1 // SPDX-License-Identifier: GPL-2.0 2 /* 3 * linux/fs/proc/base.c 4 * 5 * Copyright (C) 1991, 1992 Linus Torvalds 6 * 7 * proc base directory handling functions 8 * 9 * 1999, Al Viro. Rewritten. Now it covers the whole per-process part. 10 * Instead of using magical inumbers to determine the kind of object 11 * we allocate and fill in-core inodes upon lookup. They don't even 12 * go into icache. We cache the reference to task_struct upon lookup too. 13 * Eventually it should become a filesystem in its own. We don't use the 14 * rest of procfs anymore. 15 * 16 * 17 * Changelog: 18 * 17-Jan-2005 19 * Allan Bezerra 20 * Bruna Moreira <bruna.moreira@indt.org.br> 21 * Edjard Mota <edjard.mota@indt.org.br> 22 * Ilias Biris <ilias.biris@indt.org.br> 23 * Mauricio Lin <mauricio.lin@indt.org.br> 24 * 25 * Embedded Linux Lab - 10LE Instituto Nokia de Tecnologia - INdT 26 * 27 * A new process specific entry (smaps) included in /proc. It shows the 28 * size of rss for each memory area. The maps entry lacks information 29 * about physical memory size (rss) for each mapped file, i.e., 30 * rss information for executables and library files. 31 * This additional information is useful for any tools that need to know 32 * about physical memory consumption for a process specific library. 33 * 34 * Changelog: 35 * 21-Feb-2005 36 * Embedded Linux Lab - 10LE Instituto Nokia de Tecnologia - INdT 37 * Pud inclusion in the page table walking. 38 * 39 * ChangeLog: 40 * 10-Mar-2005 41 * 10LE Instituto Nokia de Tecnologia - INdT: 42 * A better way to walks through the page table as suggested by Hugh Dickins. 43 * 44 * Simo Piiroinen <simo.piiroinen@nokia.com>: 45 * Smaps information related to shared, private, clean and dirty pages. 46 * 47 * Paul Mundt <paul.mundt@nokia.com>: 48 * Overall revision about smaps. 49 */ 50 51 #include <linux/uaccess.h> 52 53 #include <linux/errno.h> 54 #include <linux/time.h> 55 #include <linux/proc_fs.h> 56 #include <linux/stat.h> 57 #include <linux/task_io_accounting_ops.h> 58 #include <linux/init.h> 59 #include <linux/capability.h> 60 #include <linux/file.h> 61 #include <linux/fdtable.h> 62 #include <linux/generic-radix-tree.h> 63 #include <linux/string.h> 64 #include <linux/seq_file.h> 65 #include <linux/namei.h> 66 #include <linux/mnt_namespace.h> 67 #include <linux/mm.h> 68 #include <linux/swap.h> 69 #include <linux/rcupdate.h> 70 #include <linux/kallsyms.h> 71 #include <linux/stacktrace.h> 72 #include <linux/resource.h> 73 #include <linux/module.h> 74 #include <linux/mount.h> 75 #include <linux/security.h> 76 #include <linux/ptrace.h> 77 #include <linux/printk.h> 78 #include <linux/cache.h> 79 #include <linux/cgroup.h> 80 #include <linux/cpuset.h> 81 #include <linux/audit.h> 82 #include <linux/poll.h> 83 #include <linux/nsproxy.h> 84 #include <linux/oom.h> 85 #include <linux/elf.h> 86 #include <linux/pid_namespace.h> 87 #include <linux/user_namespace.h> 88 #include <linux/fs_struct.h> 89 #include <linux/slab.h> 90 #include <linux/sched/autogroup.h> 91 #include <linux/sched/mm.h> 92 #include <linux/sched/coredump.h> 93 #include <linux/sched/debug.h> 94 #include <linux/sched/stat.h> 95 #include <linux/posix-timers.h> 96 #include <linux/time_namespace.h> 97 #include <linux/resctrl.h> 98 #include <linux/cn_proc.h> 99 #include <linux/ksm.h> 100 #include <trace/events/oom.h> 101 #include "internal.h" 102 #include "fd.h" 103 104 #include "../../lib/kstrtox.h" 105 106 /* NOTE: 107 * Implementing inode permission operations in /proc is almost 108 * certainly an error. Permission checks need to happen during 109 * each system call not at open time. The reason is that most of 110 * what we wish to check for permissions in /proc varies at runtime. 111 * 112 * The classic example of a problem is opening file descriptors 113 * in /proc for a task before it execs a suid executable. 114 */ 115 116 static u8 nlink_tid __ro_after_init; 117 static u8 nlink_tgid __ro_after_init; 118 119 struct pid_entry { 120 const char *name; 121 unsigned int len; 122 umode_t mode; 123 const struct inode_operations *iop; 124 const struct file_operations *fop; 125 union proc_op op; 126 }; 127 128 #define NOD(NAME, MODE, IOP, FOP, OP) { \ 129 .name = (NAME), \ 130 .len = sizeof(NAME) - 1, \ 131 .mode = MODE, \ 132 .iop = IOP, \ 133 .fop = FOP, \ 134 .op = OP, \ 135 } 136 137 #define DIR(NAME, MODE, iops, fops) \ 138 NOD(NAME, (S_IFDIR|(MODE)), &iops, &fops, {} ) 139 #define LNK(NAME, get_link) \ 140 NOD(NAME, (S_IFLNK|S_IRWXUGO), \ 141 &proc_pid_link_inode_operations, NULL, \ 142 { .proc_get_link = get_link } ) 143 #define REG(NAME, MODE, fops) \ 144 NOD(NAME, (S_IFREG|(MODE)), NULL, &fops, {}) 145 #define ONE(NAME, MODE, show) \ 146 NOD(NAME, (S_IFREG|(MODE)), \ 147 NULL, &proc_single_file_operations, \ 148 { .proc_show = show } ) 149 #define ATTR(LSM, NAME, MODE) \ 150 NOD(NAME, (S_IFREG|(MODE)), \ 151 NULL, &proc_pid_attr_operations, \ 152 { .lsm = LSM }) 153 154 /* 155 * Count the number of hardlinks for the pid_entry table, excluding the . 156 * and .. links. 157 */ 158 static unsigned int __init pid_entry_nlink(const struct pid_entry *entries, 159 unsigned int n) 160 { 161 unsigned int i; 162 unsigned int count; 163 164 count = 2; 165 for (i = 0; i < n; ++i) { 166 if (S_ISDIR(entries[i].mode)) 167 ++count; 168 } 169 170 return count; 171 } 172 173 static int get_task_root(struct task_struct *task, struct path *root) 174 { 175 int result = -ENOENT; 176 177 task_lock(task); 178 if (task->fs) { 179 get_fs_root(task->fs, root); 180 result = 0; 181 } 182 task_unlock(task); 183 return result; 184 } 185 186 static int proc_cwd_link(struct dentry *dentry, struct path *path) 187 { 188 struct task_struct *task = get_proc_task(d_inode(dentry)); 189 int result = -ENOENT; 190 191 if (task) { 192 task_lock(task); 193 if (task->fs) { 194 get_fs_pwd(task->fs, path); 195 result = 0; 196 } 197 task_unlock(task); 198 put_task_struct(task); 199 } 200 return result; 201 } 202 203 static int proc_root_link(struct dentry *dentry, struct path *path) 204 { 205 struct task_struct *task = get_proc_task(d_inode(dentry)); 206 int result = -ENOENT; 207 208 if (task) { 209 result = get_task_root(task, path); 210 put_task_struct(task); 211 } 212 return result; 213 } 214 215 /* 216 * If the user used setproctitle(), we just get the string from 217 * user space at arg_start, and limit it to a maximum of one page. 218 */ 219 static ssize_t get_mm_proctitle(struct mm_struct *mm, char __user *buf, 220 size_t count, unsigned long pos, 221 unsigned long arg_start) 222 { 223 char *page; 224 int ret, got; 225 226 if (pos >= PAGE_SIZE) 227 return 0; 228 229 page = (char *)__get_free_page(GFP_KERNEL); 230 if (!page) 231 return -ENOMEM; 232 233 ret = 0; 234 got = access_remote_vm(mm, arg_start, page, PAGE_SIZE, FOLL_ANON); 235 if (got > 0) { 236 int len = strnlen(page, got); 237 238 /* Include the NUL character if it was found */ 239 if (len < got) 240 len++; 241 242 if (len > pos) { 243 len -= pos; 244 if (len > count) 245 len = count; 246 len -= copy_to_user(buf, page+pos, len); 247 if (!len) 248 len = -EFAULT; 249 ret = len; 250 } 251 } 252 free_page((unsigned long)page); 253 return ret; 254 } 255 256 static ssize_t get_mm_cmdline(struct mm_struct *mm, char __user *buf, 257 size_t count, loff_t *ppos) 258 { 259 unsigned long arg_start, arg_end, env_start, env_end; 260 unsigned long pos, len; 261 char *page, c; 262 263 /* Check if process spawned far enough to have cmdline. */ 264 if (!mm->env_end) 265 return 0; 266 267 spin_lock(&mm->arg_lock); 268 arg_start = mm->arg_start; 269 arg_end = mm->arg_end; 270 env_start = mm->env_start; 271 env_end = mm->env_end; 272 spin_unlock(&mm->arg_lock); 273 274 if (arg_start >= arg_end) 275 return 0; 276 277 /* 278 * We allow setproctitle() to overwrite the argument 279 * strings, and overflow past the original end. But 280 * only when it overflows into the environment area. 281 */ 282 if (env_start != arg_end || env_end < env_start) 283 env_start = env_end = arg_end; 284 len = env_end - arg_start; 285 286 /* We're not going to care if "*ppos" has high bits set */ 287 pos = *ppos; 288 if (pos >= len) 289 return 0; 290 if (count > len - pos) 291 count = len - pos; 292 if (!count) 293 return 0; 294 295 /* 296 * Magical special case: if the argv[] end byte is not 297 * zero, the user has overwritten it with setproctitle(3). 298 * 299 * Possible future enhancement: do this only once when 300 * pos is 0, and set a flag in the 'struct file'. 301 */ 302 if (access_remote_vm(mm, arg_end-1, &c, 1, FOLL_ANON) == 1 && c) 303 return get_mm_proctitle(mm, buf, count, pos, arg_start); 304 305 /* 306 * For the non-setproctitle() case we limit things strictly 307 * to the [arg_start, arg_end[ range. 308 */ 309 pos += arg_start; 310 if (pos < arg_start || pos >= arg_end) 311 return 0; 312 if (count > arg_end - pos) 313 count = arg_end - pos; 314 315 page = (char *)__get_free_page(GFP_KERNEL); 316 if (!page) 317 return -ENOMEM; 318 319 len = 0; 320 while (count) { 321 int got; 322 size_t size = min_t(size_t, PAGE_SIZE, count); 323 324 got = access_remote_vm(mm, pos, page, size, FOLL_ANON); 325 if (got <= 0) 326 break; 327 got -= copy_to_user(buf, page, got); 328 if (unlikely(!got)) { 329 if (!len) 330 len = -EFAULT; 331 break; 332 } 333 pos += got; 334 buf += got; 335 len += got; 336 count -= got; 337 } 338 339 free_page((unsigned long)page); 340 return len; 341 } 342 343 static ssize_t get_task_cmdline(struct task_struct *tsk, char __user *buf, 344 size_t count, loff_t *pos) 345 { 346 struct mm_struct *mm; 347 ssize_t ret; 348 349 mm = get_task_mm(tsk); 350 if (!mm) 351 return 0; 352 353 ret = get_mm_cmdline(mm, buf, count, pos); 354 mmput(mm); 355 return ret; 356 } 357 358 static ssize_t proc_pid_cmdline_read(struct file *file, char __user *buf, 359 size_t count, loff_t *pos) 360 { 361 struct task_struct *tsk; 362 ssize_t ret; 363 364 BUG_ON(*pos < 0); 365 366 tsk = get_proc_task(file_inode(file)); 367 if (!tsk) 368 return -ESRCH; 369 ret = get_task_cmdline(tsk, buf, count, pos); 370 put_task_struct(tsk); 371 if (ret > 0) 372 *pos += ret; 373 return ret; 374 } 375 376 static const struct file_operations proc_pid_cmdline_ops = { 377 .read = proc_pid_cmdline_read, 378 .llseek = generic_file_llseek, 379 }; 380 381 #ifdef CONFIG_KALLSYMS 382 /* 383 * Provides a wchan file via kallsyms in a proper one-value-per-file format. 