xref: /linux/security/security.c (revision 9238311176115aac1b1a86e8e968c04ebec747a1)
1 // SPDX-License-Identifier: GPL-2.0-or-later
2 /*
3  * Security plug functions
4  *
5  * Copyright (C) 2001 WireX Communications, Inc <chris@wirex.com>
6  * Copyright (C) 2001-2002 Greg Kroah-Hartman <greg@kroah.com>
7  * Copyright (C) 2001 Networks Associates Technology, Inc <ssmalley@nai.com>
8  * Copyright (C) 2016 Mellanox Technologies
9  * Copyright (C) 2023 Microsoft Corporation <paul@paul-moore.com>
10  */
11 
12 #define pr_fmt(fmt) "LSM: " fmt
13 
14 #include <linux/bpf.h>
15 #include <linux/capability.h>
16 #include <linux/dcache.h>
17 #include <linux/export.h>
18 #include <linux/init.h>
19 #include <linux/kernel.h>
20 #include <linux/kernel_read_file.h>
21 #include <linux/lsm_hooks.h>
22 #include <linux/integrity.h>
23 #include <linux/fsnotify.h>
24 #include <linux/mman.h>
25 #include <linux/mount.h>
26 #include <linux/personality.h>
27 #include <linux/backing-dev.h>
28 #include <linux/string.h>
29 #include <linux/xattr.h>
30 #include <linux/msg.h>
31 #include <net/flow.h>
32 
33 /* How many LSMs were built into the kernel? */
34 #define LSM_COUNT (__end_lsm_info - __start_lsm_info)
35 
36 /*
37  * How many LSMs are built into the kernel as determined at
38  * build time. Used to determine fixed array sizes.
39  * The capability module is accounted for by CONFIG_SECURITY
40  */
41 #define LSM_CONFIG_COUNT ( \
42 	(IS_ENABLED(CONFIG_SECURITY) ? 1 : 0) + \
43 	(IS_ENABLED(CONFIG_SECURITY_SELINUX) ? 1 : 0) + \
44 	(IS_ENABLED(CONFIG_SECURITY_SMACK) ? 1 : 0) + \
45 	(IS_ENABLED(CONFIG_SECURITY_TOMOYO) ? 1 : 0) + \
46 	(IS_ENABLED(CONFIG_SECURITY_APPARMOR) ? 1 : 0) + \
47 	(IS_ENABLED(CONFIG_SECURITY_YAMA) ? 1 : 0) + \
48 	(IS_ENABLED(CONFIG_SECURITY_LOADPIN) ? 1 : 0) + \
49 	(IS_ENABLED(CONFIG_SECURITY_SAFESETID) ? 1 : 0) + \
50 	(IS_ENABLED(CONFIG_SECURITY_LOCKDOWN_LSM) ? 1 : 0) + \
51 	(IS_ENABLED(CONFIG_BPF_LSM) ? 1 : 0) + \
52 	(IS_ENABLED(CONFIG_SECURITY_LANDLOCK) ? 1 : 0) + \
53 	(IS_ENABLED(CONFIG_IMA) ? 1 : 0) + \
54 	(IS_ENABLED(CONFIG_EVM) ? 1 : 0))
55 
56 /*
57  * These are descriptions of the reasons that can be passed to the
58  * security_locked_down() LSM hook. Placing this array here allows
59  * all security modules to use the same descriptions for auditing
60  * purposes.
61  */
62 const char *const lockdown_reasons[LOCKDOWN_CONFIDENTIALITY_MAX + 1] = {
63 	[LOCKDOWN_NONE] = "none",
64 	[LOCKDOWN_MODULE_SIGNATURE] = "unsigned module loading",
65 	[LOCKDOWN_DEV_MEM] = "/dev/mem,kmem,port",
66 	[LOCKDOWN_EFI_TEST] = "/dev/efi_test access",
67 	[LOCKDOWN_KEXEC] = "kexec of unsigned images",
68 	[LOCKDOWN_HIBERNATION] = "hibernation",
69 	[LOCKDOWN_PCI_ACCESS] = "direct PCI access",
70 	[LOCKDOWN_IOPORT] = "raw io port access",
71 	[LOCKDOWN_MSR] = "raw MSR access",
72 	[LOCKDOWN_ACPI_TABLES] = "modifying ACPI tables",
73 	[LOCKDOWN_DEVICE_TREE] = "modifying device tree contents",
74 	[LOCKDOWN_PCMCIA_CIS] = "direct PCMCIA CIS storage",
75 	[LOCKDOWN_TIOCSSERIAL] = "reconfiguration of serial port IO",
76 	[LOCKDOWN_MODULE_PARAMETERS] = "unsafe module parameters",
77 	[LOCKDOWN_MMIOTRACE] = "unsafe mmio",
78 	[LOCKDOWN_DEBUGFS] = "debugfs access",
79 	[LOCKDOWN_XMON_WR] = "xmon write access",
80 	[LOCKDOWN_BPF_WRITE_USER] = "use of bpf to write user RAM",
81 	[LOCKDOWN_DBG_WRITE_KERNEL] = "use of kgdb/kdb to write kernel RAM",
82 	[LOCKDOWN_RTAS_ERROR_INJECTION] = "RTAS error injection",
83 	[LOCKDOWN_INTEGRITY_MAX] = "integrity",
84 	[LOCKDOWN_KCORE] = "/proc/kcore access",
85 	[LOCKDOWN_KPROBES] = "use of kprobes",
86 	[LOCKDOWN_BPF_READ_KERNEL] = "use of bpf to read kernel RAM",
87 	[LOCKDOWN_DBG_READ_KERNEL] = "use of kgdb/kdb to read kernel RAM",
88 	[LOCKDOWN_PERF] = "unsafe use of perf",
89 	[LOCKDOWN_TRACEFS] = "use of tracefs",
90 	[LOCKDOWN_XMON_RW] = "xmon read and write access",
91 	[LOCKDOWN_XFRM_SECRET] = "xfrm SA secret",
92 	[LOCKDOWN_CONFIDENTIALITY_MAX] = "confidentiality",
93 };
94 
95 struct security_hook_heads security_hook_heads __ro_after_init;
96 static BLOCKING_NOTIFIER_HEAD(blocking_lsm_notifier_chain);
97 
98 static struct kmem_cache *lsm_file_cache;
99 static struct kmem_cache *lsm_inode_cache;
100 
101 char *lsm_names;
102 static struct lsm_blob_sizes blob_sizes __ro_after_init;
103 
104 /* Boot-time LSM user choice */
105 static __initdata const char *chosen_lsm_order;
106 static __initdata const char *chosen_major_lsm;
107 
108 static __initconst const char *const builtin_lsm_order = CONFIG_LSM;
109 
110 /* Ordered list of LSMs to initialize. */
111 static __initdata struct lsm_info **ordered_lsms;
112 static __initdata struct lsm_info *exclusive;
113 
114 static __initdata bool debug;
115 #define init_debug(...)						\
116 	do {							\
117 		if (debug)					\
118 			pr_info(__VA_ARGS__);			\
119 	} while (0)
120 
121 static bool __init is_enabled(struct lsm_info *lsm)
122 {
123 	if (!lsm->enabled)
124 		return false;
125 
126 	return *lsm->enabled;
127 }
128 
129 /* Mark an LSM's enabled flag. */
130 static int lsm_enabled_true __initdata = 1;
131 static int lsm_enabled_false __initdata = 0;
132 static void __init set_enabled(struct lsm_info *lsm, bool enabled)
133 {
134 	/*
135 	 * When an LSM hasn't configured an enable variable, we can use
136 	 * a hard-coded location for storing the default enabled state.
137 	 */
138 	if (!lsm->enabled) {
139 		if (enabled)
140 			lsm->enabled = &lsm_enabled_true;
141 		else
142 			lsm->enabled = &lsm_enabled_false;
143 	} else if (lsm->enabled == &lsm_enabled_true) {
144 		if (!enabled)
145 			lsm->enabled = &lsm_enabled_false;
146 	} else if (lsm->enabled == &lsm_enabled_false) {
147 		if (enabled)
148 			lsm->enabled = &lsm_enabled_true;
149 	} else {
150 		*lsm->enabled = enabled;
151 	}
152 }
153 
154 /* Is an LSM already listed in the ordered LSMs list? */
155 static bool __init exists_ordered_lsm(struct lsm_info *lsm)
156 {
157 	struct lsm_info **check;
158 
159 	for (check = ordered_lsms; *check; check++)
160 		if (*check == lsm)
161 			return true;
162 
163 	return false;
164 }
165 
166 /* Append an LSM to the list of ordered LSMs to initialize. */
167 static int last_lsm __initdata;
168 static void __init append_ordered_lsm(struct lsm_info *lsm, const char *from)
169 {
170 	/* Ignore duplicate selections. */
171 	if (exists_ordered_lsm(lsm))
172 		return;
173 
174 	if (WARN(last_lsm == LSM_COUNT, "%s: out of LSM slots!?\n", from))
175 		return;
176 
177 	/* Enable this LSM, if it is not already set. */
178 	if (!lsm->enabled)
179 		lsm->enabled = &lsm_enabled_true;
180 	ordered_lsms[last_lsm++] = lsm;
181 
182 	init_debug("%s ordered: %s (%s)\n", from, lsm->name,
183 		   is_enabled(lsm) ? "enabled" : "disabled");
184 }
185 
186 /* Is an LSM allowed to be initialized? */
187 static bool __init lsm_allowed(struct lsm_info *lsm)
188 {
189 	/* Skip if the LSM is disabled. */
190 	if (!is_enabled(lsm))
191 		return false;
192 
193 	/* Not allowed if another exclusive LSM already initialized. */
194 	if ((lsm->flags & LSM_FLAG_EXCLUSIVE) && exclusive) {
195 		init_debug("exclusive disabled: %s\n", lsm->name);
196 		return false;
197 	}
198 
199 	return true;
200 }
201 
202 static void __init lsm_set_blob_size(int *need, int *lbs)
203 {
204 	int offset;
205 
206 	if (*need <= 0)
207 		return;
208 
209 	offset = ALIGN(*lbs, sizeof(void *));
210 	*lbs = offset + *need;
211 	*need = offset;
212 }
213 
214 static void __init lsm_set_blob_sizes(struct lsm_blob_sizes *needed)
215 {
216 	if (!needed)
217 		return;
218 
219 	lsm_set_blob_size(&needed->lbs_cred, &blob_sizes.lbs_cred);
220 	lsm_set_blob_size(&needed->lbs_file, &blob_sizes.lbs_file);
221 	/*
222 	 * The inode blob gets an rcu_head in addition to
223 	 * what the modules might need.
224 	 */
225 	if (needed->lbs_inode && blob_sizes.lbs_inode == 0)
226 		blob_sizes.lbs_inode = sizeof(struct rcu_head);
227 	lsm_set_blob_size(&needed->lbs_inode, &blob_sizes.lbs_inode);
228 	lsm_set_blob_size(&needed->lbs_ipc, &blob_sizes.lbs_ipc);
229 	lsm_set_blob_size(&needed->lbs_msg_msg, &blob_sizes.lbs_msg_msg);
230 	lsm_set_blob_size(&needed->lbs_superblock, &blob_sizes.lbs_superblock);
231 	lsm_set_blob_size(&needed->lbs_task, &blob_sizes.lbs_task);
232 	lsm_set_blob_size(&needed->lbs_xattr_count,
233 			  &blob_sizes.lbs_xattr_count);
234 }
235 
236 /* Prepare LSM for initialization. */
237 static void __init prepare_lsm(struct lsm_info *lsm)
238 {
239 	int enabled = lsm_allowed(lsm);
240 
241 	/* Record enablement (to handle any following exclusive LSMs). */
242 	set_enabled(lsm, enabled);
243 
244 	/* If enabled, do pre-initialization work. */
245 	if (enabled) {
246 		if ((lsm->flags & LSM_FLAG_EXCLUSIVE) && !exclusive) {
247 			exclusive = lsm;
248 			init_debug("exclusive chosen:   %s\n", lsm->name);
249 		}
250 
251 		lsm_set_blob_sizes(lsm->blobs);
252 	}
253 }
254 
255 /* Initialize a given LSM, if it is enabled. */
256 static void __init initialize_lsm(struct lsm_info *lsm)
257 {
258 	if (is_enabled(lsm)) {
259 		int ret;
260 
261 		init_debug("initializing %s\n", lsm->name);
262 		ret = lsm->init();
263 		WARN(ret, "%s failed to initialize: %d\n", lsm->name, ret);
264 	}
265 }
266 
267 /*
268  * Current index to use while initializing the lsm id list.
269  */
270 u32 lsm_active_cnt __ro_after_init;
271 const struct lsm_id *lsm_idlist[LSM_CONFIG_COUNT];
272 
273 /* Populate ordered LSMs list from comma-separated LSM name list. */
274 static void __init ordered_lsm_parse(const char *order, const char *origin)
275 {
276 	struct lsm_info *lsm;
277 	char *sep, *name, *next;
278 
279 	/* LSM_ORDER_FIRST is always first. */
280 	for (lsm = __start_lsm_info; lsm < __end_lsm_info; lsm++) {
281 		if (lsm->order == LSM_ORDER_FIRST)
282 			append_ordered_lsm(lsm, "  first");
283 	}
284 
285 	/* Process "security=", if given. */
286 	if (chosen_major_lsm) {
287 		struct lsm_info *major;
288 
289 		/*
290 		 * To match the original "security=" behavior, this
291 		 * explicitly does NOT fallback to another Legacy Major
292 		 * if the selected one was separately disabled: disable
293 		 * all non-matching Legacy Major LSMs.
294 		 */
295 		for (major = __start_lsm_info; major < __end_lsm_info;
296 		     major++) {
297 			if ((major->flags & LSM_FLAG_LEGACY_MAJOR) &&
298 			    strcmp(major->name, chosen_major_lsm) != 0) {
299 				set_enabled(major, false);
300 				init_debug("security=%s disabled: %s (only one legacy major LSM)\n",
301 					   chosen_major_lsm, major->name);
302 			}
303 		}
304 	}
305 
306 	sep = kstrdup(order, GFP_KERNEL);
307 	next = sep;
308 	/* Walk the list, looking for matching LSMs. */
309 	while ((name = strsep(&next, ",")) != NULL) {
310 		bool found = false;
311 
312 		for (lsm = __start_lsm_info; lsm < __end_lsm_info; lsm++) {
313 			if (strcmp(lsm->name, name) == 0) {
314 				if (lsm->order == LSM_ORDER_MUTABLE)
315 					append_ordered_lsm(lsm, origin);
316 				found = true;
317 			}
318 		}
319 
320 		if (!found)
321 			init_debug("%s ignored: %s (not built into kernel)\n",
322 				   origin, name);
323 	}
324 
325 	/* Process "security=", if given. */
326 	if (chosen_major_lsm) {
327 		for (lsm = __start_lsm_info; lsm < __end_lsm_info; lsm++) {
328 			if (exists_ordered_lsm(lsm))
329 				continue;
330 			if (strcmp(lsm->name, chosen_major_lsm) == 0)
331 				append_ordered_lsm(lsm, "security=");
332 		}
333 	}
334 
335 	/* LSM_ORDER_LAST is always last. */
336 	for (lsm = __start_lsm_info; lsm < __end_lsm_info; lsm++) {
337 		if (lsm->order == LSM_ORDER_LAST)
338 			append_ordered_lsm(lsm, "   last");
339 	}
340 
341 	/* Disable all LSMs not in the ordered list. */
342 	for (lsm = __start_lsm_info; lsm < __end_lsm_info; lsm++) {
343 		if (exists_ordered_lsm(lsm))
344 			continue;
345 		set_enabled(lsm, false);
346 		init_debug("%s skipped: %s (not in requested order)\n",
347 			   origin, lsm->name);
348 	}
349 
350 	kfree(sep);
351 }
352 
353 static void __init lsm_early_cred(struct cred *cred);
354 static void __init lsm_early_task(struct task_struct *task);
355 
356 static int lsm_append(const char *new, char **result);
357 
358 static void __init report_lsm_order(void)
359 {
360 	struct lsm_info **lsm, *early;
361 	int first = 0;
362 
363 	pr_info("initializing lsm=");
364 
365 	/* Report each enabled LSM name, comma separated. */
366 	for (early = __start_early_lsm_info;
367 	     early < __end_early_lsm_info; early++)
368 		if (is_enabled(early))
369 			pr_cont("%s%s", first++ == 0 ? "" : ",", early->name);
370 	for (lsm = ordered_lsms; *lsm; lsm++)
371 		if (is_enabled(*lsm))
372 			pr_cont("%s%s", first++ == 0 ? "" : ",", (*lsm)->name);
373 
374 	pr_cont("\n");
375 }
376 
377 static void __init ordered_lsm_init(void)
378 {
379 	struct lsm_info **lsm;
380 
381 	ordered_lsms = kcalloc(LSM_COUNT + 1, sizeof(*ordered_lsms),
382 			       GFP_KERNEL);
383 
384 	if (chosen_lsm_order) {
385 		if (chosen_major_lsm) {
386 			pr_warn("security=%s is ignored because it is superseded by lsm=%s\n",
387 				chosen_major_lsm, chosen_lsm_order);
388 			chosen_major_lsm = NULL;
389 		}
390 		ordered_lsm_parse(chosen_lsm_order, "cmdline");
391 	} else
392 		ordered_lsm_parse(builtin_lsm_order, "builtin");
393 
394 	for (lsm = ordered_lsms; *lsm; lsm++)
395 		prepare_lsm(*lsm);
396 
397 	report_lsm_order();
398 
399 	init_debug("cred blob size       = %d\n", blob_sizes.lbs_cred);
400 	init_debug("file blob size       = %d\n", blob_sizes.lbs_file);
401 	init_debug("inode blob size      = %d\n", blob_sizes.lbs_inode);
402 	init_debug("ipc blob size        = %d\n", blob_sizes.lbs_ipc);
403 	init_debug("msg_msg blob size    = %d\n", blob_sizes.lbs_msg_msg);
404 	init_debug("superblock blob size = %d\n", blob_sizes.lbs_superblock);
405 	init_debug("task blob size       = %d\n", blob_sizes.lbs_task);
406 	init_debug("xattr slots          = %d\n", blob_sizes.lbs_xattr_count);
407 
408 	/*
409 	 * Create any kmem_caches needed for blobs
410 	 */
411 	if (blob_sizes.lbs_file)
412 		lsm_file_cache = kmem_cache_create("lsm_file_cache",
413 						   blob_sizes.lbs_file, 0,
414 						   SLAB_PANIC, NULL);
415 	if (blob_sizes.lbs_inode)
416 		lsm_inode_cache = kmem_cache_create("lsm_inode_cache",
417 						    blob_sizes.lbs_inode, 0,
418 						    SLAB_PANIC, NULL);
419 
420 	lsm_early_cred((struct cred *) current->cred);
421 	lsm_early_task(current);
422 	for (lsm = ordered_lsms; *lsm; lsm++)
423 		initialize_lsm(*lsm);
424 
425 	kfree(ordered_lsms);
426 }
427 
428 int __init early_security_init(void)
429 {
430 	struct lsm_info *lsm;
431 
432 #define LSM_HOOK(RET, DEFAULT, NAME, ...) \
433 	INIT_HLIST_HEAD(&security_hook_heads.NAME);
434 #include "linux/lsm_hook_defs.h"
435 #undef LSM_HOOK
436 
437 	for (lsm = __start_early_lsm_info; lsm < __end_early_lsm_info; lsm++) {
438 		if (!lsm->enabled)
439 			lsm->enabled = &lsm_enabled_true;
440 		prepare_lsm(lsm);
441 		initialize_lsm(lsm);
442 	}
443 
444 	return 0;
445 }
446 
447 /**
448  * security_init - initializes the security framework
449  *
450  * This should be called early in the kernel initialization sequence.
451  */
452 int __init security_init(void)
453 {
454 	struct lsm_info *lsm;
455 
456 	init_debug("legacy security=%s\n", chosen_major_lsm ? : " *unspecified*");
457 	init_debug("  CONFIG_LSM=%s\n", builtin_lsm_order);
458 	init_debug("boot arg lsm=%s\n", chosen_lsm_order ? : " *unspecified*");
459 
460 	/*
461 	 * Append the names of the early LSM modules now that kmalloc() is
462 	 * available
463 	 */
464 	for (lsm = __start_early_lsm_info; lsm < __end_early_lsm_info; lsm++) {
465 		init_debug("  early started: %s (%s)\n", lsm->name,
466 			   is_enabled(lsm) ? "enabled" : "disabled");
467 		if (lsm->enabled)
468 			lsm_append(lsm->name, &lsm_names);
469 	}
470 
471 	/* Load LSMs in specified order. */
472 	ordered_lsm_init();
473 
474 	return 0;
475 }
476 
477 /* Save user chosen LSM */
478 static int __init choose_major_lsm(char *str)
479 {
480 	chosen_major_lsm = str;
481 	return 1;
482 }
483 __setup("security=", choose_major_lsm);
484 
485 /* Explicitly choose LSM initialization order. */
486 static int __init choose_lsm_order(char *str)
487 {
488 	chosen_lsm_order = str;
489 	return 1;
490 }
491 __setup("lsm=", choose_lsm_order);
492 
493 /* Enable LSM order debugging. */
494 static int __init enable_debug(char *str)
495 {
496 	debug = true;
497 	return 1;
498 }
499 __setup("lsm.debug", enable_debug);
500 
501 static bool match_last_lsm(const char *list, const char *lsm)
502 {
503 	const char *last;
504 
505 	if (WARN_ON(!list || !lsm))
506 		return false;
507 	last = strrchr(list, ',');
508 	if (last)
509 		/* Pass the comma, strcmp() will check for '\0' */
510 		last++;
511 	else
512 		last = list;
513 	return !strcmp(last, lsm);
514 }
515 
516 static int lsm_append(const char *new, char **result)
517 {
518 	char *cp;
519 
520 	if (*result == NULL) {
521 		*result = kstrdup(new, GFP_KERNEL);
522 		if (*result == NULL)
523 			return -ENOMEM;
524 	} else {
525 		/* Check if it is the last registered name */
526 		if (match_last_lsm(*result, new))
527 			return 0;
528 		cp = kasprintf(GFP_KERNEL, "%s,%s", *result, new);
529 		if (cp == NULL)
530 			return -ENOMEM;
531 		kfree(*result);
532 		*result = cp;
533 	}
534 	return 0;
535 }
536 
537 /**
538  * security_add_hooks - Add a modules hooks to the hook lists.
539  * @hooks: the hooks to add
540  * @count: the number of hooks to add
541  * @lsmid: the identification information for the security module
542  *
543  * Each LSM has to register its hooks with the infrastructure.
544  */
545 void __init security_add_hooks(struct security_hook_list *hooks, int count,
546 			       const struct lsm_id *lsmid)
547 {
548 	int i;
549 
550 	/*
551 	 * A security module may call security_add_hooks() more
552 	 * than once during initialization, and LSM initialization
553 	 * is serialized. Landlock is one such case.
554 	 * Look at the previous entry, if there is one, for duplication.
555 	 */
556 	if (lsm_active_cnt == 0 || lsm_idlist[lsm_active_cnt - 1] != lsmid) {
557 		if (lsm_active_cnt >= LSM_CONFIG_COUNT)
558 			panic("%s Too many LSMs registered.\n", __func__);
559 		lsm_idlist[lsm_active_cnt++] = lsmid;
560 	}
561 
562 	for (i = 0; i < count; i++) {
563 		hooks[i].lsmid = lsmid;
564 		hlist_add_tail_rcu(&hooks[i].list, hooks[i].head);
565 	}
566 
567 	/*
568 	 * Don't try to append during early_security_init(), we'll come back
569 	 * and fix this up afterwards.
570 	 */
571 	if (slab_is_available()) {
572 		if (lsm_append(lsmid->name, &lsm_names) < 0)
573 			panic("%s - Cannot get early memory.\n", __func__);
574 	}
575 }
576 
577 int call_blocking_lsm_notifier(enum lsm_event event, void *data)
578 {
579 	return blocking_notifier_call_chain(&blocking_lsm_notifier_chain,
580 					    event, data);
581 }
582 EXPORT_SYMBOL(call_blocking_lsm_notifier);
583 
584 int register_blocking_lsm_notifier(struct notifier_block *nb)
585 {
586 	return blocking_notifier_chain_register(&blocking_lsm_notifier_chain,
587 						nb);
588 }
589 EXPORT_SYMBOL(register_blocking_lsm_notifier);
590 
591 int unregister_blocking_lsm_notifier(struct notifier_block *nb)
592 {
593 	return blocking_notifier_chain_unregister(&blocking_lsm_notifier_chain,
594 						  nb);
595 }
596 EXPORT_SYMBOL(unregister_blocking_lsm_notifier);
597 
598 /**
599  * lsm_cred_alloc - allocate a composite cred blob
600  * @cred: the cred that needs a blob
601  * @gfp: allocation type
602  *
603  * Allocate the cred blob for all the modules
604  *
605  * Returns 0, or -ENOMEM if memory can't be allocated.
606  */
607 static int lsm_cred_alloc(struct cred *cred, gfp_t gfp)
608 {
609 	if (blob_sizes.lbs_cred == 0) {
610 		cred->security = NULL;
611 		return 0;
612 	}
613 
614 	cred->security = kzalloc(blob_sizes.lbs_cred, gfp);
615 	if (cred->security == NULL)
616 		return -ENOMEM;
617 	return 0;
618 }
619 
620 /**
621  * lsm_early_cred - during initialization allocate a composite cred blob
622  * @cred: the cred that needs a blob
623  *
624  * Allocate the cred blob for all the modules
625  */
626 static void __init lsm_early_cred(struct cred *cred)
627 {
628 	int rc = lsm_cred_alloc(cred, GFP_KERNEL);
629 
630 	if (rc)
631 		panic("%s: Early cred alloc failed.\n", __func__);
632 }
633 
634 /**
635  * lsm_file_alloc - allocate a composite file blob
636  * @file: the file that needs a blob
637  *
638  * Allocate the file blob for all the modules
639  *
640  * Returns 0, or -ENOMEM if memory can't be allocated.
641  */
642 static int lsm_file_alloc(struct file *file)
643 {
644 	if (!lsm_file_cache) {
645 		file->f_security = NULL;
646 		return 0;
647 	}
648 
649 	file->f_security = kmem_cache_zalloc(lsm_file_cache, GFP_KERNEL);
650 	if (file->f_security == NULL)
651 		return -ENOMEM;
652 	return 0;
653 }
654 
655 /**
656  * lsm_inode_alloc - allocate a composite inode blob
657  * @inode: the inode that needs a blob
658  *
659  * Allocate the inode blob for all the modules
660  *
661  * Returns 0, or -ENOMEM if memory can't be allocated.
