inner_lock);
6055 	spin_lock_init(&proc->outer_lock);
6056 	get_task_struct(current->group_leader);
6057 	proc->tsk = current->group_leader;
6058 	proc->cred = get_cred(filp->f_cred);
6059 	INIT_LIST_HEAD(&proc->todo);
6060 	init_waitqueue_head(&proc->freeze_wait);
6061 	proc->default_priority = task_nice(current);
6062 	/* binderfs stashes devices in i_private */
6063 	if (is_binderfs_device(nodp)) {
6064 		binder_dev = nodp->i_private;
6065 		info = nodp->i_sb->s_fs_info;
6066 		binder_binderfs_dir_entry_proc = info->proc_log_dir;
6067 	} else {
6068 		binder_dev = container_of(filp->private_data,
6069 					  struct binder_device, miscdev);
6070 	}
6071 	refcount_inc(&binder_dev->ref);
6072 	proc->context = &binder_dev->context;
6073 	binder_alloc_init(&proc->alloc);
6074 
6075 	binder_stats_created(BINDER_STAT_PROC);
6076 	proc->pid = current->group_leader->pid;
6077 	INIT_LIST_HEAD(&proc->delivered_death);
6078 	INIT_LIST_HEAD(&proc->delivered_freeze);
6079 	INIT_LIST_HEAD(&proc->waiting_threads);
6080 	filp->private_data = proc;
6081 
6082 	mutex_lock(&binder_procs_lock);
6083 	hlist_for_each_entry(itr, &binder_procs, proc_node) {
6084 		if (itr->pid == proc->pid) {
6085 			existing_pid = true;
6086 			break;
6087 		}
6088 	}
6089 	hlist_add_head(&proc->proc_node, &binder_procs);
6090 	mutex_unlock(&binder_procs_lock);
6091 
6092 	if (binder_debugfs_dir_entry_proc && !existing_pid) {
6093 		char strbuf[11];
6094 
6095 		snprintf(strbuf, sizeof(strbuf), "%u", proc->pid);
6096 		/*
6097 		 * proc debug entries are shared between contexts.
6098 		 * Only create for the first PID to avoid debugfs log spamming
6099 		 * The printing code will anyway print all contexts for a given
6100 		 * PID so this is not a problem.
6101 		 */
6102 		proc->debugfs_entry = debugfs_create_file(strbuf, 0444,
6103 			binder_debugfs_dir_entry_proc,
6104 			(void *)(unsigned long)proc->pid,
6105 			&proc_fops);
6106 	}
6107 
6108 	if (binder_binderfs_dir_entry_proc && !existing_pid) {
6109 		char strbuf[11];
6110 		struct dentry *binderfs_entry;
6111 
6112 		snprintf(strbuf, sizeof(strbuf), "%u", proc->pid);
6113 		/*
6114 		 * Similar to debugfs, the process specific log file is shared
6115 		 * between contexts. Only create for the first PID.
6116 		 * This is ok since same as debugfs, the log file will contain
6117 		 * information on all contexts of a given PID.
6118 		 */
6119 		binderfs_entry = binderfs_create_file(binder_binderfs_dir_entry_proc,
6120 			strbuf, &proc_fops, (void *)(unsigned long)proc->pid);
6121 		if (!IS_ERR(binderfs_entry)) {
6122 			proc->binderfs_entry = binderfs_entry;
6123 		} else {
6124 			int error;
6125 
6126 			error = PTR_ERR(binderfs_entry);
6127 			pr_warn("Unable to create file %s in binderfs (error %d)\n",
6128 				strbuf, error);
6129 		}
6130 	}
6131 
6132 	return 0;
6133 }
6134 
binder_flush(struct file * filp,fl_owner_t id)6135 static int binder_flush(struct file *filp, fl_owner_t id)
6136 {
6137 	struct binder_proc *proc = filp->private_data;
6138 
6139 	binder_defer_work(proc, BINDER_DEFERRED_FLUSH);
6140 
6141 	return 0;
6142 }
6143 
binder_deferred_flush(struct binder_proc * proc)6144 static void binder_deferred_flush(struct binder_proc *proc)
6145 {
6146 	struct rb_node *n;
6147 	int wake_count = 0;
6148 
6149 	binder_inner_proc_lock(proc);
6150 	for (n = rb_first(&proc->threads); n != NULL; n = rb_next(n)) {
6151 		struct binder_thread *thread = rb_entry(n, struct binder_thread, rb_node);
6152 
6153 		thread->looper_need_return = true;
6154 		if (thread->looper & BINDER_LOOPER_STATE_WAITING) {
6155 			wake_up_interruptible(&thread->wait);
6156 			wake_count++;
6157 		}
6158 	}
6159 	binder_inner_proc_unlock(proc);
6160 
6161 	binder_debug(BINDER_DEBUG_OPEN_CLOSE,
6162 		     "binder_flush: %d woke %d threads\n", proc->pid,
6163 		     wake_count);
6164 }
6165 
binder_release(struct inode * nodp,struct file * filp)6166 static int binder_release(struct inode *nodp, struct file *filp)
6167 {
6168 	struct binder_proc *proc = filp->private_data;
6169 
6170 	debugfs_remove(proc->debugfs_entry);
6171 
6172 	if (proc->binderfs_entry) {
6173 		simple_recursive_removal(proc->binderfs_entry, NULL);
6174 		proc->binderfs_entry = NULL;
6175 	}
6176 
6177 	binder_defer_work(proc, BINDER_DEFERRED_RELEASE);
6178 
6179 	return 0;
6180 }
6181 
binder_node_release(struct binder_node * node,int refs)6182 static int binder_node_release(struct binder_node *node, int refs)
6183 {
6184 	struct binder_ref *ref;
6185 	int death = 0;
6186 	struct binder_proc *proc = node->proc;
6187 
6188 	binder_release_work(proc, &node->async_todo);
6189 
6190 	binder_node_lock(node);
6191 	binder_inner_proc_lock(proc);
6192 	binder_dequeue_work_ilocked(&node->work);
6193 	/*
6194 	 * The caller must have taken a temporary ref on the node,
6195 	 */
6196 	BUG_ON(!node->tmp_refs);
6197 	if (hlist_empty(&node->refs) && node->tmp_refs == 1) {
6198 		binder_inner_proc_unlock(proc);
6199 		binder_node_unlock(node);
6200 		binder_free_node(node);
6201 
6202 		return refs;
6203 	}
6204 
6205 	node->proc = NULL;
6206 	node->local_strong_refs = 0;
6207 	node->local_weak_refs = 0;
6208 	binder_inner_proc_unlock(proc);
6209 
6210 	spin_lock(&binder_dead_nodes_lock);
6211 	hlist_add_head(&node->dead_node, &binder_dead_nodes);
6212 	spin_unlock(&binder_dead_nodes_lock);
6213 
6214 	hlist_for_each_entry(ref, &node->refs, node_entry) {
6215 		refs++;
6216 		/*
6217 		 * Need the node lock to synchronize
6218 		 * with new notification requests and the
6219 		 * inner lock to synchronize with queued
6220 		 * death notifications.