384 * Returns the resolved symbol. If that fails, simply return the address. 385 */ 386 static int proc_pid_wchan(struct seq_file *m, struct pid_namespace *ns, 387 struct pid *pid, struct task_struct *task) 388 { 389 unsigned long wchan; 390 char symname[KSYM_NAME_LEN]; 391 392 if (!ptrace_may_access(task, PTRACE_MODE_READ_FSCREDS)) 393 goto print0; 394 395 wchan = get_wchan(task); 396 if (wchan && !lookup_symbol_name(wchan, symname)) { 397 seq_puts(m, symname); 398 return 0; 399 } 400 401 print0: 402 seq_putc(m, '0'); 403 return 0; 404 } 405 #endif /* CONFIG_KALLSYMS */ 406 407 static int lock_trace(struct task_struct *task) 408 { 409 int err = down_read_killable(&task->signal->exec_update_lock); 410 if (err) 411 return err; 412 if (!ptrace_may_access(task, PTRACE_MODE_ATTACH_FSCREDS)) { 413 up_read(&task->signal->exec_update_lock); 414 return -EPERM; 415 } 416 return 0; 417 } 418 419 static void unlock_trace(struct task_struct *task) 420 { 421 up_read(&task->signal->exec_update_lock); 422 } 423 424 #ifdef CONFIG_STACKTRACE 425 426 #define MAX_STACK_TRACE_DEPTH 64 427 428 static int proc_pid_stack(struct seq_file *m, struct pid_namespace *ns, 429 struct pid *pid, struct task_struct *task) 430 { 431 unsigned long *entries; 432 int err; 433 434 /* 435 * The ability to racily run the kernel stack unwinder on a running task 436 * and then observe the unwinder output is scary; while it is useful for 437 * debugging kernel issues, it can also allow an attacker to leak kernel 438 * stack contents. 439 * Doing this in a manner that is at least safe from races would require 440 * some work to ensure that the remote task can not be scheduled; and 441 * even then, this would still expose the unwinder as local attack 442 * surface. 443 * Therefore, this interface is restricted to root. 444 */ 445 if (!file_ns_capable(m->file, &init_user_ns, CAP_SYS_ADMIN)) 446 return -EACCES; 447 448 entries = kmalloc_array(MAX_STACK_TRACE_DEPTH, sizeof(*entries), 449 GFP_KERNEL); 450 if (!entries) 451 return -ENOMEM; 452 453 err = lock_trace(task); 454 if (!err) { 455 unsigned int i, nr_entries; 456 457 nr_entries = stack_trace_save_tsk(task, entries, 458 MAX_STACK_TRACE_DEPTH, 0); 459 460 for (i = 0; i < nr_entries; i++) { 461 seq_printf(m, "[<0>] %pB\n", (void *)entries[i]); 462 } 463 464 unlock_trace(task); 465 } 466 kfree(entries); 467 468 return err; 469 } 470 #endif 471 472 #ifdef CONFIG_SCHED_INFO 473 /* 474 * Provides /proc/PID/schedstat 475 */ 476 static int proc_pid_schedstat(struct seq_file *m, struct pid_namespace *ns, 477 struct pid *pid, struct task_struct *task) 478 { 479 if (unlikely(!sched_info_on())) 480 seq_puts(m, "0 0 0\n"); 481 else 482 seq_printf(m, "%llu %llu %lu\n", 483 (unsigned long long)task->se.sum_exec_runtime, 484 (unsigned long long)task->sched_info.run_delay, 485 task->sched_info.pcount); 486 487 return 0; 488 } 489 #endif 490 491 #ifdef CONFIG_LATENCYTOP 492 static int lstats_show_proc(struct seq_file *m, void *v) 493 { 494 int i; 495 struct inode *inode = m->private; 496 struct task_struct *task = get_proc_task(inode); 497 498 if (!task) 499 return -ESRCH; 500 seq_puts(m, "Latency Top version : v0.1\n"); 501 for (i = 0; i < LT_SAVECOUNT; i++) { 502 struct latency_record *lr = &task->latency_record[i]; 503 if (lr->backtrace[0]) { 504 int q; 505 seq_printf(m, "%i %li %li", 506 lr->count, lr->time, lr->max); 507 for (q = 0; q < LT_BACKTRACEDEPTH; q++) { 508 unsigned long bt = lr->backtrace[q]; 509 510 if (!bt) 511 break; 512 seq_printf(m, " %ps", (void *)bt); 513 } 514 seq_putc(m, '\n'); 515 } 516 517 } 518 put_task_struct(task); 519 return 0; 520 } 521 522 static int lstats_open(struct inode *inode, struct file *file) 523 { 524 return single_open(file, lstats_show_proc, inode); 525 } 526 527 static ssize_t lstats_write(struct file *file, const char __user *buf, 528 size_t count, loff_t *offs) 529 { 530 struct task_struct *task = get_proc_task(file_inode(file)); 531 532 if (!task) 533 return -ESRCH; 534 clear_tsk_latency_tracing(task); 535 put_task_struct(task); 536 537 return count; 538 } 539 540 static const struct file_operations proc_lstats_operations = { 541 .open = lstats_open, 542 .read = seq_read, 543 .write = lstats_write, 544 .llseek = seq_lseek, 545 .release = single_release, 546 }; 547 548 #endif 549 550 static int proc_oom_score(struct seq_file *m, struct pid_namespace *ns, 551 struct pid *pid, struct task_struct *task) 552 { 553 unsigned long totalpages = totalram_pages() + total_swap_pages; 554 unsigned long points = 0; 555 long badness; 556 557 badness = oom_badness(task, totalpages); 558 /* 559 * Special case OOM_SCORE_ADJ_MIN for all others scale the 560 * badness value into [0, 2000] range which we have been 561 * exporting for a long time so userspace might depend on it. 562 */ 563 if (badness != LONG_MIN) 564 points = (1000 + badness * 1000 / (long)totalpages) * 2 / 3; 565 566 seq_printf(m, "%lu\n", points); 567 568 return 0; 569 } 570 571 struct limit_names { 572 const char *name; 573 const char *unit; 574 }; 575 576 static const struct limit_names lnames[RLIM_NLIMITS] = { 577 [RLIMIT_CPU] = {"Max cpu time", "seconds"}, 578 [RLIMIT_FSIZE] = {"Max file size", "bytes"}, 579 [RLIMIT_DATA] = {"Max data size", "bytes"}, 580 [RLIMIT_STACK] = {"Max stack size", "bytes"}, 581 [RLIMIT_CORE] = {"Max core file size", "bytes"}, 582 [RLIMIT_RSS] = {"Max resident set", "bytes"}, 583 [RLIMIT_NPROC] = {"Max processes", "processes"}, 584 [RLIMIT_NOFILE] = {"Max open files", "files"}, 585 [RLIMIT_MEMLOCK] = {"Max locked memory", "bytes"}, 586 [RLIMIT_AS] = {"Max address space", "bytes"}, 587 [RLIMIT_LOCKS] = {"Max file locks", "locks"}, 588 [RLIMIT_SIGPENDING] = {"Max pending signals", "signals"}, 589 [RLIMIT_MSGQUEUE] = {"Max msgqueue size", "bytes"}, 590 [RLIMIT_NICE] = {"Max nice priority", NULL}, 591 [RLIMIT_RTPRIO] = {"Max realtime priority", NULL}, 592 [RLIMIT_RTTIME] = {"Max realtime timeout", "us"}, 593 }; 594 595 /* Display limits for a process */ 596 static int proc_pid_limits(struct seq_file *m, struct pid_namespace *ns, 597 struct pid *pid, struct task_struct *task) 598 { 599 unsigned int i; 600 unsigned long flags; 601 602 struct rlimit rlim[RLIM_NLIMITS]; 603 604 if (!lock_task_sighand(task, &flags)) 605 return 0; 606 memcpy(rlim, task->signal->rlim, sizeof(struct rlimit) * RLIM_NLIMITS); 607 unlock_task_sighand(task, &flags); 608 609 /* 610 * print the file header 611 */ 612 seq_puts(m, "Limit " 613 "Soft Limit " 614 "Hard Limit " 615 "Units \n"); 616 617 for (i = 0; i < RLIM_NLIMITS; i++) { 618 if (rlim[i].rlim_cur == RLIM_INFINITY) 619 seq_printf(m, "%-25s %-20s ", 620 lnames[i].name, "unlimited"); 621 else 622 seq_printf(m, "%-25s %-20lu ", 623 lnames[i].name, rlim[i].rlim_cur); 624 625 if (rlim[i].rlim_max == RLIM_INFINITY) 626 seq_printf(m, "%-20s ", "unlimited"); 627 else 628 seq_printf(m, "%-20lu ", rlim[i].rlim_max); 629 630 if (lnames[i].unit) 631 seq_printf(m, "%-10s\n", lnames[i].unit); 632 else 633 seq_putc(m, '\n'); 634 } 635 636 return 0; 637 } 638 639 #ifdef CONFIG_HAVE_ARCH_TRACEHOOK 640 static int proc_pid_syscall(struct seq_file *m, struct pid_namespace *ns, 641 struct pid *pid, struct task_struct *task) 642 { 643 struct syscall_info info; 644 u64 *args = &info.data.args[0]; 645 int res; 646 647 res = lock_trace(task); 648 if (res) 649 return res; 650 651 if (task_current_syscall(task, &info)) 652 seq_puts(m, "running\n"); 653 else if (info.data.nr < 0) 654 seq_printf(m, "%d 0x%llx 0x%llx\n", 655 info.data.nr, info.sp, info.data.instruction_pointer); 656 else 657 seq_printf(m, 658 "%d 0x%llx 0x%llx 0x%llx 0x%llx 0x%llx 0x%llx 0x%llx 0x%llx\n", 659 info.data.nr, 660 args[0], args[1], args[2], args[3], args[4], args[5], 661 info.sp, info.data.instruction_pointer); 662 unlock_trace(task); 663 664 return 0; 665 } 666 #endif /* CONFIG_HAVE_ARCH_TRACEHOOK */ 667 668 /************************************************************************/ 669 /* Here the fs part begins */ 670 /************************************************************************/ 671 672 /* permission checks */ 673 static bool proc_fd_access_allowed(struct inode *inode) 674 { 675 struct task_struct *task; 676 bool allowed = false; 677 /* Allow access to a task's file descriptors if it is us or we 678 * may use ptrace attach to the process and find out that 679 * information. 680 */ 681 task = get_proc_task(inode); 682 if (task) { 683 allowed = ptrace_may_access(task, PTRACE_MODE_READ_FSCREDS); 684 put_task_struct(task); 685 } 686 return allowed; 687 } 688 689 int proc_setattr(struct mnt_idmap *idmap, struct dentry *dentry, 690 struct iattr *attr) 691 { 692 int error; 693 struct inode *inode = d_inode(dentry); 694 695 if (attr->ia_valid & ATTR_MODE) 696 return -EPERM; 697 698 error = setattr_prepare(&nop_mnt_idmap, dentry, attr); 699 if (error) 700 return error; 701 702 setattr_copy(&nop_mnt_idmap, inode, attr); 703 return 0; 704 } 705 706 /* 707 * May current process learn task's sched/cmdline info (for hide_pid_min=1) 708 * or euid/egid (for hide_pid_min=2)? 