662  */
663 int lsm_inode_alloc(struct inode *inode)
664 {
665 	if (!lsm_inode_cache) {
666 		inode->i_security = NULL;
667 		return 0;
668 	}
669 
670 	inode->i_security = kmem_cache_zalloc(lsm_inode_cache, GFP_NOFS);
671 	if (inode->i_security == NULL)
672 		return -ENOMEM;
673 	return 0;
674 }
675 
676 /**
677  * lsm_task_alloc - allocate a composite task blob
678  * @task: the task that needs a blob
679  *
680  * Allocate the task blob for all the modules
681  *
682  * Returns 0, or -ENOMEM if memory can't be allocated.
683  */
684 static int lsm_task_alloc(struct task_struct *task)
685 {
686 	if (blob_sizes.lbs_task == 0) {
687 		task->security = NULL;
688 		return 0;
689 	}
690 
691 	task->security = kzalloc(blob_sizes.lbs_task, GFP_KERNEL);
692 	if (task->security == NULL)
693 		return -ENOMEM;
694 	return 0;
695 }
696 
697 /**
698  * lsm_ipc_alloc - allocate a composite ipc blob
699  * @kip: the ipc that needs a blob
700  *
701  * Allocate the ipc blob for all the modules
702  *
703  * Returns 0, or -ENOMEM if memory can't be allocated.
704  */
705 static int lsm_ipc_alloc(struct kern_ipc_perm *kip)
706 {
707 	if (blob_sizes.lbs_ipc == 0) {
708 		kip->security = NULL;
709 		return 0;
710 	}
711 
712 	kip->security = kzalloc(blob_sizes.lbs_ipc, GFP_KERNEL);
713 	if (kip->security == NULL)
714 		return -ENOMEM;
715 	return 0;
716 }
717 
718 /**
719  * lsm_msg_msg_alloc - allocate a composite msg_msg blob
720  * @mp: the msg_msg that needs a blob
721  *
722  * Allocate the ipc blob for all the modules
723  *
724  * Returns 0, or -ENOMEM if memory can't be allocated.
725  */
726 static int lsm_msg_msg_alloc(struct msg_msg *mp)
727 {
728 	if (blob_sizes.lbs_msg_msg == 0) {
729 		mp->security = NULL;
730 		return 0;
731 	}
732 
733 	mp->security = kzalloc(blob_sizes.lbs_msg_msg, GFP_KERNEL);
734 	if (mp->security == NULL)
735 		return -ENOMEM;
736 	return 0;
737 }
738 
739 /**
740  * lsm_early_task - during initialization allocate a composite task blob
741  * @task: the task that needs a blob
742  *
743  * Allocate the task blob for all the modules
744  */
745 static void __init lsm_early_task(struct task_struct *task)
746 {
747 	int rc = lsm_task_alloc(task);
748 
749 	if (rc)
750 		panic("%s: Early task alloc failed.\n", __func__);
751 }
752 
753 /**
754  * lsm_superblock_alloc - allocate a composite superblock blob
755  * @sb: the superblock that needs a blob
756  *
757  * Allocate the superblock blob for all the modules
758  *
759  * Returns 0, or -ENOMEM if memory can't be allocated.
760  */
761 static int lsm_superblock_alloc(struct super_block *sb)
762 {
763 	if (blob_sizes.lbs_superblock == 0) {
764 		sb->s_security = NULL;
765 		return 0;
766 	}
767 
768 	sb->s_security = kzalloc(blob_sizes.lbs_superblock, GFP_KERNEL);
769 	if (sb->s_security == NULL)
770 		return -ENOMEM;
771 	return 0;
772 }
773 
774 /**
775  * lsm_fill_user_ctx - Fill a user space lsm_ctx structure
776  * @uctx: a userspace LSM context to be filled
777  * @uctx_len: available uctx size (input), used uctx size (output)
778  * @val: the new LSM context value
779  * @val_len: the size of the new LSM context value
780  * @id: LSM id
781  * @flags: LSM defined flags
782  *
783  * Fill all of the fields in a userspace lsm_ctx structure.
784  *
785  * Returns 0 on success, -E2BIG if userspace buffer is not large enough,
786  * -EFAULT on a copyout error, -ENOMEM if memory can't be allocated.
787  */
788 int lsm_fill_user_ctx(struct lsm_ctx __user *uctx, size_t *uctx_len,
789 		      void *val, size_t val_len,
790 		      u64 id, u64 flags)
791 {
792 	struct lsm_ctx *nctx = NULL;
793 	size_t nctx_len;
794 	int rc = 0;
795 
796 	nctx_len = ALIGN(struct_size(nctx, ctx, val_len), sizeof(void *));
797 	if (nctx_len > *uctx_len) {
798 		rc = -E2BIG;
799 		goto out;
800 	}
801 
802 	nctx = kzalloc(nctx_len, GFP_KERNEL);
803 	if (nctx == NULL) {
804 		rc = -ENOMEM;
805 		goto out;
806 	}
807 	nctx->id = id;
808 	nctx->flags = flags;
809 	nctx->len = nctx_len;
810 	nctx->ctx_len = val_len;
811 	memcpy(nctx->ctx, val, val_len);
812 
813 	if (copy_to_user(uctx, nctx, nctx_len))
814 		rc = -EFAULT;
815 
816 out:
817 	kfree(nctx);
818 	*uctx_len = nctx_len;
819 	return rc;
820 }
821 
822 /*
823  * The default value of the LSM hook is defined in linux/lsm_hook_defs.h and
824  * can be accessed with:
825  *
826  *	LSM_RET_DEFAULT(<hook_name>)
827  *
828  * The macros below define static constants for the default value of each
829  * LSM hook.
830  */
831 #define LSM_RET_DEFAULT(NAME) (NAME##_default)
832 #define DECLARE_LSM_RET_DEFAULT_void(DEFAULT, NAME)
833 #define DECLARE_LSM_RET_DEFAULT_int(DEFAULT, NAME) \
834 	static const int __maybe_unused LSM_RET_DEFAULT(NAME) = (DEFAULT);
835 #define LSM_HOOK(RET, DEFAULT, NAME, ...) \
836 	DECLARE_LSM_RET_DEFAULT_##RET(DEFAULT, NAME)
837 
838 #include <linux/lsm_hook_defs.h>
839 #undef LSM_HOOK
840 
841 /*
842  * Hook list operation macros.
843  *
844  * call_void_hook:
845  *	This is a hook that does not return a value.
846  *
847  * call_int_hook:
848  *	This is a hook that returns a value.
849  */
850 
851 #define call_void_hook(FUNC, ...)				\
852 	do {							\
853 		struct security_hook_list *P;			\
854 								\
855 		hlist_for_each_entry(P, &security_hook_heads.FUNC, list) \
856 			P->hook.FUNC(__VA_ARGS__);		\
857 	} while (0)
858 
859 #define call_int_hook(FUNC, IRC, ...) ({			\
860 	int RC = IRC;						\
861 	do {							\
862 		struct security_hook_list *P;			\
863 								\
864 		hlist_for_each_entry(P, &security_hook_heads.FUNC, list) { \
865 			RC = P->hook.FUNC(__VA_ARGS__);		\
866 			if (RC != 0)				\
867 				break;				\
868 		}						\
869 	} while (0);						\
870 	RC;							\
871 })
872 
873 /* Security operations */
874 
875 /**
876  * security_binder_set_context_mgr() - Check if becoming binder ctx mgr is ok
877  * @mgr: task credentials of current binder process
878  *
879  * Check whether @mgr is allowed to be the binder context manager.
880  *
881  * Return: Return 0 if permission is granted.
882  */
883 int security_binder_set_context_mgr(const struct cred *mgr)
884 {
885 	return call_int_hook(binder_set_context_mgr, 0, mgr);
886 }
887 
888 /**
889  * security_binder_transaction() - Check if a binder transaction is allowed
890  * @from: sending process
891  * @to: receiving process
892  *
893  * Check whether @from is allowed to invoke a binder transaction call to @to.
894  *
895  * Return: Returns 0 if permission is granted.
896  */
897 int security_binder_transaction(const struct cred *from,
898 				const struct cred *to)
899 {
900 	return call_int_hook(binder_transaction, 0, from, to);
901 }
902 
903 /**
904  * security_binder_transfer_binder() - Check if a binder transfer is allowed
905  * @from: sending process
906  * @to: receiving process
907  *
908  * Check whether @from is allowed to transfer a binder reference to @to.
909  *
910  * Return: Returns 0 if permission is granted.
911  */
912 int security_binder_transfer_binder(const struct cred *from,
913 				    const struct cred *to)
914 {
915 	return call_int_hook(binder_transfer_binder, 0, from, to);
916 }
917 
918 /**
919  * security_binder_transfer_file() - Check if a binder file xfer is allowed
920  * @from: sending process
921  * @to: receiving process
922  * @file: file being transferred
923  *
924  * Check whether @from is allowed to transfer @file to @to.
925  *
926  * Return: Returns 0 if permission is granted.
927  */
928 int security_binder_transfer_file(const struct cred *from,
929 				  const struct cred *to, const struct file *file)
930 {
931 	return call_int_hook(binder_transfer_file, 0, from, to, file);
932 }
933 
934 /**
935  * security_ptrace_access_check() - Check if tracing is allowed
936  * @child: target process
937  * @mode: PTRACE_MODE flags
938  *
939  * Check permission before allowing the current process to trace the @child
940  * process.  Security modules may also want to perform a process tracing check
941  * during an execve in the set_security or apply_creds hooks of tracing check
942  * during an execve in the bprm_set_creds hook of binprm_security_ops if the
943  * process is being traced and its security attributes would be changed by the
944  * execve.
945  *
946  * Return: Returns 0 if permission is granted.
947  */
948 int security_ptrace_access_check(struct task_struct *child, unsigned int mode)
949 {
950 	return call_int_hook(ptrace_access_check, 0, child, mode);
951 }
952 
953 /**
954  * security_ptrace_traceme() - Check if tracing is allowed
955  * @parent: tracing process
956  *
957  * Check that the @parent process has sufficient permission to trace the
958  * current process before allowing the current process to present itself to the
959  * @parent process for tracing.
960  *
961  * Return: Returns 0 if permission is granted.
962  */
963 int security_ptrace_traceme(struct task_struct *parent)
964 {
965 	return call_int_hook(ptrace_traceme, 0, parent);
966 }
967 
968 /**
969  * security_capget() - Get the capability sets for a process
970  * @target: target process
971  * @effective: effective capability set
972  * @inheritable: inheritable capability set
973  * @permitted: permitted capability set
974  *
975  * Get the @effective, @inheritable, and @permitted capability sets for the
976  * @target process.  The hook may also perform permission checking to determine
977  * if the current process is allowed to see the capability sets of the @target
978  * process.
979  *
980  * Return: Returns 0 if the capability sets were successfully obtained.
981  */
982 int security_capget(const struct task_struct *target,
983 		    kernel_cap_t *effective,
984 		    kernel_cap_t *inheritable,
985 		    kernel_cap_t *permitted)
986 {
987 	return call_int_hook(capget, 0, target,
988 			     effective, inheritable, permitted);
989 }
990 
991 /**
992  * security_capset() - Set the capability sets for a process
993  * @new: new credentials for the target process
994  * @old: current credentials of the target process
995  * @effective: effective capability set
996  * @inheritable: inheritable capability set
997  * @permitted: permitted capability set
998  *
999  * Set the @effective, @inheritable, and @permitted capability sets for the
1000  * current process.
1001  *
1002  * Return: Returns 0 and update @new if permission is granted.
1003  */
1004 int security_capset(struct cred *new, const struct cred *old,
1005 		    const kernel_cap_t *effective,
1006 		    const kernel_cap_t *inheritable,
1007 		    const kernel_cap_t *permitted)
1008 {
1009 	return call_int_hook(capset, 0, new, old,
1010 			     effective, inheritable, permitted);
1011 }
1012 
1013 /**
1014  * security_capable() - Check if a process has the necessary capability
1015  * @cred: credentials to examine
1016  * @ns: user namespace
1017  * @cap: capability requested
1018  * @opts: capability check options
1019  *
1020  * Check whether the @tsk process has the @cap capability in the indicated
1021  * credentials.  @cap contains the capability <include/linux/capability.h>.
1022  * @opts contains options for the capable check <include/linux/security.h>.
1023  *
1024  * Return: Returns 0 if the capability is granted.
1025  */
1026 int security_capable(const struct cred *cred,
1027 		     struct user_namespace *ns,
1028 		     int cap,
1029 		     unsigned int opts)
1030 {
1031 	return call_int_hook(capable, 0, cred, ns, cap, opts);
1032 }
1033 
1034 /**
1035  * security_quotactl() - Check if a quotactl() syscall is allowed for this fs
1036  * @cmds: commands
1037  * @type: type
1038  * @id: id
1039  * @sb: filesystem
1040  *
1041  * Check whether the quotactl syscall is allowed for this @sb.
1042  *
1043  * Return: Returns 0 if permission is granted.
1044  */
1045 int security_quotactl(int cmds, int type, int id, const struct super_block *sb)
1046 {
1047 	return call_int_hook(quotactl, 0, cmds, type, id, sb);
1048 }
1049 
1050 /**
1051  * security_quota_on() - Check if QUOTAON is allowed for a dentry
1052  * @dentry: dentry
1053  *
1054  * Check whether QUOTAON is allowed for @dentry.
1055  *
1056  * Return: Returns 0 if permission is granted.
1057  */
1058 int security_quota_on(struct dentry *dentry)
1059 {
1060 	return call_int_hook(quota_on, 0, dentry);
1061 }
1062 
1063 /**
1064  * security_syslog() - Check if accessing the kernel message ring is allowed
1065  * @type: SYSLOG_ACTION_* type
1066  *
1067  * Check permission before accessing the kernel message ring or changing
1068  * logging to the console.  See the syslog(2) manual page for an explanation of
1069  * the @type values.
1070  *
1071  * Return: Return 0 if permission is granted.
1072  */
1073 int security_syslog(int type)
1074 {
1075 	return call_int_hook(syslog, 0, type);
1076 }
1077 
1078 /**
1079  * security_settime64() - Check if changing the system time is allowed
1080  * @ts: new time
1081  * @tz: timezone
1082  *
1083  * Check permission to change the system time, struct timespec64 is defined in
1084  * <include/linux/time64.h> and timezone is defined in <include/linux/time.h>.
1085  *
1086  * Return: Returns 0 if permission is granted.
1087  */
1088 int security_settime64(const struct timespec64 *ts, const struct timezone *tz)
1089 {
1090 	return call_int_hook(settime, 0, ts, tz);
1091 }
1092 
1093 /**
1094  * security_vm_enough_memory_mm() - Check if allocating a new mem map is allowed
1095  * @mm: mm struct
1096  * @pages: number of pages
1097  *
1098  * Check permissions for allocating a new virtual mapping.  If all LSMs return
1099  * a positive value, __vm_enough_memory() will be called with cap_sys_admin
1100  * set. If at least one LSM returns 0 or negative, __vm_enough_memory() will be
1101  * called with cap_sys_admin cleared.
1102  *
1103  * Return: Returns 0 if permission is granted by the LSM infrastructure to the
1104  *         caller.
1105  */
1106 int security_vm_enough_memory_mm(struct mm_struct *mm, long pages)
1107 {
1108 	struct security_hook_list *hp;
1109 	int cap_sys_admin = 1;
1110 	int rc;
1111 
1112 	/*
1113 	 * The module will respond with a positive value if
1114 	 * it thinks the __vm_enough_memory() call should be
1115 	 * made with the cap_sys_admin set. If all of the modules
1116 	 * agree that it should be set it will. If any module
1117 	 * thinks it should not be set it won't.
1118 	 */
1119 	hlist_for_each_entry(hp, &security_hook_heads.vm_enough_memory, list) {
1120 		rc = hp->hook.vm_enough_memory(mm, pages);
1121 		if (rc <= 0) {
1122 			cap_sys_admin = 0;
1123 			break;
1124 		}
1125 	}
1126 	return __vm_enough_memory(mm, pages, cap_sys_admin);
1127 }
1128 
1129 /**
1130  * security_bprm_creds_for_exec() - Prepare the credentials for exec()
1131  * @bprm: binary program information
1132  *
1133  * If the setup in prepare_exec_creds did not setup @bprm->cred->security
1134  * properly for executing @bprm->file, update the LSM's portion of
1135  * @bprm->cred->security to be what commit_creds needs to install for the new
1136  * program.  This hook may also optionally check permissions (e.g. for
1137  * transitions between security domains).  The hook must set @bprm->secureexec
1138  * to 1 if AT_SECURE should be set to request libc enable secure mode.  @bprm
1139  * contains the linux_binprm structure.
1140  *
1141  * Return: Returns 0 if the hook is successful and permission is granted.
1142  */
1143 int security_bprm_creds_for_exec(struct linux_binprm *bprm)
1144 {
1145 	return call_int_hook(bprm_creds_for_exec, 0, bprm);
1146 }
1147 
1148 /**
1149  * security_bprm_creds_from_file() - Update linux_binprm creds based on file
1150  * @bprm: binary program information
1151  * @file: associated file
1152  *
1153  * If @file is setpcap, suid, sgid or otherwise marked to change privilege upon
1154  * exec, update @bprm->cred to reflect that change. This is called after
1155  * finding the binary that will be executed without an interpreter.  This
1156  * ensures that the credentials will not be derived from a script that the
1157  * binary will need to reopen, which when reopend may end up being a completely
1158  * different file.  This hook may also optionally check permissions (e.g. for
1159  * transitions between security domains).  The hook must set @bprm->secureexec
1160  * to 1 if AT_SECURE should be set to request libc enable secure mode.  The
1161  * hook must add to @bprm->per_clear any personality flags that should be
1162  * cleared from current->personality.  @bprm contains the linux_binprm
1163  * structure.
1164  *
1165  * Return: Returns 0 if the hook is successful and permission is granted.
1166  */
1167 int security_bprm_creds_from_file(struct linux_binprm *bprm, const struct file *file)
1168 {
1169 	return call_int_hook(bprm_creds_from_file, 0, bprm, file);
1170 }
1171 
1172 /**
1173  * security_bprm_check() - Mediate binary handler search
1174  * @bprm: binary program information
1175  *
1176  * This hook mediates the point when a search for a binary handler will begin.
1177  * It allows a check against the @bprm->cred->security value which was set in
1178  * the preceding creds_for_exec call.  The argv list and envp list are reliably
1179  * available in @bprm.  This hook may be called multiple times during a single
1180  * execve.  @bprm contains the linux_binprm structure.
1181  *
1182  * Return: Returns 0 if the hook is successful and permission is granted.
1183  */
1184 int security_bprm_check(struct linux_binprm *bprm)
1185 {
1186 	return call_int_hook(bprm_check_security, 0, bprm);
1187 }
1188 
1189 /**
1190  * security_bprm_committing_creds() - Install creds for a process during exec()
1191  * @bprm: binary program information
1192  *
1193  * Prepare to install the new security attributes of a process being
1194  * transformed by an execve operation, based on the old credentials pointed to
1195  * by @current->cred and the information set in @bprm->cred by the
1196  * bprm_creds_for_exec hook.  @bprm points to the linux_binprm structure.  This
1197  * hook is a good place to perform state changes on the process such as closing
1198  * open file descriptors to which access will no longer be granted when the
1199  * attributes are changed.  This is called immediately before commit_creds().
1200  */
1201 void security_bprm_committing_creds(const struct linux_binprm *bprm)
1202 {
1203 	call_void_hook(bprm_committing_creds, bprm);
1204 }
1205 
1206 /**
1207  * security_bprm_committed_creds() - Tidy up after cred install during exec()
1208  * @bprm: binary program information
1209  *
1210  * Tidy up after the installation of the new security attributes of a process
1211  * being transformed by an execve operation.  The new credentials have, by this
1212  * point, been set to @current->cred.  @bprm points to the linux_binprm
1213  * structure.  This hook is a good place to perform state changes on the
1214  * process such as clearing out non-inheritable signal state.  This is called
1215  * immediately after commit_creds().
1216  */
1217 void security_bprm_committed_creds(const struct linux_binprm *bprm)
1218 {
1219 	call_void_hook(bprm_committed_creds, bprm);
1220 }
1221 
1222 /**
1223  * security_fs_context_submount() - Initialise fc->security
1224  * @fc: new filesystem context
1225  * @reference: dentry reference for submount/remount
1226  *
1227  * Fill out the ->security field for a new fs_context.
1228  *
1229  * Return: Returns 0 on success or negative error code on failure.
1230  */
1231 int security_fs_context_submount(struct fs_context *fc, struct super_block *reference)
1232 {
1233 	return call_int_hook(fs_context_submount, 0, fc, reference);
1234 }
1235 
1236 /**
1237  * security_fs_context_dup() - Duplicate a fs_context LSM blob
1238  * @fc: destination filesystem context
1239  * @src_fc: source filesystem context
1240  *
1241  * Allocate and attach a security structure to sc->security.  This pointer is
1242  * initialised to NULL by the caller.  @fc indicates the new filesystem context.
1243  * @src_fc indicates the original filesystem context.
1244  *
1245  * Return: Returns 0 on success or a negative error code on failure.
1246  */
1247 int security_fs_context_dup(struct fs_context *fc, struct fs_context *src_fc)
1248 {
1249 	return call_int_hook(fs_context_dup, 0, fc, src_fc);
1250 }
1251 
1252 /**
1253  * security_fs_context_parse_param() - Configure a filesystem context
1254  * @fc: filesystem context
1255  * @param: filesystem parameter
1256  *
1257  * Userspace provided a parameter to configure a superblock.  The LSM can
1258  * consume the parameter or return it to the caller for use elsewhere.
1259  *
1260  * Return: If the parameter is used by the LSM it should return 0, if it is
1261  *         returned to the caller -ENOPARAM is returned, otherwise a negative
1262  *         error code is returned.
1263  */
1264 int security_fs_context_parse_param(struct fs_context *fc,
1265 				    struct fs_parameter *param)
1266 {
1267 	struct security_hook_list *hp;
1268 	int trc;
1269 	int rc = -ENOPARAM;
1270 
1271 	hlist_for_each_entry(hp, &security_hook_heads.fs_context_parse_param,
1272 			     list) {
1273 		trc = hp->hook.fs_context_parse_param(fc, param);
1274 		if (trc == 0)
1275 			rc = 0;
1276 		else if (trc != -ENOPARAM)
1277 			return trc;
1278 	}
1279 	return rc;
1280 }
1281 
1282 /**
1283  * security_sb_alloc() - Allocate a super_block LSM blob
1284  * @sb: filesystem superblock
1285  *
1286  * Allocate and attach a security structure to the sb->s_security field.  The
1287  * s_security field is initialized to NULL when the structure is allocated.
1288  * @sb contains the super_block structure to be modified.
1289  *
1290  * Return: Returns 0 if operation was successful.
1291  */
1292 int security_sb_alloc(struct super_block *sb)
1293 {
1294 	int rc = lsm_superblock_alloc(sb);
1295 
1296 	if (unlikely(rc))
1297 		return rc;
1298 	rc = call_int_hook(sb_alloc_security, 0, sb);
1299 	if (unlikely(rc))
1300 		security_sb_free(sb);
1301 	return rc;
1302 }
1303 
1304 /**
1305  * security_sb_delete() - Release super_block LSM associated objects
1306  * @sb: filesystem superblock
1307  *
1308  * Release objects tied to a superblock (e.g. inodes).  @sb contains the
1309  * super_block structure being released.
1310  */
1311 void security_sb_delete(struct super_block *sb)
1312 {
1313 	call_void_hook(sb_delete, sb);
1314 }
1315 
1316 /**
1317  * security_sb_free() - Free a super_block LSM blob
1318  * @sb: filesystem superblock
1319  *
1320  * Deallocate and clear the sb->s_security field.  @sb contains the super_block
1321  * structure to be modified.
1322  */
1323 void security_sb_free(struct super_block *sb)
1324 {
1325 	call_void_hook(sb_free_security, sb);
1326 	kfree(sb->s_security);
1327 	sb->s_security = NULL;
1328 }
1329 
1330 /**
1331  * security_free_mnt_opts() - Free memory associated with mount options
1332  * @mnt_opts: LSM processed mount options
1333  *
1334  * Free memory associated with @mnt_ops.
1335  */
1336 void security_free_mnt_opts(void **mnt_opts)
1337 {
1338 	if (!*mnt_opts)
1339 		return;
1340 	call_void_hook(sb_free_mnt_opts, *mnt_opts);
1341 	*mnt_opts = NULL;
1342 }
1343 EXPORT_SYMBOL(security_free_mnt_opts);
1344 
1345 /**
1346  * security_sb_eat_lsm_opts() - Consume LSM mount options
1347  * @options: mount options
1348  * @mnt_opts: LSM processed mount options
1349  *
1350  * Eat (scan @options) and save them in @mnt_opts.
1351  *
1352  * Return: Returns 0 on success, negative values on failure.
1353  */
1354 int security_sb_eat_lsm_opts(char *options, void **mnt_opts)
1355 {
1356 	return call_int_hook(sb_eat_lsm_opts, 0, options, mnt_opts);
1357 }
1358 EXPORT_SYMBOL(security_sb_eat_lsm_opts);
1359 
1360 /**
1361  * security_sb_mnt_opts_compat() - Check if new mount options are allowed
1362  * @sb: filesystem superblock
1363  * @mnt_opts: new mount options
1364  *
1365  * Determine if the new mount options in @mnt_opts are allowed given the
1366  * existing mounted filesystem at @sb.  @sb superblock being compared.
1367  *
1368  * Return: Returns 0 if options are compatible.
1369  */
1370 int security_sb_mnt_opts_compat(struct super_block *sb,
1371 				void *mnt_opts)
1372 {
1373 	return call_int_hook(sb_mnt_opts_compat, 0, sb, mnt_opts);
1374 }
1375 EXPORT_SYMBOL(security_sb_mnt_opts_compat);
1376 
1377 /**
1378  * security_sb_remount() - Verify no incompatible mount changes during remount
1379  * @sb: filesystem superblock
1380  * @mnt_opts: (re)mount options
1381  *
1382  * Extracts security system specific mount options and verifies no changes are
1383  * being made to those options.
1384  *
1385  * Return: Returns 0 if permission is granted.