6221 		 */
6222 		binder_inner_proc_lock(ref->proc);
6223 		if (!ref->death) {
6224 			binder_inner_proc_unlock(ref->proc);
6225 			continue;
6226 		}
6227 
6228 		death++;
6229 
6230 		BUG_ON(!list_empty(&ref->death->work.entry));
6231 		ref->death->work.type = BINDER_WORK_DEAD_BINDER;
6232 		binder_enqueue_work_ilocked(&ref->death->work,
6233 					    &ref->proc->todo);
6234 		binder_wakeup_proc_ilocked(ref->proc);
6235 		binder_inner_proc_unlock(ref->proc);
6236 	}
6237 
6238 	binder_debug(BINDER_DEBUG_DEAD_BINDER,
6239 		     "node %d now dead, refs %d, death %d\n",
6240 		     node->debug_id, refs, death);
6241 	binder_node_unlock(node);
6242 	binder_put_node(node);
6243 
6244 	return refs;
6245 }
6246 
binder_deferred_release(struct binder_proc * proc)6247 static void binder_deferred_release(struct binder_proc *proc)
6248 {
6249 	struct binder_context *context = proc->context;
6250 	struct rb_node *n;
6251 	int threads, nodes, incoming_refs, outgoing_refs, active_transactions;
6252 
6253 	mutex_lock(&binder_procs_lock);
6254 	hlist_del(&proc->proc_node);
6255 	mutex_unlock(&binder_procs_lock);
6256 
6257 	mutex_lock(&context->context_mgr_node_lock);
6258 	if (context->binder_context_mgr_node &&
6259 	    context->binder_context_mgr_node->proc == proc) {
6260 		binder_debug(BINDER_DEBUG_DEAD_BINDER,
6261 			     "%s: %d context_mgr_node gone\n",
6262 			     __func__, proc->pid);
6263 		context->binder_context_mgr_node = NULL;
6264 	}
6265 	mutex_unlock(&context->context_mgr_node_lock);
6266 	binder_inner_proc_lock(proc);
6267 	/*
6268 	 * Make sure proc stays alive after we
6269 	 * remove all the threads
6270 	 */
6271 	proc->tmp_ref++;
6272 
6273 	proc->is_dead = true;
6274 	proc->is_frozen = false;
6275 	proc->sync_recv = false;
6276 	proc->async_recv = false;
6277 	threads = 0;
6278 	active_transactions = 0;
6279 	while ((n = rb_first(&proc->threads))) {
6280 		struct binder_thread *thread;
6281 
6282 		thread = rb_entry(n, struct binder_thread, rb_node);
6283 		binder_inner_proc_unlock(proc);
6284 		threads++;
6285 		active_transactions += binder_thread_release(proc, thread);
6286 		binder_inner_proc_lock(proc);
6287 	}
6288 
6289 	nodes = 0;
6290 	incoming_refs = 0;
6291 	while ((n = rb_first(&proc->nodes))) {
6292 		struct binder_node *node;
6293 
6294 		node = rb_entry(n, struct binder_node, rb_node);
6295 		nodes++;
6296 		/*
6297 		 * take a temporary ref on the node before
6298 		 * calling binder_node_release() which will either
6299 		 * kfree() the node or call binder_put_node()
6300 		 */
6301 		binder_inc_node_tmpref_ilocked(node);
6302 		rb_erase(&node->rb_node, &proc->nodes);
6303 		binder_inner_proc_unlock(proc);
6304 		incoming_refs = binder_node_release(node, incoming_refs);
6305 		binder_inner_proc_lock(proc);
6306 	}
6307 	binder_inner_proc_unlock(proc);
6308 
6309 	outgoing_refs = 0;
6310 	binder_proc_lock(proc);
6311 	while ((n = rb_first(&proc->refs_by_desc))) {
6312 		struct binder_ref *ref;
6313 
6314 		ref = rb_entry(n, struct binder_ref, rb_node_desc);
6315 		outgoing_refs++;
6316 		binder_cleanup_ref_olocked(ref);
6317 		binder_proc_unlock(proc);
6318 		binder_free_ref(ref);
6319 		binder_proc_lock(proc);
6320 	}
6321 	binder_proc_unlock(proc);
6322 
6323 	binder_release_work(proc, &proc->todo);
6324 	binder_release_work(proc, &proc->delivered_death);
6325 	binder_release_work(proc, &proc->delivered_freeze);
6326 
6327 	binder_debug(BINDER_DEBUG_OPEN_CLOSE,
6328 		     "%s: %d threads %d, nodes %d (ref %d), refs %d, active transactions %d\n",
6329 		     __func__, proc->pid, threads, nodes, incoming_refs,
6330 		     outgoing_refs, active_transactions);
6331 
6332 	binder_proc_dec_tmpref(proc);
6333 }
6334 
binder_deferred_func(struct work_struct * work)6335 static void binder_deferred_func(struct work_struct *work)
6336 {
6337 	struct binder_proc *proc;
6338 
6339 	int defer;
6340 
6341 	do {
6342 		mutex_lock(&binder_deferred_lock);
6343 		if (!hlist_empty(&binder_deferred_list)) {
6344 			proc = hlist_entry(binder_deferred_list.first,
6345 					struct binder_proc, deferred_work_node);
6346 			hlist_del_init(&proc->deferred_work_node);
6347 			defer = proc->deferred_work;
6348 			proc->deferred_work = 0;
6349 		} else {
6350 			proc = NULL;
6351 			defer = 0;
6352 		}
6353 		mutex_unlock(&binder_deferred_lock);
6354 
6355 		if (defer & BINDER_DEFERRED_FLUSH)
6356 			binder_deferred_flush(proc);
6357 
6358 		if (defer & BINDER_DEFERRED_RELEASE)
6359 			binder_deferred_release(proc); /* frees proc */
6360 	} while (proc);
6361 }