709 */ 710 static bool has_pid_permissions(struct proc_fs_info *fs_info, 711 struct task_struct *task, 712 enum proc_hidepid hide_pid_min) 713 { 714 /* 715 * If 'hidpid' mount option is set force a ptrace check, 716 * we indicate that we are using a filesystem syscall 717 * by passing PTRACE_MODE_READ_FSCREDS 718 */ 719 if (fs_info->hide_pid == HIDEPID_NOT_PTRACEABLE) 720 return ptrace_may_access(task, PTRACE_MODE_READ_FSCREDS); 721 722 if (fs_info->hide_pid < hide_pid_min) 723 return true; 724 if (in_group_p(fs_info->pid_gid)) 725 return true; 726 return ptrace_may_access(task, PTRACE_MODE_READ_FSCREDS); 727 } 728 729 730 static int proc_pid_permission(struct mnt_idmap *idmap, 731 struct inode *inode, int mask) 732 { 733 struct proc_fs_info *fs_info = proc_sb_info(inode->i_sb); 734 struct task_struct *task; 735 bool has_perms; 736 737 task = get_proc_task(inode); 738 if (!task) 739 return -ESRCH; 740 has_perms = has_pid_permissions(fs_info, task, HIDEPID_NO_ACCESS); 741 put_task_struct(task); 742 743 if (!has_perms) { 744 if (fs_info->hide_pid == HIDEPID_INVISIBLE) { 745 /* 746 * Let's make getdents(), stat(), and open() 747 * consistent with each other. If a process 748 * may not stat() a file, it shouldn't be seen 749 * in procfs at all. 750 */ 751 return -ENOENT; 752 } 753 754 return -EPERM; 755 } 756 return generic_permission(&nop_mnt_idmap, inode, mask); 757 } 758 759 760 761 static const struct inode_operations proc_def_inode_operations = { 762 .setattr = proc_setattr, 763 }; 764 765 static int proc_single_show(struct seq_file *m, void *v) 766 { 767 struct inode *inode = m->private; 768 struct pid_namespace *ns = proc_pid_ns(inode->i_sb); 769 struct pid *pid = proc_pid(inode); 770 struct task_struct *task; 771 int ret; 772 773 task = get_pid_task(pid, PIDTYPE_PID); 774 if (!task) 775 return -ESRCH; 776 777 ret = PROC_I(inode)->op.proc_show(m, ns, pid, task); 778 779 put_task_struct(task); 780 return ret; 781 } 782 783 static int proc_single_open(struct inode *inode, struct file *filp) 784 { 785 return single_open(filp, proc_single_show, inode); 786 } 787 788 static const struct file_operations proc_single_file_operations = { 789 .open = proc_single_open, 790 .read = seq_read, 791 .llseek = seq_lseek, 792 .release = single_release, 793 }; 794 795 796 struct mm_struct *proc_mem_open(struct inode *inode, unsigned int mode) 797 { 798 struct task_struct *task = get_proc_task(inode); 799 struct mm_struct *mm = ERR_PTR(-ESRCH); 800 801 if (task) { 802 mm = mm_access(task, mode | PTRACE_MODE_FSCREDS); 803 put_task_struct(task); 804 805 if (!IS_ERR_OR_NULL(mm)) { 806 /* ensure this mm_struct can't be freed */ 807 mmgrab(mm); 808 /* but do not pin its memory */ 809 mmput(mm); 810 } 811 } 812 813 return mm; 814 } 815 816 static int __mem_open(struct inode *inode, struct file *file, unsigned int mode) 817 { 818 struct mm_struct *mm = proc_mem_open(inode, mode); 819 820 if (IS_ERR(mm)) 821 return PTR_ERR(mm); 822 823 file->private_data = mm; 824 return 0; 825 } 826 827 static int mem_open(struct inode *inode, struct file *file) 828 { 829 int ret = __mem_open(inode, file, PTRACE_MODE_ATTACH); 830 831 /* OK to pass negative loff_t, we can catch out-of-range */ 832 file->f_mode |= FMODE_UNSIGNED_OFFSET; 833 834 return ret; 835 } 836 837 static ssize_t mem_rw(struct file *file, char __user *buf, 838 size_t count, loff_t *ppos, int write) 839 { 840 struct mm_struct *mm = file->private_data; 841 unsigned long addr = *ppos; 842 ssize_t copied; 843 char *page; 844 unsigned int flags; 845 846 if (!mm) 847 return 0; 848 849 page = (char *)__get_free_page(GFP_KERNEL); 850 if (!page) 851 return -ENOMEM; 852 853 copied = 0; 854 if (!mmget_not_zero(mm)) 855 goto free; 856 857 flags = FOLL_FORCE | (write ? FOLL_WRITE : 0); 858 859 while (count > 0) { 860 size_t this_len = min_t(size_t, count, PAGE_SIZE); 861 862 if (write && copy_from_user(page, buf, this_len)) { 863 copied = -EFAULT; 864 break; 865 } 866 867 this_len = access_remote_vm(mm, addr, page, this_len, flags); 868 if (!this_len) { 869 if (!copied) 870 copied = -EIO; 871 break; 872 } 873 874 if (!write && copy_to_user(buf, page, this_len)) { 875 copied = -EFAULT; 876 break; 877 } 878 879 buf += this_len; 880 addr += this_len; 881 copied += this_len; 882 count -= this_len; 883 } 884 *ppos = addr; 885 886 mmput(mm); 887 free: 888 free_page((unsigned long) page); 889 return copied; 890 } 891 892 static ssize_t mem_read(struct file *file, char __user *buf, 893 size_t count, loff_t *ppos) 894 { 895 return mem_rw(file, buf, count, ppos, 0); 896 } 897 898 static ssize_t mem_write(struct file *file, const char __user *buf, 899 size_t count, loff_t *ppos) 900 { 901 return mem_rw(file, (char __user*)buf, count, ppos, 1); 902 } 903 904 loff_t mem_lseek(struct file *file, loff_t offset, int orig) 905 { 906 switch (orig) { 907 case 0: 908 file->f_pos = offset; 909 break; 910 case 1: 911 file->f_pos += offset; 912 break; 913 default: 914 return -EINVAL; 915 } 916 force_successful_syscall_return(); 917 return file->f_pos; 918 } 919 920 static int mem_release(struct inode *inode, struct file *file) 921 { 922 struct mm_struct *mm = file->private_data; 923 if (mm) 924 mmdrop(mm); 925 return 0; 926 } 927 928 static const struct file_operations proc_mem_operations = { 929 .llseek = mem_lseek, 930 .read = mem_read, 931 .write = mem_write, 932 .open = mem_open, 933 .release = mem_release, 934 }; 935 936 static int environ_open(struct inode *inode, struct file *file) 937 { 938 return __mem_open(inode, file, PTRACE_MODE_READ); 939 } 940 941 static ssize_t environ_read(struct file *file, char __user *buf, 942 size_t count, loff_t *ppos) 943 { 944 char *page; 945 unsigned long src = *ppos; 946 int ret = 0; 947 struct mm_struct *mm = file->private_data; 948 unsigned long env_start, env_end; 949 950 /* Ensure the process spawned far enough to have an environment. */ 951 if (!mm || !mm->env_end) 952 return 0; 953 954 page = (char *)__get_free_page(GFP_KERNEL); 955 if (!page) 956 return -ENOMEM; 957 958 ret = 0; 959 if (!mmget_not_zero(mm)) 960 goto free; 961 962 spin_lock(&mm->arg_lock); 963 env_start = mm->env_start; 964 env_end = mm->env_end; 965 spin_unlock(&mm->arg_lock); 966 967 while (count > 0) { 968 size_t this_len, max_len; 969 int retval; 970 971 if (src >= (env_end - env_start)) 972 break; 973 974 this_len = env_end - (env_start + src); 975 976 max_len = min_t(size_t, PAGE_SIZE, count); 977 this_len = min(max_len, this_len); 978 979 retval = access_remote_vm(mm, (env_start + src), page, this_len, FOLL_ANON); 980 981 if (retval <= 0) { 982 ret = retval; 983 break; 984 } 985 986 if (copy_to_user(buf, page, retval)) { 987 ret = -EFAULT; 988 break; 989 } 990 991 ret += retval; 992 src += retval; 993 buf += retval; 994 count -= retval; 995 } 996 *ppos = src; 997 mmput(mm); 998 999 free: 1000 free_page((unsigned long) page); 1001 return ret; 1002 } 1003 1004 static const struct file_operations proc_environ_operations = { 1005 .open = environ_open, 1006 .read = environ_read, 1007 .llseek = generic_file_llseek, 1008 .release = mem_release, 1009 }; 1010 1011 static int auxv_open(struct inode *inode, struct file *file) 1012 { 1013 return __mem_open(inode, file, PTRACE_MODE_READ_FSCREDS); 1014 } 1015 1016 static ssize_t auxv_read(struct file *file, char __user *buf, 1017 size_t count, loff_t *ppos) 1018 { 1019 struct mm_struct *mm = file->private_data; 1020 unsigned int nwords = 0; 1021 1022 if (!mm) 1023 return 0; 1024 do { 1025 nwords += 2; 1026 } while (mm->saved_auxv[nwords - 2] != 0); /* AT_NULL */ 1027 return simple_read_from_buffer(buf, count, ppos, mm->saved_auxv, 1028 nwords * sizeof(mm->saved_auxv[0])); 1029 } 1030 1031 static const struct file_operations proc_auxv_operations = { 1032 .open = auxv_open, 1033 .read = auxv_read, 1034 .llseek = generic_file_llseek, 1035 .release = mem_release, 1036 }; 1037 1038 static ssize_t oom_adj_read(struct file *file, char __user *buf, size_t count, 1039 loff_t *ppos) 1040 { 1041 struct task_struct *task = get_proc_task(file_inode(file)); 1042 char buffer[PROC_NUMBUF]; 1043 int oom_adj = OOM_ADJUST_MIN; 1044 size_t len; 1045 1046 if (!task) 1047 return -ESRCH; 1048 if (task->signal->oom_score_adj == OOM_SCORE_ADJ_MAX) 1049 oom_adj = OOM_ADJUST_MAX; 1050 else 1051 oom_adj = (task->signal->oom_score_adj * -OOM_DISABLE) / 1052 OOM_SCORE_ADJ_MAX; 1053 put_task_struct(task); 1054 if (oom_adj > OOM_ADJUST_MAX) 1055 oom_adj = OOM_ADJUST_MAX; 1056 len = snprintf(buffer, sizeof(buffer), "%d\n", oom_adj); 1057 return simple_read_from_buffer(buf, count, ppos, buffer, len); 1058 } 1059 1060 static int __set_oom_adj(struct file *file, int oom_adj, bool legacy) 1061 { 1062 struct mm_struct *mm = NULL; 1063 struct task_struct *task; 1064 int err = 0; 1065 1066 task = get_proc_task(file_inode(file)); 1067 if (!task) 1068 return -ESRCH; 1069 1070 mutex_lock(&oom_adj_mutex); 1071 if (legacy) { 1072 if (oom_adj < task->signal->oom_score_adj && 1073 !capable(CAP_SYS_RESOURCE)) { 1074 err = -EACCES; 1075 goto err_unlock; 1076 } 1077 /* 1078 * /proc/pid/oom_adj is provided for legacy purposes, ask users to use 1079 * /proc/pid/oom_score_adj instead. 1080 */ 1081 pr_warn_once("%s (%d): /proc/%d/oom_adj is deprecated, please use /proc/%d/oom_score_adj instead.