1386  */
1387 int security_sb_remount(struct super_block *sb,
1388 			void *mnt_opts)
1389 {
1390 	return call_int_hook(sb_remount, 0, sb, mnt_opts);
1391 }
1392 EXPORT_SYMBOL(security_sb_remount);
1393 
1394 /**
1395  * security_sb_kern_mount() - Check if a kernel mount is allowed
1396  * @sb: filesystem superblock
1397  *
1398  * Mount this @sb if allowed by permissions.
1399  *
1400  * Return: Returns 0 if permission is granted.
1401  */
1402 int security_sb_kern_mount(const struct super_block *sb)
1403 {
1404 	return call_int_hook(sb_kern_mount, 0, sb);
1405 }
1406 
1407 /**
1408  * security_sb_show_options() - Output the mount options for a superblock
1409  * @m: output file
1410  * @sb: filesystem superblock
1411  *
1412  * Show (print on @m) mount options for this @sb.
1413  *
1414  * Return: Returns 0 on success, negative values on failure.
1415  */
1416 int security_sb_show_options(struct seq_file *m, struct super_block *sb)
1417 {
1418 	return call_int_hook(sb_show_options, 0, m, sb);
1419 }
1420 
1421 /**
1422  * security_sb_statfs() - Check if accessing fs stats is allowed
1423  * @dentry: superblock handle
1424  *
1425  * Check permission before obtaining filesystem statistics for the @mnt
1426  * mountpoint.  @dentry is a handle on the superblock for the filesystem.
1427  *
1428  * Return: Returns 0 if permission is granted.
1429  */
1430 int security_sb_statfs(struct dentry *dentry)
1431 {
1432 	return call_int_hook(sb_statfs, 0, dentry);
1433 }
1434 
1435 /**
1436  * security_sb_mount() - Check permission for mounting a filesystem
1437  * @dev_name: filesystem backing device
1438  * @path: mount point
1439  * @type: filesystem type
1440  * @flags: mount flags
1441  * @data: filesystem specific data
1442  *
1443  * Check permission before an object specified by @dev_name is mounted on the
1444  * mount point named by @nd.  For an ordinary mount, @dev_name identifies a
1445  * device if the file system type requires a device.  For a remount
1446  * (@flags & MS_REMOUNT), @dev_name is irrelevant.  For a loopback/bind mount
1447  * (@flags & MS_BIND), @dev_name identifies the	pathname of the object being
1448  * mounted.
1449  *
1450  * Return: Returns 0 if permission is granted.
1451  */
1452 int security_sb_mount(const char *dev_name, const struct path *path,
1453 		      const char *type, unsigned long flags, void *data)
1454 {
1455 	return call_int_hook(sb_mount, 0, dev_name, path, type, flags, data);
1456 }
1457 
1458 /**
1459  * security_sb_umount() - Check permission for unmounting a filesystem
1460  * @mnt: mounted filesystem
1461  * @flags: unmount flags
1462  *
1463  * Check permission before the @mnt file system is unmounted.
1464  *
1465  * Return: Returns 0 if permission is granted.
1466  */
1467 int security_sb_umount(struct vfsmount *mnt, int flags)
1468 {
1469 	return call_int_hook(sb_umount, 0, mnt, flags);
1470 }
1471 
1472 /**
1473  * security_sb_pivotroot() - Check permissions for pivoting the rootfs
1474  * @old_path: new location for current rootfs
1475  * @new_path: location of the new rootfs
1476  *
1477  * Check permission before pivoting the root filesystem.
1478  *
1479  * Return: Returns 0 if permission is granted.
1480  */
1481 int security_sb_pivotroot(const struct path *old_path,
1482 			  const struct path *new_path)
1483 {
1484 	return call_int_hook(sb_pivotroot, 0, old_path, new_path);
1485 }
1486 
1487 /**
1488  * security_sb_set_mnt_opts() - Set the mount options for a filesystem
1489  * @sb: filesystem superblock
1490  * @mnt_opts: binary mount options
1491  * @kern_flags: kernel flags (in)
1492  * @set_kern_flags: kernel flags (out)
1493  *
1494  * Set the security relevant mount options used for a superblock.
1495  *
1496  * Return: Returns 0 on success, error on failure.
1497  */
1498 int security_sb_set_mnt_opts(struct super_block *sb,
1499 			     void *mnt_opts,
1500 			     unsigned long kern_flags,
1501 			     unsigned long *set_kern_flags)
1502 {
1503 	return call_int_hook(sb_set_mnt_opts,
1504 			     mnt_opts ? -EOPNOTSUPP : 0, sb,
1505 			     mnt_opts, kern_flags, set_kern_flags);
1506 }
1507 EXPORT_SYMBOL(security_sb_set_mnt_opts);
1508 
1509 /**
1510  * security_sb_clone_mnt_opts() - Duplicate superblock mount options
1511  * @oldsb: source superblock
1512  * @newsb: destination superblock
1513  * @kern_flags: kernel flags (in)
1514  * @set_kern_flags: kernel flags (out)
1515  *
1516  * Copy all security options from a given superblock to another.
1517  *
1518  * Return: Returns 0 on success, error on failure.
1519  */
1520 int security_sb_clone_mnt_opts(const struct super_block *oldsb,
1521 			       struct super_block *newsb,
1522 			       unsigned long kern_flags,
1523 			       unsigned long *set_kern_flags)
1524 {
1525 	return call_int_hook(sb_clone_mnt_opts, 0, oldsb, newsb,
1526 			     kern_flags, set_kern_flags);
1527 }
1528 EXPORT_SYMBOL(security_sb_clone_mnt_opts);
1529 
1530 /**
1531  * security_move_mount() - Check permissions for moving a mount
1532  * @from_path: source mount point
1533  * @to_path: destination mount point
1534  *
1535  * Check permission before a mount is moved.
1536  *
1537  * Return: Returns 0 if permission is granted.
1538  */
1539 int security_move_mount(const struct path *from_path,
1540 			const struct path *to_path)
1541 {
1542 	return call_int_hook(move_mount, 0, from_path, to_path);
1543 }
1544 
1545 /**
1546  * security_path_notify() - Check if setting a watch is allowed
1547  * @path: file path
1548  * @mask: event mask
1549  * @obj_type: file path type
1550  *
1551  * Check permissions before setting a watch on events as defined by @mask, on
1552  * an object at @path, whose type is defined by @obj_type.
1553  *
1554  * Return: Returns 0 if permission is granted.
1555  */
1556 int security_path_notify(const struct path *path, u64 mask,
1557 			 unsigned int obj_type)
1558 {
1559 	return call_int_hook(path_notify, 0, path, mask, obj_type);
1560 }
1561 
1562 /**
1563  * security_inode_alloc() - Allocate an inode LSM blob
1564  * @inode: the inode
1565  *
1566  * Allocate and attach a security structure to @inode->i_security.  The
1567  * i_security field is initialized to NULL when the inode structure is
1568  * allocated.
1569  *
1570  * Return: Return 0 if operation was successful.
1571  */
1572 int security_inode_alloc(struct inode *inode)
1573 {
1574 	int rc = lsm_inode_alloc(inode);
1575 
1576 	if (unlikely(rc))
1577 		return rc;
1578 	rc = call_int_hook(inode_alloc_security, 0, inode);
1579 	if (unlikely(rc))
1580 		security_inode_free(inode);
1581 	return rc;
1582 }
1583 
1584 static void inode_free_by_rcu(struct rcu_head *head)
1585 {
1586 	/*
1587 	 * The rcu head is at the start of the inode blob
1588 	 */
1589 	kmem_cache_free(lsm_inode_cache, head);
1590 }
1591 
1592 /**
1593  * security_inode_free() - Free an inode's LSM blob
1594  * @inode: the inode
1595  *
1596  * Deallocate the inode security structure and set @inode->i_security to NULL.
1597  */
1598 void security_inode_free(struct inode *inode)
1599 {
1600 	integrity_inode_free(inode);
1601 	call_void_hook(inode_free_security, inode);
1602 	/*
1603 	 * The inode may still be referenced in a path walk and
1604 	 * a call to security_inode_permission() can be made
1605 	 * after inode_free_security() is called. Ideally, the VFS
1606 	 * wouldn't do this, but fixing that is a much harder
1607 	 * job. For now, simply free the i_security via RCU, and
1608 	 * leave the current inode->i_security pointer intact.
1609 	 * The inode will be freed after the RCU grace period too.
1610 	 */
1611 	if (inode->i_security)
1612 		call_rcu((struct rcu_head *)inode->i_security,
1613 			 inode_free_by_rcu);
1614 }
1615 
1616 /**
1617  * security_dentry_init_security() - Perform dentry initialization
1618  * @dentry: the dentry to initialize
1619  * @mode: mode used to determine resource type
1620  * @name: name of the last path component
1621  * @xattr_name: name of the security/LSM xattr
1622  * @ctx: pointer to the resulting LSM context
1623  * @ctxlen: length of @ctx
1624  *
1625  * Compute a context for a dentry as the inode is not yet available since NFSv4
1626  * has no label backed by an EA anyway.  It is important to note that
1627  * @xattr_name does not need to be free'd by the caller, it is a static string.
1628  *
1629  * Return: Returns 0 on success, negative values on failure.
1630  */
1631 int security_dentry_init_security(struct dentry *dentry, int mode,
1632 				  const struct qstr *name,
1633 				  const char **xattr_name, void **ctx,
1634 				  u32 *ctxlen)
1635 {
1636 	struct security_hook_list *hp;
1637 	int rc;
1638 
1639 	/*
1640 	 * Only one module will provide a security context.
1641 	 */
1642 	hlist_for_each_entry(hp, &security_hook_heads.dentry_init_security,
1643 			     list) {
1644 		rc = hp->hook.dentry_init_security(dentry, mode, name,
1645 						   xattr_name, ctx, ctxlen);
1646 		if (rc != LSM_RET_DEFAULT(dentry_init_security))
1647 			return rc;
1648 	}
1649 	return LSM_RET_DEFAULT(dentry_init_security);
1650 }
1651 EXPORT_SYMBOL(security_dentry_init_security);
1652 
1653 /**
1654  * security_dentry_create_files_as() - Perform dentry initialization
1655  * @dentry: the dentry to initialize
1656  * @mode: mode used to determine resource type
1657  * @name: name of the last path component
1658  * @old: creds to use for LSM context calculations
1659  * @new: creds to modify
1660  *
1661  * Compute a context for a dentry as the inode is not yet available and set
1662  * that context in passed in creds so that new files are created using that
1663  * context. Context is calculated using the passed in creds and not the creds
1664  * of the caller.
1665  *
1666  * Return: Returns 0 on success, error on failure.
1667  */
1668 int security_dentry_create_files_as(struct dentry *dentry, int mode,
1669 				    struct qstr *name,
1670 				    const struct cred *old, struct cred *new)
1671 {
1672 	return call_int_hook(dentry_create_files_as, 0, dentry, mode,
1673 			     name, old, new);
1674 }
1675 EXPORT_SYMBOL(security_dentry_create_files_as);
1676 
1677 /**
1678  * security_inode_init_security() - Initialize an inode's LSM context
1679  * @inode: the inode
1680  * @dir: parent directory
1681  * @qstr: last component of the pathname
1682  * @initxattrs: callback function to write xattrs
1683  * @fs_data: filesystem specific data
1684  *
1685  * Obtain the security attribute name suffix and value to set on a newly
1686  * created inode and set up the incore security field for the new inode.  This
1687  * hook is called by the fs code as part of the inode creation transaction and
1688  * provides for atomic labeling of the inode, unlike the post_create/mkdir/...
1689  * hooks called by the VFS.
1690  *
1691  * The hook function is expected to populate the xattrs array, by calling
1692  * lsm_get_xattr_slot() to retrieve the slots reserved by the security module
1693  * with the lbs_xattr_count field of the lsm_blob_sizes structure.  For each
1694  * slot, the hook function should set ->name to the attribute name suffix
1695  * (e.g. selinux), to allocate ->value (will be freed by the caller) and set it
1696  * to the attribute value, to set ->value_len to the length of the value.  If
1697  * the security module does not use security attributes or does not wish to put
1698  * a security attribute on this particular inode, then it should return
1699  * -EOPNOTSUPP to skip this processing.
1700  *
1701  * Return: Returns 0 if the LSM successfully initialized all of the inode
1702  *         security attributes that are required, negative values otherwise.
1703  */
1704 int security_inode_init_security(struct inode *inode, struct inode *dir,
1705 				 const struct qstr *qstr,
1706 				 const initxattrs initxattrs, void *fs_data)
1707 {
1708 	struct security_hook_list *hp;
1709 	struct xattr *new_xattrs = NULL;
1710 	int ret = -EOPNOTSUPP, xattr_count = 0;
1711 
1712 	if (unlikely(IS_PRIVATE(inode)))
1713 		return 0;
1714 
1715 	if (!blob_sizes.lbs_xattr_count)
1716 		return 0;
1717 
1718 	if (initxattrs) {
1719 		/* Allocate +1 for EVM and +1 as terminator. */
1720 		new_xattrs = kcalloc(blob_sizes.lbs_xattr_count + 2,
1721 				     sizeof(*new_xattrs), GFP_NOFS);
1722 		if (!new_xattrs)
1723 			return -ENOMEM;
1724 	}
1725 
1726 	hlist_for_each_entry(hp, &security_hook_heads.inode_init_security,
1727 			     list) {
1728 		ret = hp->hook.inode_init_security(inode, dir, qstr, new_xattrs,
1729 						  &xattr_count);
1730 		if (ret && ret != -EOPNOTSUPP)
1731 			goto out;
1732 		/*
1733 		 * As documented in lsm_hooks.h, -EOPNOTSUPP in this context
1734 		 * means that the LSM is not willing to provide an xattr, not
1735 		 * that it wants to signal an error. Thus, continue to invoke
1736 		 * the remaining LSMs.
1737 		 */
1738 	}
1739 
1740 	/* If initxattrs() is NULL, xattr_count is zero, skip the call. */
1741 	if (!xattr_count)
1742 		goto out;
1743 
1744 	ret = initxattrs(inode, new_xattrs, fs_data);
1745 out:
1746 	for (; xattr_count > 0; xattr_count--)
1747 		kfree(new_xattrs[xattr_count - 1].value);
1748 	kfree(new_xattrs);
1749 	return (ret == -EOPNOTSUPP) ? 0 : ret;
1750 }
1751 EXPORT_SYMBOL(security_inode_init_security);
1752 
1753 /**
1754  * security_inode_init_security_anon() - Initialize an anonymous inode
1755  * @inode: the inode
1756  * @name: the anonymous inode class
1757  * @context_inode: an optional related inode
1758  *
1759  * Set up the incore security field for the new anonymous inode and return
1760  * whether the inode creation is permitted by the security module or not.
1761  *
1762  * Return: Returns 0 on success, -EACCES if the security module denies the
1763  * creation of this inode, or another -errno upon other errors.
1764  */
1765 int security_inode_init_security_anon(struct inode *inode,
1766 				      const struct qstr *name,
1767 				      const struct inode *context_inode)
1768 {
1769 	return call_int_hook(inode_init_security_anon, 0, inode, name,
1770 			     context_inode);
1771 }
1772 
1773 #ifdef CONFIG_SECURITY_PATH
1774 /**
1775  * security_path_mknod() - Check if creating a special file is allowed
1776  * @dir: parent directory
1777  * @dentry: new file
1778  * @mode: new file mode
1779  * @dev: device number
1780  *
1781  * Check permissions when creating a file. Note that this hook is called even
1782  * if mknod operation is being done for a regular file.
1783  *
1784  * Return: Returns 0 if permission is granted.
1785  */
1786 int security_path_mknod(const struct path *dir, struct dentry *dentry,
1787 			umode_t mode, unsigned int dev)
1788 {
1789 	if (unlikely(IS_PRIVATE(d_backing_inode(dir->dentry))))
1790 		return 0;
1791 	return call_int_hook(path_mknod, 0, dir, dentry, mode, dev);
1792 }
1793 EXPORT_SYMBOL(security_path_mknod);
1794 
1795 /**
1796  * security_path_post_mknod() - Update inode security field after file creation
1797  * @idmap: idmap of the mount
1798  * @dentry: new file
1799  *
1800  * Update inode security field after a file has been created.
1801  */
1802 void security_path_post_mknod(struct mnt_idmap *idmap, struct dentry *dentry)
1803 {
1804 	if (unlikely(IS_PRIVATE(d_backing_inode(dentry))))
1805 		return;
1806 	call_void_hook(path_post_mknod, idmap, dentry);
1807 }
1808 
1809 /**
1810  * security_path_mkdir() - Check if creating a new directory is allowed
1811  * @dir: parent directory
1812  * @dentry: new directory
1813  * @mode: new directory mode
1814  *
1815  * Check permissions to create a new directory in the existing directory.
1816  *
1817  * Return: Returns 0 if permission is granted.
1818  */
1819 int security_path_mkdir(const struct path *dir, struct dentry *dentry,
1820 			umode_t mode)
1821 {
1822 	if (unlikely(IS_PRIVATE(d_backing_inode(dir->dentry))))
1823 		return 0;
1824 	return call_int_hook(path_mkdir, 0, dir, dentry, mode);
1825 }
1826 EXPORT_SYMBOL(security_path_mkdir);
1827 
1828 /**
1829  * security_path_rmdir() - Check if removing a directory is allowed
1830  * @dir: parent directory
1831  * @dentry: directory to remove
1832  *
1833  * Check the permission to remove a directory.
1834  *
1835  * Return: Returns 0 if permission is granted.
1836  */
1837 int security_path_rmdir(const struct path *dir, struct dentry *dentry)
1838 {
1839 	if (unlikely(IS_PRIVATE(d_backing_inode(dir->dentry))))
1840 		return 0;
1841 	return call_int_hook(path_rmdir, 0, dir, dentry);
1842 }
1843 
1844 /**
1845  * security_path_unlink() - Check if removing a hard link is allowed
1846  * @dir: parent directory
1847  * @dentry: file
1848  *
1849  * Check the permission to remove a hard link to a file.
1850  *
1851  * Return: Returns 0 if permission is granted.
1852  */
1853 int security_path_unlink(const struct path *dir, struct dentry *dentry)
1854 {
1855 	if (unlikely(IS_PRIVATE(d_backing_inode(dir->dentry))))
1856 		return 0;
1857 	return call_int_hook(path_unlink, 0, dir, dentry);
1858 }
1859 EXPORT_SYMBOL(security_path_unlink);
1860 
1861 /**
1862  * security_path_symlink() - Check if creating a symbolic link is allowed
1863  * @dir: parent directory
1864  * @dentry: symbolic link
1865  * @old_name: file pathname
1866  *
1867  * Check the permission to create a symbolic link to a file.
1868  *
1869  * Return: Returns 0 if permission is granted.
1870  */
1871 int security_path_symlink(const struct path *dir, struct dentry *dentry,
1872 			  const char *old_name)
1873 {
1874 	if (unlikely(IS_PRIVATE(d_backing_inode(dir->dentry))))
1875 		return 0;
1876 	return call_int_hook(path_symlink, 0, dir, dentry, old_name);
1877 }
1878 
1879 /**
1880  * security_path_link - Check if creating a hard link is allowed
1881  * @old_dentry: existing file
1882  * @new_dir: new parent directory
1883  * @new_dentry: new link
1884  *
1885  * Check permission before creating a new hard link to a file.
1886  *
1887  * Return: Returns 0 if permission is granted.
1888  */
1889 int security_path_link(struct dentry *old_dentry, const struct path *new_dir,
1890 		       struct dentry *new_dentry)
1891 {
1892 	if (unlikely(IS_PRIVATE(d_backing_inode(old_dentry))))
1893 		return 0;
1894 	return call_int_hook(path_link, 0, old_dentry, new_dir, new_dentry);
1895 }
1896 
1897 /**
1898  * security_path_rename() - Check if renaming a file is allowed
1899  * @old_dir: parent directory of the old file
1900  * @old_dentry: the old file
1901  * @new_dir: parent directory of the new file
1902  * @new_dentry: the new file
1903  * @flags: flags
1904  *
1905  * Check for permission to rename a file or directory.
1906  *
1907  * Return: Returns 0 if permission is granted.
1908  */
1909 int security_path_rename(const struct path *old_dir, struct dentry *old_dentry,
1910 			 const struct path *new_dir, struct dentry *new_dentry,
1911 			 unsigned int flags)
1912 {
1913 	if (unlikely(IS_PRIVATE(d_backing_inode(old_dentry)) ||
1914 		     (d_is_positive(new_dentry) &&
1915 		      IS_PRIVATE(d_backing_inode(new_dentry)))))
1916 		return 0;
1917 
1918 	return call_int_hook(path_rename, 0, old_dir, old_dentry, new_dir,
1919 			     new_dentry, flags);
1920 }
1921 EXPORT_SYMBOL(security_path_rename);
1922 
1923 /**
1924  * security_path_truncate() - Check if truncating a file is allowed
1925  * @path: file
1926  *
1927  * Check permission before truncating the file indicated by path.  Note that
1928  * truncation permissions may also be checked based on already opened files,
1929  * using the security_file_truncate() hook.
1930  *
1931  * Return: Returns 0 if permission is granted.
1932  */
1933 int security_path_truncate(const struct path *path)
1934 {
1935 	if (unlikely(IS_PRIVATE(d_backing_inode(path->dentry))))
1936 		return 0;
1937 	return call_int_hook(path_truncate, 0, path);
1938 }
1939 
1940 /**
1941  * security_path_chmod() - Check if changing the file's mode is allowed
1942  * @path: file
1943  * @mode: new mode
1944  *
1945  * Check for permission to change a mode of the file @path. The new mode is
1946  * specified in @mode which is a bitmask of constants from
1947  * <include/uapi/linux/stat.h>.
1948  *
1949  * Return: Returns 0 if permission is granted.
1950  */
1951 int security_path_chmod(const struct path *path, umode_t mode)
1952 {
1953 	if (unlikely(IS_PRIVATE(d_backing_inode(path->dentry))))
1954 		return 0;
1955 	return call_int_hook(path_chmod, 0, path, mode);
1956 }
1957 
1958 /**
1959  * security_path_chown() - Check if changing the file's owner/group is allowed
1960  * @path: file
1961  * @uid: file owner
1962  * @gid: file group
1963  *
1964  * Check for permission to change owner/group of a file or directory.
1965  *
1966  * Return: Returns 0 if permission is granted.
1967  */
1968 int security_path_chown(const struct path *path, kuid_t uid, kgid_t gid)
1969 {
1970 	if (unlikely(IS_PRIVATE(d_backing_inode(path->dentry))))
1971 		return 0;
1972 	return call_int_hook(path_chown, 0, path, uid, gid);
1973 }
1974 
1975 /**
1976  * security_path_chroot() - Check if changing the root directory is allowed
1977  * @path: directory
1978  *
1979  * Check for permission to change root directory.
1980  *
1981  * Return: Returns 0 if permission is granted.
1982  */
1983 int security_path_chroot(const struct path *path)
1984 {
1985 	return call_int_hook(path_chroot, 0, path);
1986 }
1987 #endif /* CONFIG_SECURITY_PATH */
1988 
1989 /**
1990  * security_inode_create() - Check if creating a file is allowed
1991  * @dir: the parent directory
1992  * @dentry: the file being created
1993  * @mode: requested file mode
1994  *
1995  * Check permission to create a regular file.
1996  *
1997  * Return: Returns 0 if permission is granted.
1998  */
1999 int security_inode_create(struct inode *dir, struct dentry *dentry,
2000 			  umode_t mode)
2001 {
2002 	if (unlikely(IS_PRIVATE(dir)))
2003 		return 0;
2004 	return call_int_hook(inode_create, 0, dir, dentry, mode);
2005 }
2006 EXPORT_SYMBOL_GPL(security_inode_create);
2007 
2008 /**
2009  * security_inode_post_create_tmpfile() - Update inode security of new tmpfile
2010  * @idmap: idmap of the mount
2011  * @inode: inode of the new tmpfile
2012  *
2013  * Update inode security data after a tmpfile has been created.
2014  */
2015 void security_inode_post_create_tmpfile(struct mnt_idmap *idmap,
2016 					struct inode *inode)
2017 {
2018 	if (unlikely(IS_PRIVATE(inode)))
2019 		return;
2020 	call_void_hook(inode_post_create_tmpfile, idmap, inode);
2021 }
2022 
2023 /**
2024  * security_inode_link() - Check if creating a hard link is allowed
2025  * @old_dentry: existing file
2026  * @dir: new parent directory
2027  * @new_dentry: new link
2028  *
2029  * Check permission before creating a new hard link to a file.
2030  *
2031  * Return: Returns 0 if permission is granted.
2032  */
2033 int security_inode_link(struct dentry *old_dentry, struct inode *dir,
2034 			struct dentry *new_dentry)
2035 {
2036 	if (unlikely(IS_PRIVATE(d_backing_inode(old_dentry))))
2037 		return 0;
2038 	return call_int_hook(inode_link, 0, old_dentry, dir, new_dentry);
2039 }
2040 
2041 /**
2042  * security_inode_unlink() - Check if removing a hard link is allowed
2043  * @dir: parent directory
2044  * @dentry: file
2045  *
2046  * Check the permission to remove a hard link to a file.
2047  *
2048  * Return: Returns 0 if permission is granted.
2049  */
2050 int security_inode_unlink(struct inode *dir, struct dentry *dentry)
2051 {
2052 	if (unlikely(IS_PRIVATE(d_backing_inode(dentry))))
2053 		return 0;
2054 	return call_int_hook(inode_unlink, 0, dir, dentry);
2055 }
2056 
2057 /**
2058  * security_inode_symlink() - Check if creating a symbolic link is allowed
2059  * @dir: parent directory
2060  * @dentry: symbolic link
2061  * @old_name: existing filename
2062  *
2063  * Check the permission to create a symbolic link to a file.
2064  *
2065  * Return: Returns 0 if permission is granted.
2066  */
2067 int security_inode_symlink(struct inode *dir, struct dentry *dentry,
2068 			   const char *old_name)
2069 {
2070 	if (unlikely(IS_PRIVATE(dir)))
2071 		return 0;
2072 	return call_int_hook(inode_symlink, 0, dir, dentry, old_name);
2073 }
2074 
2075 /**
2076  * security_inode_mkdir() - Check if creation a new director is allowed
2077  * @dir: parent directory
2078  * @dentry: new directory
2079  * @mode: new directory mode
2080  *
2081  * Check permissions to create a new directory in the existing directory
2082  * associated with inode structure @dir.
2083  *
2084  * Return: Returns 0 if permission is granted.