6362 static DECLARE_WORK(binder_deferred_work, binder_deferred_func);
6363 
6364 static void
binder_defer_work(struct binder_proc * proc,enum binder_deferred_state defer)6365 binder_defer_work(struct binder_proc *proc, enum binder_deferred_state defer)
6366 {
6367 	guard(mutex)(&binder_deferred_lock);
6368 	proc->deferred_work |= defer;
6369 	if (hlist_unhashed(&proc->deferred_work_node)) {
6370 		hlist_add_head(&proc->deferred_work_node,
6371 				&binder_deferred_list);
6372 		schedule_work(&binder_deferred_work);
6373 	}
6374 }
6375 
print_binder_transaction_ilocked(struct seq_file * m,struct binder_proc * proc,const char * prefix,struct binder_transaction * t)6376 static void print_binder_transaction_ilocked(struct seq_file *m,
6377 					     struct binder_proc *proc,
6378 					     const char *prefix,
6379 					     struct binder_transaction *t)
6380 {
6381 	struct binder_proc *to_proc;
6382 	struct binder_buffer *buffer = t->buffer;
6383 	ktime_t current_time = ktime_get();
6384 
6385 	spin_lock(&t->lock);
6386 	to_proc = t->to_proc;
6387 	seq_printf(m,
6388 		   "%s %d: %pK from %d:%d to %d:%d code %x flags %x pri %ld a%d r%d elapsed %lldms",
6389 		   prefix, t->debug_id, t,
6390 		   t->from_pid,
6391 		   t->from_tid,
6392 		   to_proc ? to_proc->pid : 0,
6393 		   t->to_thread ? t->to_thread->pid : 0,
6394 		   t->code, t->flags, t->priority, t->is_async, t->is_reply,
6395 		   ktime_ms_delta(current_time, t->start_time));
6396 	spin_unlock(&t->lock);
6397 
6398 	if (proc != to_proc) {
6399 		/*
6400 		 * Can only safely deref buffer if we are holding the
6401 		 * correct proc inner lock for this node
6402 		 */
6403 		seq_puts(m, "\n");
6404 		return;
6405 	}
6406 
6407 	if (buffer == NULL) {
6408 		seq_puts(m, " buffer free\n");
6409 		return;
6410 	}
6411 	if (buffer->target_node)
6412 		seq_printf(m, " node %d", buffer->target_node->debug_id);
6413 	seq_printf(m, " size %zd:%zd offset %lx\n",
6414 		   buffer->data_size, buffer->offsets_size,
6415 		   buffer->user_data - proc->alloc.vm_start);
6416 }
6417 
print_binder_work_ilocked(struct seq_file * m,struct binder_proc * proc,const char * prefix,const char * transaction_prefix,struct binder_work * w,bool hash_ptrs)6418 static void print_binder_work_ilocked(struct seq_file *m,
6419 				      struct binder_proc *proc,
6420 				      const char *prefix,
6421 				      const char *transaction_prefix,
6422 				      struct binder_work *w, bool hash_ptrs)
6423 {
6424 	struct binder_node *node;
6425 	struct binder_transaction *t;
6426 
6427 	switch (w->type) {
6428 	case BINDER_WORK_TRANSACTION:
6429 		t = container_of(w, struct binder_transaction, work);
6430 		print_binder_transaction_ilocked(
6431 				m, proc, transaction_prefix, t);
6432 		break;
6433 	case BINDER_WORK_RETURN_ERROR: {
6434 		struct binder_error *e = container_of(
6435 				w, struct binder_error, work);
6436 
6437 		seq_printf(m, "%stransaction error: %u\n",
6438 			   prefix, e->cmd);
6439 	} break;
6440 	case BINDER_WORK_TRANSACTION_COMPLETE:
6441 		seq_printf(m, "%stransaction complete\n", prefix);
6442 		break;
6443 	case BINDER_WORK_NODE:
6444 		node = container_of(w, struct binder_node, work);
6445 		if (hash_ptrs)
6446 			seq_printf(m, "%snode work %d: u%p c%p\n",
6447 				   prefix, node->debug_id,
6448 				   (void *)(long)node->ptr,
6449 				   (void *)(long)node->cookie);
6450 		else
6451 			seq_printf(m, "%snode work %d: u%016llx c%016llx\n",
6452 				   prefix, node->debug_id,
6453 				   (u64)node->ptr, (u64)node->cookie);
6454 		break;
6455 	case BINDER_WORK_DEAD_BINDER:
6456 		seq_printf(m, "%shas dead binder\n", prefix);
6457 		break;
6458 	case BINDER_WORK_DEAD_BINDER_AND_CLEAR:
6459 		seq_printf(m, "%shas cleared dead binder\n", prefix);
6460 		break;
6461 	case BINDER_WORK_CLEAR_DEATH_NOTIFICATION:
6462 		seq_printf(m, "%shas cleared death notification\n", prefix);
6463 		break;
6464 	case BINDER_WORK_FROZEN_BINDER:
6465 		seq_printf(m, "%shas frozen binder\n", prefix);
6466 		break;
6467 	case BINDER_WORK_CLEAR_FREEZE_NOTIFICATION:
6468 		seq_printf(m, "%shas cleared freeze notification\n", prefix);
6469 		break;
6470 	default:
6471 		seq_printf(m, "%sunknown work: type %d\n", prefix, w->type);
6472 		break;
6473 	}
6474 }
6475 
print_binder_thread_ilocked(struct seq_file * m,struct binder_thread * thread,bool print_always,bool hash_ptrs)6476 static void print_binder_thread_ilocked(struct seq_file *m,
6477 					struct binder_thread *thread,
6478 					bool print_always, bool hash_ptrs)
6479 {
6480 	struct binder_transaction *t;