\n", 1082 current->comm, task_pid_nr(current), task_pid_nr(task), 1083 task_pid_nr(task)); 1084 } else { 1085 if ((short)oom_adj < task->signal->oom_score_adj_min && 1086 !capable(CAP_SYS_RESOURCE)) { 1087 err = -EACCES; 1088 goto err_unlock; 1089 } 1090 } 1091 1092 /* 1093 * Make sure we will check other processes sharing the mm if this is 1094 * not vfrok which wants its own oom_score_adj. 1095 * pin the mm so it doesn't go away and get reused after task_unlock 1096 */ 1097 if (!task->vfork_done) { 1098 struct task_struct *p = find_lock_task_mm(task); 1099 1100 if (p) { 1101 if (test_bit(MMF_MULTIPROCESS, &p->mm->flags)) { 1102 mm = p->mm; 1103 mmgrab(mm); 1104 } 1105 task_unlock(p); 1106 } 1107 } 1108 1109 task->signal->oom_score_adj = oom_adj; 1110 if (!legacy && has_capability_noaudit(current, CAP_SYS_RESOURCE)) 1111 task->signal->oom_score_adj_min = (short)oom_adj; 1112 trace_oom_score_adj_update(task); 1113 1114 if (mm) { 1115 struct task_struct *p; 1116 1117 rcu_read_lock(); 1118 for_each_process(p) { 1119 if (same_thread_group(task, p)) 1120 continue; 1121 1122 /* do not touch kernel threads or the global init */ 1123 if (p->flags & PF_KTHREAD || is_global_init(p)) 1124 continue; 1125 1126 task_lock(p); 1127 if (!p->vfork_done && process_shares_mm(p, mm)) { 1128 p->signal->oom_score_adj = oom_adj; 1129 if (!legacy && has_capability_noaudit(current, CAP_SYS_RESOURCE)) 1130 p->signal->oom_score_adj_min = (short)oom_adj; 1131 } 1132 task_unlock(p); 1133 } 1134 rcu_read_unlock(); 1135 mmdrop(mm); 1136 } 1137 err_unlock: 1138 mutex_unlock(&oom_adj_mutex); 1139 put_task_struct(task); 1140 return err; 1141 } 1142 1143 /* 1144 * /proc/pid/oom_adj exists solely for backwards compatibility with previous 1145 * kernels. The effective policy is defined by oom_score_adj, which has a 1146 * different scale: oom_adj grew exponentially and oom_score_adj grows linearly. 1147 * Values written to oom_adj are simply mapped linearly to oom_score_adj. 1148 * Processes that become oom disabled via oom_adj will still be oom disabled 1149 * with this implementation. 1150 * 1151 * oom_adj cannot be removed since existing userspace binaries use it. 1152 */ 1153 static ssize_t oom_adj_write(struct file *file, const char __user *buf, 1154 size_t count, loff_t *ppos) 1155 { 1156 char buffer[PROC_NUMBUF] = {}; 1157 int oom_adj; 1158 int err; 1159 1160 if (count > sizeof(buffer) - 1) 1161 count = sizeof(buffer) - 1; 1162 if (copy_from_user(buffer, buf, count)) { 1163 err = -EFAULT; 1164 goto out; 1165 } 1166 1167 err = kstrtoint(strstrip(buffer), 0, &oom_adj); 1168 if (err) 1169 goto out; 1170 if ((oom_adj < OOM_ADJUST_MIN || oom_adj > OOM_ADJUST_MAX) && 1171 oom_adj != OOM_DISABLE) { 1172 err = -EINVAL; 1173 goto out; 1174 } 1175 1176 /* 1177 * Scale /proc/pid/oom_score_adj appropriately ensuring that a maximum 1178 * value is always attainable. 1179 */ 1180 if (oom_adj == OOM_ADJUST_MAX) 1181 oom_adj = OOM_SCORE_ADJ_MAX; 1182 else 1183 oom_adj = (oom_adj * OOM_SCORE_ADJ_MAX) / -OOM_DISABLE; 1184 1185 err = __set_oom_adj(file, oom_adj, true); 1186 out: 1187 return err < 0 ? err : count; 1188 } 1189 1190 static const struct file_operations proc_oom_adj_operations = { 1191 .read = oom_adj_read, 1192 .write = oom_adj_write, 1193 .llseek = generic_file_llseek, 1194 }; 1195 1196 static ssize_t oom_score_adj_read(struct file *file, char __user *buf, 1197 size_t count, loff_t *ppos) 1198 { 1199 struct task_struct *task = get_proc_task(file_inode(file)); 1200 char buffer[PROC_NUMBUF]; 1201 short oom_score_adj = OOM_SCORE_ADJ_MIN; 1202 size_t len; 1203 1204 if (!task) 1205 return -ESRCH; 1206 oom_score_adj = task->signal->oom_score_adj; 1207 put_task_struct(task); 1208 len = snprintf(buffer, sizeof(buffer), "%hd\n", oom_score_adj); 1209 return simple_read_from_buffer(buf, count, ppos, buffer, len); 1210 } 1211 1212 static ssize_t oom_score_adj_write(struct file *file, const char __user *buf, 1213 size_t count, loff_t *ppos) 1214 { 1215 char buffer[PROC_NUMBUF] = {}; 1216 int oom_score_adj; 1217 int err; 1218 1219 if (count > sizeof(buffer) - 1) 1220 count = sizeof(buffer) - 1; 1221 if (copy_from_user(buffer, buf, count)) { 1222 err = -EFAULT; 1223 goto out; 1224 } 1225 1226 err = kstrtoint(strstrip(buffer), 0, &oom_score_adj); 1227 if (err) 1228 goto out; 1229 if (oom_score_adj < OOM_SCORE_ADJ_MIN || 1230 oom_score_adj > OOM_SCORE_ADJ_MAX) { 1231 err = -EINVAL; 1232 goto out; 1233 } 1234 1235 err = __set_oom_adj(file, oom_score_adj, false); 1236 out: 1237 return err < 0 ? err : count; 1238 } 1239 1240 static const struct file_operations proc_oom_score_adj_operations = { 1241 .read = oom_score_adj_read, 1242 .write = oom_score_adj_write, 1243 .llseek = default_llseek, 1244 }; 1245 1246 #ifdef CONFIG_AUDIT 1247 #define TMPBUFLEN 11 1248 static ssize_t proc_loginuid_read(struct file * file, char __user * buf, 1249 size_t count, loff_t *ppos) 1250 { 1251 struct inode * inode = file_inode(file); 1252 struct task_struct *task = get_proc_task(inode); 1253 ssize_t length; 1254 char tmpbuf[TMPBUFLEN]; 1255 1256 if (!task) 1257 return -ESRCH; 1258 length = scnprintf(tmpbuf, TMPBUFLEN, "%u", 1259 from_kuid(file->f_cred->user_ns, 1260 audit_get_loginuid(task))); 1261 put_task_struct(task); 1262 return simple_read_from_buffer(buf, count, ppos, tmpbuf, length); 1263 } 1264 1265 static ssize_t proc_loginuid_write(struct file * file, const char __user * buf, 1266 size_t count, loff_t *ppos) 1267 { 1268 struct inode * inode = file_inode(file); 1269 uid_t loginuid; 1270 kuid_t kloginuid; 1271 int rv; 1272 1273 /* Don't let kthreads write their own loginuid */ 1274 if (current->flags & PF_KTHREAD) 1275 return -EPERM; 1276 1277 rcu_read_lock(); 1278 if (current != pid_task(proc_pid(inode), PIDTYPE_PID)) { 1279 rcu_read_unlock(); 1280 return -EPERM; 1281 } 1282 rcu_read_unlock(); 1283 1284 if (*ppos != 0) { 1285 /* No partial writes. */ 1286 return -EINVAL; 1287 } 1288 1289 rv = kstrtou32_from_user(buf, count, 10, &loginuid); 1290 if (rv < 0) 1291 return rv; 1292 1293 /* is userspace tring to explicitly UNSET the loginuid? */ 1294 if (loginuid == AUDIT_UID_UNSET) { 1295 kloginuid = INVALID_UID; 1296 } else { 1297 kloginuid = make_kuid(file->f_cred->user_ns, loginuid); 1298 if (!uid_valid(kloginuid)) 1299 return -EINVAL; 1300 } 1301 1302 rv = audit_set_loginuid(kloginuid); 1303 if (rv < 0) 1304 return rv; 1305 return count; 1306 } 1307 1308 static const struct file_operations proc_loginuid_operations = { 1309 .read = proc_loginuid_read, 1310 .write = proc_loginuid_write, 1311 .llseek = generic_file_llseek, 1312 }; 1313 1314 static ssize_t proc_sessionid_read(struct file * file, char __user * buf, 1315 size_t count, loff_t *ppos) 1316 { 1317 struct inode * inode = file_inode(file); 1318 struct task_struct *task = get_proc_task(inode); 1319 ssize_t length; 1320 char tmpbuf[TMPBUFLEN]; 1321 1322 if (!task) 1323 return -ESRCH; 1324 length = scnprintf(tmpbuf, TMPBUFLEN, "%u", 1325 audit_get_sessionid(task)); 1326 put_task_struct(task); 1327 return simple_read_from_buffer(buf, count, ppos, tmpbuf, length); 1328 } 1329 1330 static const struct file_operations proc_sessionid_operations = { 1331 .read = proc_sessionid_read, 1332 .llseek = generic_file_llseek, 1333 }; 1334 #endif 1335 1336 #ifdef CONFIG_FAULT_INJECTION 1337 static ssize_t proc_fault_inject_read(struct file * file, char __user * buf, 1338 size_t count, loff_t *ppos) 1339 { 1340 struct task_struct *task = get_proc_task(file_inode(file)); 1341 char buffer[PROC_NUMBUF]; 1342 size_t len; 1343 int make_it_fail; 1344 1345 if (!task) 1346 return -ESRCH; 1347 make_it_fail = task->make_it_fail; 1348 put_task_struct(task); 1349 1350 len = snprintf(buffer, sizeof(buffer), "%i\n", make_it_fail); 1351 1352 return simple_read_from_buffer(buf, count, ppos, buffer, len); 1353 } 1354 1355 static ssize_t proc_fault_inject_write(struct file * file, 1356 const char __user * buf, size_t count, loff_t *ppos) 1357 { 1358 struct task_struct *task; 1359 char buffer[PROC_NUMBUF] = {}; 1360 int make_it_fail; 1361 int rv; 1362 1363 if (!capable(CAP_SYS_RESOURCE)) 1364 return -EPERM; 1365 1366 if (count > sizeof(buffer) - 1) 1367 count = sizeof(buffer) - 1; 1368 if (copy_from_user(buffer, buf, count)) 1369 return -EFAULT; 1370 rv = kstrtoint(strstrip(buffer), 0, &make_it_fail); 1371 if (rv < 0) 1372 return rv; 1373 if (make_it_fail < 0 || make_it_fail > 1) 1374 return -EINVAL; 1375 1376 task = get_proc_task(file_inode(file)); 1377 if (!task) 1378 return -ESRCH; 1379 task->make_it_fail = make_it_fail; 1380 put_task_struct(task); 1381 1382 return count; 1383 } 1384 1385 static const struct file_operations proc_fault_inject_operations = { 1386 .read = proc_fault_inject_read, 1387 .write = proc_fault_inject_write, 1388 .llseek = generic_file_llseek, 1389 }; 1390 1391 static ssize_t proc_fail_nth_write(struct file *file, const char __user *buf, 1392 size_t count, loff_t *ppos) 1393 { 1394 struct task_struct *task; 1395 int err; 1396 unsigned int n; 1397 1398 err = kstrtouint_from_user(buf, count, 0, &n); 1399 if (err) 1400 return err; 1401 1402 task = get_proc_task(file_inode(file)); 1403 if (!task) 1404 return -ESRCH; 1405 task->fail_nth = n; 1406 put_task_struct(task); 1407 1408 return count; 1409 } 1410 1411 static ssize_t proc_fail_nth_read(struct file *file, char __user *buf, 1412 size_t count, loff_t *ppos) 1413 { 1414 struct task_struct *task; 1415 char numbuf[PROC_NUMBUF]; 1416 ssize_t len; 1417 1418 task = get_proc_task(file_inode(file)); 1419 if (!task) 1420 return -ESRCH; 1421 len = snprintf(numbuf, sizeof(numbuf), "%u\n", task->fail_nth); 1422 put_task_struct(task); 1423 return simple_read_from_buffer(buf, count, ppos, numbuf, len); 1424 } 1425 1426 static const struct file_operations proc_fail_nth_operations = { 1427 .read = proc_fail_nth_read, 1428 .write = proc_fail_nth_write, 1429 }; 1430 #endif 1431 1432 1433 #ifdef CONFIG_SCHED_DEBUG 1434 /* 1435 * Print out various scheduling related per-task fields: 1436 */ 1437 static int sched_show(struct seq_file *m, void *v) 1438 { 1439 struct inode *inode = m->private; 1440 struct pid_namespace *ns = proc_pid_ns(inode->i_sb); 1441 struct task_struct *p; 1442 1443 p = get_proc_task(inode); 1444 if (!p) 1445 return -ESRCH; 1446 proc_sched_show_task(p, ns, m); 1447 1448 put_task_struct(p); 1449 1450 return 0; 1451 } 1452 1453 static ssize_t 1454 sched_write(struct file *file, const char __user *buf, 1455 size_t count, loff_t *offset) 1456 { 1457 struct inode *inode = file_inode(file); 1458 struct task_struct *p; 1459 1460 p = get_proc_task(inode); 1461 if (!p) 1462 return -ESRCH; 1463 proc_sched_set_task(p); 1464 1465 put_task_struct(p); 1466 1467 return count; 1468 } 1469 1470 static