2085  */
2086 int security_inode_mkdir(struct inode *dir, struct dentry *dentry, umode_t mode)
2087 {
2088 	if (unlikely(IS_PRIVATE(dir)))
2089 		return 0;
2090 	return call_int_hook(inode_mkdir, 0, dir, dentry, mode);
2091 }
2092 EXPORT_SYMBOL_GPL(security_inode_mkdir);
2093 
2094 /**
2095  * security_inode_rmdir() - Check if removing a directory is allowed
2096  * @dir: parent directory
2097  * @dentry: directory to be removed
2098  *
2099  * Check the permission to remove a directory.
2100  *
2101  * Return: Returns 0 if permission is granted.
2102  */
2103 int security_inode_rmdir(struct inode *dir, struct dentry *dentry)
2104 {
2105 	if (unlikely(IS_PRIVATE(d_backing_inode(dentry))))
2106 		return 0;
2107 	return call_int_hook(inode_rmdir, 0, dir, dentry);
2108 }
2109 
2110 /**
2111  * security_inode_mknod() - Check if creating a special file is allowed
2112  * @dir: parent directory
2113  * @dentry: new file
2114  * @mode: new file mode
2115  * @dev: device number
2116  *
2117  * Check permissions when creating a special file (or a socket or a fifo file
2118  * created via the mknod system call).  Note that if mknod operation is being
2119  * done for a regular file, then the create hook will be called and not this
2120  * hook.
2121  *
2122  * Return: Returns 0 if permission is granted.
2123  */
2124 int security_inode_mknod(struct inode *dir, struct dentry *dentry,
2125 			 umode_t mode, dev_t dev)
2126 {
2127 	if (unlikely(IS_PRIVATE(dir)))
2128 		return 0;
2129 	return call_int_hook(inode_mknod, 0, dir, dentry, mode, dev);
2130 }
2131 
2132 /**
2133  * security_inode_rename() - Check if renaming a file is allowed
2134  * @old_dir: parent directory of the old file
2135  * @old_dentry: the old file
2136  * @new_dir: parent directory of the new file
2137  * @new_dentry: the new file
2138  * @flags: flags
2139  *
2140  * Check for permission to rename a file or directory.
2141  *
2142  * Return: Returns 0 if permission is granted.
2143  */
2144 int security_inode_rename(struct inode *old_dir, struct dentry *old_dentry,
2145 			  struct inode *new_dir, struct dentry *new_dentry,
2146 			  unsigned int flags)
2147 {
2148 	if (unlikely(IS_PRIVATE(d_backing_inode(old_dentry)) ||
2149 		     (d_is_positive(new_dentry) &&
2150 		      IS_PRIVATE(d_backing_inode(new_dentry)))))
2151 		return 0;
2152 
2153 	if (flags & RENAME_EXCHANGE) {
2154 		int err = call_int_hook(inode_rename, 0, new_dir, new_dentry,
2155 					old_dir, old_dentry);
2156 		if (err)
2157 			return err;
2158 	}
2159 
2160 	return call_int_hook(inode_rename, 0, old_dir, old_dentry,
2161 			     new_dir, new_dentry);
2162 }
2163 
2164 /**
2165  * security_inode_readlink() - Check if reading a symbolic link is allowed
2166  * @dentry: link
2167  *
2168  * Check the permission to read the symbolic link.
2169  *
2170  * Return: Returns 0 if permission is granted.
2171  */
2172 int security_inode_readlink(struct dentry *dentry)
2173 {
2174 	if (unlikely(IS_PRIVATE(d_backing_inode(dentry))))
2175 		return 0;
2176 	return call_int_hook(inode_readlink, 0, dentry);
2177 }
2178 
2179 /**
2180  * security_inode_follow_link() - Check if following a symbolic link is allowed
2181  * @dentry: link dentry
2182  * @inode: link inode
2183  * @rcu: true if in RCU-walk mode
2184  *
2185  * Check permission to follow a symbolic link when looking up a pathname.  If
2186  * @rcu is true, @inode is not stable.
2187  *
2188  * Return: Returns 0 if permission is granted.
2189  */
2190 int security_inode_follow_link(struct dentry *dentry, struct inode *inode,
2191 			       bool rcu)
2192 {
2193 	if (unlikely(IS_PRIVATE(inode)))
2194 		return 0;
2195 	return call_int_hook(inode_follow_link, 0, dentry, inode, rcu);
2196 }
2197 
2198 /**
2199  * security_inode_permission() - Check if accessing an inode is allowed
2200  * @inode: inode
2201  * @mask: access mask
2202  *
2203  * Check permission before accessing an inode.  This hook is called by the
2204  * existing Linux permission function, so a security module can use it to
2205  * provide additional checking for existing Linux permission checks.  Notice
2206  * that this hook is called when a file is opened (as well as many other
2207  * operations), whereas the file_security_ops permission hook is called when
2208  * the actual read/write operations are performed.
2209  *
2210  * Return: Returns 0 if permission is granted.
2211  */
2212 int security_inode_permission(struct inode *inode, int mask)
2213 {
2214 	if (unlikely(IS_PRIVATE(inode)))
2215 		return 0;
2216 	return call_int_hook(inode_permission, 0, inode, mask);
2217 }
2218 
2219 /**
2220  * security_inode_setattr() - Check if setting file attributes is allowed
2221  * @idmap: idmap of the mount
2222  * @dentry: file
2223  * @attr: new attributes
2224  *
2225  * Check permission before setting file attributes.  Note that the kernel call
2226  * to notify_change is performed from several locations, whenever file
2227  * attributes change (such as when a file is truncated, chown/chmod operations,
2228  * transferring disk quotas, etc).
2229  *
2230  * Return: Returns 0 if permission is granted.
2231  */
2232 int security_inode_setattr(struct mnt_idmap *idmap,
2233 			   struct dentry *dentry, struct iattr *attr)
2234 {
2235 	if (unlikely(IS_PRIVATE(d_backing_inode(dentry))))
2236 		return 0;
2237 	return call_int_hook(inode_setattr, 0, idmap, dentry, attr);
2238 }
2239 EXPORT_SYMBOL_GPL(security_inode_setattr);
2240 
2241 /**
2242  * security_inode_post_setattr() - Update the inode after a setattr operation
2243  * @idmap: idmap of the mount
2244  * @dentry: file
2245  * @ia_valid: file attributes set
2246  *
2247  * Update inode security field after successful setting file attributes.
2248  */
2249 void security_inode_post_setattr(struct mnt_idmap *idmap, struct dentry *dentry,
2250 				 int ia_valid)
2251 {
2252 	if (unlikely(IS_PRIVATE(d_backing_inode(dentry))))
2253 		return;
2254 	call_void_hook(inode_post_setattr, idmap, dentry, ia_valid);
2255 }
2256 
2257 /**
2258  * security_inode_getattr() - Check if getting file attributes is allowed
2259  * @path: file
2260  *
2261  * Check permission before obtaining file attributes.
2262  *
2263  * Return: Returns 0 if permission is granted.
2264  */
2265 int security_inode_getattr(const struct path *path)
2266 {
2267 	if (unlikely(IS_PRIVATE(d_backing_inode(path->dentry))))
2268 		return 0;
2269 	return call_int_hook(inode_getattr, 0, path);
2270 }
2271 
2272 /**
2273  * security_inode_setxattr() - Check if setting file xattrs is allowed
2274  * @idmap: idmap of the mount
2275  * @dentry: file
2276  * @name: xattr name
2277  * @value: xattr value
2278  * @size: size of xattr value
2279  * @flags: flags
2280  *
2281  * Check permission before setting the extended attributes.
2282  *
2283  * Return: Returns 0 if permission is granted.
2284  */
2285 int security_inode_setxattr(struct mnt_idmap *idmap,
2286 			    struct dentry *dentry, const char *name,
2287 			    const void *value, size_t size, int flags)
2288 {
2289 	int ret;
2290 
2291 	if (unlikely(IS_PRIVATE(d_backing_inode(dentry))))
2292 		return 0;
2293 	/*
2294 	 * SELinux and Smack integrate the cap call,
2295 	 * so assume that all LSMs supplying this call do so.
2296 	 */
2297 	ret = call_int_hook(inode_setxattr, 1, idmap, dentry, name, value,
2298 			    size, flags);
2299 
2300 	if (ret == 1)
2301 		ret = cap_inode_setxattr(dentry, name, value, size, flags);
2302 	return ret;
2303 }
2304 
2305 /**
2306  * security_inode_set_acl() - Check if setting posix acls is allowed
2307  * @idmap: idmap of the mount
2308  * @dentry: file
2309  * @acl_name: acl name
2310  * @kacl: acl struct
2311  *
2312  * Check permission before setting posix acls, the posix acls in @kacl are
2313  * identified by @acl_name.
2314  *
2315  * Return: Returns 0 if permission is granted.
2316  */
2317 int security_inode_set_acl(struct mnt_idmap *idmap,
2318 			   struct dentry *dentry, const char *acl_name,
2319 			   struct posix_acl *kacl)
2320 {
2321 	if (unlikely(IS_PRIVATE(d_backing_inode(dentry))))
2322 		return 0;
2323 	return call_int_hook(inode_set_acl, 0, idmap, dentry, acl_name,
2324 			     kacl);
2325 }
2326 
2327 /**
2328  * security_inode_post_set_acl() - Update inode security from posix acls set
2329  * @dentry: file
2330  * @acl_name: acl name
2331  * @kacl: acl struct
2332  *
2333  * Update inode security data after successfully setting posix acls on @dentry.
2334  * The posix acls in @kacl are identified by @acl_name.
2335  */
2336 void security_inode_post_set_acl(struct dentry *dentry, const char *acl_name,
2337 				 struct posix_acl *kacl)
2338 {
2339 	if (unlikely(IS_PRIVATE(d_backing_inode(dentry))))
2340 		return;
2341 	call_void_hook(inode_post_set_acl, dentry, acl_name, kacl);
2342 }
2343 
2344 /**
2345  * security_inode_get_acl() - Check if reading posix acls is allowed
2346  * @idmap: idmap of the mount
2347  * @dentry: file
2348  * @acl_name: acl name
2349  *
2350  * Check permission before getting osix acls, the posix acls are identified by
2351  * @acl_name.
2352  *
2353  * Return: Returns 0 if permission is granted.
2354  */
2355 int security_inode_get_acl(struct mnt_idmap *idmap,
2356 			   struct dentry *dentry, const char *acl_name)
2357 {
2358 	if (unlikely(IS_PRIVATE(d_backing_inode(dentry))))
2359 		return 0;
2360 	return call_int_hook(inode_get_acl, 0, idmap, dentry, acl_name);
2361 }
2362 
2363 /**
2364  * security_inode_remove_acl() - Check if removing a posix acl is allowed
2365  * @idmap: idmap of the mount
2366  * @dentry: file
2367  * @acl_name: acl name
2368  *
2369  * Check permission before removing posix acls, the posix acls are identified
2370  * by @acl_name.
2371  *
2372  * Return: Returns 0 if permission is granted.
2373  */
2374 int security_inode_remove_acl(struct mnt_idmap *idmap,
2375 			      struct dentry *dentry, const char *acl_name)
2376 {
2377 	if (unlikely(IS_PRIVATE(d_backing_inode(dentry))))
2378 		return 0;
2379 	return call_int_hook(inode_remove_acl, 0, idmap, dentry, acl_name);
2380 }
2381 
2382 /**
2383  * security_inode_post_remove_acl() - Update inode security after rm posix acls
2384  * @idmap: idmap of the mount
2385  * @dentry: file
2386  * @acl_name: acl name
2387  *
2388  * Update inode security data after successfully removing posix acls on
2389  * @dentry in @idmap. The posix acls are identified by @acl_name.
2390  */
2391 void security_inode_post_remove_acl(struct mnt_idmap *idmap,
2392 				    struct dentry *dentry, const char *acl_name)
2393 {
2394 	if (unlikely(IS_PRIVATE(d_backing_inode(dentry))))
2395 		return;
2396 	call_void_hook(inode_post_remove_acl, idmap, dentry, acl_name);
2397 }
2398 
2399 /**
2400  * security_inode_post_setxattr() - Update the inode after a setxattr operation
2401  * @dentry: file
2402  * @name: xattr name
2403  * @value: xattr value
2404  * @size: xattr value size
2405  * @flags: flags
2406  *
2407  * Update inode security field after successful setxattr operation.
2408  */
2409 void security_inode_post_setxattr(struct dentry *dentry, const char *name,
2410 				  const void *value, size_t size, int flags)
2411 {
2412 	if (unlikely(IS_PRIVATE(d_backing_inode(dentry))))
2413 		return;
2414 	call_void_hook(inode_post_setxattr, dentry, name, value, size, flags);
2415 }
2416 
2417 /**
2418  * security_inode_getxattr() - Check if xattr access is allowed
2419  * @dentry: file
2420  * @name: xattr name
2421  *
2422  * Check permission before obtaining the extended attributes identified by
2423  * @name for @dentry.
2424  *
2425  * Return: Returns 0 if permission is granted.
2426  */
2427 int security_inode_getxattr(struct dentry *dentry, const char *name)
2428 {
2429 	if (unlikely(IS_PRIVATE(d_backing_inode(dentry))))
2430 		return 0;
2431 	return call_int_hook(inode_getxattr, 0, dentry, name);
2432 }
2433 
2434 /**
2435  * security_inode_listxattr() - Check if listing xattrs is allowed
2436  * @dentry: file
2437  *
2438  * Check permission before obtaining the list of extended attribute names for
2439  * @dentry.
2440  *
2441  * Return: Returns 0 if permission is granted.
2442  */
2443 int security_inode_listxattr(struct dentry *dentry)
2444 {
2445 	if (unlikely(IS_PRIVATE(d_backing_inode(dentry))))
2446 		return 0;
2447 	return call_int_hook(inode_listxattr, 0, dentry);
2448 }
2449 
2450 /**
2451  * security_inode_removexattr() - Check if removing an xattr is allowed
2452  * @idmap: idmap of the mount
2453  * @dentry: file
2454  * @name: xattr name
2455  *
2456  * Check permission before removing the extended attribute identified by @name
2457  * for @dentry.
2458  *
2459  * Return: Returns 0 if permission is granted.
2460  */
2461 int security_inode_removexattr(struct mnt_idmap *idmap,
2462 			       struct dentry *dentry, const char *name)
2463 {
2464 	int ret;
2465 
2466 	if (unlikely(IS_PRIVATE(d_backing_inode(dentry))))
2467 		return 0;
2468 	/*
2469 	 * SELinux and Smack integrate the cap call,
2470 	 * so assume that all LSMs supplying this call do so.
2471 	 */
2472 	ret = call_int_hook(inode_removexattr, 1, idmap, dentry, name);
2473 	if (ret == 1)
2474 		ret = cap_inode_removexattr(idmap, dentry, name);
2475 	return ret;
2476 }
2477 
2478 /**
2479  * security_inode_post_removexattr() - Update the inode after a removexattr op
2480  * @dentry: file
2481  * @name: xattr name
2482  *
2483  * Update the inode after a successful removexattr operation.
2484  */
2485 void security_inode_post_removexattr(struct dentry *dentry, const char *name)
2486 {
2487 	if (unlikely(IS_PRIVATE(d_backing_inode(dentry))))
2488 		return;
2489 	call_void_hook(inode_post_removexattr, dentry, name);
2490 }
2491 
2492 /**
2493  * security_inode_need_killpriv() - Check if security_inode_killpriv() required
2494  * @dentry: associated dentry
2495  *
2496  * Called when an inode has been changed to determine if
2497  * security_inode_killpriv() should be called.
2498  *
2499  * Return: Return <0 on error to abort the inode change operation, return 0 if
2500  *         security_inode_killpriv() does not need to be called, return >0 if
2501  *         security_inode_killpriv() does need to be called.
2502  */
2503 int security_inode_need_killpriv(struct dentry *dentry)
2504 {
2505 	return call_int_hook(inode_need_killpriv, 0, dentry);
2506 }
2507 
2508 /**
2509  * security_inode_killpriv() - The setuid bit is removed, update LSM state
2510  * @idmap: idmap of the mount
2511  * @dentry: associated dentry
2512  *
2513  * The @dentry's setuid bit is being removed.  Remove similar security labels.
2514  * Called with the dentry->d_inode->i_mutex held.
2515  *
2516  * Return: Return 0 on success.  If error is returned, then the operation
2517  *         causing setuid bit removal is failed.
2518  */
2519 int security_inode_killpriv(struct mnt_idmap *idmap,
2520 			    struct dentry *dentry)
2521 {
2522 	return call_int_hook(inode_killpriv, 0, idmap, dentry);
2523 }
2524 
2525 /**
2526  * security_inode_getsecurity() - Get the xattr security label of an inode
2527  * @idmap: idmap of the mount
2528  * @inode: inode
2529  * @name: xattr name
2530  * @buffer: security label buffer
2531  * @alloc: allocation flag
2532  *
2533  * Retrieve a copy of the extended attribute representation of the security
2534  * label associated with @name for @inode via @buffer.  Note that @name is the
2535  * remainder of the attribute name after the security prefix has been removed.
2536  * @alloc is used to specify if the call should return a value via the buffer
2537  * or just the value length.
2538  *
2539  * Return: Returns size of buffer on success.
2540  */
2541 int security_inode_getsecurity(struct mnt_idmap *idmap,
2542 			       struct inode *inode, const char *name,
2543 			       void **buffer, bool alloc)
2544 {
2545 	struct security_hook_list *hp;
2546 	int rc;
2547 
2548 	if (unlikely(IS_PRIVATE(inode)))
2549 		return LSM_RET_DEFAULT(inode_getsecurity);
2550 	/*
2551 	 * Only one module will provide an attribute with a given name.
2552 	 */
2553 	hlist_for_each_entry(hp, &security_hook_heads.inode_getsecurity, list) {
2554 		rc = hp->hook.inode_getsecurity(idmap, inode, name, buffer,
2555 						alloc);
2556 		if (rc != LSM_RET_DEFAULT(inode_getsecurity))
2557 			return rc;
2558 	}
2559 	return LSM_RET_DEFAULT(inode_getsecurity);
2560 }
2561 
2562 /**
2563  * security_inode_setsecurity() - Set the xattr security label of an inode
2564  * @inode: inode
2565  * @name: xattr name
2566  * @value: security label
2567  * @size: length of security label
2568  * @flags: flags
2569  *
2570  * Set the security label associated with @name for @inode from the extended
2571  * attribute value @value.  @size indicates the size of the @value in bytes.
2572  * @flags may be XATTR_CREATE, XATTR_REPLACE, or 0. Note that @name is the
2573  * remainder of the attribute name after the security. prefix has been removed.
2574  *
2575  * Return: Returns 0 on success.
2576  */
2577 int security_inode_setsecurity(struct inode *inode, const char *name,
2578 			       const void *value, size_t size, int flags)
2579 {
2580 	struct security_hook_list *hp;
2581 	int rc;
2582 
2583 	if (unlikely(IS_PRIVATE(inode)))
2584 		return LSM_RET_DEFAULT(inode_setsecurity);
2585 	/*
2586 	 * Only one module will provide an attribute with a given name.
2587 	 */
2588 	hlist_for_each_entry(hp, &security_hook_heads.inode_setsecurity, list) {
2589 		rc = hp->hook.inode_setsecurity(inode, name, value, size,
2590 						flags);
2591 		if (rc != LSM_RET_DEFAULT(inode_setsecurity))
2592 			return rc;
2593 	}
2594 	return LSM_RET_DEFAULT(inode_setsecurity);
2595 }
2596 
2597 /**
2598  * security_inode_listsecurity() - List the xattr security label names
2599  * @inode: inode
2600  * @buffer: buffer
2601  * @buffer_size: size of buffer
2602  *
2603  * Copy the extended attribute names for the security labels associated with
2604  * @inode into @buffer.  The maximum size of @buffer is specified by
2605  * @buffer_size.  @buffer may be NULL to request the size of the buffer
2606  * required.
2607  *
2608  * Return: Returns number of bytes used/required on success.
2609  */
2610 int security_inode_listsecurity(struct inode *inode,
2611 				char *buffer, size_t buffer_size)
2612 {
2613 	if (unlikely(IS_PRIVATE(inode)))
2614 		return 0;
2615 	return call_int_hook(inode_listsecurity, 0, inode, buffer, buffer_size);
2616 }
2617 EXPORT_SYMBOL(security_inode_listsecurity);
2618 
2619 /**
2620  * security_inode_getsecid() - Get an inode's secid
2621  * @inode: inode
2622  * @secid: secid to return
2623  *
2624  * Get the secid associated with the node.  In case of failure, @secid will be
2625  * set to zero.
2626  */
2627 void security_inode_getsecid(struct inode *inode, u32 *secid)
2628 {
2629 	call_void_hook(inode_getsecid, inode, secid);
2630 }
2631 
2632 /**
2633  * security_inode_copy_up() - Create new creds for an overlayfs copy-up op
2634  * @src: union dentry of copy-up file
2635  * @new: newly created creds
2636  *
2637  * A file is about to be copied up from lower layer to upper layer of overlay
2638  * filesystem. Security module can prepare a set of new creds and modify as
2639  * need be and return new creds. Caller will switch to new creds temporarily to
2640  * create new file and release newly allocated creds.
2641  *
2642  * Return: Returns 0 on success or a negative error code on error.
2643  */
2644 int security_inode_copy_up(struct dentry *src, struct cred **new)
2645 {
2646 	return call_int_hook(inode_copy_up, 0, src, new);
2647 }
2648 EXPORT_SYMBOL(security_inode_copy_up);
2649 
2650 /**
2651  * security_inode_copy_up_xattr() - Filter xattrs in an overlayfs copy-up op
2652  * @name: xattr name
2653  *
2654  * Filter the xattrs being copied up when a unioned file is copied up from a
2655  * lower layer to the union/overlay layer.   The caller is responsible for
2656  * reading and writing the xattrs, this hook is merely a filter.
2657  *
2658  * Return: Returns 0 to accept the xattr, 1 to discard the xattr, -EOPNOTSUPP
2659  *         if the security module does not know about attribute, or a negative
2660  *         error code to abort the copy up.
2661  */
2662 int security_inode_copy_up_xattr(const char *name)
2663 {
2664 	struct security_hook_list *hp;
2665 	int rc;
2666 
2667 	/*
2668 	 * The implementation can return 0 (accept the xattr), 1 (discard the
2669 	 * xattr), -EOPNOTSUPP if it does not know anything about the xattr or
2670 	 * any other error code in case of an error.
2671 	 */
2672 	hlist_for_each_entry(hp,
2673 			     &security_hook_heads.inode_copy_up_xattr, list) {
2674 		rc = hp->hook.inode_copy_up_xattr(name);
2675 		if (rc != LSM_RET_DEFAULT(inode_copy_up_xattr))
2676 			return rc;
2677 	}
2678 
2679 	return LSM_RET_DEFAULT(inode_copy_up_xattr);
2680 }
2681 EXPORT_SYMBOL(security_inode_copy_up_xattr);
2682 
2683 /**
2684  * security_kernfs_init_security() - Init LSM context for a kernfs node
2685  * @kn_dir: parent kernfs node
2686  * @kn: the kernfs node to initialize
2687  *
2688  * Initialize the security context of a newly created kernfs node based on its
2689  * own and its parent's attributes.
2690  *
2691  * Return: Returns 0 if permission is granted.
2692  */
2693 int security_kernfs_init_security(struct kernfs_node *kn_dir,
2694 				  struct kernfs_node *kn)
2695 {
2696 	return call_int_hook(kernfs_init_security, 0, kn_dir, kn);
2697 }
2698 
2699 /**
2700  * security_file_permission() - Check file permissions
2701  * @file: file
2702  * @mask: requested permissions
2703  *
2704  * Check file permissions before accessing an open file.  This hook is called
2705  * by various operations that read or write files.  A security module can use
2706  * this hook to perform additional checking on these operations, e.g. to
2707  * revalidate permissions on use to support privilege bracketing or policy
2708  * changes.  Notice that this hook is used when the actual read/write
2709  * operations are performed, whereas the inode_security_ops hook is called when
2710  * a file is opened (as well as many other operations).  Although this hook can
2711  * be used to revalidate permissions for various system call operations that
2712  * read or write files, it does not address the revalidation of permissions for
2713  * memory-mapped files.  Security modules must handle this separately if they
2714  * need such revalidation.
2715  *
2716  * Return: Returns 0 if permission is granted.
2717  */
2718 int security_file_permission(struct file *file, int mask)
2719 {
2720 	return call_int_hook(file_permission, 0, file, mask);
2721 }
2722 
2723 /**
2724  * security_file_alloc() - Allocate and init a file's LSM blob
2725  * @file: the file
2726  *
2727  * Allocate and attach a security structure to the file->f_security field.  The
2728  * security field is initialized to NULL when the structure is first created.
2729  *
2730  * Return: Return 0 if the hook is successful and permission is granted.
2731  */
2732 int security_file_alloc(struct file *file)
2733 {
2734 	int rc = lsm_file_alloc(file);
2735 
2736 	if (rc)
2737 		return rc;
2738 	rc = call_int_hook(file_alloc_security, 0, file);
2739 	if (unlikely(rc))
2740 		security_file_free(file);
2741 	return rc;
2742 }
2743 
2744 /**
2745  * security_file_release() - Perform actions before releasing the file ref
2746  * @file: the file
2747  *
2748  * Perform actions before releasing the last reference to a file.
2749  */
2750 void security_file_release(struct file *file)
2751 {
2752 	call_void_hook(file_release, file);
2753 }
2754 
2755 /**
2756  * security_file_free() - Free a file's LSM blob
2757  * @file: the file
2758  *
2759  * Deallocate and free any security structures stored in file->f_security.
2760  */
2761 void security_file_free(struct file *file)
2762 {
2763 	void *blob;
2764 
2765 	call_void_hook(file_free_security, file);
2766 
2767 	blob = file->f_security;
2768 	if (blob) {
2769 		file->f_security = NULL;
2770 		kmem_cache_free(lsm_file_cache, blob);
2771 	}
2772 }
2773 
2774 /**
2775  * security_file_ioctl() - Check if an ioctl is allowed
2776  * @file: associated file
2777  * @cmd: ioctl cmd
2778  * @arg: ioctl arguments
2779  *
2780  * Check permission for an ioctl operation on @file.  Note that @arg sometimes
2781  * represents a user space pointer; in other cases, it may be a simple integer
2782  * value.  When @arg represents a user space pointer, it should never be used
2783  * by the security module.
2784  *
2785  * Return: Returns 0 if permission is granted.