6481 	struct binder_work *w;
6482 	size_t start_pos = m->count;
6483 	size_t header_pos;
6484 
6485 	seq_printf(m, "  thread %d: l %02x need_return %d tr %d\n",
6486 			thread->pid, thread->looper,
6487 			thread->looper_need_return,
6488 			atomic_read(&thread->tmp_ref));
6489 	header_pos = m->count;
6490 	t = thread->transaction_stack;
6491 	while (t) {
6492 		if (t->from == thread) {
6493 			print_binder_transaction_ilocked(m, thread->proc,
6494 					"    outgoing transaction", t);
6495 			t = t->from_parent;
6496 		} else if (t->to_thread == thread) {
6497 			print_binder_transaction_ilocked(m, thread->proc,
6498 						 "    incoming transaction", t);
6499 			t = t->to_parent;
6500 		} else {
6501 			print_binder_transaction_ilocked(m, thread->proc,
6502 					"    bad transaction", t);
6503 			t = NULL;
6504 		}
6505 	}
6506 	list_for_each_entry(w, &thread->todo, entry) {
6507 		print_binder_work_ilocked(m, thread->proc, "    ",
6508 					  "    pending transaction",
6509 					  w, hash_ptrs);
6510 	}
6511 	if (!print_always && m->count == header_pos)
6512 		m->count = start_pos;
6513 }
6514 
print_binder_node_nilocked(struct seq_file * m,struct binder_node * node,bool hash_ptrs)6515 static void print_binder_node_nilocked(struct seq_file *m,
6516 				       struct binder_node *node,
6517 				       bool hash_ptrs)
6518 {
6519 	struct binder_ref *ref;
6520 	struct binder_work *w;
6521 	int count;
6522 
6523 	count = hlist_count_nodes(&node->refs);
6524 
6525 	if (hash_ptrs)
6526 		seq_printf(m, "  node %d: u%p c%p", node->debug_id,
6527 			   (void *)(long)node->ptr, (void *)(long)node->cookie);
6528 	else
6529 		seq_printf(m, "  node %d: u%016llx c%016llx", node->debug_id,
6530 			   (u64)node->ptr, (u64)node->cookie);
6531 	seq_printf(m, " hs %d hw %d ls %d lw %d is %d iw %d tr %d",
6532 		   node->has_strong_ref, node->has_weak_ref,
6533 		   node->local_strong_refs, node->local_weak_refs,
6534 		   node->internal_strong_refs, count, node->tmp_refs);
6535 	if (count) {
6536 		seq_puts(m, " proc");
6537 		hlist_for_each_entry(ref, &node->refs, node_entry)
6538 			seq_printf(m, " %d", ref->proc->pid);
6539 	}
6540 	seq_puts(m, "\n");
6541 	if (node->proc) {
6542 		list_for_each_entry(w, &node->async_todo, entry)
6543 			print_binder_work_ilocked(m, node->proc, "    ",
6544 					  "    pending async transaction",
6545 					  w, hash_ptrs);
6546 	}
6547 }
6548 
print_binder_ref_olocked(struct seq_file * m,struct binder_ref * ref)6549 static void print_binder_ref_olocked(struct seq_file *m,
6550 				     struct binder_ref *ref)
6551 {
6552 	binder_node_lock(ref->node);
6553 	seq_printf(m, "  ref %d: desc %d %snode %d s %d w %d d %pK\n",
6554 		   ref->data.debug_id, ref->data.desc,
6555 		   ref->node->proc ? "" : "dead ",
6556 		   ref->node->debug_id, ref->data.strong,
6557 		   ref->data.weak, ref->death);
6558 	binder_node_unlock(ref->node);
6559 }
6560 
6561 /**
6562  * print_next_binder_node_ilocked() - Print binder_node from a locked list
6563  * @m:          struct seq_file for output via seq_printf()
6564  * @proc:       struct binder_proc we hold the inner_proc_lock to (if any)
6565  * @node:       struct binder_node to print fields of
6566  * @prev_node:	struct binder_node we hold a temporary reference to (if any)
6567  * @hash_ptrs:  whether to hash @node's binder_uintptr_t fields
6568  *
6569  * Helper function to handle synchronization around printing a struct
6570  * binder_node while iterating through @proc->nodes or the dead nodes list.
6571  * Caller must hold either @proc->inner_lock (for live nodes) or
6572  * binder_dead_nodes_lock. This lock will be released during the body of this
6573  * function, but it will be reacquired before returning to the caller.
6574  *
6575  * Return:	pointer to the struct binder_node we hold a tmpref on
6576  */
6577 static struct binder_node *
print_next_binder_node_ilocked(struct seq_file * m,struct binder_proc * proc,struct binder_node * node,struct binder_node * prev_node,bool hash_ptrs)6578 print_next_binder_node_ilocked(struct seq_file *m, struct binder_proc *proc,
6579 			       struct binder_node *node,
6580 			       struct binder_node *prev_node, bool hash_ptrs)
6581 {
6582 	/*
6583 	 * Take a temporary reference on the node so that isn't freed while
6584 	 * we print it.
6585 	 */
6586 	binder_inc_node_tmpref_ilocked(node);
6587 	/*
6588 	 * Live nodes need to drop the inner proc lock and dead nodes need to
6589 	 * drop the binder_dead_nodes_lock before trying to take the node lock.