int sched_open(struct inode *inode, struct file *filp) 1471 { 1472 return single_open(filp, sched_show, inode); 1473 } 1474 1475 static const struct file_operations proc_pid_sched_operations = { 1476 .open = sched_open, 1477 .read = seq_read, 1478 .write = sched_write, 1479 .llseek = seq_lseek, 1480 .release = single_release, 1481 }; 1482 1483 #endif 1484 1485 #ifdef CONFIG_SCHED_AUTOGROUP 1486 /* 1487 * Print out autogroup related information: 1488 */ 1489 static int sched_autogroup_show(struct seq_file *m, void *v) 1490 { 1491 struct inode *inode = m->private; 1492 struct task_struct *p; 1493 1494 p = get_proc_task(inode); 1495 if (!p) 1496 return -ESRCH; 1497 proc_sched_autogroup_show_task(p, m); 1498 1499 put_task_struct(p); 1500 1501 return 0; 1502 } 1503 1504 static ssize_t 1505 sched_autogroup_write(struct file *file, const char __user *buf, 1506 size_t count, loff_t *offset) 1507 { 1508 struct inode *inode = file_inode(file); 1509 struct task_struct *p; 1510 char buffer[PROC_NUMBUF] = {}; 1511 int nice; 1512 int err; 1513 1514 if (count > sizeof(buffer) - 1) 1515 count = sizeof(buffer) - 1; 1516 if (copy_from_user(buffer, buf, count)) 1517 return -EFAULT; 1518 1519 err = kstrtoint(strstrip(buffer), 0, &nice); 1520 if (err < 0) 1521 return err; 1522 1523 p = get_proc_task(inode); 1524 if (!p) 1525 return -ESRCH; 1526 1527 err = proc_sched_autogroup_set_nice(p, nice); 1528 if (err) 1529 count = err; 1530 1531 put_task_struct(p); 1532 1533 return count; 1534 } 1535 1536 static int sched_autogroup_open(struct inode *inode, struct file *filp) 1537 { 1538 int ret; 1539 1540 ret = single_open(filp, sched_autogroup_show, NULL); 1541 if (!ret) { 1542 struct seq_file *m = filp->private_data; 1543 1544 m->private = inode; 1545 } 1546 return ret; 1547 } 1548 1549 static const struct file_operations proc_pid_sched_autogroup_operations = { 1550 .open = sched_autogroup_open, 1551 .read = seq_read, 1552 .write = sched_autogroup_write, 1553 .llseek = seq_lseek, 1554 .release = single_release, 1555 }; 1556 1557 #endif /* CONFIG_SCHED_AUTOGROUP */ 1558 1559 #ifdef CONFIG_TIME_NS 1560 static int timens_offsets_show(struct seq_file *m, void *v) 1561 { 1562 struct task_struct *p; 1563 1564 p = get_proc_task(file_inode(m->file)); 1565 if (!p) 1566 return -ESRCH; 1567 proc_timens_show_offsets(p, m); 1568 1569 put_task_struct(p); 1570 1571 return 0; 1572 } 1573 1574 static ssize_t timens_offsets_write(struct file *file, const char __user *buf, 1575 size_t count, loff_t *ppos) 1576 { 1577 struct inode *inode = file_inode(file); 1578 struct proc_timens_offset offsets[2]; 1579 char *kbuf = NULL, *pos, *next_line; 1580 struct task_struct *p; 1581 int ret, noffsets; 1582 1583 /* Only allow < page size writes at the beginning of the file */ 1584 if ((*ppos != 0) || (count >= PAGE_SIZE)) 1585 return -EINVAL; 1586 1587 /* Slurp in the user data */ 1588 kbuf = memdup_user_nul(buf, count); 1589 if (IS_ERR(kbuf)) 1590 return PTR_ERR(kbuf); 1591 1592 /* Parse the user data */ 1593 ret = -EINVAL; 1594 noffsets = 0; 1595 for (pos = kbuf; pos; pos = next_line) { 1596 struct proc_timens_offset *off = &offsets[noffsets]; 1597 char clock[10]; 1598 int err; 1599 1600 /* Find the end of line and ensure we don't look past it */ 1601 next_line = strchr(pos, '\n'); 1602 if (next_line) { 1603 *next_line = '\0'; 1604 next_line++; 1605 if (*next_line == '\0') 1606 next_line = NULL; 1607 } 1608 1609 err = sscanf(pos, "%9s %lld %lu", clock, 1610 &off->val.tv_sec, &off->val.tv_nsec); 1611 if (err != 3 || off->val.tv_nsec >= NSEC_PER_SEC) 1612 goto out; 1613 1614 clock[sizeof(clock) - 1] = 0; 1615 if (strcmp(clock, "monotonic") == 0 || 1616 strcmp(clock, __stringify(CLOCK_MONOTONIC)) == 0) 1617 off->clockid = CLOCK_MONOTONIC; 1618 else if (strcmp(clock, "boottime") == 0 || 1619 strcmp(clock, __stringify(CLOCK_BOOTTIME)) == 0) 1620 off->clockid = CLOCK_BOOTTIME; 1621 else 1622 goto out; 1623 1624 noffsets++; 1625 if (noffsets == ARRAY_SIZE(offsets)) { 1626 if (next_line) 1627 count = next_line - kbuf; 1628 break; 1629 } 1630 } 1631 1632 ret = -ESRCH; 1633 p = get_proc_task(inode); 1634 if (!p) 1635 goto out; 1636 ret = proc_timens_set_offset(file, p, offsets, noffsets); 1637 put_task_struct(p); 1638 if (ret) 1639 goto out; 1640 1641 ret = count; 1642 out: 1643 kfree(kbuf); 1644 return ret; 1645 } 1646 1647 static int timens_offsets_open(struct inode *inode, struct file *filp) 1648 { 1649 return single_open(filp, timens_offsets_show, inode); 1650 } 1651 1652 static const struct file_operations proc_timens_offsets_operations = { 1653 .open = timens_offsets_open, 1654 .read = seq_read, 1655 .write = timens_offsets_write, 1656 .llseek = seq_lseek, 1657 .release = single_release, 1658 }; 1659 #endif /* CONFIG_TIME_NS */ 1660 1661 static ssize_t comm_write(struct file *file, const char __user *buf, 1662 size_t count, loff_t *offset) 1663 { 1664 struct inode *inode = file_inode(file); 1665 struct task_struct *p; 1666 char buffer[TASK_COMM_LEN] = {}; 1667 const size_t maxlen = sizeof(buffer) - 1; 1668 1669 if (copy_from_user(buffer, buf, count > maxlen ? maxlen : count)) 1670 return -EFAULT; 1671 1672 p = get_proc_task(inode); 1673 if (!p) 1674 return -ESRCH; 1675 1676 if (same_thread_group(current, p)) { 1677 set_task_comm(p, buffer); 1678 proc_comm_connector(p); 1679 } 1680 else 1681 count = -EINVAL; 1682 1683 put_task_struct(p); 1684 1685 return count; 1686 } 1687 1688 static int comm_show(struct seq_file *m, void *v) 1689 { 1690 struct inode *inode = m->private; 1691 struct task_struct *p; 1692 1693 p = get_proc_task(inode); 1694 if (!p) 1695 return -ESRCH; 1696 1697 proc_task_name(m, p, false); 1698 seq_putc(m, '\n'); 1699 1700 put_task_struct(p); 1701 1702 return 0; 1703 } 1704 1705 static int comm_open(struct inode *inode, struct file *filp) 1706 { 1707 return single_open(filp, comm_show, inode); 1708 } 1709 1710 static const struct file_operations proc_pid_set_comm_operations = { 1711 .open = comm_open, 1712 .read = seq_read, 1713 .write = comm_write, 1714 .llseek = seq_lseek, 1715 .release = single_release, 1716 }; 1717 1718 static int proc_exe_link(struct dentry *dentry, struct path *exe_path) 1719 { 1720 struct task_struct *task; 1721 struct file *exe_file; 1722 1723 task = get_proc_task(d_inode(dentry)); 1724 if (!task) 1725 return -ENOENT; 1726 exe_file = get_task_exe_file(task); 1727 put_task_struct(task); 1728 if (exe_file) { 1729 *exe_path = exe_file->f_path; 1730 path_get(&exe_file->f_path); 1731 fput(exe_file); 1732 return 0; 1733 } else 1734 return -ENOENT; 1735 } 1736 1737 static const char *proc_pid_get_link(struct dentry *dentry, 1738 struct inode *inode, 1739 struct delayed_call *done) 1740 { 1741 struct path path; 1742 int error = -EACCES; 1743 1744 if (!dentry) 1745 return ERR_PTR(-ECHILD); 1746 1747 /* Are we allowed to snoop on the tasks file descriptors? */ 1748 if (!proc_fd_access_allowed(inode)) 1749 goto out; 1750 1751 error = PROC_I(inode)->op.proc_get_link(dentry, &path); 1752 if (error) 1753 goto out; 1754 1755 error = nd_jump_link(&path); 1756 out: 1757 return ERR_PTR(error); 1758 } 1759 1760 static int do_proc_readlink(const struct path *path, char __user *buffer, int buflen) 1761 { 1762 char *tmp = kmalloc(PATH_MAX, GFP_KERNEL); 1763 char *pathname; 1764 int len; 1765 1766 if (!tmp) 1767 return -ENOMEM; 1768 1769 pathname = d_path(path, tmp, PATH_MAX); 1770 len = PTR_ERR(pathname); 1771 if (IS_ERR(pathname)) 1772 goto out; 1773 len = tmp + PATH_MAX - 1 - pathname; 1774 1775 if (len > buflen) 1776 len = buflen; 1777 if (copy_to_user(buffer, pathname, len)) 1778 len = -EFAULT; 1779 out: 1780 kfree(tmp); 1781 return len; 1782 } 1783 1784 static int proc_pid_readlink(struct dentry * dentry, char __user * buffer, int buflen) 1785 { 1786 int error = -EACCES; 1787 struct inode *inode = d_inode(dentry); 1788 struct path path; 1789 1790 /* Are we allowed to snoop on the tasks file descriptors? */ 1791 if (!proc_fd_access_allowed(inode)) 1792 goto out; 1793 1794 error = PROC_I(inode)->op.proc_get_link(dentry, &path); 1795 if (error) 1796 goto out; 1797 1798 error = do_proc_readlink(&path, buffer, buflen); 1799 path_put(&path); 1800 out: 1801 return error; 1802 } 1803 1804 const struct inode_operations proc_pid_link_inode_operations = { 1805 .readlink = proc_pid_readlink, 1806 .get_link = proc_pid_get_link, 1807 .setattr = proc_setattr, 1808 }; 1809 1810 1811 /* building an inode */ 1812 1813 void task_dump_owner(struct task_struct *task, umode_t mode, 1814 kuid_t *ruid, kgid_t *rgid) 1815 { 1816 /* Depending on the state of dumpable compute who should own a 1817 * proc file for a task. 1818 */ 1819 const struct cred *cred; 1820 kuid_t uid; 1821 kgid_t gid; 1822 1823 if (unlikely(task->flags & PF_KTHREAD)) { 1824 *ruid = GLOBAL_ROOT_UID; 1825 *rgid = GLOBAL_ROOT_GID; 1826 return; 1827 } 1828 1829 /* Default to the tasks effective ownership */ 1830 rcu_read_lock(); 1831 cred = __task_cred(task); 1832 uid = cred->euid; 1833 gid = cred->egid; 1834 rcu_read_unlock(); 1835 1836 /* 1837 * Before the /proc/pid/status file was created the only way to read 1838 * the effective uid of a /process was to stat /proc/pid. Reading 1839 * /proc/pid/status is slow enough that procps and other packages 1840 * kept stating /proc/pid. To keep the rules in /proc simple I have 1841 * made this apply to all per process world readable and executable 1842 * directories. 