2786  */
2787 int security_file_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
2788 {
2789 	return call_int_hook(file_ioctl, 0, file, cmd, arg);
2790 }
2791 EXPORT_SYMBOL_GPL(security_file_ioctl);
2792 
2793 /**
2794  * security_file_ioctl_compat() - Check if an ioctl is allowed in compat mode
2795  * @file: associated file
2796  * @cmd: ioctl cmd
2797  * @arg: ioctl arguments
2798  *
2799  * Compat version of security_file_ioctl() that correctly handles 32-bit
2800  * processes running on 64-bit kernels.
2801  *
2802  * Return: Returns 0 if permission is granted.
2803  */
2804 int security_file_ioctl_compat(struct file *file, unsigned int cmd,
2805 			       unsigned long arg)
2806 {
2807 	return call_int_hook(file_ioctl_compat, 0, file, cmd, arg);
2808 }
2809 EXPORT_SYMBOL_GPL(security_file_ioctl_compat);
2810 
2811 static inline unsigned long mmap_prot(struct file *file, unsigned long prot)
2812 {
2813 	/*
2814 	 * Does we have PROT_READ and does the application expect
2815 	 * it to imply PROT_EXEC?  If not, nothing to talk about...
2816 	 */
2817 	if ((prot & (PROT_READ | PROT_EXEC)) != PROT_READ)
2818 		return prot;
2819 	if (!(current->personality & READ_IMPLIES_EXEC))
2820 		return prot;
2821 	/*
2822 	 * if that's an anonymous mapping, let it.
2823 	 */
2824 	if (!file)
2825 		return prot | PROT_EXEC;
2826 	/*
2827 	 * ditto if it's not on noexec mount, except that on !MMU we need
2828 	 * NOMMU_MAP_EXEC (== VM_MAYEXEC) in this case
2829 	 */
2830 	if (!path_noexec(&file->f_path)) {
2831 #ifndef CONFIG_MMU
2832 		if (file->f_op->mmap_capabilities) {
2833 			unsigned caps = file->f_op->mmap_capabilities(file);
2834 			if (!(caps & NOMMU_MAP_EXEC))
2835 				return prot;
2836 		}
2837 #endif
2838 		return prot | PROT_EXEC;
2839 	}
2840 	/* anything on noexec mount won't get PROT_EXEC */
2841 	return prot;
2842 }
2843 
2844 /**
2845  * security_mmap_file() - Check if mmap'ing a file is allowed
2846  * @file: file
2847  * @prot: protection applied by the kernel
2848  * @flags: flags
2849  *
2850  * Check permissions for a mmap operation.  The @file may be NULL, e.g. if
2851  * mapping anonymous memory.
2852  *
2853  * Return: Returns 0 if permission is granted.
2854  */
2855 int security_mmap_file(struct file *file, unsigned long prot,
2856 		       unsigned long flags)
2857 {
2858 	return call_int_hook(mmap_file, 0, file, prot, mmap_prot(file, prot),
2859 			     flags);
2860 }
2861 
2862 /**
2863  * security_mmap_addr() - Check if mmap'ing an address is allowed
2864  * @addr: address
2865  *
2866  * Check permissions for a mmap operation at @addr.
2867  *
2868  * Return: Returns 0 if permission is granted.
2869  */
2870 int security_mmap_addr(unsigned long addr)
2871 {
2872 	return call_int_hook(mmap_addr, 0, addr);
2873 }
2874 
2875 /**
2876  * security_file_mprotect() - Check if changing memory protections is allowed
2877  * @vma: memory region
2878  * @reqprot: application requested protection
2879  * @prot: protection applied by the kernel
2880  *
2881  * Check permissions before changing memory access permissions.
2882  *
2883  * Return: Returns 0 if permission is granted.
2884  */
2885 int security_file_mprotect(struct vm_area_struct *vma, unsigned long reqprot,
2886 			   unsigned long prot)
2887 {
2888 	return call_int_hook(file_mprotect, 0, vma, reqprot, prot);
2889 }
2890 
2891 /**
2892  * security_file_lock() - Check if a file lock is allowed
2893  * @file: file
2894  * @cmd: lock operation (e.g. F_RDLCK, F_WRLCK)
2895  *
2896  * Check permission before performing file locking operations.  Note the hook
2897  * mediates both flock and fcntl style locks.
2898  *
2899  * Return: Returns 0 if permission is granted.
2900  */
2901 int security_file_lock(struct file *file, unsigned int cmd)
2902 {
2903 	return call_int_hook(file_lock, 0, file, cmd);
2904 }
2905 
2906 /**
2907  * security_file_fcntl() - Check if fcntl() op is allowed
2908  * @file: file
2909  * @cmd: fcntl command
2910  * @arg: command argument
2911  *
2912  * Check permission before allowing the file operation specified by @cmd from
2913  * being performed on the file @file.  Note that @arg sometimes represents a
2914  * user space pointer; in other cases, it may be a simple integer value.  When
2915  * @arg represents a user space pointer, it should never be used by the
2916  * security module.
2917  *
2918  * Return: Returns 0 if permission is granted.
2919  */
2920 int security_file_fcntl(struct file *file, unsigned int cmd, unsigned long arg)
2921 {
2922 	return call_int_hook(file_fcntl, 0, file, cmd, arg);
2923 }
2924 
2925 /**
2926  * security_file_set_fowner() - Set the file owner info in the LSM blob
2927  * @file: the file
2928  *
2929  * Save owner security information (typically from current->security) in
2930  * file->f_security for later use by the send_sigiotask hook.
2931  *
2932  * Return: Returns 0 on success.
2933  */
2934 void security_file_set_fowner(struct file *file)
2935 {
2936 	call_void_hook(file_set_fowner, file);
2937 }
2938 
2939 /**
2940  * security_file_send_sigiotask() - Check if sending SIGIO/SIGURG is allowed
2941  * @tsk: target task
2942  * @fown: signal sender
2943  * @sig: signal to be sent, SIGIO is sent if 0
2944  *
2945  * Check permission for the file owner @fown to send SIGIO or SIGURG to the
2946  * process @tsk.  Note that this hook is sometimes called from interrupt.  Note
2947  * that the fown_struct, @fown, is never outside the context of a struct file,
2948  * so the file structure (and associated security information) can always be
2949  * obtained: container_of(fown, struct file, f_owner).
2950  *
2951  * Return: Returns 0 if permission is granted.
2952  */
2953 int security_file_send_sigiotask(struct task_struct *tsk,
2954 				 struct fown_struct *fown, int sig)
2955 {
2956 	return call_int_hook(file_send_sigiotask, 0, tsk, fown, sig);
2957 }
2958 
2959 /**
2960  * security_file_receive() - Check is receiving a file via IPC is allowed
2961  * @file: file being received
2962  *
2963  * This hook allows security modules to control the ability of a process to
2964  * receive an open file descriptor via socket IPC.
2965  *
2966  * Return: Returns 0 if permission is granted.
2967  */
2968 int security_file_receive(struct file *file)
2969 {
2970 	return call_int_hook(file_receive, 0, file);
2971 }
2972 
2973 /**
2974  * security_file_open() - Save open() time state for late use by the LSM
2975  * @file:
2976  *
2977  * Save open-time permission checking state for later use upon file_permission,
2978  * and recheck access if anything has changed since inode_permission.
2979  *
2980  * Return: Returns 0 if permission is granted.
2981  */
2982 int security_file_open(struct file *file)
2983 {
2984 	int ret;
2985 
2986 	ret = call_int_hook(file_open, 0, file);
2987 	if (ret)
2988 		return ret;
2989 
2990 	return fsnotify_open_perm(file);
2991 }
2992 
2993 /**
2994  * security_file_post_open() - Evaluate a file after it has been opened
2995  * @file: the file
2996  * @mask: access mask
2997  *
2998  * Evaluate an opened file and the access mask requested with open(). The hook
2999  * is useful for LSMs that require the file content to be available in order to
3000  * make decisions.
3001  *
3002  * Return: Returns 0 if permission is granted.
3003  */
3004 int security_file_post_open(struct file *file, int mask)
3005 {
3006 	return call_int_hook(file_post_open, 0, file, mask);
3007 }
3008 EXPORT_SYMBOL_GPL(security_file_post_open);
3009 
3010 /**
3011  * security_file_truncate() - Check if truncating a file is allowed
3012  * @file: file
3013  *
3014  * Check permission before truncating a file, i.e. using ftruncate.  Note that
3015  * truncation permission may also be checked based on the path, using the
3016  * @path_truncate hook.
3017  *
3018  * Return: Returns 0 if permission is granted.
3019  */
3020 int security_file_truncate(struct file *file)
3021 {
3022 	return call_int_hook(file_truncate, 0, file);
3023 }
3024 
3025 /**
3026  * security_task_alloc() - Allocate a task's LSM blob
3027  * @task: the task
3028  * @clone_flags: flags indicating what is being shared
3029  *
3030  * Handle allocation of task-related resources.
3031  *
3032  * Return: Returns a zero on success, negative values on failure.
3033  */
3034 int security_task_alloc(struct task_struct *task, unsigned long clone_flags)
3035 {
3036 	int rc = lsm_task_alloc(task);
3037 
3038 	if (rc)
3039 		return rc;
3040 	rc = call_int_hook(task_alloc, 0, task, clone_flags);
3041 	if (unlikely(rc))
3042 		security_task_free(task);
3043 	return rc;
3044 }
3045 
3046 /**
3047  * security_task_free() - Free a task's LSM blob and related resources
3048  * @task: task
3049  *
3050  * Handle release of task-related resources.  Note that this can be called from
3051  * interrupt context.
3052  */
3053 void security_task_free(struct task_struct *task)
3054 {
3055 	call_void_hook(task_free, task);
3056 
3057 	kfree(task->security);
3058 	task->security = NULL;
3059 }
3060 
3061 /**
3062  * security_cred_alloc_blank() - Allocate the min memory to allow cred_transfer
3063  * @cred: credentials
3064  * @gfp: gfp flags
3065  *
3066  * Only allocate sufficient memory and attach to @cred such that
3067  * cred_transfer() will not get ENOMEM.
3068  *
3069  * Return: Returns 0 on success, negative values on failure.
3070  */
3071 int security_cred_alloc_blank(struct cred *cred, gfp_t gfp)
3072 {
3073 	int rc = lsm_cred_alloc(cred, gfp);
3074 
3075 	if (rc)
3076 		return rc;
3077 
3078 	rc = call_int_hook(cred_alloc_blank, 0, cred, gfp);
3079 	if (unlikely(rc))
3080 		security_cred_free(cred);
3081 	return rc;
3082 }
3083 
3084 /**
3085  * security_cred_free() - Free the cred's LSM blob and associated resources
3086  * @cred: credentials
3087  *
3088  * Deallocate and clear the cred->security field in a set of credentials.
3089  */
3090 void security_cred_free(struct cred *cred)
3091 {
3092 	/*
3093 	 * There is a failure case in prepare_creds() that
3094 	 * may result in a call here with ->security being NULL.
3095 	 */
3096 	if (unlikely(cred->security == NULL))
3097 		return;
3098 
3099 	call_void_hook(cred_free, cred);
3100 
3101 	kfree(cred->security);
3102 	cred->security = NULL;
3103 }
3104 
3105 /**
3106  * security_prepare_creds() - Prepare a new set of credentials
3107  * @new: new credentials
3108  * @old: original credentials
3109  * @gfp: gfp flags
3110  *
3111  * Prepare a new set of credentials by copying the data from the old set.
3112  *
3113  * Return: Returns 0 on success, negative values on failure.
3114  */
3115 int security_prepare_creds(struct cred *new, const struct cred *old, gfp_t gfp)
3116 {
3117 	int rc = lsm_cred_alloc(new, gfp);
3118 
3119 	if (rc)
3120 		return rc;
3121 
3122 	rc = call_int_hook(cred_prepare, 0, new, old, gfp);
3123 	if (unlikely(rc))
3124 		security_cred_free(new);
3125 	return rc;
3126 }
3127 
3128 /**
3129  * security_transfer_creds() - Transfer creds
3130  * @new: target credentials
3131  * @old: original credentials
3132  *
3133  * Transfer data from original creds to new creds.
3134  */
3135 void security_transfer_creds(struct cred *new, const struct cred *old)
3136 {
3137 	call_void_hook(cred_transfer, new, old);
3138 }
3139 
3140 /**
3141  * security_cred_getsecid() - Get the secid from a set of credentials
3142  * @c: credentials
3143  * @secid: secid value
3144  *
3145  * Retrieve the security identifier of the cred structure @c.  In case of
3146  * failure, @secid will be set to zero.
3147  */
3148 void security_cred_getsecid(const struct cred *c, u32 *secid)
3149 {
3150 	*secid = 0;
3151 	call_void_hook(cred_getsecid, c, secid);
3152 }
3153 EXPORT_SYMBOL(security_cred_getsecid);
3154 
3155 /**
3156  * security_kernel_act_as() - Set the kernel credentials to act as secid
3157  * @new: credentials
3158  * @secid: secid
3159  *
3160  * Set the credentials for a kernel service to act as (subjective context).
3161  * The current task must be the one that nominated @secid.
3162  *
3163  * Return: Returns 0 if successful.
3164  */
3165 int security_kernel_act_as(struct cred *new, u32 secid)
3166 {
3167 	return call_int_hook(kernel_act_as, 0, new, secid);
3168 }
3169 
3170 /**
3171  * security_kernel_create_files_as() - Set file creation context using an inode
3172  * @new: target credentials
3173  * @inode: reference inode
3174  *
3175  * Set the file creation context in a set of credentials to be the same as the
3176  * objective context of the specified inode.  The current task must be the one
3177  * that nominated @inode.
3178  *
3179  * Return: Returns 0 if successful.
3180  */
3181 int security_kernel_create_files_as(struct cred *new, struct inode *inode)
3182 {
3183 	return call_int_hook(kernel_create_files_as, 0, new, inode);
3184 }
3185 
3186 /**
3187  * security_kernel_module_request() - Check is loading a module is allowed
3188  * @kmod_name: module name
3189  *
3190  * Ability to trigger the kernel to automatically upcall to userspace for
3191  * userspace to load a kernel module with the given name.
3192  *
3193  * Return: Returns 0 if successful.
3194  */
3195 int security_kernel_module_request(char *kmod_name)
3196 {
3197 	return call_int_hook(kernel_module_request, 0, kmod_name);
3198 }
3199 
3200 /**
3201  * security_kernel_read_file() - Read a file specified by userspace
3202  * @file: file
3203  * @id: file identifier
3204  * @contents: trust if security_kernel_post_read_file() will be called
3205  *
3206  * Read a file specified by userspace.
3207  *
3208  * Return: Returns 0 if permission is granted.
3209  */
3210 int security_kernel_read_file(struct file *file, enum kernel_read_file_id id,
3211 			      bool contents)
3212 {
3213 	return call_int_hook(kernel_read_file, 0, file, id, contents);
3214 }
3215 EXPORT_SYMBOL_GPL(security_kernel_read_file);
3216 
3217 /**
3218  * security_kernel_post_read_file() - Read a file specified by userspace
3219  * @file: file
3220  * @buf: file contents
3221  * @size: size of file contents
3222  * @id: file identifier
3223  *
3224  * Read a file specified by userspace.  This must be paired with a prior call
3225  * to security_kernel_read_file() call that indicated this hook would also be
3226  * called, see security_kernel_read_file() for more information.
3227  *
3228  * Return: Returns 0 if permission is granted.
3229  */
3230 int security_kernel_post_read_file(struct file *file, char *buf, loff_t size,
3231 				   enum kernel_read_file_id id)
3232 {
3233 	return call_int_hook(kernel_post_read_file, 0, file, buf, size, id);
3234 }
3235 EXPORT_SYMBOL_GPL(security_kernel_post_read_file);
3236 
3237 /**
3238  * security_kernel_load_data() - Load data provided by userspace
3239  * @id: data identifier
3240  * @contents: true if security_kernel_post_load_data() will be called
3241  *
3242  * Load data provided by userspace.
3243  *
3244  * Return: Returns 0 if permission is granted.
3245  */
3246 int security_kernel_load_data(enum kernel_load_data_id id, bool contents)
3247 {
3248 	return call_int_hook(kernel_load_data, 0, id, contents);
3249 }
3250 EXPORT_SYMBOL_GPL(security_kernel_load_data);
3251 
3252 /**
3253  * security_kernel_post_load_data() - Load userspace data from a non-file source
3254  * @buf: data
3255  * @size: size of data
3256  * @id: data identifier
3257  * @description: text description of data, specific to the id value
3258  *
3259  * Load data provided by a non-file source (usually userspace buffer).  This
3260  * must be paired with a prior security_kernel_load_data() call that indicated
3261  * this hook would also be called, see security_kernel_load_data() for more
3262  * information.
3263  *
3264  * Return: Returns 0 if permission is granted.
3265  */
3266 int security_kernel_post_load_data(char *buf, loff_t size,
3267 				   enum kernel_load_data_id id,
3268 				   char *description)
3269 {
3270 	return call_int_hook(kernel_post_load_data, 0, buf, size, id,
3271 			     description);
3272 }
3273 EXPORT_SYMBOL_GPL(security_kernel_post_load_data);
3274 
3275 /**
3276  * security_task_fix_setuid() - Update LSM with new user id attributes
3277  * @new: updated credentials
3278  * @old: credentials being replaced
3279  * @flags: LSM_SETID_* flag values
3280  *
3281  * Update the module's state after setting one or more of the user identity
3282  * attributes of the current process.  The @flags parameter indicates which of
3283  * the set*uid system calls invoked this hook.  If @new is the set of
3284  * credentials that will be installed.  Modifications should be made to this
3285  * rather than to @current->cred.
3286  *
3287  * Return: Returns 0 on success.
3288  */
3289 int security_task_fix_setuid(struct cred *new, const struct cred *old,
3290 			     int flags)
3291 {
3292 	return call_int_hook(task_fix_setuid, 0, new, old, flags);
3293 }
3294 
3295 /**
3296  * security_task_fix_setgid() - Update LSM with new group id attributes
3297  * @new: updated credentials
3298  * @old: credentials being replaced
3299  * @flags: LSM_SETID_* flag value
3300  *
3301  * Update the module's state after setting one or more of the group identity
3302  * attributes of the current process.  The @flags parameter indicates which of
3303  * the set*gid system calls invoked this hook.  @new is the set of credentials
3304  * that will be installed.  Modifications should be made to this rather than to
3305  * @current->cred.
3306  *
3307  * Return: Returns 0 on success.
3308  */
3309 int security_task_fix_setgid(struct cred *new, const struct cred *old,
3310 			     int flags)
3311 {
3312 	return call_int_hook(task_fix_setgid, 0, new, old, flags);
3313 }
3314 
3315 /**
3316  * security_task_fix_setgroups() - Update LSM with new supplementary groups
3317  * @new: updated credentials
3318  * @old: credentials being replaced
3319  *
3320  * Update the module's state after setting the supplementary group identity
3321  * attributes of the current process.  @new is the set of credentials that will
3322  * be installed.  Modifications should be made to this rather than to
3323  * @current->cred.
3324  *
3325  * Return: Returns 0 on success.
3326  */
3327 int security_task_fix_setgroups(struct cred *new, const struct cred *old)
3328 {
3329 	return call_int_hook(task_fix_setgroups, 0, new, old);
3330 }
3331 
3332 /**
3333  * security_task_setpgid() - Check if setting the pgid is allowed
3334  * @p: task being modified
3335  * @pgid: new pgid
3336  *
3337  * Check permission before setting the process group identifier of the process
3338  * @p to @pgid.
3339  *
3340  * Return: Returns 0 if permission is granted.
3341  */
3342 int security_task_setpgid(struct task_struct *p, pid_t pgid)
3343 {
3344 	return call_int_hook(task_setpgid, 0, p, pgid);
3345 }
3346 
3347 /**
3348  * security_task_getpgid() - Check if getting the pgid is allowed
3349  * @p: task
3350  *
3351  * Check permission before getting the process group identifier of the process
3352  * @p.
3353  *
3354  * Return: Returns 0 if permission is granted.
3355  */
3356 int security_task_getpgid(struct task_struct *p)
3357 {
3358 	return call_int_hook(task_getpgid, 0, p);
3359 }
3360 
3361 /**
3362  * security_task_getsid() - Check if getting the session id is allowed
3363  * @p: task
3364  *
3365  * Check permission before getting the session identifier of the process @p.
3366  *
3367  * Return: Returns 0 if permission is granted.
3368  */
3369 int security_task_getsid(struct task_struct *p)
3370 {
3371 	return call_int_hook(task_getsid, 0, p);
3372 }
3373 
3374 /**
3375  * security_current_getsecid_subj() - Get the current task's subjective secid
3376  * @secid: secid value
3377  *
3378  * Retrieve the subjective security identifier of the current task and return
3379  * it in @secid.  In case of failure, @secid will be set to zero.
3380  */
3381 void security_current_getsecid_subj(u32 *secid)
3382 {
3383 	*secid = 0;
3384 	call_void_hook(current_getsecid_subj, secid);
3385 }
3386 EXPORT_SYMBOL(security_current_getsecid_subj);
3387 
3388 /**
3389  * security_task_getsecid_obj() - Get a task's objective secid
3390  * @p: target task
3391  * @secid: secid value
3392  *
3393  * Retrieve the objective security identifier of the task_struct in @p and
3394  * return it in @secid. In case of failure, @secid will be set to zero.
3395  */
3396 void security_task_getsecid_obj(struct task_struct *p, u32 *secid)
3397 {
3398 	*secid = 0;
3399 	call_void_hook(task_getsecid_obj, p, secid);
3400 }
3401 EXPORT_SYMBOL(security_task_getsecid_obj);
3402 
3403 /**
3404  * security_task_setnice() - Check if setting a task's nice value is allowed
3405  * @p: target task
3406  * @nice: nice value
3407  *
3408  * Check permission before setting the nice value of @p to @nice.
3409  *
3410  * Return: Returns 0 if permission is granted.
3411  */
3412 int security_task_setnice(struct task_struct *p, int nice)
3413 {
3414 	return call_int_hook(task_setnice, 0, p, nice);
3415 }
3416 
3417 /**
3418  * security_task_setioprio() - Check if setting a task's ioprio is allowed
3419  * @p: target task
3420  * @ioprio: ioprio value
3421  *
3422  * Check permission before setting the ioprio value of @p to @ioprio.
3423  *
3424  * Return: Returns 0 if permission is granted.
3425  */
3426 int security_task_setioprio(struct task_struct *p, int ioprio)
3427 {
3428 	return call_int_hook(task_setioprio, 0, p, ioprio);
3429 }
3430 
3431 /**
3432  * security_task_getioprio() - Check if getting a task's ioprio is allowed
3433  * @p: task
3434  *
3435  * Check permission before getting the ioprio value of @p.
3436  *
3437  * Return: Returns 0 if permission is granted.
3438  */
3439 int security_task_getioprio(struct task_struct *p)
3440 {
3441 	return call_int_hook(task_getioprio, 0, p);
3442 }
3443 
3444 /**
3445  * security_task_prlimit() - Check if get/setting resources limits is allowed
3446  * @cred: current task credentials
3447  * @tcred: target task credentials
3448  * @flags: LSM_PRLIMIT_* flag bits indicating a get/set/both
3449  *
3450  * Check permission before getting and/or setting the resource limits of
3451  * another task.
3452  *
3453  * Return: Returns 0 if permission is granted.
3454  */
3455 int security_task_prlimit(const struct cred *cred, const struct cred *tcred,
3456 			  unsigned int flags)
3457 {
3458 	return call_int_hook(task_prlimit, 0, cred, tcred, flags);
3459 }
3460 
3461 /**
3462  * security_task_setrlimit() - Check if setting a new rlimit value is allowed
3463  * @p: target task's group leader
3464  * @resource: resource whose limit is being set
3465  * @new_rlim: new resource limit
3466  *
3467  * Check permission before setting the resource limits of process @p for
3468  * @resource to @new_rlim.  The old resource limit values can be examined by
3469  * dereferencing (p->signal->rlim + resource).
3470  *
3471  * Return: Returns 0 if permission is granted.
3472  */
3473 int security_task_setrlimit(struct task_struct *p, unsigned int resource,
3474 			    struct rlimit *new_rlim)
3475 {
3476 	return call_int_hook(task_setrlimit, 0, p, resource, new_rlim);
3477 }
3478 
3479 /**
3480  * security_task_setscheduler() - Check if setting sched policy/param is allowed
3481  * @p: target task
3482  *
3483  * Check permission before setting scheduling policy and/or parameters of
3484  * process @p.
3485  *
3486  * Return: Returns 0 if permission is granted.
3487  */
3488 int security_task_setscheduler(struct task_struct *p)
3489 {
3490 	return call_int_hook(task_setscheduler, 0, p);
3491 }
3492 
3493 /**
3494  * security_task_getscheduler() - Check if getting scheduling info is allowed
3495  * @p: target task
3496  *
3497  * Check permission before obtaining scheduling information for process @p.
3498  *
3499  * Return: Returns 0 if permission is granted.
3500  */
3501 int security_task_getscheduler(struct task_struct *p)
3502 {
3503 	return call_int_hook(task_getscheduler, 0, p);
3504 }
3505 
3506 /**
3507  * security_task_movememory() - Check if moving memory is allowed
3508  * @p: task
3509  *
3510  * Check permission before moving memory owned by process @p.
3511  *
3512  * Return: Returns 0 if permission is granted.
3513  */
3514 int security_task_movememory(struct task_struct *p)
3515 {
3516 	return call_int_hook(task_movememory, 0, p);
3517 }
3518 
3519 /**
3520  * security_task_kill() - Check if sending a signal is allowed
3521  * @p: target process
3522  * @info: signal information
3523  * @sig: signal value
3524  * @cred: credentials of the signal sender, NULL if @current
3525  *
3526  * Check permission before sending signal @sig to @p.  @info can be NULL, the
3527  * constant 1, or a pointer to a kernel_siginfo structure.  If @info is 1 or
3528  * SI_FROMKERNEL(info) is true, then the signal should be viewed as coming from
3529  * the kernel and should typically be permitted.  SIGIO signals are handled
3530  * separately by the send_sigiotask hook in file_security_ops.
3531  *
3532  * Return: Returns 0 if permission is granted.
3533  */
3534 int security_task_kill(struct task_struct *p, struct kernel_siginfo *info,
3535 		       int sig, const struct cred *cred)
3536 {
3537 	return call_int_hook(task_kill, 0, p, info, sig, cred);
3538 }
3539 
3540 /**
3541  * security_task_prctl() - Check if a prctl op is allowed
3542  * @option: operation
3543  * @arg2: argument
3544  * @arg3: argument
3545  * @arg4: argument
3546  * @arg5: argument
3547  *
3548  * Check permission before performing a process control operation on the
3549  * current process.