6590 	 */
6591 	if (proc)
6592 		binder_inner_proc_unlock(proc);
6593 	else
6594 		spin_unlock(&binder_dead_nodes_lock);
6595 	if (prev_node)
6596 		binder_put_node(prev_node);
6597 	binder_node_inner_lock(node);
6598 	print_binder_node_nilocked(m, node, hash_ptrs);
6599 	binder_node_inner_unlock(node);
6600 	if (proc)
6601 		binder_inner_proc_lock(proc);
6602 	else
6603 		spin_lock(&binder_dead_nodes_lock);
6604 	return node;
6605 }
6606 
print_binder_proc(struct seq_file * m,struct binder_proc * proc,bool print_all,bool hash_ptrs)6607 static void print_binder_proc(struct seq_file *m, struct binder_proc *proc,
6608 			      bool print_all, bool hash_ptrs)
6609 {
6610 	struct binder_work *w;
6611 	struct rb_node *n;
6612 	size_t start_pos = m->count;
6613 	size_t header_pos;
6614 	struct binder_node *last_node = NULL;
6615 
6616 	seq_printf(m, "proc %d\n", proc->pid);
6617 	seq_printf(m, "context %s\n", proc->context->name);
6618 	header_pos = m->count;
6619 
6620 	binder_inner_proc_lock(proc);
6621 	for (n = rb_first(&proc->threads); n; n = rb_next(n))
6622 		print_binder_thread_ilocked(m, rb_entry(n, struct binder_thread,
6623 						rb_node), print_all, hash_ptrs);
6624 
6625 	for (n = rb_first(&proc->nodes); n; n = rb_next(n)) {
6626 		struct binder_node *node = rb_entry(n, struct binder_node,
6627 						    rb_node);
6628 		if (!print_all && !node->has_async_transaction)
6629 			continue;
6630 
6631 		last_node = print_next_binder_node_ilocked(m, proc, node,
6632 							   last_node,
6633 							   hash_ptrs);
6634 	}
6635 	binder_inner_proc_unlock(proc);
6636 	if (last_node)
6637 		binder_put_node(last_node);
6638 
6639 	if (print_all) {
6640 		binder_proc_lock(proc);
6641 		for (n = rb_first(&proc->refs_by_desc); n; n = rb_next(n))
6642 			print_binder_ref_olocked(m, rb_entry(n,
6643 							     struct binder_ref,
6644 							     rb_node_desc));
6645 		binder_proc_unlock(proc);
6646 	}
6647 	binder_alloc_print_allocated(m, &proc->alloc);
6648 	binder_inner_proc_lock(proc);
6649 	list_for_each_entry(w, &proc->todo, entry)
6650 		print_binder_work_ilocked(m, proc, "  ",
6651 					  "  pending transaction", w,
6652 					  hash_ptrs);
6653 	list_for_each_entry(w, &proc->delivered_death, entry) {
6654 		seq_puts(m, "  has delivered dead binder\n");
6655 		break;
6656 	}
6657 	list_for_each_entry(w, &proc->delivered_freeze, entry) {
6658 		seq_puts(m, "  has delivered freeze binder\n");
6659 		break;
6660 	}
6661 	binder_inner_proc_unlock(proc);
6662 	if (!print_all && m->count == header_pos)
6663 		m->count = start_pos;
6664 }
6665 
6666 static const char * const binder_return_strings[] = {
6667 	"BR_ERROR",
6668 	"BR_OK",
6669 	"BR_TRANSACTION",
6670 	"BR_REPLY",
6671 	"BR_ACQUIRE_RESULT",
6672 	"BR_DEAD_REPLY",
6673 	"BR_TRANSACTION_COMPLETE",
6674 	"BR_INCREFS",
6675 	"BR_ACQUIRE",
6676 	"BR_RELEASE",
6677 	"BR_DECREFS",
6678 	"BR_ATTEMPT_ACQUIRE",
6679 	"BR_NOOP",
6680 	"BR_SPAWN_LOOPER",
6681 	"BR_FINISHED",
6682 	"BR_DEAD_BINDER",
6683 	"BR_CLEAR_DEATH_NOTIFICATION_DONE",
6684 	"BR_FAILED_REPLY",
6685 	"BR_FROZEN_REPLY",
6686 	"BR_ONEWAY_SPAM_SUSPECT",
6687 	"BR_TRANSACTION_PENDING_FROZEN",
6688 	"BR_FROZEN_BINDER",
6689 	"BR_CLEAR_FREEZE_NOTIFICATION_DONE",
6690 };
6691 
6692 static const char * const binder_command_strings[] = {
6693 	"BC_TRANSACTION",
6694 	"BC_REPLY",
6695 	"BC_ACQUIRE_RESULT",
6696 	"BC_FREE_BUFFER",
6697 	"BC_INCREFS",
6698 	"BC_ACQUIRE",
6699 	"BC_RELEASE",
6700 	"BC_DECREFS",
6701 	"BC_INCREFS_DONE",
6702 	"BC_ACQUIRE_DONE",
6703 	"BC_ATTEMPT_ACQUIRE",
6704 	"BC_REGISTER_LOOPER",
6705 	"BC_ENTER_LOOPER",
6706 	"BC_EXIT_LOOPER",
6707 	"BC_REQUEST_DEATH_NOTIFICATION",
6708 	"BC_CLEAR_DEATH_NOTIFICATION",
6709 	"BC_DEAD_BINDER_DONE",
6710 	"BC_TRANSACTION_SG",
6711 	"BC_REPLY_SG",
6712 	"BC_REQUEST_FREEZE_NOTIFICATION",
6713 	"BC_CLEAR_FREEZE_NOTIFICATION",
6714 	"BC_FREEZE_NOTIFICATION_DONE",
6715 };
6716 
6717 static const char * const binder_objstat_strings[] = {
6718 	"proc",
6719 	"thread",
6720 	"node",
6721 	"ref",
6722 	"death",
6723 	"transaction",
6724 	"transaction_complete",
6725 	"freeze",
6726 };