1843 */ 1844 if (mode != (S_IFDIR|S_IRUGO|S_IXUGO)) { 1845 struct mm_struct *mm; 1846 task_lock(task); 1847 mm = task->mm; 1848 /* Make non-dumpable tasks owned by some root */ 1849 if (mm) { 1850 if (get_dumpable(mm) != SUID_DUMP_USER) { 1851 struct user_namespace *user_ns = mm->user_ns; 1852 1853 uid = make_kuid(user_ns, 0); 1854 if (!uid_valid(uid)) 1855 uid = GLOBAL_ROOT_UID; 1856 1857 gid = make_kgid(user_ns, 0); 1858 if (!gid_valid(gid)) 1859 gid = GLOBAL_ROOT_GID; 1860 } 1861 } else { 1862 uid = GLOBAL_ROOT_UID; 1863 gid = GLOBAL_ROOT_GID; 1864 } 1865 task_unlock(task); 1866 } 1867 *ruid = uid; 1868 *rgid = gid; 1869 } 1870 1871 void proc_pid_evict_inode(struct proc_inode *ei) 1872 { 1873 struct pid *pid = ei->pid; 1874 1875 if (S_ISDIR(ei->vfs_inode.i_mode)) { 1876 spin_lock(&pid->lock); 1877 hlist_del_init_rcu(&ei->sibling_inodes); 1878 spin_unlock(&pid->lock); 1879 } 1880 1881 put_pid(pid); 1882 } 1883 1884 struct inode *proc_pid_make_inode(struct super_block *sb, 1885 struct task_struct *task, umode_t mode) 1886 { 1887 struct inode * inode; 1888 struct proc_inode *ei; 1889 struct pid *pid; 1890 1891 /* We need a new inode */ 1892 1893 inode = new_inode(sb); 1894 if (!inode) 1895 goto out; 1896 1897 /* Common stuff */ 1898 ei = PROC_I(inode); 1899 inode->i_mode = mode; 1900 inode->i_ino = get_next_ino(); 1901 simple_inode_init_ts(inode); 1902 inode->i_op = &proc_def_inode_operations; 1903 1904 /* 1905 * grab the reference to task. 1906 */ 1907 pid = get_task_pid(task, PIDTYPE_PID); 1908 if (!pid) 1909 goto out_unlock; 1910 1911 /* Let the pid remember us for quick removal */ 1912 ei->pid = pid; 1913 1914 task_dump_owner(task, 0, &inode->i_uid, &inode->i_gid); 1915 security_task_to_inode(task, inode); 1916 1917 out: 1918 return inode; 1919 1920 out_unlock: 1921 iput(inode); 1922 return NULL; 1923 } 1924 1925 /* 1926 * Generating an inode and adding it into @pid->inodes, so that task will 1927 * invalidate inode's dentry before being released. 1928 * 1929 * This helper is used for creating dir-type entries under '/proc' and 1930 * '/proc/<tgid>/task'. Other entries(eg. fd, stat) under '/proc/<tgid>' 1931 * can be released by invalidating '/proc/<tgid>' dentry. 1932 * In theory, dentries under '/proc/<tgid>/task' can also be released by 1933 * invalidating '/proc/<tgid>' dentry, we reserve it to handle single 1934 * thread exiting situation: Any one of threads should invalidate its 1935 * '/proc/<tgid>/task/<pid>' dentry before released. 1936 */ 1937 static struct inode *proc_pid_make_base_inode(struct super_block *sb, 1938 struct task_struct *task, umode_t mode) 1939 { 1940 struct inode *inode; 1941 struct proc_inode *ei; 1942 struct pid *pid; 1943 1944 inode = proc_pid_make_inode(sb, task, mode); 1945 if (!inode) 1946 return NULL; 1947 1948 /* Let proc_flush_pid find this directory inode */ 1949 ei = PROC_I(inode); 1950 pid = ei->pid; 1951 spin_lock(&pid->lock); 1952 hlist_add_head_rcu(&ei->sibling_inodes, &pid->inodes); 1953 spin_unlock(&pid->lock); 1954 1955 return inode; 1956 } 1957 1958 int pid_getattr(struct mnt_idmap *idmap, const struct path *path, 1959 struct kstat *stat, u32 request_mask, unsigned int query_flags) 1960 { 1961 struct inode *inode = d_inode(path->dentry); 1962 struct proc_fs_info *fs_info = proc_sb_info(inode->i_sb); 1963 struct task_struct *task; 1964 1965 generic_fillattr(&nop_mnt_idmap, request_mask, inode, stat); 1966 1967 stat->uid = GLOBAL_ROOT_UID; 1968 stat->gid = GLOBAL_ROOT_GID; 1969 rcu_read_lock(); 1970 task = pid_task(proc_pid(inode), PIDTYPE_PID); 1971 if (task) { 1972 if (!has_pid_permissions(fs_info, task, HIDEPID_INVISIBLE)) { 1973 rcu_read_unlock(); 1974 /* 1975 * This doesn't prevent learning whether PID exists, 1976 * it only makes getattr() consistent with readdir(). 1977 */ 1978 return -ENOENT; 1979 } 1980 task_dump_owner(task, inode->i_mode, &stat->uid, &stat->gid); 1981 } 1982 rcu_read_unlock(); 1983 return 0; 1984 } 1985 1986 /* dentry stuff */ 1987 1988 /* 1989 * Set <pid>/... inode ownership (can change due to setuid(), etc.) 1990 */ 1991 void pid_update_inode(struct task_struct *task, struct inode *inode) 1992 { 1993 task_dump_owner(task, inode->i_mode, &inode->i_uid, &inode->i_gid); 1994 1995 inode->i_mode &= ~(S_ISUID | S_ISGID); 1996 security_task_to_inode(task, inode); 1997 } 1998 1999 /* 2000 * Rewrite the inode's ownerships here because the owning task may have 2001 * performed a setuid(), etc. 2002 * 2003 */ 2004 static int pid_revalidate(struct dentry *dentry, unsigned int flags) 2005 { 2006 struct inode *inode; 2007 struct task_struct *task; 2008 int ret = 0; 2009 2010 rcu_read_lock(); 2011 inode = d_inode_rcu(dentry); 2012 if (!inode) 2013 goto out; 2014 task = pid_task(proc_pid(inode), PIDTYPE_PID); 2015 2016 if (task) { 2017 pid_update_inode(task, inode); 2018 ret = 1; 2019 } 2020 out: 2021 rcu_read_unlock(); 2022 return ret; 2023 } 2024 2025 static inline bool proc_inode_is_dead(struct inode *inode) 2026 { 2027 return !proc_pid(inode)->tasks[PIDTYPE_PID].first; 2028 } 2029 2030 int pid_delete_dentry(const struct dentry *dentry) 2031 { 2032 /* Is the task we represent dead? 2033 * If so, then don't put the dentry on the lru list, 2034 * kill it immediately. 2035 */ 2036 return proc_inode_is_dead(d_inode(dentry)); 2037 } 2038 2039 const struct dentry_operations pid_dentry_operations = 2040 { 2041 .d_revalidate = pid_revalidate, 2042 .d_delete = pid_delete_dentry, 2043 }; 2044 2045 /* Lookups */ 2046 2047 /* 2048 * Fill a directory entry. 2049 * 2050 * If possible create the dcache entry and derive our inode number and 2051 * file type from dcache entry. 2052 * 2053 * Since all of the proc inode numbers are dynamically generated, the inode 2054 * numbers do not exist until the inode is cache. This means creating 2055 * the dcache entry in readdir is necessary to keep the inode numbers 2056 * reported by readdir in sync with the inode numbers reported 2057 * by stat. 2058 */ 2059 bool proc_fill_cache(struct file *file, struct dir_context *ctx, 2060 const char *name, unsigned int len, 2061 instantiate_t instantiate, struct task_struct *task, const void *ptr) 2062 { 2063 struct dentry *child, *dir = file->f_path.dentry; 2064 struct qstr qname = QSTR_INIT(name, len); 2065 struct inode *inode; 2066 unsigned type = DT_UNKNOWN; 2067 ino_t ino = 1; 2068 2069 child = d_hash_and_lookup(dir, &qname); 2070 if (!child) { 2071 DECLARE_WAIT_QUEUE_HEAD_ONSTACK(wq); 2072 child = d_alloc_parallel(dir, &qname, &wq); 2073 if (IS_ERR(child)) 2074 goto end_instantiate; 2075 if (d_in_lookup(child)) { 2076 struct dentry *res; 2077 res = instantiate(child, task, ptr); 2078 d_lookup_done(child); 2079 if (unlikely(res)) { 2080 dput(child); 2081 child = res; 2082 if (IS_ERR(child)) 2083 goto end_instantiate; 2084 } 2085 } 2086 } 2087 inode = d_inode(child); 2088 ino = inode->i_ino; 2089 type = inode->i_mode >> 12; 2090 dput(child); 2091 end_instantiate: 2092 return dir_emit(ctx, name, len, ino, type); 2093 } 2094 2095 /* 2096 * dname_to_vma_addr - maps a dentry name into two unsigned longs 2097 * which represent vma start and end addresses. 2098 */ 2099 static int dname_to_vma_addr(struct dentry *dentry, 2100 unsigned long *start, unsigned long *end) 2101 { 2102 const char *str = dentry->d_name.name; 2103 unsigned long long sval, eval; 2104 unsigned int len; 2105 2106 if (str[0] == '0' && str[1] != '-') 2107 return -EINVAL; 2108 len = _parse_integer(str, 16, &sval); 2109 if (len & KSTRTOX_OVERFLOW) 2110 return -EINVAL; 2111 if (sval != (unsigned long)sval) 2112 return -EINVAL; 2113 str += len; 2114 2115 if (*str != '-') 2116 return -EINVAL; 2117 str++; 2118 2119 if (str[0] == '0' && str[1]) 2120 return -EINVAL; 2121 len = _parse_integer(str, 16, &eval); 2122 if (len & KSTRTOX_OVERFLOW) 2123 return -EINVAL; 2124 if (eval != (unsigned long)eval) 2125 return -EINVAL; 2126 str += len; 2127 2128 if (*str != '\0') 2129 return -EINVAL; 2130 2131 *start = sval; 2132 *end = eval; 2133 2134 return 0; 2135 } 2136 2137 static int map_files_d_revalidate(struct dentry *dentry, unsigned int flags) 2138 { 2139 unsigned long vm_start, vm_end; 2140 bool exact_vma_exists = false; 2141 struct mm_struct *mm = NULL; 2142 struct task_struct *task; 2143 struct inode *inode; 2144 int status = 0; 2145 2146 if (flags & LOOKUP_RCU) 2147 return -ECHILD; 2148 2149 inode = d_inode(dentry); 2150 task = get_proc_task(inode); 2151 if (!task) 2152 goto out_notask; 2153 2154 mm = mm_access(task, PTRACE_MODE_READ_FSCREDS); 2155 if (IS_ERR_OR_NULL(mm)) 2156 goto out; 2157 2158 if (!dname_to_vma_addr(dentry, &vm_start, &vm_end)) { 2159 status = mmap_read_lock_killable(mm); 2160 if (!status) { 2161 exact_vma_exists = !!find_exact_vma(mm, vm_start, 2162 vm_end); 2163 mmap_read_unlock(mm); 2164 } 2165 } 2166 2167 mmput(mm); 2168 2169 if (exact_vma_exists) { 2170 task_dump_owner(task, 0, &inode->i_uid, &inode->i_gid); 2171 2172 security_task_to_inode(task, inode); 2173 status = 1; 2174 } 2175 2176 out: 2177 put_task_struct(task); 2178 2179 out_notask: 2180 return status; 2181 } 2182 2183 static const struct dentry_operations tid_map_files_dentry_operations = { 2184 .d_revalidate = map_files_d_revalidate, 2185 .d_delete = pid_delete_dentry, 2186 }; 2187 2188 static int map_files_get_link(struct dentry *dentry, struct path *path) 2189 { 2190 unsigned long vm_start, vm_end; 2191 struct vm_area_struct *vma; 2192 struct task_struct *task; 2193 struct mm_struct *mm; 2194 int rc; 2195 2196 rc = -ENOENT; 2197 task = get_proc_task(d_inode(dentry)); 2198 if (!task) 2199 goto out; 2200 2201 mm = get_task_mm(task); 2202 put_task_struct(task); 2203 if (!mm) 2204 goto out; 2205 2206 rc = dname_to_vma_addr(dentry, &vm_start, &vm_end); 2207 if (rc) 2208 goto out_mmput; 2209 2210 rc = mmap_read_lock_killable(mm); 2211 if (rc) 2212 goto out_mmput; 2213 2214 rc = -ENOENT; 2215 vma = find_exact_vma(mm, vm_start, vm_end); 2216 if (vma && vma->vm_file) { 2217 *path = *file_user_path(vma->vm_file); 2218 path_get(path); 2219 rc = 0; 2220 } 2221 mmap_read_unlock(mm); 2222 2223 out_mmput: 2224 mmput(mm); 2225 out: 2226 return rc; 2227 } 2228 2229 struct map_files_info { 2230 unsigned long start; 2231 unsigned long end; 2232 fmode_t mode; 2233 }; 2234 2235 /* 2236 * Only allow CAP_SYS_ADMIN and CAP_CHECKPOINT_RESTORE to follow the links, due 2237 * to concerns about how the symlinks may be used to bypass permissions on 2238 * ancestor directories in the path to the file in question. 