3550  *
3551  * Return: Return -ENOSYS if no-one wanted to handle this op, any other value
3552  *         to cause prctl() to return immediately with that value.
3553  */
3554 int security_task_prctl(int option, unsigned long arg2, unsigned long arg3,
3555 			unsigned long arg4, unsigned long arg5)
3556 {
3557 	int thisrc;
3558 	int rc = LSM_RET_DEFAULT(task_prctl);
3559 	struct security_hook_list *hp;
3560 
3561 	hlist_for_each_entry(hp, &security_hook_heads.task_prctl, list) {
3562 		thisrc = hp->hook.task_prctl(option, arg2, arg3, arg4, arg5);
3563 		if (thisrc != LSM_RET_DEFAULT(task_prctl)) {
3564 			rc = thisrc;
3565 			if (thisrc != 0)
3566 				break;
3567 		}
3568 	}
3569 	return rc;
3570 }
3571 
3572 /**
3573  * security_task_to_inode() - Set the security attributes of a task's inode
3574  * @p: task
3575  * @inode: inode
3576  *
3577  * Set the security attributes for an inode based on an associated task's
3578  * security attributes, e.g. for /proc/pid inodes.
3579  */
3580 void security_task_to_inode(struct task_struct *p, struct inode *inode)
3581 {
3582 	call_void_hook(task_to_inode, p, inode);
3583 }
3584 
3585 /**
3586  * security_create_user_ns() - Check if creating a new userns is allowed
3587  * @cred: prepared creds
3588  *
3589  * Check permission prior to creating a new user namespace.
3590  *
3591  * Return: Returns 0 if successful, otherwise < 0 error code.
3592  */
3593 int security_create_user_ns(const struct cred *cred)
3594 {
3595 	return call_int_hook(userns_create, 0, cred);
3596 }
3597 
3598 /**
3599  * security_ipc_permission() - Check if sysv ipc access is allowed
3600  * @ipcp: ipc permission structure
3601  * @flag: requested permissions
3602  *
3603  * Check permissions for access to IPC.
3604  *
3605  * Return: Returns 0 if permission is granted.
3606  */
3607 int security_ipc_permission(struct kern_ipc_perm *ipcp, short flag)
3608 {
3609 	return call_int_hook(ipc_permission, 0, ipcp, flag);
3610 }
3611 
3612 /**
3613  * security_ipc_getsecid() - Get the sysv ipc object's secid
3614  * @ipcp: ipc permission structure
3615  * @secid: secid pointer
3616  *
3617  * Get the secid associated with the ipc object.  In case of failure, @secid
3618  * will be set to zero.
3619  */
3620 void security_ipc_getsecid(struct kern_ipc_perm *ipcp, u32 *secid)
3621 {
3622 	*secid = 0;
3623 	call_void_hook(ipc_getsecid, ipcp, secid);
3624 }
3625 
3626 /**
3627  * security_msg_msg_alloc() - Allocate a sysv ipc message LSM blob
3628  * @msg: message structure
3629  *
3630  * Allocate and attach a security structure to the msg->security field.  The
3631  * security field is initialized to NULL when the structure is first created.
3632  *
3633  * Return: Return 0 if operation was successful and permission is granted.
3634  */
3635 int security_msg_msg_alloc(struct msg_msg *msg)
3636 {
3637 	int rc = lsm_msg_msg_alloc(msg);
3638 
3639 	if (unlikely(rc))
3640 		return rc;
3641 	rc = call_int_hook(msg_msg_alloc_security, 0, msg);
3642 	if (unlikely(rc))
3643 		security_msg_msg_free(msg);
3644 	return rc;
3645 }
3646 
3647 /**
3648  * security_msg_msg_free() - Free a sysv ipc message LSM blob
3649  * @msg: message structure
3650  *
3651  * Deallocate the security structure for this message.
3652  */
3653 void security_msg_msg_free(struct msg_msg *msg)
3654 {
3655 	call_void_hook(msg_msg_free_security, msg);
3656 	kfree(msg->security);
3657 	msg->security = NULL;
3658 }
3659 
3660 /**
3661  * security_msg_queue_alloc() - Allocate a sysv ipc msg queue LSM blob
3662  * @msq: sysv ipc permission structure
3663  *
3664  * Allocate and attach a security structure to @msg. The security field is
3665  * initialized to NULL when the structure is first created.
3666  *
3667  * Return: Returns 0 if operation was successful and permission is granted.
3668  */
3669 int security_msg_queue_alloc(struct kern_ipc_perm *msq)
3670 {
3671 	int rc = lsm_ipc_alloc(msq);
3672 
3673 	if (unlikely(rc))
3674 		return rc;
3675 	rc = call_int_hook(msg_queue_alloc_security, 0, msq);
3676 	if (unlikely(rc))
3677 		security_msg_queue_free(msq);
3678 	return rc;
3679 }
3680 
3681 /**
3682  * security_msg_queue_free() - Free a sysv ipc msg queue LSM blob
3683  * @msq: sysv ipc permission structure
3684  *
3685  * Deallocate security field @perm->security for the message queue.
3686  */
3687 void security_msg_queue_free(struct kern_ipc_perm *msq)
3688 {
3689 	call_void_hook(msg_queue_free_security, msq);
3690 	kfree(msq->security);
3691 	msq->security = NULL;
3692 }
3693 
3694 /**
3695  * security_msg_queue_associate() - Check if a msg queue operation is allowed
3696  * @msq: sysv ipc permission structure
3697  * @msqflg: operation flags
3698  *
3699  * Check permission when a message queue is requested through the msgget system
3700  * call. This hook is only called when returning the message queue identifier
3701  * for an existing message queue, not when a new message queue is created.
3702  *
3703  * Return: Return 0 if permission is granted.
3704  */
3705 int security_msg_queue_associate(struct kern_ipc_perm *msq, int msqflg)
3706 {
3707 	return call_int_hook(msg_queue_associate, 0, msq, msqflg);
3708 }
3709 
3710 /**
3711  * security_msg_queue_msgctl() - Check if a msg queue operation is allowed
3712  * @msq: sysv ipc permission structure
3713  * @cmd: operation
3714  *
3715  * Check permission when a message control operation specified by @cmd is to be
3716  * performed on the message queue with permissions.
3717  *
3718  * Return: Returns 0 if permission is granted.
3719  */
3720 int security_msg_queue_msgctl(struct kern_ipc_perm *msq, int cmd)
3721 {
3722 	return call_int_hook(msg_queue_msgctl, 0, msq, cmd);
3723 }
3724 
3725 /**
3726  * security_msg_queue_msgsnd() - Check if sending a sysv ipc message is allowed
3727  * @msq: sysv ipc permission structure
3728  * @msg: message
3729  * @msqflg: operation flags
3730  *
3731  * Check permission before a message, @msg, is enqueued on the message queue
3732  * with permissions specified in @msq.
3733  *
3734  * Return: Returns 0 if permission is granted.
3735  */
3736 int security_msg_queue_msgsnd(struct kern_ipc_perm *msq,
3737 			      struct msg_msg *msg, int msqflg)
3738 {
3739 	return call_int_hook(msg_queue_msgsnd, 0, msq, msg, msqflg);
3740 }
3741 
3742 /**
3743  * security_msg_queue_msgrcv() - Check if receiving a sysv ipc msg is allowed
3744  * @msq: sysv ipc permission structure
3745  * @msg: message
3746  * @target: target task
3747  * @type: type of message requested
3748  * @mode: operation flags
3749  *
3750  * Check permission before a message, @msg, is removed from the message	queue.
3751  * The @target task structure contains a pointer to the process that will be
3752  * receiving the message (not equal to the current process when inline receives
3753  * are being performed).
3754  *
3755  * Return: Returns 0 if permission is granted.
3756  */
3757 int security_msg_queue_msgrcv(struct kern_ipc_perm *msq, struct msg_msg *msg,
3758 			      struct task_struct *target, long type, int mode)
3759 {
3760 	return call_int_hook(msg_queue_msgrcv, 0, msq, msg, target, type, mode);
3761 }
3762 
3763 /**
3764  * security_shm_alloc() - Allocate a sysv shm LSM blob
3765  * @shp: sysv ipc permission structure
3766  *
3767  * Allocate and attach a security structure to the @shp security field.  The
3768  * security field is initialized to NULL when the structure is first created.
3769  *
3770  * Return: Returns 0 if operation was successful and permission is granted.
3771  */
3772 int security_shm_alloc(struct kern_ipc_perm *shp)
3773 {
3774 	int rc = lsm_ipc_alloc(shp);
3775 
3776 	if (unlikely(rc))
3777 		return rc;
3778 	rc = call_int_hook(shm_alloc_security, 0, shp);
3779 	if (unlikely(rc))
3780 		security_shm_free(shp);
3781 	return rc;
3782 }
3783 
3784 /**
3785  * security_shm_free() - Free a sysv shm LSM blob
3786  * @shp: sysv ipc permission structure
3787  *
3788  * Deallocate the security structure @perm->security for the memory segment.
3789  */
3790 void security_shm_free(struct kern_ipc_perm *shp)
3791 {
3792 	call_void_hook(shm_free_security, shp);
3793 	kfree(shp->security);
3794 	shp->security = NULL;
3795 }
3796 
3797 /**
3798  * security_shm_associate() - Check if a sysv shm operation is allowed
3799  * @shp: sysv ipc permission structure
3800  * @shmflg: operation flags
3801  *
3802  * Check permission when a shared memory region is requested through the shmget
3803  * system call. This hook is only called when returning the shared memory
3804  * region identifier for an existing region, not when a new shared memory
3805  * region is created.
3806  *
3807  * Return: Returns 0 if permission is granted.
3808  */
3809 int security_shm_associate(struct kern_ipc_perm *shp, int shmflg)
3810 {
3811 	return call_int_hook(shm_associate, 0, shp, shmflg);
3812 }
3813 
3814 /**
3815  * security_shm_shmctl() - Check if a sysv shm operation is allowed
3816  * @shp: sysv ipc permission structure
3817  * @cmd: operation
3818  *
3819  * Check permission when a shared memory control operation specified by @cmd is
3820  * to be performed on the shared memory region with permissions in @shp.
3821  *
3822  * Return: Return 0 if permission is granted.
3823  */
3824 int security_shm_shmctl(struct kern_ipc_perm *shp, int cmd)
3825 {
3826 	return call_int_hook(shm_shmctl, 0, shp, cmd);
3827 }
3828 
3829 /**
3830  * security_shm_shmat() - Check if a sysv shm attach operation is allowed
3831  * @shp: sysv ipc permission structure
3832  * @shmaddr: address of memory region to attach
3833  * @shmflg: operation flags
3834  *
3835  * Check permissions prior to allowing the shmat system call to attach the
3836  * shared memory segment with permissions @shp to the data segment of the
3837  * calling process. The attaching address is specified by @shmaddr.
3838  *
3839  * Return: Returns 0 if permission is granted.
3840  */
3841 int security_shm_shmat(struct kern_ipc_perm *shp,
3842 		       char __user *shmaddr, int shmflg)
3843 {
3844 	return call_int_hook(shm_shmat, 0, shp, shmaddr, shmflg);
3845 }
3846 
3847 /**
3848  * security_sem_alloc() - Allocate a sysv semaphore LSM blob
3849  * @sma: sysv ipc permission structure
3850  *
3851  * Allocate and attach a security structure to the @sma security field. The
3852  * security field is initialized to NULL when the structure is first created.
3853  *
3854  * Return: Returns 0 if operation was successful and permission is granted.
3855  */
3856 int security_sem_alloc(struct kern_ipc_perm *sma)
3857 {
3858 	int rc = lsm_ipc_alloc(sma);
3859 
3860 	if (unlikely(rc))
3861 		return rc;
3862 	rc = call_int_hook(sem_alloc_security, 0, sma);
3863 	if (unlikely(rc))
3864 		security_sem_free(sma);
3865 	return rc;
3866 }
3867 
3868 /**
3869  * security_sem_free() - Free a sysv semaphore LSM blob
3870  * @sma: sysv ipc permission structure
3871  *
3872  * Deallocate security structure @sma->security for the semaphore.
3873  */
3874 void security_sem_free(struct kern_ipc_perm *sma)
3875 {
3876 	call_void_hook(sem_free_security, sma);
3877 	kfree(sma->security);
3878 	sma->security = NULL;
3879 }
3880 
3881 /**
3882  * security_sem_associate() - Check if a sysv semaphore operation is allowed
3883  * @sma: sysv ipc permission structure
3884  * @semflg: operation flags
3885  *
3886  * Check permission when a semaphore is requested through the semget system
3887  * call. This hook is only called when returning the semaphore identifier for
3888  * an existing semaphore, not when a new one must be created.
3889  *
3890  * Return: Returns 0 if permission is granted.
3891  */
3892 int security_sem_associate(struct kern_ipc_perm *sma, int semflg)
3893 {
3894 	return call_int_hook(sem_associate, 0, sma, semflg);
3895 }
3896 
3897 /**
3898  * security_sem_semctl() - Check if a sysv semaphore operation is allowed
3899  * @sma: sysv ipc permission structure
3900  * @cmd: operation
3901  *
3902  * Check permission when a semaphore operation specified by @cmd is to be
3903  * performed on the semaphore.
3904  *
3905  * Return: Returns 0 if permission is granted.
3906  */
3907 int security_sem_semctl(struct kern_ipc_perm *sma, int cmd)
3908 {
3909 	return call_int_hook(sem_semctl, 0, sma, cmd);
3910 }
3911 
3912 /**
3913  * security_sem_semop() - Check if a sysv semaphore operation is allowed
3914  * @sma: sysv ipc permission structure
3915  * @sops: operations to perform
3916  * @nsops: number of operations
3917  * @alter: flag indicating changes will be made
3918  *
3919  * Check permissions before performing operations on members of the semaphore
3920  * set. If the @alter flag is nonzero, the semaphore set may be modified.
3921  *
3922  * Return: Returns 0 if permission is granted.
3923  */
3924 int security_sem_semop(struct kern_ipc_perm *sma, struct sembuf *sops,
3925 		       unsigned nsops, int alter)
3926 {
3927 	return call_int_hook(sem_semop, 0, sma, sops, nsops, alter);
3928 }
3929 
3930 /**
3931  * security_d_instantiate() - Populate an inode's LSM state based on a dentry
3932  * @dentry: dentry
3933  * @inode: inode
3934  *
3935  * Fill in @inode security information for a @dentry if allowed.
3936  */
3937 void security_d_instantiate(struct dentry *dentry, struct inode *inode)
3938 {
3939 	if (unlikely(inode && IS_PRIVATE(inode)))
3940 		return;
3941 	call_void_hook(d_instantiate, dentry, inode);
3942 }
3943 EXPORT_SYMBOL(security_d_instantiate);
3944 
3945 /*
3946  * Please keep this in sync with it's counterpart in security/lsm_syscalls.c
3947  */
3948 
3949 /**
3950  * security_getselfattr - Read an LSM attribute of the current process.
3951  * @attr: which attribute to return
3952  * @uctx: the user-space destination for the information, or NULL
3953  * @size: pointer to the size of space available to receive the data
3954  * @flags: special handling options. LSM_FLAG_SINGLE indicates that only
3955  * attributes associated with the LSM identified in the passed @ctx be
3956  * reported.
3957  *
3958  * A NULL value for @uctx can be used to get both the number of attributes
3959  * and the size of the data.
3960  *
3961  * Returns the number of attributes found on success, negative value
3962  * on error. @size is reset to the total size of the data.
3963  * If @size is insufficient to contain the data -E2BIG is returned.
3964  */
3965 int security_getselfattr(unsigned int attr, struct lsm_ctx __user *uctx,
3966 			 size_t __user *size, u32 flags)
3967 {
3968 	struct security_hook_list *hp;
3969 	struct lsm_ctx lctx = { .id = LSM_ID_UNDEF, };
3970 	u8 __user *base = (u8 __user *)uctx;
3971 	size_t total = 0;
3972 	size_t entrysize;
3973 	size_t left;
3974 	bool toobig = false;
3975 	bool single = false;
3976 	int count = 0;
3977 	int rc;
3978 
3979 	if (attr == LSM_ATTR_UNDEF)
3980 		return -EINVAL;
3981 	if (size == NULL)
3982 		return -EINVAL;
3983 	if (get_user(left, size))
3984 		return -EFAULT;
3985 
3986 	if (flags) {
3987 		/*
3988 		 * Only flag supported is LSM_FLAG_SINGLE
3989 		 */
3990 		if (flags != LSM_FLAG_SINGLE || !uctx)
3991 			return -EINVAL;
3992 		if (copy_from_user(&lctx, uctx, sizeof(lctx)))
3993 			return -EFAULT;
3994 		/*
3995 		 * If the LSM ID isn't specified it is an error.
3996 		 */
3997 		if (lctx.id == LSM_ID_UNDEF)
3998 			return -EINVAL;
3999 		single = true;
4000 	}
4001 
4002 	/*
4003 	 * In the usual case gather all the data from the LSMs.
4004 	 * In the single case only get the data from the LSM specified.
4005 	 */
4006 	hlist_for_each_entry(hp, &security_hook_heads.getselfattr, list) {
4007 		if (single && lctx.id != hp->lsmid->id)
4008 			continue;
4009 		entrysize = left;
4010 		if (base)
4011 			uctx = (struct lsm_ctx __user *)(base + total);
4012 		rc = hp->hook.getselfattr(attr, uctx, &entrysize, flags);
4013 		if (rc == -EOPNOTSUPP) {
4014 			rc = 0;
4015 			continue;
4016 		}
4017 		if (rc == -E2BIG) {
4018 			rc = 0;
4019 			left = 0;
4020 			toobig = true;
4021 		} else if (rc < 0)
4022 			return rc;
4023 		else
4024 			left -= entrysize;
4025 
4026 		total += entrysize;
4027 		count += rc;
4028 		if (single)
4029 			break;
4030 	}
4031 	if (put_user(total, size))
4032 		return -EFAULT;
4033 	if (toobig)
4034 		return -E2BIG;
4035 	if (count == 0)
4036 		return LSM_RET_DEFAULT(getselfattr);
4037 	return count;
4038 }
4039 
4040 /*
4041  * Please keep this in sync with it's counterpart in security/lsm_syscalls.c
4042  */
4043 
4044 /**
4045  * security_setselfattr - Set an LSM attribute on the current process.
4046  * @attr: which attribute to set
4047  * @uctx: the user-space source for the information
4048  * @size: the size of the data
4049  * @flags: reserved for future use, must be 0
4050  *
4051  * Set an LSM attribute for the current process. The LSM, attribute
4052  * and new value are included in @uctx.
4053  *
4054  * Returns 0 on success, -EINVAL if the input is inconsistent, -EFAULT
4055  * if the user buffer is inaccessible, E2BIG if size is too big, or an
4056  * LSM specific failure.
4057  */
4058 int security_setselfattr(unsigned int attr, struct lsm_ctx __user *uctx,
4059 			 size_t size, u32 flags)
4060 {
4061 	struct security_hook_list *hp;
4062 	struct lsm_ctx *lctx;
4063 	int rc = LSM_RET_DEFAULT(setselfattr);
4064 
4065 	if (flags)
4066 		return -EINVAL;
4067 	if (size < sizeof(*lctx))
4068 		return -EINVAL;
4069 	if (size > PAGE_SIZE)
4070 		return -E2BIG;
4071 
4072 	lctx = memdup_user(uctx, size);
4073 	if (IS_ERR(lctx))
4074 		return PTR_ERR(lctx);
4075 
4076 	if (size < lctx->len || size < lctx->ctx_len + sizeof(*lctx) ||
4077 	    lctx->len < lctx->ctx_len + sizeof(*lctx)) {
4078 		rc = -EINVAL;
4079 		goto free_out;
4080 	}
4081 
4082 	hlist_for_each_entry(hp, &security_hook_heads.setselfattr, list)
4083 		if ((hp->lsmid->id) == lctx->id) {
4084 			rc = hp->hook.setselfattr(attr, lctx, size, flags);
4085 			break;
4086 		}
4087 
4088 free_out:
4089 	kfree(lctx);
4090 	return rc;
4091 }
4092 
4093 /**
4094  * security_getprocattr() - Read an attribute for a task
4095  * @p: the task
4096  * @lsmid: LSM identification
4097  * @name: attribute name
4098  * @value: attribute value
4099  *
4100  * Read attribute @name for task @p and store it into @value if allowed.
4101  *
4102  * Return: Returns the length of @value on success, a negative value otherwise.
4103  */
4104 int security_getprocattr(struct task_struct *p, int lsmid, const char *name,
4105 			 char **value)
4106 {
4107 	struct security_hook_list *hp;
4108 
4109 	hlist_for_each_entry(hp, &security_hook_heads.getprocattr, list) {
4110 		if (lsmid != 0 && lsmid != hp->lsmid->id)
4111 			continue;
4112 		return hp->hook.getprocattr(p, name, value);
4113 	}
4114 	return LSM_RET_DEFAULT(getprocattr);
4115 }
4116 
4117 /**
4118  * security_setprocattr() - Set an attribute for a task
4119  * @lsmid: LSM identification
4120  * @name: attribute name
4121  * @value: attribute value
4122  * @size: attribute value size
4123  *
4124  * Write (set) the current task's attribute @name to @value, size @size if
4125  * allowed.
4126  *
4127  * Return: Returns bytes written on success, a negative value otherwise.
4128  */
4129 int security_setprocattr(int lsmid, const char *name, void *value, size_t size)
4130 {
4131 	struct security_hook_list *hp;
4132 
4133 	hlist_for_each_entry(hp, &security_hook_heads.setprocattr, list) {
4134 		if (lsmid != 0 && lsmid != hp->lsmid->id)
4135 			continue;
4136 		return hp->hook.setprocattr(name, value, size);
4137 	}
4138 	return LSM_RET_DEFAULT(setprocattr);
4139 }
4140 
4141 /**
4142  * security_netlink_send() - Save info and check if netlink sending is allowed
4143  * @sk: sending socket
4144  * @skb: netlink message
4145  *
4146  * Save security information for a netlink message so that permission checking
4147  * can be performed when the message is processed.  The security information
4148  * can be saved using the eff_cap field of the netlink_skb_parms structure.
4149  * Also may be used to provide fine grained control over message transmission.
4150  *
4151  * Return: Returns 0 if the information was successfully saved and message is
4152  *         allowed to be transmitted.
4153  */
4154 int security_netlink_send(struct sock *sk, struct sk_buff *skb)
4155 {
4156 	return call_int_hook(netlink_send, 0, sk, skb);
4157 }
4158 
4159 /**
4160  * security_ismaclabel() - Check is the named attribute is a MAC label
4161  * @name: full extended attribute name
4162  *
4163  * Check if the extended attribute specified by @name represents a MAC label.
4164  *
4165  * Return: Returns 1 if name is a MAC attribute otherwise returns 0.
4166  */
4167 int security_ismaclabel(const char *name)
4168 {
4169 	return call_int_hook(ismaclabel, 0, name);
4170 }
4171 EXPORT_SYMBOL(security_ismaclabel);
4172 
4173 /**
4174  * security_secid_to_secctx() - Convert a secid to a secctx
4175  * @secid: secid
4176  * @secdata: secctx
4177  * @seclen: secctx length
4178  *
4179  * Convert secid to security context.  If @secdata is NULL the length of the
4180  * result will be returned in @seclen, but no @secdata will be returned.  This
4181  * does mean that the length could change between calls to check the length and
4182  * the next call which actually allocates and returns the @secdata.
4183  *
4184  * Return: Return 0 on success, error on failure.
4185  */
4186 int security_secid_to_secctx(u32 secid, char **secdata, u32 *seclen)
4187 {
4188 	struct security_hook_list *hp;
4189 	int rc;
4190 
4191 	/*
4192 	 * Currently, only one LSM can implement secid_to_secctx (i.e this
4193 	 * LSM hook is not "stackable").
4194 	 */
4195 	hlist_for_each_entry(hp, &security_hook_heads.secid_to_secctx, list) {
4196 		rc = hp->hook.secid_to_secctx(secid, secdata, seclen);
4197 		if (rc != LSM_RET_DEFAULT(secid_to_secctx))
4198 			return rc;
4199 	}
4200 
4201 	return LSM_RET_DEFAULT(secid_to_secctx);
4202 }
4203 EXPORT_SYMBOL(security_secid_to_secctx);
4204 
4205 /**
4206  * security_secctx_to_secid() - Convert a secctx to a secid
4207  * @secdata: secctx
4208  * @seclen: length of secctx
4209  * @secid: secid
4210  *
4211  * Convert security context to secid.
4212  *
4213  * Return: Returns 0 on success, error on failure.
4214  */
4215 int security_secctx_to_secid(const char *secdata, u32 seclen, u32 *secid)
4216 {
4217 	*secid = 0;
4218 	return call_int_hook(secctx_to_secid, 0, secdata, seclen, secid);
4219 }
4220 EXPORT_SYMBOL(security_secctx_to_secid);
4221 
4222 /**
4223  * security_release_secctx() - Free a secctx buffer
4224  * @secdata: secctx
4225  * @seclen: length of secctx
4226  *
4227  * Release the security context.
4228  */
4229 void security_release_secctx(char *secdata, u32 seclen)
4230 {
4231 	call_void_hook(release_secctx, secdata, seclen);
4232 }
4233 EXPORT_SYMBOL(security_release_secctx);
4234 
4235 /**
4236  * security_inode_invalidate_secctx() - Invalidate an inode's security label
4237  * @inode: inode
4238  *
4239  * Notify the security module that it must revalidate the security context of
4240  * an inode.
4241  */
4242 void security_inode_invalidate_secctx(struct inode *inode)
4243 {
4244 	call_void_hook(inode_invalidate_secctx, inode);
4245 }
4246 EXPORT_SYMBOL(security_inode_invalidate_secctx);
4247 
4248 /**
4249  * security_inode_notifysecctx() - Notify the LSM of an inode's security label
4250  * @inode: inode
4251  * @ctx: secctx
4252  * @ctxlen: length of secctx
4253  *
4254  * Notify the security module of what the security context of an inode should
4255  * be.  Initializes the incore security context managed by the security module
4256  * for this inode.  Example usage: NFS client invokes this hook to initialize
4257  * the security context in its incore inode to the value provided by the server
4258  * for the file when the server returned the file's attributes to the client.
4259  * Must be called with inode->i_mutex locked.
4260  *
4261  * Return: Returns 0 on success, error on failure.