6727 
print_binder_stats(struct seq_file * m,const char * prefix,struct binder_stats * stats)6728 static void print_binder_stats(struct seq_file *m, const char *prefix,
6729 			       struct binder_stats *stats)
6730 {
6731 	int i;
6732 
6733 	BUILD_BUG_ON(ARRAY_SIZE(stats->bc) !=
6734 		     ARRAY_SIZE(binder_command_strings));
6735 	for (i = 0; i < ARRAY_SIZE(stats->bc); i++) {
6736 		int temp = atomic_read(&stats->bc[i]);
6737 
6738 		if (temp)
6739 			seq_printf(m, "%s%s: %d\n", prefix,
6740 				   binder_command_strings[i], temp);
6741 	}
6742 
6743 	BUILD_BUG_ON(ARRAY_SIZE(stats->br) !=
6744 		     ARRAY_SIZE(binder_return_strings));
6745 	for (i = 0; i < ARRAY_SIZE(stats->br); i++) {
6746 		int temp = atomic_read(&stats->br[i]);
6747 
6748 		if (temp)
6749 			seq_printf(m, "%s%s: %d\n", prefix,
6750 				   binder_return_strings[i], temp);
6751 	}
6752 
6753 	BUILD_BUG_ON(ARRAY_SIZE(stats->obj_created) !=
6754 		     ARRAY_SIZE(binder_objstat_strings));
6755 	BUILD_BUG_ON(ARRAY_SIZE(stats->obj_created) !=
6756 		     ARRAY_SIZE(stats->obj_deleted));
6757 	for (i = 0; i < ARRAY_SIZE(stats->obj_created); i++) {
6758 		int created = atomic_read(&stats->obj_created[i]);
6759 		int deleted = atomic_read(&stats->obj_deleted[i]);
6760 
6761 		if (created || deleted)
6762 			seq_printf(m, "%s%s: active %d total %d\n",
6763 				prefix,
6764 				binder_objstat_strings[i],
6765 				created - deleted,
6766 				created);
6767 	}
6768 }
6769 
print_binder_proc_stats(struct seq_file * m,struct binder_proc * proc)6770 static void print_binder_proc_stats(struct seq_file *m,
6771 				    struct binder_proc *proc)
6772 {
6773 	struct binder_work *w;
6774 	struct binder_thread *thread;
6775 	struct rb_node *n;
6776 	int count, strong, weak, ready_threads;
6777 	size_t free_async_space =
6778 		binder_alloc_get_free_async_space(&proc->alloc);
6779 
6780 	seq_printf(m, "proc %d\n", proc->pid);
6781 	seq_printf(m, "context %s\n", proc->context->name);
6782 	count = 0;
6783 	ready_threads = 0;
6784 	binder_inner_proc_lock(proc);
6785 	for (n = rb_first(&proc->threads); n; n = rb_next(n))
6786 		count++;
6787 
6788 	list_for_each_entry(thread, &proc->waiting_threads, waiting_thread_node)
6789 		ready_threads++;
6790 
6791 	seq_printf(m, "  threads: %d\n", count);
6792 	seq_printf(m, "  requested threads: %d+%d/%d\n"
6793 			"  ready threads %d\n"
6794 			"  free async space %zd\n", proc->requested_threads,
6795 			proc->requested_threads_started, proc->max_threads,
6796 			ready_threads,
6797 			free_async_space);
6798 	count = 0;
6799 	for (n = rb_first(&proc->nodes); n; n = rb_next(n))
6800 		count++;
6801 	binder_inner_proc_unlock(proc);
6802 	seq_printf(m, "  nodes: %d\n", count);
6803 	count = 0;
6804 	strong = 0;
6805 	weak = 0;
6806 	binder_proc_lock(proc);
6807 	for (n = rb_first(&proc->refs_by_desc); n; n = rb_next(n)) {
6808 		struct binder_ref *ref = rb_entry(n, struct binder_ref,
6809 						  rb_node_desc);
6810 		count++;
6811 		strong += ref->data.strong;
6812 		weak += ref->data.weak;
6813 	}
6814 	binder_proc_unlock(proc);
6815 	seq_printf(m, "  refs: %d s %d w %d\n", count, strong, weak);
6816 
6817 	count = binder_alloc_get_allocated_count(&proc->alloc);
6818 	seq_printf(m, "  buffers: %d\n", count);
6819 
6820 	binder_alloc_print_pages(m, &proc->alloc);
6821 
6822 	count = 0;
6823 	binder_inner_proc_lock(proc);
6824 	list_for_each_entry(w, &proc->todo, entry) {
6825 		if (w->type == BINDER_WORK_TRANSACTION)
6826 			count++;
6827 	}
6828 	binder_inner_proc_unlock(proc);
6829 	seq_printf(m, "  pending transactions: %d\n", count);
6830 
6831 	print_binder_stats(m, "  ", &proc->stats);
6832 }
6833 
print_binder_state(struct seq_file * m,bool hash_ptrs)6834 static void print_binder_state(struct seq_file *m, bool hash_ptrs)
6835 {
6836 	struct binder_proc *proc;
6837 	struct binder_node *node;
6838 	struct binder_node *last_node = NULL;
6839 
6840 	seq_puts(m, "binder state:\n");
6841 
6842 	spin_lock(&binder_dead_nodes_lock);
6843 	if (!hlist_empty(&binder_dead_nodes))
6844 		seq_puts(m, "dead nodes:\n");
6845 	hlist_for_each_entry(node, &binder_dead_nodes, dead_node)