2239 */ 2240 static const char * 2241 proc_map_files_get_link(struct dentry *dentry, 2242 struct inode *inode, 2243 struct delayed_call *done) 2244 { 2245 if (!checkpoint_restore_ns_capable(&init_user_ns)) 2246 return ERR_PTR(-EPERM); 2247 2248 return proc_pid_get_link(dentry, inode, done); 2249 } 2250 2251 /* 2252 * Identical to proc_pid_link_inode_operations except for get_link() 2253 */ 2254 static const struct inode_operations proc_map_files_link_inode_operations = { 2255 .readlink = proc_pid_readlink, 2256 .get_link = proc_map_files_get_link, 2257 .setattr = proc_setattr, 2258 }; 2259 2260 static struct dentry * 2261 proc_map_files_instantiate(struct dentry *dentry, 2262 struct task_struct *task, const void *ptr) 2263 { 2264 fmode_t mode = (fmode_t)(unsigned long)ptr; 2265 struct proc_inode *ei; 2266 struct inode *inode; 2267 2268 inode = proc_pid_make_inode(dentry->d_sb, task, S_IFLNK | 2269 ((mode & FMODE_READ ) ? S_IRUSR : 0) | 2270 ((mode & FMODE_WRITE) ? S_IWUSR : 0)); 2271 if (!inode) 2272 return ERR_PTR(-ENOENT); 2273 2274 ei = PROC_I(inode); 2275 ei->op.proc_get_link = map_files_get_link; 2276 2277 inode->i_op = &proc_map_files_link_inode_operations; 2278 inode->i_size = 64; 2279 2280 d_set_d_op(dentry, &tid_map_files_dentry_operations); 2281 return d_splice_alias(inode, dentry); 2282 } 2283 2284 static struct dentry *proc_map_files_lookup(struct inode *dir, 2285 struct dentry *dentry, unsigned int flags) 2286 { 2287 unsigned long vm_start, vm_end; 2288 struct vm_area_struct *vma; 2289 struct task_struct *task; 2290 struct dentry *result; 2291 struct mm_struct *mm; 2292 2293 result = ERR_PTR(-ENOENT); 2294 task = get_proc_task(dir); 2295 if (!task) 2296 goto out; 2297 2298 result = ERR_PTR(-EACCES); 2299 if (!ptrace_may_access(task, PTRACE_MODE_READ_FSCREDS)) 2300 goto out_put_task; 2301 2302 result = ERR_PTR(-ENOENT); 2303 if (dname_to_vma_addr(dentry, &vm_start, &vm_end)) 2304 goto out_put_task; 2305 2306 mm = get_task_mm(task); 2307 if (!mm) 2308 goto out_put_task; 2309 2310 result = ERR_PTR(-EINTR); 2311 if (mmap_read_lock_killable(mm)) 2312 goto out_put_mm; 2313 2314 result = ERR_PTR(-ENOENT); 2315 vma = find_exact_vma(mm, vm_start, vm_end); 2316 if (!vma) 2317 goto out_no_vma; 2318 2319 if (vma->vm_file) 2320 result = proc_map_files_instantiate(dentry, task, 2321 (void *)(unsigned long)vma->vm_file->f_mode); 2322 2323 out_no_vma: 2324 mmap_read_unlock(mm); 2325 out_put_mm: 2326 mmput(mm); 2327 out_put_task: 2328 put_task_struct(task); 2329 out: 2330 return result; 2331 } 2332 2333 static const struct inode_operations proc_map_files_inode_operations = { 2334 .lookup = proc_map_files_lookup, 2335 .permission = proc_fd_permission, 2336 .setattr = proc_setattr, 2337 }; 2338 2339 static int 2340 proc_map_files_readdir(struct file *file, struct dir_context *ctx) 2341 { 2342 struct vm_area_struct *vma; 2343 struct task_struct *task; 2344 struct mm_struct *mm; 2345 unsigned long nr_files, pos, i; 2346 GENRADIX(struct map_files_info) fa; 2347 struct map_files_info *p; 2348 int ret; 2349 struct vma_iterator vmi; 2350 2351 genradix_init(&fa); 2352 2353 ret = -ENOENT; 2354 task = get_proc_task(file_inode(file)); 2355 if (!task) 2356 goto out; 2357 2358 ret = -EACCES; 2359 if (!ptrace_may_access(task, PTRACE_MODE_READ_FSCREDS)) 2360 goto out_put_task; 2361 2362 ret = 0; 2363 if (!dir_emit_dots(file, ctx)) 2364 goto out_put_task; 2365 2366 mm = get_task_mm(task); 2367 if (!mm) 2368 goto out_put_task; 2369 2370 ret = mmap_read_lock_killable(mm); 2371 if (ret) { 2372 mmput(mm); 2373 goto out_put_task; 2374 } 2375 2376 nr_files = 0; 2377 2378 /* 2379 * We need two passes here: 2380 * 2381 * 1) Collect vmas of mapped files with mmap_lock taken 2382 * 2) Release mmap_lock and instantiate entries 2383 * 2384 * otherwise we get lockdep complained, since filldir() 2385 * routine might require mmap_lock taken in might_fault(). 2386 */ 2387 2388 pos = 2; 2389 vma_iter_init(&vmi, mm, 0); 2390 for_each_vma(vmi, vma) { 2391 if (!vma->vm_file) 2392 continue; 2393 if (++pos <= ctx->pos) 2394 continue; 2395 2396 p = genradix_ptr_alloc(&fa, nr_files++, GFP_KERNEL); 2397 if (!p) { 2398 ret = -ENOMEM; 2399 mmap_read_unlock(mm); 2400 mmput(mm); 2401 goto out_put_task; 2402 } 2403 2404 p->start = vma->vm_start; 2405 p->end = vma->vm_end; 2406 p->mode = vma->vm_file->f_mode; 2407 } 2408 mmap_read_unlock(mm); 2409 mmput(mm); 2410 2411 for (i = 0; i < nr_files; i++) { 2412 char buf[4 * sizeof(long) + 2]; /* max: %lx-%lx\0 */ 2413 unsigned int len; 2414 2415 p = genradix_ptr(&fa, i); 2416 len = snprintf(buf, sizeof(buf), "%lx-%lx", p->start, p->end); 2417 if (!proc_fill_cache(file, ctx, 2418 buf, len, 2419 proc_map_files_instantiate, 2420 task, 2421 (void *)(unsigned long)p->mode)) 2422 break; 2423 ctx->pos++; 2424 } 2425 2426 out_put_task: 2427 put_task_struct(task); 2428 out: 2429 genradix_free(&fa); 2430 return ret; 2431 } 2432 2433 static const struct file_operations proc_map_files_operations = { 2434 .read = generic_read_dir, 2435 .iterate_shared = proc_map_files_readdir, 2436 .llseek = generic_file_llseek, 2437 }; 2438 2439 #if defined(CONFIG_CHECKPOINT_RESTORE) && defined(CONFIG_POSIX_TIMERS) 2440 struct timers_private { 2441 struct pid *pid; 2442 struct task_struct *task; 2443 struct sighand_struct *sighand; 2444 struct pid_namespace *ns; 2445 unsigned long flags; 2446 }; 2447 2448 static void *timers_start(struct seq_file *m, loff_t *pos) 2449 { 2450 struct timers_private *tp = m->private; 2451 2452 tp->task = get_pid_task(tp->pid, PIDTYPE_PID); 2453 if (!tp->task) 2454 return ERR_PTR(-ESRCH); 2455 2456 tp->sighand = lock_task_sighand(tp->task, &tp->flags); 2457 if (!tp->sighand) 2458 return ERR_PTR(-ESRCH); 2459 2460 return seq_list_start(&tp->task->signal->posix_timers, *pos); 2461 } 2462 2463 static void *timers_next(struct seq_file *m, void *v, loff_t *pos) 2464 { 2465 struct timers_private *tp = m->private; 2466 return seq_list_next(v, &tp->task->signal->posix_timers, pos); 2467 } 2468 2469 static void timers_stop(struct seq_file *m, void *v) 2470 { 2471 struct timers_private *tp = m->private; 2472 2473 if (tp->sighand) { 2474 unlock_task_sighand(tp->task, &tp->flags); 2475 tp->sighand = NULL; 2476 } 2477 2478 if (tp->task) { 2479 put_task_struct(tp->task); 2480 tp->task = NULL; 2481 } 2482 } 2483 2484 static int show_timer(struct seq_file *m, void *v) 2485 { 2486 struct k_itimer *timer; 2487 struct timers_private *tp = m->private; 2488 int notify; 2489 static const char * const nstr[] = { 2490 [SIGEV_SIGNAL] = "signal", 2491 [SIGEV_NONE] = "none", 2492 [SIGEV_THREAD] = "thread", 2493 }; 2494 2495 timer = list_entry((struct list_head *)v, struct k_itimer, list); 2496 notify = timer->it_sigev_notify; 2497 2498 seq_printf(m, "ID: %d\n", timer->it_id); 2499 seq_printf(m, "signal: %d/%px\n", 2500 timer->sigq->info.si_signo, 2501 timer->sigq->info.si_value.sival_ptr); 2502 seq_printf(m, "notify: %s/%s.%d\n", 2503 nstr[notify & ~SIGEV_THREAD_ID], 2504 (notify & SIGEV_THREAD_ID) ? "tid" : "pid", 2505 pid_nr_ns(timer->it_pid, tp->ns)); 2506 seq_printf(m, "ClockID: %d\n", timer->it_clock); 2507 2508 return 0; 2509 } 2510 2511 static const struct seq_operations proc_timers_seq_ops = { 2512 .start = timers_start, 2513 .next = timers_next, 2514 .stop = timers_stop, 2515 .show = show_timer, 2516 }; 2517 2518 static int proc_timers_open(struct inode *inode, struct file *file) 2519 { 2520 struct timers_private *tp; 2521 2522 tp = __seq_open_private(file, &proc_timers_seq_ops, 2523 sizeof(struct timers_private)); 2524 if (!tp) 2525 return -ENOMEM; 2526 2527 tp->pid = proc_pid(inode); 2528 tp->ns = proc_pid_ns(inode->i_sb); 2529 return 0; 2530 } 2531 2532 static const struct file_operations proc_timers_operations = { 2533 .open = proc_timers_open, 2534 .read = seq_read, 2535 .llseek = seq_lseek, 2536 .release = seq_release_private, 2537 }; 2538 #endif 2539 2540 static ssize_t timerslack_ns_write(struct file *file, const char __user *buf, 2541 size_t count, loff_t *offset) 2542 { 2543 struct inode *inode = file_inode(file); 2544 struct task_struct *p; 2545 u64 slack_ns; 2546 int err; 2547 2548 err = kstrtoull_from_user(buf, count, 10, &slack_ns); 2549 if (err < 0) 2550 return err; 2551 2552 p = get_proc_task(inode); 2553 if (!p) 2554 return -ESRCH; 2555 2556 if (p != current) { 2557 rcu_read_lock(); 2558 if (!ns_capable(__task_cred(p)->user_ns, CAP_SYS_NICE)) { 2559 rcu_read_unlock(); 2560 count = -EPERM; 2561 goto out; 2562 } 2563 rcu_read_unlock(); 2564 2565 err = security_task_setscheduler(p); 2566 if (err) { 2567 count = err; 2568 goto out; 2569 } 2570 } 2571 2572 task_lock(p); 2573 if (slack_ns == 0) 2574 p->timer_slack_ns = p->default_timer_slack_ns; 2575 else 2576 p->timer_slack_ns = slack_ns; 2577 task_unlock(p); 2578 2579 out: 2580 put_task_struct(p); 2581 2582 return count; 2583 } 2584 2585 static int timerslack_ns_show(struct seq_file *m, void *v) 2586 { 2587 struct inode *inode = m->private; 2588 struct task_struct *p; 2589 int err = 0; 2590 2591 p = get_proc_task(inode); 2592 if (!p) 2593 return -ESRCH; 2594 2595 if (p != current) { 2596 rcu_read_lock(); 2597 if (!ns_capable(__task_cred(p)->user_ns, CAP_SYS_NICE)) { 2598 rcu_read_unlock(); 2599 err = -EPERM; 2600 goto out; 2601 } 2602 rcu_read_unlock(); 2603 2604 err = security_task_getscheduler(p); 2605 if (err) 2606 goto out; 2607 } 2608 2609 task_lock(p); 2610 seq_printf(m, "%llu\n", p->timer_slack_ns); 2611 task_unlock(p); 2612 2613 out: 2614 put_task_struct(p); 2615 2616 return err; 2617 } 2618 2619 static int timerslack_ns_open(struct inode *inode, struct file *filp) 2620 { 2621 return single_open(filp, timerslack_ns_show, inode); 2622 } 2623 2624 static const struct file_operations proc_pid_set_timerslack_ns_operations = { 2625 .open = timerslack_ns_open, 2626 .read = seq_read, 2627 .write = timerslack_ns_write, 2628 .llseek = seq_lseek, 2629 .release = single_release, 2630 }; 2631 2632 static struct dentry *proc_pident_instantiate(struct dentry *dentry, 2633 struct task_struct *task, const void *ptr) 2634 { 2635 const struct pid_entry *p = ptr; 2636 struct inode *inode; 2637 struct proc_inode *ei; 2638 2639 inode = proc_pid_make_inode(dentry->d_sb, task, p->mode); 2640 if (!inode) 2641 return ERR_PTR(-ENOENT); 2642 2643 ei = PROC_I(inode); 2644 if (S_ISDIR(inode->i_mode)) 2645 set_nlink(inode, 2); /* Use getattr to fix if necessary */ 2646 if (p->iop) 2647 inode->i_op = p->iop; 2648 if (p->fop) 2649 inode->i_fop = p->fop; 2650 ei->op = p->op; 2651 pid_update_inode(task, inode); 2652 d_set_d_op(dentry, &pid_dentry_operations); 2653 return d_splice_alias(inode, dentry); 2654 } 2655 2656 static struct dentry *proc_pident_lookup(struct inode *dir, 2657 struct dentry *dentry, 2658 const struct pid_entry *p, 2659 const struct pid_entry *end) 2660 { 2661 struct task_struct *task = get_proc_task(dir); 2662 struct dentry *res = ERR_PTR(-ENOENT); 2663 2664 if (!task) 2665 goto out_no_task; 2666 2667 /* 2668 * Yes, it does not scale. And it should not. Don't add 2669 * new entries into /proc/<tgid>/ without very good reasons. 