4262  */
4263 int security_inode_notifysecctx(struct inode *inode, void *ctx, u32 ctxlen)
4264 {
4265 	return call_int_hook(inode_notifysecctx, 0, inode, ctx, ctxlen);
4266 }
4267 EXPORT_SYMBOL(security_inode_notifysecctx);
4268 
4269 /**
4270  * security_inode_setsecctx() - Change the security label of an inode
4271  * @dentry: inode
4272  * @ctx: secctx
4273  * @ctxlen: length of secctx
4274  *
4275  * Change the security context of an inode.  Updates the incore security
4276  * context managed by the security module and invokes the fs code as needed
4277  * (via __vfs_setxattr_noperm) to update any backing xattrs that represent the
4278  * context.  Example usage: NFS server invokes this hook to change the security
4279  * context in its incore inode and on the backing filesystem to a value
4280  * provided by the client on a SETATTR operation.  Must be called with
4281  * inode->i_mutex locked.
4282  *
4283  * Return: Returns 0 on success, error on failure.
4284  */
4285 int security_inode_setsecctx(struct dentry *dentry, void *ctx, u32 ctxlen)
4286 {
4287 	return call_int_hook(inode_setsecctx, 0, dentry, ctx, ctxlen);
4288 }
4289 EXPORT_SYMBOL(security_inode_setsecctx);
4290 
4291 /**
4292  * security_inode_getsecctx() - Get the security label of an inode
4293  * @inode: inode
4294  * @ctx: secctx
4295  * @ctxlen: length of secctx
4296  *
4297  * On success, returns 0 and fills out @ctx and @ctxlen with the security
4298  * context for the given @inode.
4299  *
4300  * Return: Returns 0 on success, error on failure.
4301  */
4302 int security_inode_getsecctx(struct inode *inode, void **ctx, u32 *ctxlen)
4303 {
4304 	struct security_hook_list *hp;
4305 	int rc;
4306 
4307 	/*
4308 	 * Only one module will provide a security context.
4309 	 */
4310 	hlist_for_each_entry(hp, &security_hook_heads.inode_getsecctx, list) {
4311 		rc = hp->hook.inode_getsecctx(inode, ctx, ctxlen);
4312 		if (rc != LSM_RET_DEFAULT(inode_getsecctx))
4313 			return rc;
4314 	}
4315 
4316 	return LSM_RET_DEFAULT(inode_getsecctx);
4317 }
4318 EXPORT_SYMBOL(security_inode_getsecctx);
4319 
4320 #ifdef CONFIG_WATCH_QUEUE
4321 /**
4322  * security_post_notification() - Check if a watch notification can be posted
4323  * @w_cred: credentials of the task that set the watch
4324  * @cred: credentials of the task which triggered the watch
4325  * @n: the notification
4326  *
4327  * Check to see if a watch notification can be posted to a particular queue.
4328  *
4329  * Return: Returns 0 if permission is granted.
4330  */
4331 int security_post_notification(const struct cred *w_cred,
4332 			       const struct cred *cred,
4333 			       struct watch_notification *n)
4334 {
4335 	return call_int_hook(post_notification, 0, w_cred, cred, n);
4336 }
4337 #endif /* CONFIG_WATCH_QUEUE */
4338 
4339 #ifdef CONFIG_KEY_NOTIFICATIONS
4340 /**
4341  * security_watch_key() - Check if a task is allowed to watch for key events
4342  * @key: the key to watch
4343  *
4344  * Check to see if a process is allowed to watch for event notifications from
4345  * a key or keyring.
4346  *
4347  * Return: Returns 0 if permission is granted.
4348  */
4349 int security_watch_key(struct key *key)
4350 {
4351 	return call_int_hook(watch_key, 0, key);
4352 }
4353 #endif /* CONFIG_KEY_NOTIFICATIONS */
4354 
4355 #ifdef CONFIG_SECURITY_NETWORK
4356 /**
4357  * security_unix_stream_connect() - Check if a AF_UNIX stream is allowed
4358  * @sock: originating sock
4359  * @other: peer sock
4360  * @newsk: new sock
4361  *
4362  * Check permissions before establishing a Unix domain stream connection
4363  * between @sock and @other.
4364  *
4365  * The @unix_stream_connect and @unix_may_send hooks were necessary because
4366  * Linux provides an alternative to the conventional file name space for Unix
4367  * domain sockets.  Whereas binding and connecting to sockets in the file name
4368  * space is mediated by the typical file permissions (and caught by the mknod
4369  * and permission hooks in inode_security_ops), binding and connecting to
4370  * sockets in the abstract name space is completely unmediated.  Sufficient
4371  * control of Unix domain sockets in the abstract name space isn't possible
4372  * using only the socket layer hooks, since we need to know the actual target
4373  * socket, which is not looked up until we are inside the af_unix code.
4374  *
4375  * Return: Returns 0 if permission is granted.
4376  */
4377 int security_unix_stream_connect(struct sock *sock, struct sock *other,
4378 				 struct sock *newsk)
4379 {
4380 	return call_int_hook(unix_stream_connect, 0, sock, other, newsk);
4381 }
4382 EXPORT_SYMBOL(security_unix_stream_connect);
4383 
4384 /**
4385  * security_unix_may_send() - Check if AF_UNIX socket can send datagrams
4386  * @sock: originating sock
4387  * @other: peer sock
4388  *
4389  * Check permissions before connecting or sending datagrams from @sock to
4390  * @other.
4391  *
4392  * The @unix_stream_connect and @unix_may_send hooks were necessary because
4393  * Linux provides an alternative to the conventional file name space for Unix
4394  * domain sockets.  Whereas binding and connecting to sockets in the file name
4395  * space is mediated by the typical file permissions (and caught by the mknod
4396  * and permission hooks in inode_security_ops), binding and connecting to
4397  * sockets in the abstract name space is completely unmediated.  Sufficient
4398  * control of Unix domain sockets in the abstract name space isn't possible
4399  * using only the socket layer hooks, since we need to know the actual target
4400  * socket, which is not looked up until we are inside the af_unix code.
4401  *
4402  * Return: Returns 0 if permission is granted.
4403  */
4404 int security_unix_may_send(struct socket *sock,  struct socket *other)
4405 {
4406 	return call_int_hook(unix_may_send, 0, sock, other);
4407 }
4408 EXPORT_SYMBOL(security_unix_may_send);
4409 
4410 /**
4411  * security_socket_create() - Check if creating a new socket is allowed
4412  * @family: protocol family
4413  * @type: communications type
4414  * @protocol: requested protocol
4415  * @kern: set to 1 if a kernel socket is requested
4416  *
4417  * Check permissions prior to creating a new socket.
4418  *
4419  * Return: Returns 0 if permission is granted.
4420  */
4421 int security_socket_create(int family, int type, int protocol, int kern)
4422 {
4423 	return call_int_hook(socket_create, 0, family, type, protocol, kern);
4424 }
4425 
4426 /**
4427  * security_socket_post_create() - Initialize a newly created socket
4428  * @sock: socket
4429  * @family: protocol family
4430  * @type: communications type
4431  * @protocol: requested protocol
4432  * @kern: set to 1 if a kernel socket is requested
4433  *
4434  * This hook allows a module to update or allocate a per-socket security
4435  * structure. Note that the security field was not added directly to the socket
4436  * structure, but rather, the socket security information is stored in the
4437  * associated inode.  Typically, the inode alloc_security hook will allocate
4438  * and attach security information to SOCK_INODE(sock)->i_security.  This hook
4439  * may be used to update the SOCK_INODE(sock)->i_security field with additional
4440  * information that wasn't available when the inode was allocated.
4441  *
4442  * Return: Returns 0 if permission is granted.
4443  */
4444 int security_socket_post_create(struct socket *sock, int family,
4445 				int type, int protocol, int kern)
4446 {
4447 	return call_int_hook(socket_post_create, 0, sock, family, type,
4448 			     protocol, kern);
4449 }
4450 
4451 /**
4452  * security_socket_socketpair() - Check if creating a socketpair is allowed
4453  * @socka: first socket
4454  * @sockb: second socket
4455  *
4456  * Check permissions before creating a fresh pair of sockets.
4457  *
4458  * Return: Returns 0 if permission is granted and the connection was
4459  *         established.
4460  */
4461 int security_socket_socketpair(struct socket *socka, struct socket *sockb)
4462 {
4463 	return call_int_hook(socket_socketpair, 0, socka, sockb);
4464 }
4465 EXPORT_SYMBOL(security_socket_socketpair);
4466 
4467 /**
4468  * security_socket_bind() - Check if a socket bind operation is allowed
4469  * @sock: socket
4470  * @address: requested bind address
4471  * @addrlen: length of address
4472  *
4473  * Check permission before socket protocol layer bind operation is performed
4474  * and the socket @sock is bound to the address specified in the @address
4475  * parameter.
4476  *
4477  * Return: Returns 0 if permission is granted.
4478  */
4479 int security_socket_bind(struct socket *sock,
4480 			 struct sockaddr *address, int addrlen)
4481 {
4482 	return call_int_hook(socket_bind, 0, sock, address, addrlen);
4483 }
4484 
4485 /**
4486  * security_socket_connect() - Check if a socket connect operation is allowed
4487  * @sock: socket
4488  * @address: address of remote connection point
4489  * @addrlen: length of address
4490  *
4491  * Check permission before socket protocol layer connect operation attempts to
4492  * connect socket @sock to a remote address, @address.
4493  *
4494  * Return: Returns 0 if permission is granted.
4495  */
4496 int security_socket_connect(struct socket *sock,
4497 			    struct sockaddr *address, int addrlen)
4498 {
4499 	return call_int_hook(socket_connect, 0, sock, address, addrlen);
4500 }
4501 
4502 /**
4503  * security_socket_listen() - Check if a socket is allowed to listen
4504  * @sock: socket
4505  * @backlog: connection queue size
4506  *
4507  * Check permission before socket protocol layer listen operation.
4508  *
4509  * Return: Returns 0 if permission is granted.
4510  */
4511 int security_socket_listen(struct socket *sock, int backlog)
4512 {
4513 	return call_int_hook(socket_listen, 0, sock, backlog);
4514 }
4515 
4516 /**
4517  * security_socket_accept() - Check if a socket is allowed to accept connections
4518  * @sock: listening socket
4519  * @newsock: newly creation connection socket
4520  *
4521  * Check permission before accepting a new connection.  Note that the new
4522  * socket, @newsock, has been created and some information copied to it, but
4523  * the accept operation has not actually been performed.
4524  *
4525  * Return: Returns 0 if permission is granted.
4526  */
4527 int security_socket_accept(struct socket *sock, struct socket *newsock)
4528 {
4529 	return call_int_hook(socket_accept, 0, sock, newsock);
4530 }
4531 
4532 /**
4533  * security_socket_sendmsg() - Check is sending a message is allowed
4534  * @sock: sending socket
4535  * @msg: message to send
4536  * @size: size of message
4537  *
4538  * Check permission before transmitting a message to another socket.
4539  *
4540  * Return: Returns 0 if permission is granted.
4541  */
4542 int security_socket_sendmsg(struct socket *sock, struct msghdr *msg, int size)
4543 {
4544 	return call_int_hook(socket_sendmsg, 0, sock, msg, size);
4545 }
4546 
4547 /**
4548  * security_socket_recvmsg() - Check if receiving a message is allowed
4549  * @sock: receiving socket
4550  * @msg: message to receive
4551  * @size: size of message
4552  * @flags: operational flags
4553  *
4554  * Check permission before receiving a message from a socket.
4555  *
4556  * Return: Returns 0 if permission is granted.
4557  */
4558 int security_socket_recvmsg(struct socket *sock, struct msghdr *msg,
4559 			    int size, int flags)
4560 {
4561 	return call_int_hook(socket_recvmsg, 0, sock, msg, size, flags);
4562 }
4563 
4564 /**
4565  * security_socket_getsockname() - Check if reading the socket addr is allowed
4566  * @sock: socket
4567  *
4568  * Check permission before reading the local address (name) of the socket
4569  * object.
4570  *
4571  * Return: Returns 0 if permission is granted.
4572  */
4573 int security_socket_getsockname(struct socket *sock)
4574 {
4575 	return call_int_hook(socket_getsockname, 0, sock);
4576 }
4577 
4578 /**
4579  * security_socket_getpeername() - Check if reading the peer's addr is allowed
4580  * @sock: socket
4581  *
4582  * Check permission before the remote address (name) of a socket object.
4583  *
4584  * Return: Returns 0 if permission is granted.
4585  */
4586 int security_socket_getpeername(struct socket *sock)
4587 {
4588 	return call_int_hook(socket_getpeername, 0, sock);
4589 }
4590 
4591 /**
4592  * security_socket_getsockopt() - Check if reading a socket option is allowed
4593  * @sock: socket
4594  * @level: option's protocol level
4595  * @optname: option name
4596  *
4597  * Check permissions before retrieving the options associated with socket
4598  * @sock.
4599  *
4600  * Return: Returns 0 if permission is granted.
4601  */
4602 int security_socket_getsockopt(struct socket *sock, int level, int optname)
4603 {
4604 	return call_int_hook(socket_getsockopt, 0, sock, level, optname);
4605 }
4606 
4607 /**
4608  * security_socket_setsockopt() - Check if setting a socket option is allowed
4609  * @sock: socket
4610  * @level: option's protocol level
4611  * @optname: option name
4612  *
4613  * Check permissions before setting the options associated with socket @sock.
4614  *
4615  * Return: Returns 0 if permission is granted.
4616  */
4617 int security_socket_setsockopt(struct socket *sock, int level, int optname)
4618 {
4619 	return call_int_hook(socket_setsockopt, 0, sock, level, optname);
4620 }
4621 
4622 /**
4623  * security_socket_shutdown() - Checks if shutting down the socket is allowed
4624  * @sock: socket
4625  * @how: flag indicating how sends and receives are handled
4626  *
4627  * Checks permission before all or part of a connection on the socket @sock is
4628  * shut down.
4629  *
4630  * Return: Returns 0 if permission is granted.
4631  */
4632 int security_socket_shutdown(struct socket *sock, int how)
4633 {
4634 	return call_int_hook(socket_shutdown, 0, sock, how);
4635 }
4636 
4637 /**
4638  * security_sock_rcv_skb() - Check if an incoming network packet is allowed
4639  * @sk: destination sock
4640  * @skb: incoming packet
4641  *
4642  * Check permissions on incoming network packets.  This hook is distinct from
4643  * Netfilter's IP input hooks since it is the first time that the incoming
4644  * sk_buff @skb has been associated with a particular socket, @sk.  Must not
4645  * sleep inside this hook because some callers hold spinlocks.
4646  *
4647  * Return: Returns 0 if permission is granted.
4648  */
4649 int security_sock_rcv_skb(struct sock *sk, struct sk_buff *skb)
4650 {
4651 	return call_int_hook(socket_sock_rcv_skb, 0, sk, skb);
4652 }
4653 EXPORT_SYMBOL(security_sock_rcv_skb);
4654 
4655 /**
4656  * security_socket_getpeersec_stream() - Get the remote peer label
4657  * @sock: socket
4658  * @optval: destination buffer
4659  * @optlen: size of peer label copied into the buffer
4660  * @len: maximum size of the destination buffer
4661  *
4662  * This hook allows the security module to provide peer socket security state
4663  * for unix or connected tcp sockets to userspace via getsockopt SO_GETPEERSEC.
4664  * For tcp sockets this can be meaningful if the socket is associated with an
4665  * ipsec SA.
4666  *
4667  * Return: Returns 0 if all is well, otherwise, typical getsockopt return
4668  *         values.
4669  */
4670 int security_socket_getpeersec_stream(struct socket *sock, sockptr_t optval,
4671 				      sockptr_t optlen, unsigned int len)
4672 {
4673 	struct security_hook_list *hp;
4674 	int rc;
4675 
4676 	/*
4677 	 * Only one module will provide a security context.
4678 	 */
4679 	hlist_for_each_entry(hp, &security_hook_heads.socket_getpeersec_stream,
4680 			     list) {
4681 		rc = hp->hook.socket_getpeersec_stream(sock, optval, optlen,
4682 						       len);
4683 		if (rc != LSM_RET_DEFAULT(socket_getpeersec_stream))
4684 			return rc;
4685 	}
4686 	return LSM_RET_DEFAULT(socket_getpeersec_stream);
4687 }
4688 
4689 /**
4690  * security_socket_getpeersec_dgram() - Get the remote peer label
4691  * @sock: socket
4692  * @skb: datagram packet
4693  * @secid: remote peer label secid
4694  *
4695  * This hook allows the security module to provide peer socket security state
4696  * for udp sockets on a per-packet basis to userspace via getsockopt
4697  * SO_GETPEERSEC. The application must first have indicated the IP_PASSSEC
4698  * option via getsockopt. It can then retrieve the security state returned by
4699  * this hook for a packet via the SCM_SECURITY ancillary message type.
4700  *
4701  * Return: Returns 0 on success, error on failure.
4702  */
4703 int security_socket_getpeersec_dgram(struct socket *sock,
4704 				     struct sk_buff *skb, u32 *secid)
4705 {
4706 	struct security_hook_list *hp;
4707 	int rc;
4708 
4709 	/*
4710 	 * Only one module will provide a security context.
4711 	 */
4712 	hlist_for_each_entry(hp, &security_hook_heads.socket_getpeersec_dgram,
4713 			     list) {
4714 		rc = hp->hook.socket_getpeersec_dgram(sock, skb, secid);
4715 		if (rc != LSM_RET_DEFAULT(socket_getpeersec_dgram))
4716 			return rc;
4717 	}
4718 	return LSM_RET_DEFAULT(socket_getpeersec_dgram);
4719 }
4720 EXPORT_SYMBOL(security_socket_getpeersec_dgram);
4721 
4722 /**
4723  * security_sk_alloc() - Allocate and initialize a sock's LSM blob
4724  * @sk: sock
4725  * @family: protocol family
4726  * @priority: gfp flags
4727  *
4728  * Allocate and attach a security structure to the sk->sk_security field, which
4729  * is used to copy security attributes between local stream sockets.
4730  *
4731  * Return: Returns 0 on success, error on failure.
4732  */
4733 int security_sk_alloc(struct sock *sk, int family, gfp_t priority)
4734 {
4735 	return call_int_hook(sk_alloc_security, 0, sk, family, priority);
4736 }
4737 
4738 /**
4739  * security_sk_free() - Free the sock's LSM blob
4740  * @sk: sock
4741  *
4742  * Deallocate security structure.
4743  */
4744 void security_sk_free(struct sock *sk)
4745 {
4746 	call_void_hook(sk_free_security, sk);
4747 }
4748 
4749 /**
4750  * security_sk_clone() - Clone a sock's LSM state
4751  * @sk: original sock
4752  * @newsk: target sock
4753  *
4754  * Clone/copy security structure.
4755  */
4756 void security_sk_clone(const struct sock *sk, struct sock *newsk)
4757 {
4758 	call_void_hook(sk_clone_security, sk, newsk);
4759 }
4760 EXPORT_SYMBOL(security_sk_clone);
4761 
4762 /**
4763  * security_sk_classify_flow() - Set a flow's secid based on socket
4764  * @sk: original socket
4765  * @flic: target flow
4766  *
4767  * Set the target flow's secid to socket's secid.
4768  */
4769 void security_sk_classify_flow(const struct sock *sk, struct flowi_common *flic)
4770 {
4771 	call_void_hook(sk_getsecid, sk, &flic->flowic_secid);
4772 }
4773 EXPORT_SYMBOL(security_sk_classify_flow);
4774 
4775 /**
4776  * security_req_classify_flow() - Set a flow's secid based on request_sock
4777  * @req: request_sock
4778  * @flic: target flow
4779  *
4780  * Sets @flic's secid to @req's secid.
4781  */
4782 void security_req_classify_flow(const struct request_sock *req,
4783 				struct flowi_common *flic)
4784 {
4785 	call_void_hook(req_classify_flow, req, flic);
4786 }
4787 EXPORT_SYMBOL(security_req_classify_flow);
4788 
4789 /**
4790  * security_sock_graft() - Reconcile LSM state when grafting a sock on a socket
4791  * @sk: sock being grafted
4792  * @parent: target parent socket
4793  *
4794  * Sets @parent's inode secid to @sk's secid and update @sk with any necessary
4795  * LSM state from @parent.
4796  */
4797 void security_sock_graft(struct sock *sk, struct socket *parent)
4798 {
4799 	call_void_hook(sock_graft, sk, parent);
4800 }
4801 EXPORT_SYMBOL(security_sock_graft);
4802 
4803 /**
4804  * security_inet_conn_request() - Set request_sock state using incoming connect
4805  * @sk: parent listening sock
4806  * @skb: incoming connection
4807  * @req: new request_sock
4808  *
4809  * Initialize the @req LSM state based on @sk and the incoming connect in @skb.
4810  *
4811  * Return: Returns 0 if permission is granted.
4812  */
4813 int security_inet_conn_request(const struct sock *sk,
4814 			       struct sk_buff *skb, struct request_sock *req)
4815 {
4816 	return call_int_hook(inet_conn_request, 0, sk, skb, req);
4817 }
4818 EXPORT_SYMBOL(security_inet_conn_request);
4819 
4820 /**
4821  * security_inet_csk_clone() - Set new sock LSM state based on request_sock
4822  * @newsk: new sock
4823  * @req: connection request_sock
4824  *
4825  * Set that LSM state of @sock using the LSM state from @req.
4826  */
4827 void security_inet_csk_clone(struct sock *newsk,
4828 			     const struct request_sock *req)
4829 {
4830 	call_void_hook(inet_csk_clone, newsk, req);
4831 }
4832 
4833 /**
4834  * security_inet_conn_established() - Update sock's LSM state with connection
4835  * @sk: sock
4836  * @skb: connection packet
4837  *
4838  * Update @sock's LSM state to represent a new connection from @skb.
4839  */
4840 void security_inet_conn_established(struct sock *sk,
4841 				    struct sk_buff *skb)
4842 {
4843 	call_void_hook(inet_conn_established, sk, skb);
4844 }
4845 EXPORT_SYMBOL(security_inet_conn_established);
4846 
4847 /**
4848  * security_secmark_relabel_packet() - Check if setting a secmark is allowed
4849  * @secid: new secmark value
4850  *
4851  * Check if the process should be allowed to relabel packets to @secid.
4852  *
4853  * Return: Returns 0 if permission is granted.
4854  */
4855 int security_secmark_relabel_packet(u32 secid)
4856 {
4857 	return call_int_hook(secmark_relabel_packet, 0, secid);
4858 }
4859 EXPORT_SYMBOL(security_secmark_relabel_packet);
4860 
4861 /**
4862  * security_secmark_refcount_inc() - Increment the secmark labeling rule count
4863  *
4864  * Tells the LSM to increment the number of secmark labeling rules loaded.
4865  */
4866 void security_secmark_refcount_inc(void)
4867 {
4868 	call_void_hook(secmark_refcount_inc);
4869 }
4870 EXPORT_SYMBOL(security_secmark_refcount_inc);
4871 
4872 /**
4873  * security_secmark_refcount_dec() - Decrement the secmark labeling rule count
4874  *
4875  * Tells the LSM to decrement the number of secmark labeling rules loaded.
4876  */
4877 void security_secmark_refcount_dec(void)
4878 {
4879 	call_void_hook(secmark_refcount_dec);
4880 }
4881 EXPORT_SYMBOL(security_secmark_refcount_dec);
4882 
4883 /**
4884  * security_tun_dev_alloc_security() - Allocate a LSM blob for a TUN device
4885  * @security: pointer to the LSM blob
4886  *
4887  * This hook allows a module to allocate a security structure for a TUN	device,
4888  * returning the pointer in @security.
4889  *
4890  * Return: Returns a zero on success, negative values on failure.
4891  */
4892 int security_tun_dev_alloc_security(void **security)
4893 {
4894 	return call_int_hook(tun_dev_alloc_security, 0, security);
4895 }
4896 EXPORT_SYMBOL(security_tun_dev_alloc_security);
4897 
4898 /**
4899  * security_tun_dev_free_security() - Free a TUN device LSM blob
4900  * @security: LSM blob
4901  *
4902  * This hook allows a module to free the security structure for a TUN device.
4903  */
4904 void security_tun_dev_free_security(void *security)
4905 {
4906 	call_void_hook(tun_dev_free_security, security);
4907 }
4908 EXPORT_SYMBOL(security_tun_dev_free_security);
4909 
4910 /**
4911  * security_tun_dev_create() - Check if creating a TUN device is allowed
4912  *
4913  * Check permissions prior to creating a new TUN device.
4914  *
4915  * Return: Returns 0 if permission is granted.
4916  */
4917 int security_tun_dev_create(void)
4918 {
4919 	return call_int_hook(tun_dev_create, 0);
4920 }
4921 EXPORT_SYMBOL(security_tun_dev_create);
4922 
4923 /**
4924  * security_tun_dev_attach_queue() - Check if attaching a TUN queue is allowed
4925  * @security: TUN device LSM blob
4926  *
4927  * Check permissions prior to attaching to a TUN device queue.
4928  *
4929  * Return: Returns 0 if permission is granted.
4930  */
4931 int security_tun_dev_attach_queue(void *security)
4932 {
4933 	return call_int_hook(tun_dev_attach_queue, 0, security);
4934 }
4935 EXPORT_SYMBOL(security_tun_dev_attach_queue);
4936 
4937 /**
4938  * security_tun_dev_attach() - Update TUN device LSM state on attach
4939  * @sk: associated sock
4940  * @security: TUN device LSM blob
4941  *
4942  * This hook can be used by the module to update any security state associated
4943  * with the TUN device's sock structure.
4944  *
4945  * Return: Returns 0 if permission is granted.
4946  */
4947 int security_tun_dev_attach(struct sock *sk, void *security)
4948 {
4949 	return call_int_hook(tun_dev_attach, 0, sk, security);
4950 }
4951 EXPORT_SYMBOL(security_tun_dev_attach);
4952 
4953 /**
4954  * security_tun_dev_open() - Update TUN device LSM state on open
4955  * @security: TUN device LSM blob
4956  *
4957  * This hook can be used by the module to update any security state associated
4958  * with the TUN device's security structure.
4959  *
4960  * Return: Returns 0 if permission is granted.
4961  */
4962 int security_tun_dev_open(void *security)
4963 {
4964 	return call_int_hook(tun_dev_open, 0, security);
4965 }
4966 EXPORT_SYMBOL(security_tun_dev_open);
4967 
4968 /**
4969  * security_sctp_assoc_request() - Update the LSM on a SCTP association req
4970  * @asoc: SCTP association
4971  * @skb: packet requesting the association
4972  *
4973  * Passes the @asoc and @chunk->skb of the association INIT packet to the LSM.
4974  *
4975  * Return: Returns 0 on success, error on failure.