6846 		last_node = print_next_binder_node_ilocked(m, NULL, node,
6847 							   last_node,
6848 							   hash_ptrs);
6849 	spin_unlock(&binder_dead_nodes_lock);
6850 	if (last_node)
6851 		binder_put_node(last_node);
6852 
6853 	mutex_lock(&binder_procs_lock);
6854 	hlist_for_each_entry(proc, &binder_procs, proc_node)
6855 		print_binder_proc(m, proc, true, hash_ptrs);
6856 	mutex_unlock(&binder_procs_lock);
6857 }
6858 
print_binder_transactions(struct seq_file * m,bool hash_ptrs)6859 static void print_binder_transactions(struct seq_file *m, bool hash_ptrs)
6860 {
6861 	struct binder_proc *proc;
6862 
6863 	seq_puts(m, "binder transactions:\n");
6864 	mutex_lock(&binder_procs_lock);
6865 	hlist_for_each_entry(proc, &binder_procs, proc_node)
6866 		print_binder_proc(m, proc, false, hash_ptrs);
6867 	mutex_unlock(&binder_procs_lock);
6868 }
6869 
state_show(struct seq_file * m,void * unused)6870 static int state_show(struct seq_file *m, void *unused)
6871 {
6872 	print_binder_state(m, false);
6873 	return 0;
6874 }
6875 
state_hashed_show(struct seq_file * m,void * unused)6876 static int state_hashed_show(struct seq_file *m, void *unused)
6877 {
6878 	print_binder_state(m, true);
6879 	return 0;
6880 }
6881 
stats_show(struct seq_file * m,void * unused)6882 static int stats_show(struct seq_file *m, void *unused)
6883 {
6884 	struct binder_proc *proc;
6885 
6886 	seq_puts(m, "binder stats:\n");
6887 
6888 	print_binder_stats(m, "", &binder_stats);
6889 
6890 	mutex_lock(&binder_procs_lock);
6891 	hlist_for_each_entry(proc, &binder_procs, proc_node)
6892 		print_binder_proc_stats(m, proc);
6893 	mutex_unlock(&binder_procs_lock);
6894 
6895 	return 0;
6896 }
6897 
transactions_show(struct seq_file * m,void * unused)6898 static int transactions_show(struct seq_file *m, void *unused)
6899 {
6900 	print_binder_transactions(m, false);
6901 	return 0;
6902 }
6903 
transactions_hashed_show(struct seq_file * m,void * unused)6904 static int transactions_hashed_show(struct seq_file *m, void *unused)
6905 {
6906 	print_binder_transactions(m, true);
6907 	return 0;
6908 }
6909 
proc_show(struct seq_file * m,void * unused)6910 static int proc_show(struct seq_file *m, void *unused)
6911 {
6912 	struct binder_proc *itr;
6913 	int pid = (unsigned long)m->private;
6914 
6915 	guard(mutex)(&binder_procs_lock);
6916 	hlist_for_each_entry(itr, &binder_procs, proc_node) {
6917 		if (itr->pid == pid) {
6918 			seq_puts(m, "binder proc state:\n");
6919 			print_binder_proc(m, itr, true, false);
6920 		}
6921 	}
6922 
6923 	return 0;
6924 }
6925 
print_binder_transaction_log_entry(struct seq_file * m,struct binder_transaction_log_entry * e)6926 static void print_binder_transaction_log_entry(struct seq_file *m,
6927 					struct binder_transaction_log_entry *e)
6928 {
6929 	int debug_id = READ_ONCE(e->debug_id_done);
6930 	/*
6931 	 * read barrier to guarantee debug_id_done read before
6932 	 * we print the log values
6933 	 */
6934 	smp_rmb();
6935 	seq_printf(m,
6936 		   "%d: %s from %d:%d to %d:%d context %s node %d handle %d size %d:%d ret %d/%d l=%d",
6937 		   e->debug_id, (e->call_type == 2) ? "reply" :
6938 		   ((e->call_type == 1) ? "async" : "call "), e->from_proc,
6939 		   e->from_thread, e->to_proc, e->to_thread, e->context_name,
6940 		   e->to_node, e->target_handle, e->data_size, e->offsets_size,
6941 		   e->return_error, e->return_error_param,
6942 		   e->return_error_line);
6943 	/*
6944 	 * read-barrier to guarantee read of debug_id_done after
6945 	 * done printing the fields of the entry
6946 	 */
6947 	smp_rmb();
6948 	seq_printf(m, debug_id && debug_id == READ_ONCE(e->debug_id_done) ?
6949 			"\n" : " (incomplete)\n");
6950 }
6951 
transaction_log_show(struct seq_file * m,void * unused)6952 static int transaction_log_show(struct seq_file *m, void *unused)
6953 {
6954 	struct binder_transaction_log *log = m->private;
6955 	unsigned int log_cur = atomic_read(&log->cur);
6956 	unsigned int count;
6957 	unsigned int cur;
6958 	int i;
6959 
6960 	count = log_cur + 1;
6961 	cur = count < ARRAY_SIZE(log->entry) && !log->full ?