4976  */
4977 int security_sctp_assoc_request(struct sctp_association *asoc,
4978 				struct sk_buff *skb)
4979 {
4980 	return call_int_hook(sctp_assoc_request, 0, asoc, skb);
4981 }
4982 EXPORT_SYMBOL(security_sctp_assoc_request);
4983 
4984 /**
4985  * security_sctp_bind_connect() - Validate a list of addrs for a SCTP option
4986  * @sk: socket
4987  * @optname: SCTP option to validate
4988  * @address: list of IP addresses to validate
4989  * @addrlen: length of the address list
4990  *
4991  * Validiate permissions required for each address associated with sock	@sk.
4992  * Depending on @optname, the addresses will be treated as either a connect or
4993  * bind service. The @addrlen is calculated on each IPv4 and IPv6 address using
4994  * sizeof(struct sockaddr_in) or sizeof(struct sockaddr_in6).
4995  *
4996  * Return: Returns 0 on success, error on failure.
4997  */
4998 int security_sctp_bind_connect(struct sock *sk, int optname,
4999 			       struct sockaddr *address, int addrlen)
5000 {
5001 	return call_int_hook(sctp_bind_connect, 0, sk, optname,
5002 			     address, addrlen);
5003 }
5004 EXPORT_SYMBOL(security_sctp_bind_connect);
5005 
5006 /**
5007  * security_sctp_sk_clone() - Clone a SCTP sock's LSM state
5008  * @asoc: SCTP association
5009  * @sk: original sock
5010  * @newsk: target sock
5011  *
5012  * Called whenever a new socket is created by accept(2) (i.e. a TCP style
5013  * socket) or when a socket is 'peeled off' e.g userspace calls
5014  * sctp_peeloff(3).
5015  */
5016 void security_sctp_sk_clone(struct sctp_association *asoc, struct sock *sk,
5017 			    struct sock *newsk)
5018 {
5019 	call_void_hook(sctp_sk_clone, asoc, sk, newsk);
5020 }
5021 EXPORT_SYMBOL(security_sctp_sk_clone);
5022 
5023 /**
5024  * security_sctp_assoc_established() - Update LSM state when assoc established
5025  * @asoc: SCTP association
5026  * @skb: packet establishing the association
5027  *
5028  * Passes the @asoc and @chunk->skb of the association COOKIE_ACK packet to the
5029  * security module.
5030  *
5031  * Return: Returns 0 if permission is granted.
5032  */
5033 int security_sctp_assoc_established(struct sctp_association *asoc,
5034 				    struct sk_buff *skb)
5035 {
5036 	return call_int_hook(sctp_assoc_established, 0, asoc, skb);
5037 }
5038 EXPORT_SYMBOL(security_sctp_assoc_established);
5039 
5040 /**
5041  * security_mptcp_add_subflow() - Inherit the LSM label from the MPTCP socket
5042  * @sk: the owning MPTCP socket
5043  * @ssk: the new subflow
5044  *
5045  * Update the labeling for the given MPTCP subflow, to match the one of the
5046  * owning MPTCP socket. This hook has to be called after the socket creation and
5047  * initialization via the security_socket_create() and
5048  * security_socket_post_create() LSM hooks.
5049  *
5050  * Return: Returns 0 on success or a negative error code on failure.
5051  */
5052 int security_mptcp_add_subflow(struct sock *sk, struct sock *ssk)
5053 {
5054 	return call_int_hook(mptcp_add_subflow, 0, sk, ssk);
5055 }
5056 
5057 #endif	/* CONFIG_SECURITY_NETWORK */
5058 
5059 #ifdef CONFIG_SECURITY_INFINIBAND
5060 /**
5061  * security_ib_pkey_access() - Check if access to an IB pkey is allowed
5062  * @sec: LSM blob
5063  * @subnet_prefix: subnet prefix of the port
5064  * @pkey: IB pkey
5065  *
5066  * Check permission to access a pkey when modifying a QP.
5067  *
5068  * Return: Returns 0 if permission is granted.
5069  */
5070 int security_ib_pkey_access(void *sec, u64 subnet_prefix, u16 pkey)
5071 {
5072 	return call_int_hook(ib_pkey_access, 0, sec, subnet_prefix, pkey);
5073 }
5074 EXPORT_SYMBOL(security_ib_pkey_access);
5075 
5076 /**
5077  * security_ib_endport_manage_subnet() - Check if SMPs traffic is allowed
5078  * @sec: LSM blob
5079  * @dev_name: IB device name
5080  * @port_num: port number
5081  *
5082  * Check permissions to send and receive SMPs on a end port.
5083  *
5084  * Return: Returns 0 if permission is granted.
5085  */
5086 int security_ib_endport_manage_subnet(void *sec,
5087 				      const char *dev_name, u8 port_num)
5088 {
5089 	return call_int_hook(ib_endport_manage_subnet, 0, sec,
5090 			     dev_name, port_num);
5091 }
5092 EXPORT_SYMBOL(security_ib_endport_manage_subnet);
5093 
5094 /**
5095  * security_ib_alloc_security() - Allocate an Infiniband LSM blob
5096  * @sec: LSM blob
5097  *
5098  * Allocate a security structure for Infiniband objects.
5099  *
5100  * Return: Returns 0 on success, non-zero on failure.
5101  */
5102 int security_ib_alloc_security(void **sec)
5103 {
5104 	return call_int_hook(ib_alloc_security, 0, sec);
5105 }
5106 EXPORT_SYMBOL(security_ib_alloc_security);
5107 
5108 /**
5109  * security_ib_free_security() - Free an Infiniband LSM blob
5110  * @sec: LSM blob
5111  *
5112  * Deallocate an Infiniband security structure.
5113  */
5114 void security_ib_free_security(void *sec)
5115 {
5116 	call_void_hook(ib_free_security, sec);
5117 }
5118 EXPORT_SYMBOL(security_ib_free_security);
5119 #endif	/* CONFIG_SECURITY_INFINIBAND */
5120 
5121 #ifdef CONFIG_SECURITY_NETWORK_XFRM
5122 /**
5123  * security_xfrm_policy_alloc() - Allocate a xfrm policy LSM blob
5124  * @ctxp: xfrm security context being added to the SPD
5125  * @sec_ctx: security label provided by userspace
5126  * @gfp: gfp flags
5127  *
5128  * Allocate a security structure to the xp->security field; the security field
5129  * is initialized to NULL when the xfrm_policy is allocated.
5130  *
5131  * Return:  Return 0 if operation was successful.
5132  */
5133 int security_xfrm_policy_alloc(struct xfrm_sec_ctx **ctxp,
5134 			       struct xfrm_user_sec_ctx *sec_ctx,
5135 			       gfp_t gfp)
5136 {
5137 	return call_int_hook(xfrm_policy_alloc_security, 0, ctxp, sec_ctx, gfp);
5138 }
5139 EXPORT_SYMBOL(security_xfrm_policy_alloc);
5140 
5141 /**
5142  * security_xfrm_policy_clone() - Clone xfrm policy LSM state
5143  * @old_ctx: xfrm security context
5144  * @new_ctxp: target xfrm security context
5145  *
5146  * Allocate a security structure in new_ctxp that contains the information from
5147  * the old_ctx structure.
5148  *
5149  * Return: Return 0 if operation was successful.
5150  */
5151 int security_xfrm_policy_clone(struct xfrm_sec_ctx *old_ctx,
5152 			       struct xfrm_sec_ctx **new_ctxp)
5153 {
5154 	return call_int_hook(xfrm_policy_clone_security, 0, old_ctx, new_ctxp);
5155 }
5156 
5157 /**
5158  * security_xfrm_policy_free() - Free a xfrm security context
5159  * @ctx: xfrm security context
5160  *
5161  * Free LSM resources associated with @ctx.
5162  */
5163 void security_xfrm_policy_free(struct xfrm_sec_ctx *ctx)
5164 {
5165 	call_void_hook(xfrm_policy_free_security, ctx);
5166 }
5167 EXPORT_SYMBOL(security_xfrm_policy_free);
5168 
5169 /**
5170  * security_xfrm_policy_delete() - Check if deleting a xfrm policy is allowed
5171  * @ctx: xfrm security context
5172  *
5173  * Authorize deletion of a SPD entry.
5174  *
5175  * Return: Returns 0 if permission is granted.
5176  */
5177 int security_xfrm_policy_delete(struct xfrm_sec_ctx *ctx)
5178 {
5179 	return call_int_hook(xfrm_policy_delete_security, 0, ctx);
5180 }
5181 
5182 /**
5183  * security_xfrm_state_alloc() - Allocate a xfrm state LSM blob
5184  * @x: xfrm state being added to the SAD
5185  * @sec_ctx: security label provided by userspace
5186  *
5187  * Allocate a security structure to the @x->security field; the security field
5188  * is initialized to NULL when the xfrm_state is allocated. Set the context to
5189  * correspond to @sec_ctx.
5190  *
5191  * Return: Return 0 if operation was successful.
5192  */
5193 int security_xfrm_state_alloc(struct xfrm_state *x,
5194 			      struct xfrm_user_sec_ctx *sec_ctx)
5195 {
5196 	return call_int_hook(xfrm_state_alloc, 0, x, sec_ctx);
5197 }
5198 EXPORT_SYMBOL(security_xfrm_state_alloc);
5199 
5200 /**
5201  * security_xfrm_state_alloc_acquire() - Allocate a xfrm state LSM blob
5202  * @x: xfrm state being added to the SAD
5203  * @polsec: associated policy's security context
5204  * @secid: secid from the flow
5205  *
5206  * Allocate a security structure to the x->security field; the security field
5207  * is initialized to NULL when the xfrm_state is allocated.  Set the context to
5208  * correspond to secid.
5209  *
5210  * Return: Returns 0 if operation was successful.
5211  */
5212 int security_xfrm_state_alloc_acquire(struct xfrm_state *x,
5213 				      struct xfrm_sec_ctx *polsec, u32 secid)
5214 {
5215 	return call_int_hook(xfrm_state_alloc_acquire, 0, x, polsec, secid);
5216 }
5217 
5218 /**
5219  * security_xfrm_state_delete() - Check if deleting a xfrm state is allowed
5220  * @x: xfrm state
5221  *
5222  * Authorize deletion of x->security.
5223  *
5224  * Return: Returns 0 if permission is granted.
5225  */
5226 int security_xfrm_state_delete(struct xfrm_state *x)
5227 {
5228 	return call_int_hook(xfrm_state_delete_security, 0, x);
5229 }
5230 EXPORT_SYMBOL(security_xfrm_state_delete);
5231 
5232 /**
5233  * security_xfrm_state_free() - Free a xfrm state
5234  * @x: xfrm state
5235  *
5236  * Deallocate x->security.
5237  */
5238 void security_xfrm_state_free(struct xfrm_state *x)
5239 {
5240 	call_void_hook(xfrm_state_free_security, x);
5241 }
5242 
5243 /**
5244  * security_xfrm_policy_lookup() - Check if using a xfrm policy is allowed
5245  * @ctx: target xfrm security context
5246  * @fl_secid: flow secid used to authorize access
5247  *
5248  * Check permission when a flow selects a xfrm_policy for processing XFRMs on a
5249  * packet.  The hook is called when selecting either a per-socket policy or a
5250  * generic xfrm policy.
5251  *
5252  * Return: Return 0 if permission is granted, -ESRCH otherwise, or -errno on
5253  *         other errors.
5254  */
5255 int security_xfrm_policy_lookup(struct xfrm_sec_ctx *ctx, u32 fl_secid)
5256 {
5257 	return call_int_hook(xfrm_policy_lookup, 0, ctx, fl_secid);
5258 }
5259 
5260 /**
5261  * security_xfrm_state_pol_flow_match() - Check for a xfrm match
5262  * @x: xfrm state to match
5263  * @xp: xfrm policy to check for a match
5264  * @flic: flow to check for a match.
5265  *
5266  * Check @xp and @flic for a match with @x.
5267  *
5268  * Return: Returns 1 if there is a match.
5269  */
5270 int security_xfrm_state_pol_flow_match(struct xfrm_state *x,
5271 				       struct xfrm_policy *xp,
5272 				       const struct flowi_common *flic)
5273 {
5274 	struct security_hook_list *hp;
5275 	int rc = LSM_RET_DEFAULT(xfrm_state_pol_flow_match);
5276 
5277 	/*
5278 	 * Since this function is expected to return 0 or 1, the judgment
5279 	 * becomes difficult if multiple LSMs supply this call. Fortunately,
5280 	 * we can use the first LSM's judgment because currently only SELinux
5281 	 * supplies this call.
5282 	 *
5283 	 * For speed optimization, we explicitly break the loop rather than
5284 	 * using the macro
5285 	 */
5286 	hlist_for_each_entry(hp, &security_hook_heads.xfrm_state_pol_flow_match,
5287 			     list) {
5288 		rc = hp->hook.xfrm_state_pol_flow_match(x, xp, flic);
5289 		break;
5290 	}
5291 	return rc;
5292 }
5293 
5294 /**
5295  * security_xfrm_decode_session() - Determine the xfrm secid for a packet
5296  * @skb: xfrm packet
5297  * @secid: secid
5298  *
5299  * Decode the packet in @skb and return the security label in @secid.
5300  *
5301  * Return: Return 0 if all xfrms used have the same secid.
5302  */
5303 int security_xfrm_decode_session(struct sk_buff *skb, u32 *secid)
5304 {
5305 	return call_int_hook(xfrm_decode_session, 0, skb, secid, 1);
5306 }
5307 
5308 void security_skb_classify_flow(struct sk_buff *skb, struct flowi_common *flic)
5309 {
5310 	int rc = call_int_hook(xfrm_decode_session, 0, skb, &flic->flowic_secid,
5311 			       0);
5312 
5313 	BUG_ON(rc);
5314 }
5315 EXPORT_SYMBOL(security_skb_classify_flow);
5316 #endif	/* CONFIG_SECURITY_NETWORK_XFRM */
5317 
5318 #ifdef CONFIG_KEYS
5319 /**
5320  * security_key_alloc() - Allocate and initialize a kernel key LSM blob
5321  * @key: key
5322  * @cred: credentials
5323  * @flags: allocation flags
5324  *
5325  * Permit allocation of a key and assign security data. Note that key does not
5326  * have a serial number assigned at this point.
5327  *
5328  * Return: Return 0 if permission is granted, -ve error otherwise.
5329  */
5330 int security_key_alloc(struct key *key, const struct cred *cred,
5331 		       unsigned long flags)
5332 {
5333 	return call_int_hook(key_alloc, 0, key, cred, flags);
5334 }
5335 
5336 /**
5337  * security_key_free() - Free a kernel key LSM blob
5338  * @key: key
5339  *
5340  * Notification of destruction; free security data.
5341  */
5342 void security_key_free(struct key *key)
5343 {
5344 	call_void_hook(key_free, key);
5345 }
5346 
5347 /**
5348  * security_key_permission() - Check if a kernel key operation is allowed
5349  * @key_ref: key reference
5350  * @cred: credentials of actor requesting access
5351  * @need_perm: requested permissions
5352  *
5353  * See whether a specific operational right is granted to a process on a key.
5354  *
5355  * Return: Return 0 if permission is granted, -ve error otherwise.
5356  */
5357 int security_key_permission(key_ref_t key_ref, const struct cred *cred,
5358 			    enum key_need_perm need_perm)
5359 {
5360 	return call_int_hook(key_permission, 0, key_ref, cred, need_perm);
5361 }
5362 
5363 /**
5364  * security_key_getsecurity() - Get the key's security label
5365  * @key: key
5366  * @buffer: security label buffer
5367  *
5368  * Get a textual representation of the security context attached to a key for
5369  * the purposes of honouring KEYCTL_GETSECURITY.  This function allocates the
5370  * storage for the NUL-terminated string and the caller should free it.
5371  *
5372  * Return: Returns the length of @buffer (including terminating NUL) or -ve if
5373  *         an error occurs.  May also return 0 (and a NULL buffer pointer) if
5374  *         there is no security label assigned to the key.
5375  */
5376 int security_key_getsecurity(struct key *key, char **buffer)
5377 {
5378 	*buffer = NULL;
5379 	return call_int_hook(key_getsecurity, 0, key, buffer);
5380 }
5381 
5382 /**
5383  * security_key_post_create_or_update() - Notification of key create or update
5384  * @keyring: keyring to which the key is linked to
5385  * @key: created or updated key
5386  * @payload: data used to instantiate or update the key
5387  * @payload_len: length of payload
5388  * @flags: key flags
5389  * @create: flag indicating whether the key was created or updated
5390  *
5391  * Notify the caller of a key creation or update.
5392  */
5393 void security_key_post_create_or_update(struct key *keyring, struct key *key,
5394 					const void *payload, size_t payload_len,
5395 					unsigned long flags, bool create)
5396 {
5397 	call_void_hook(key_post_create_or_update, keyring, key, payload,
5398 		       payload_len, flags, create);
5399 }
5400 #endif	/* CONFIG_KEYS */
5401 
5402 #ifdef CONFIG_AUDIT
5403 /**
5404  * security_audit_rule_init() - Allocate and init an LSM audit rule struct
5405  * @field: audit action
5406  * @op: rule operator
5407  * @rulestr: rule context
5408  * @lsmrule: receive buffer for audit rule struct
5409  *
5410  * Allocate and initialize an LSM audit rule structure.
5411  *
5412  * Return: Return 0 if @lsmrule has been successfully set, -EINVAL in case of
5413  *         an invalid rule.
5414  */
5415 int security_audit_rule_init(u32 field, u32 op, char *rulestr, void **lsmrule)
5416 {
5417 	return call_int_hook(audit_rule_init, 0, field, op, rulestr, lsmrule);
5418 }
5419 
5420 /**
5421  * security_audit_rule_known() - Check if an audit rule contains LSM fields
5422  * @krule: audit rule
5423  *
5424  * Specifies whether given @krule contains any fields related to the current
5425  * LSM.
5426  *
5427  * Return: Returns 1 in case of relation found, 0 otherwise.
5428  */
5429 int security_audit_rule_known(struct audit_krule *krule)
5430 {
5431 	return call_int_hook(audit_rule_known, 0, krule);
5432 }
5433 
5434 /**
5435  * security_audit_rule_free() - Free an LSM audit rule struct
5436  * @lsmrule: audit rule struct
5437  *
5438  * Deallocate the LSM audit rule structure previously allocated by
5439  * audit_rule_init().
5440  */
5441 void security_audit_rule_free(void *lsmrule)
5442 {
5443 	call_void_hook(audit_rule_free, lsmrule);
5444 }
5445 
5446 /**
5447  * security_audit_rule_match() - Check if a label matches an audit rule
5448  * @secid: security label
5449  * @field: LSM audit field
5450  * @op: matching operator
5451  * @lsmrule: audit rule
5452  *
5453  * Determine if given @secid matches a rule previously approved by
5454  * security_audit_rule_known().
5455  *
5456  * Return: Returns 1 if secid matches the rule, 0 if it does not, -ERRNO on
5457  *         failure.
5458  */
5459 int security_audit_rule_match(u32 secid, u32 field, u32 op, void *lsmrule)
5460 {
5461 	return call_int_hook(audit_rule_match, 0, secid, field, op, lsmrule);
5462 }
5463 #endif /* CONFIG_AUDIT */
5464 
5465 #ifdef CONFIG_BPF_SYSCALL
5466 /**
5467  * security_bpf() - Check if the bpf syscall operation is allowed
5468  * @cmd: command
5469  * @attr: bpf attribute
5470  * @size: size
5471  *
5472  * Do a initial check for all bpf syscalls after the attribute is copied into
5473  * the kernel. The actual security module can implement their own rules to
5474  * check the specific cmd they need.
5475  *
5476  * Return: Returns 0 if permission is granted.
5477  */
5478 int security_bpf(int cmd, union bpf_attr *attr, unsigned int size)
5479 {
5480 	return call_int_hook(bpf, 0, cmd, attr, size);
5481 }
5482 
5483 /**
5484  * security_bpf_map() - Check if access to a bpf map is allowed
5485  * @map: bpf map
5486  * @fmode: mode
5487  *
5488  * Do a check when the kernel generates and returns a file descriptor for eBPF
5489  * maps.
5490  *
5491  * Return: Returns 0 if permission is granted.
5492  */
5493 int security_bpf_map(struct bpf_map *map, fmode_t fmode)
5494 {
5495 	return call_int_hook(bpf_map, 0, map, fmode);
5496 }
5497 
5498 /**
5499  * security_bpf_prog() - Check if access to a bpf program is allowed
5500  * @prog: bpf program
5501  *
5502  * Do a check when the kernel generates and returns a file descriptor for eBPF
5503  * programs.
5504  *
5505  * Return: Returns 0 if permission is granted.
5506  */
5507 int security_bpf_prog(struct bpf_prog *prog)
5508 {
5509 	return call_int_hook(bpf_prog, 0, prog);
5510 }
5511 
5512 /**
5513  * security_bpf_map_alloc() - Allocate a bpf map LSM blob
5514  * @map: bpf map
5515  *
5516  * Initialize the security field inside bpf map.
5517  *
5518  * Return: Returns 0 on success, error on failure.
5519  */
5520 int security_bpf_map_alloc(struct bpf_map *map)
5521 {
5522 	return call_int_hook(bpf_map_alloc_security, 0, map);
5523 }
5524 
5525 /**
5526  * security_bpf_prog_alloc() - Allocate a bpf program LSM blob
5527  * @aux: bpf program aux info struct
5528  *
5529  * Initialize the security field inside bpf program.
5530  *
5531  * Return: Returns 0 on success, error on failure.
5532  */
5533 int security_bpf_prog_alloc(struct bpf_prog_aux *aux)
5534 {
5535 	return call_int_hook(bpf_prog_alloc_security, 0, aux);
5536 }
5537 
5538 /**
5539  * security_bpf_map_free() - Free a bpf map's LSM blob
5540  * @map: bpf map
5541  *
5542  * Clean up the security information stored inside bpf map.
5543  */
5544 void security_bpf_map_free(struct bpf_map *map)
5545 {
5546 	call_void_hook(bpf_map_free_security, map);
5547 }
5548 
5549 /**
5550  * security_bpf_prog_free() - Free a bpf program's LSM blob
5551  * @aux: bpf program aux info struct
5552  *
5553  * Clean up the security information stored inside bpf prog.
5554  */
5555 void security_bpf_prog_free(struct bpf_prog_aux *aux)
5556 {
5557 	call_void_hook(bpf_prog_free_security, aux);
5558 }
5559 #endif /* CONFIG_BPF_SYSCALL */
5560 
5561 /**
5562  * security_locked_down() - Check if a kernel feature is allowed
5563  * @what: requested kernel feature
5564  *
5565  * Determine whether a kernel feature that potentially enables arbitrary code
5566  * execution in kernel space should be permitted.
5567  *
5568  * Return: Returns 0 if permission is granted.
5569  */
5570 int security_locked_down(enum lockdown_reason what)
5571 {
5572 	return call_int_hook(locked_down, 0, what);
5573 }
5574 EXPORT_SYMBOL(security_locked_down);
5575 
5576 #ifdef CONFIG_PERF_EVENTS
5577 /**
5578  * security_perf_event_open() - Check if a perf event open is allowed
5579  * @attr: perf event attribute
5580  * @type: type of event
5581  *
5582  * Check whether the @type of perf_event_open syscall is allowed.
5583  *
5584  * Return: Returns 0 if permission is granted.
5585  */
5586 int security_perf_event_open(struct perf_event_attr *attr, int type)
5587 {
5588 	return call_int_hook(perf_event_open, 0, attr, type);
5589 }
5590 
5591 /**
5592  * security_perf_event_alloc() - Allocate a perf event LSM blob
5593  * @event: perf event
5594  *
5595  * Allocate and save perf_event security info.
5596  *
5597  * Return: Returns 0 on success, error on failure.
5598  */
5599 int security_perf_event_alloc(struct perf_event *event)
5600 {
5601 	return call_int_hook(perf_event_alloc, 0, event);
5602 }
5603 
5604 /**
5605  * security_perf_event_free() - Free a perf event LSM blob
5606  * @event: perf event
5607  *
5608  * Release (free) perf_event security info.
5609  */
5610 void security_perf_event_free(struct perf_event *event)
5611 {
5612 	call_void_hook(perf_event_free, event);
5613 }
5614 
5615 /**
5616  * security_perf_event_read() - Check if reading a perf event label is allowed
5617  * @event: perf event
5618  *
5619  * Read perf_event security info if allowed.
5620  *
5621  * Return: Returns 0 if permission is granted.
5622  */
5623 int security_perf_event_read(struct perf_event *event)
5624 {
5625 	return call_int_hook(perf_event_read, 0, event);
5626 }
5627 
5628 /**
5629  * security_perf_event_write() - Check if writing a perf event label is allowed
5630  * @event: perf event
5631  *
5632  * Write perf_event security info if allowed.
5633  *
5634  * Return: Returns 0 if permission is granted.
5635  */
5636 int security_perf_event_write(struct perf_event *event)
5637 {
5638 	return call_int_hook(perf_event_write, 0, event);
5639 }
5640 #endif /* CONFIG_PERF_EVENTS */
5641 
5642 #ifdef CONFIG_IO_URING
5643 /**
5644  * security_uring_override_creds() - Check if overriding creds is allowed
5645  * @new: new credentials
5646  *
5647  * Check if the current task, executing an io_uring operation, is allowed to
5648  * override it's credentials with @new.
5649  *
5650  * Return: Returns 0 if permission is granted.
5651  */
5652 int security_uring_override_creds(const struct cred *new)
5653 {
5654 	return call_int_hook(uring_override_creds, 0, new);
5655 }
5656 
5657 /**
5658  * security_uring_sqpoll() - Check if IORING_SETUP_SQPOLL is allowed
5659  *
5660  * Check whether the current task is allowed to spawn a io_uring polling thread
5661  * (IORING_SETUP_SQPOLL).
5662  *
5663  * Return: Returns 0 if permission is granted.
5664  */
5665 int security_uring_sqpoll(void)
5666 {
5667 	return call_int_hook(uring_sqpoll, 0);
5668 }
5669 
5670 /**
5671  * security_uring_cmd() - Check if a io_uring passthrough command is allowed
5672  * @ioucmd: command
5673  *
5674  * Check whether the file_operations uring_cmd is allowed to run.
5675  *
5676  * Return: Returns 0 if permission is granted.
5677  */
5678 int security_uring_cmd(struct io_uring_cmd *ioucmd)
5679 {
5680 	return call_int_hook(uring_cmd, 0, ioucmd);
5681 }
5682 #endif /* CONFIG_IO_URING */
5683