6962 		0 : count % ARRAY_SIZE(log->entry);
6963 	if (count > ARRAY_SIZE(log->entry) || log->full)
6964 		count = ARRAY_SIZE(log->entry);
6965 	for (i = 0; i < count; i++) {
6966 		unsigned int index = cur++ % ARRAY_SIZE(log->entry);
6967 
6968 		print_binder_transaction_log_entry(m, &log->entry[index]);
6969 	}
6970 	return 0;
6971 }
6972 
6973 const struct file_operations binder_fops = {
6974 	.owner = THIS_MODULE,
6975 	.poll = binder_poll,
6976 	.unlocked_ioctl = binder_ioctl,
6977 	.compat_ioctl = compat_ptr_ioctl,
6978 	.mmap = binder_mmap,
6979 	.open = binder_open,
6980 	.flush = binder_flush,
6981 	.release = binder_release,
6982 };
6983 
6984 DEFINE_SHOW_ATTRIBUTE(state);
6985 DEFINE_SHOW_ATTRIBUTE(state_hashed);
6986 DEFINE_SHOW_ATTRIBUTE(stats);
6987 DEFINE_SHOW_ATTRIBUTE(transactions);
6988 DEFINE_SHOW_ATTRIBUTE(transactions_hashed);
6989 DEFINE_SHOW_ATTRIBUTE(transaction_log);
6990 
6991 const struct binder_debugfs_entry binder_debugfs_entries[] = {
6992 	{
6993 		.name = "state",
6994 		.mode = 0444,
6995 		.fops = &state_fops,
6996 		.data = NULL,
6997 	},
6998 	{
6999 		.name = "state_hashed",
7000 		.mode = 0444,
7001 		.fops = &state_hashed_fops,
7002 		.data = NULL,
7003 	},
7004 	{
7005 		.name = "stats",
7006 		.mode = 0444,
7007 		.fops = &stats_fops,
7008 		.data = NULL,
7009 	},
7010 	{
7011 		.name = "transactions",
7012 		.mode = 0444,
7013 		.fops = &transactions_fops,
7014 		.data = NULL,
7015 	},
7016 	{
7017 		.name = "transactions_hashed",
7018 		.mode = 0444,
7019 		.fops = &transactions_hashed_fops,
7020 		.data = NULL,
7021 	},
7022 	{
7023 		.name = "transaction_log",
7024 		.mode = 0444,
7025 		.fops = &transaction_log_fops,
7026 		.data = &binder_transaction_log,
7027 	},
7028 	{
7029 		.name = "failed_transaction_log",
7030 		.mode = 0444,
7031 		.fops = &transaction_log_fops,
7032 		.data = &binder_transaction_log_failed,
7033 	},
7034 	{} /* terminator */
7035 };
7036 
binder_add_device(struct binder_device * device)7037 void binder_add_device(struct binder_device *device)
7038 {
7039 	guard(spinlock)(&binder_devices_lock);
7040 	hlist_add_head(&device->hlist, &binder_devices);
7041 }
7042 
binder_remove_device(struct binder_device * device)7043 void binder_remove_device(struct binder_device *device)
7044 {
7045 	guard(spinlock)(&binder_devices_lock);
7046 	hlist_del_init(&device->hlist);
7047 }
7048 
init_binder_device(const char * name)7049 static int __init init_binder_device(const char *name)
7050 {
7051 	int ret;
7052 	struct binder_device *binder_device;
7053 
7054 	binder_device = kzalloc(sizeof(*binder_device), GFP_KERNEL);
7055 	if (!binder_device)
7056 		return -ENOMEM;
7057 
7058 	binder_device->miscdev.fops = &binder_fops;
7059 	binder_device->miscdev.minor = MISC_DYNAMIC_MINOR;
7060 	binder_device->miscdev.name = name;
7061 
7062 	refcount_set(&binder_device->ref, 1);
7063 	binder_device->context.binder_context_mgr_uid = INVALID_UID;
7064 	binder_device->context.name = name;
7065 	mutex_init(&binder_device->context.context_mgr_node_lock);
7066 
7067 	ret = misc_register(&binder_device->miscdev);
7068 	if (ret < 0) {
7069 		kfree(binder_device);
7070 		return ret;
7071 	}
7072 
7073 	binder_add_device(binder_device);
7074 
7075 	return ret;
7076 }
7077 
binder_init(void)7078 static int __init binder_init(void)
7079 {
7080 	int ret;
7081 	char *device_name, *device_tmp;
7082 	struct binder_device *device;
7083 	struct hlist_node *tmp;
7084 	char *device_names = NULL;
7085 	const struct binder_debugfs_entry *db_entry;
7086 
7087 	ret = binder_alloc_shrinker_init();
7088 	if (ret)
7089 		return ret;
7090 
7091 	atomic_set(&binder_transaction_log.cur, ~0U);
7092 	atomic_set(&binder_transaction_log_failed.cur, ~0U);
7093 
7094 	binder_debugfs_dir_entry_root = debugfs_create_dir("binder", NULL);
7095 
7096 	binder_for_each_debugfs_entry(db_entry)
7097 		debugfs_create_file(db_entry->name,
7098 					db_entry->mode,
7099 					binder_debugfs_dir_entry_root,
7100 					db_entry->data,
7101 					db_entry->fops);
7102 
7103 	binder_debugfs_dir_entry_proc = debugfs_create_dir("proc",
7104 						binder_debugfs_dir_entry_root);
7105 
7106 	if (!IS_ENABLED(CONFIG_ANDROID_BINDERFS) &&
7107 	    strcmp(binder_devices_param, "") != 0) {
7108 		/*
7109 		* Copy the module_parameter string, because we don't want to
7110 		* tokenize it in-place.
7111 		 */
7112 		device_names = kstrdup(binder_devices_param, GFP_KERNEL);
7113 		if (!device_names) {
7114 			ret = -ENOMEM;
7115 			goto err_alloc_device_names_failed;
7116 		}
7117 
7118 		device_tmp = device_names;
7119 		while ((device_name = strsep(&device_tmp, ","))) {
7120 			ret = init_binder_device(device_name);
7121 			if (ret)
7122 				goto err_init_binder_device_failed;
7123 		}
7124 	}
7125 
7126 	ret = genl_register_family(&binder_nl_family);
7127 	if (ret)
7128 		goto err_init_binder_device_failed;
7129 
7130 	ret = init_binderfs();
7131 	if (ret)
7132 		goto err_init_binderfs_failed;
7133 
7134 	return ret;
7135 
7136 err_init_binderfs_failed:
7137 	genl_unregister_family(&binder_nl_family);
7138 
7139 err_init_binder_device_failed:
7140 	hlist_for_each_entry_safe(device, tmp, &binder_devices, hlist) {
7141 		misc_deregister(&device->miscdev);
7142 		binder_remove_device(device);
7143 		kfree(device);
7144 	}
7145 
7146 	kfree(device_names);
7147 
7148 err_alloc_device_names_failed:
7149 	debugfs_remove_recursive(binder_debugfs_dir_entry_root);
7150 	binder_alloc_shrinker_exit();
7151 
7152 	return ret;
7153 }
7154 
7155 device_initcall(binder_init);
7156 
7157 #define CREATE_TRACE_POINTS
7158 #include "binder_trace.h"
7159