2670 */ 2671 for (; p < end; p++) { 2672 if (p->len != dentry->d_name.len) 2673 continue; 2674 if (!memcmp(dentry->d_name.name, p->name, p->len)) { 2675 res = proc_pident_instantiate(dentry, task, p); 2676 break; 2677 } 2678 } 2679 put_task_struct(task); 2680 out_no_task: 2681 return res; 2682 } 2683 2684 static int proc_pident_readdir(struct file *file, struct dir_context *ctx, 2685 const struct pid_entry *ents, unsigned int nents) 2686 { 2687 struct task_struct *task = get_proc_task(file_inode(file)); 2688 const struct pid_entry *p; 2689 2690 if (!task) 2691 return -ENOENT; 2692 2693 if (!dir_emit_dots(file, ctx)) 2694 goto out; 2695 2696 if (ctx->pos >= nents + 2) 2697 goto out; 2698 2699 for (p = ents + (ctx->pos - 2); p < ents + nents; p++) { 2700 if (!proc_fill_cache(file, ctx, p->name, p->len, 2701 proc_pident_instantiate, task, p)) 2702 break; 2703 ctx->pos++; 2704 } 2705 out: 2706 put_task_struct(task); 2707 return 0; 2708 } 2709 2710 #ifdef CONFIG_SECURITY 2711 static int proc_pid_attr_open(struct inode *inode, struct file *file) 2712 { 2713 file->private_data = NULL; 2714 __mem_open(inode, file, PTRACE_MODE_READ_FSCREDS); 2715 return 0; 2716 } 2717 2718 static ssize_t proc_pid_attr_read(struct file * file, char __user * buf, 2719 size_t count, loff_t *ppos) 2720 { 2721 struct inode * inode = file_inode(file); 2722 char *p = NULL; 2723 ssize_t length; 2724 struct task_struct *task = get_proc_task(inode); 2725 2726 if (!task) 2727 return -ESRCH; 2728 2729 length = security_getprocattr(task, PROC_I(inode)->op.lsm, 2730 file->f_path.dentry->d_name.name, 2731 &p); 2732 put_task_struct(task); 2733 if (length > 0) 2734 length = simple_read_from_buffer(buf, count, ppos, p, length); 2735 kfree(p); 2736 return length; 2737 } 2738 2739 static ssize_t proc_pid_attr_write(struct file * file, const char __user * buf, 2740 size_t count, loff_t *ppos) 2741 { 2742 struct inode * inode = file_inode(file); 2743 struct task_struct *task; 2744 void *page; 2745 int rv; 2746 2747 /* A task may only write when it was the opener. */ 2748 if (file->private_data != current->mm) 2749 return -EPERM; 2750 2751 rcu_read_lock(); 2752 task = pid_task(proc_pid(inode), PIDTYPE_PID); 2753 if (!task) { 2754 rcu_read_unlock(); 2755 return -ESRCH; 2756 } 2757 /* A task may only write its own attributes. */ 2758 if (current != task) { 2759 rcu_read_unlock(); 2760 return -EACCES; 2761 } 2762 /* Prevent changes to overridden credentials. */ 2763 if (current_cred() != current_real_cred()) { 2764 rcu_read_unlock(); 2765 return -EBUSY; 2766 } 2767 rcu_read_unlock(); 2768 2769 if (count > PAGE_SIZE) 2770 count = PAGE_SIZE; 2771 2772 /* No partial writes. */ 2773 if (*ppos != 0) 2774 return -EINVAL; 2775 2776 page = memdup_user(buf, count); 2777 if (IS_ERR(page)) { 2778 rv = PTR_ERR(page); 2779 goto out; 2780 } 2781 2782 /* Guard against adverse ptrace interaction */ 2783 rv = mutex_lock_interruptible(¤t->signal->cred_guard_mutex); 2784 if (rv < 0) 2785 goto out_free; 2786 2787 rv = security_setprocattr(PROC_I(inode)->op.lsm, 2788 file->f_path.dentry->d_name.name, page, 2789 count); 2790 mutex_unlock(¤t->signal->cred_guard_mutex); 2791 out_free: 2792 kfree(page); 2793 out: 2794 return rv; 2795 } 2796 2797 static const struct file_operations proc_pid_attr_operations = { 2798 .open = proc_pid_attr_open, 2799 .read = proc_pid_attr_read, 2800 .write = proc_pid_attr_write, 2801 .llseek = generic_file_llseek, 2802 .release = mem_release, 2803 }; 2804 2805 #define LSM_DIR_OPS(LSM) \ 2806 static int proc_##LSM##_attr_dir_iterate(struct file *filp, \ 2807 struct dir_context *ctx) \ 2808 { \ 2809 return proc_pident_readdir(filp, ctx, \ 2810 LSM##_attr_dir_stuff, \ 2811 ARRAY_SIZE(LSM##_attr_dir_stuff)); \ 2812 } \ 2813 \ 2814 static const struct file_operations proc_##LSM##_attr_dir_ops = { \ 2815 .read = generic_read_dir, \ 2816 .iterate_shared = proc_##LSM##_attr_dir_iterate, \ 2817 .llseek = default_llseek, \ 2818 }; \ 2819 \ 2820 static struct dentry *proc_##LSM##_attr_dir_lookup(struct inode *dir, \ 2821 struct dentry *dentry, unsigned int flags) \ 2822 { \ 2823 return proc_pident_lookup(dir, dentry, \ 2824 LSM##_attr_dir_stuff, \ 2825 LSM##_attr_dir_stuff + ARRAY_SIZE(LSM##_attr_dir_stuff)); \ 2826 } \ 2827 \ 2828 static const struct inode_operations proc_##LSM##_attr_dir_inode_ops = { \ 2829 .lookup = proc_##LSM##_attr_dir_lookup, \ 2830 .getattr = pid_getattr, \ 2831 .setattr = proc_setattr, \ 2832 } 2833 2834 #ifdef CONFIG_SECURITY_SMACK 2835 static const struct pid_entry smack_attr_dir_stuff[] = { 2836 ATTR("smack", "current", 0666), 2837 }; 2838 LSM_DIR_OPS(smack); 2839 #endif 2840 2841 #ifdef CONFIG_SECURITY_APPARMOR 2842 static const struct pid_entry apparmor_attr_dir_stuff[] = { 2843 ATTR("apparmor", "current", 0666), 2844 ATTR("apparmor", "prev", 0444), 2845 ATTR("apparmor", "exec", 0666), 2846 }; 2847 LSM_DIR_OPS(apparmor); 2848 #endif 2849 2850 static const struct pid_entry attr_dir_stuff[] = { 2851 ATTR(NULL, "current", 0666), 2852 ATTR(NULL, "prev", 0444), 2853 ATTR(NULL, "exec", 0666), 2854 ATTR(NULL, "fscreate", 0666), 2855 ATTR(NULL, "keycreate", 0666), 2856 ATTR(NULL, "sockcreate", 0666), 2857 #ifdef CONFIG_SECURITY_SMACK 2858 DIR("smack", 0555, 2859 proc_smack_attr_dir_inode_ops, proc_smack_attr_dir_ops), 2860 #endif 2861 #ifdef CONFIG_SECURITY_APPARMOR 2862 DIR("apparmor", 0555, 2863 proc_apparmor_attr_dir_inode_ops, proc_apparmor_attr_dir_ops), 2864 #endif 2865 }; 2866 2867 static int proc_attr_dir_readdir(struct file *file, struct dir_context *ctx) 2868 { 2869 return proc_pident_readdir(file, ctx, 2870 attr_dir_stuff, ARRAY_SIZE(attr_dir_stuff)); 2871 } 2872 2873 static const struct file_operations proc_attr_dir_operations = { 2874 .read = generic_read_dir, 2875 .iterate_shared = proc_attr_dir_readdir, 2876 .llseek = generic_file_llseek, 2877 }; 2878 2879 static struct dentry *proc_attr_dir_lookup(struct inode *dir, 2880 struct dentry *dentry, unsigned int flags) 2881 { 2882 return proc_pident_lookup(dir, dentry, 2883 attr_dir_stuff, 2884 attr_dir_stuff + ARRAY_SIZE(attr_dir_stuff)); 2885 } 2886 2887 static const struct inode_operations proc_attr_dir_inode_operations = { 2888 .lookup = proc_attr_dir_lookup, 2889 .getattr = pid_getattr, 2890 .setattr = proc_setattr, 2891 }; 2892 2893 #endif 2894 2895 #ifdef CONFIG_ELF_CORE 2896 static ssize_t proc_coredump_filter_read(struct file *file, char __user *buf, 2897 size_t count, loff_t *ppos) 2898 { 2899 struct task_struct *task = get_proc_task(file_inode(file)); 2900 struct mm_struct *mm; 2901 char buffer[PROC_NUMBUF]; 2902 size_t len; 2903 int ret; 2904 2905 if (!task) 2906 return -ESRCH; 2907 2908 ret = 0; 2909 mm = get_task_mm(task); 2910 if (mm) { 2911 len = snprintf(buffer, sizeof(buffer), "%08lx\n", 2912 ((mm->flags & MMF_DUMP_FILTER_MASK) >> 2913 MMF_DUMP_FILTER_SHIFT)); 2914 mmput(mm); 2915 ret = simple_read_from_buffer(buf, count, ppos, buffer, len); 2916 } 2917 2918 put_task_struct(task); 2919 2920 return ret; 2921 } 2922 2923 static ssize_t proc_coredump_filter_write(struct file *file, 2924 const char __user *buf, 2925 size_t count, 2926 loff_t *ppos) 2927 { 2928 struct task_struct *task; 2929 struct mm_struct *mm; 2930 unsigned int val; 2931 int ret; 2932 int i; 2933 unsigned long mask; 2934 2935 ret = kstrtouint_from_user(buf, count, 0, &val); 2936 if (ret < 0) 2937 return ret; 2938 2939 ret = -ESRCH; 2940 task = get_proc_task(file_inode(file)); 2941 if (!task) 2942 goto out_no_task; 2943 2944 mm = get_task_mm(task); 2945 if (!mm) 2946 goto out_no_mm; 2947 ret = 0; 2948 2949 for (i = 0, mask = 1; i < MMF_DUMP_FILTER_BITS; i++, mask <<= 1) { 2950 if (val & mask) 2951 set_bit(i + MMF_DUMP_FILTER_SHIFT, &mm->flags); 2952 else 2953 clear_bit(i + MMF_DUMP_FILTER_SHIFT, &mm->flags); 2954 } 2955 2956 mmput(mm); 2957 out_no_mm: 2958 put_task_struct(task); 2959 out_no_task: 2960 if (ret < 0) 2961 return ret; 2962 return count; 2963 } 2964 2965 static const struct file_operations proc_coredump_filter_operations = { 2966 .read = proc_coredump_filter_read, 2967 .write = proc_coredump_filter_write, 2968 .llseek = generic_file_llseek, 2969 }; 2970 #endif 2971 2972 #ifdef CONFIG_TASK_IO_ACCOUNTING 2973 static int do_io_accounting(struct task_struct *task, struct seq_file *m, int whole) 2974 { 2975 struct task_io_accounting acct; 2976 int result; 2977 2978 result = down_read_killable(&task->signal->exec_update_lock); 2979 if (result) 2980 return result; 2981 2982 if (!ptrace_may_access(task, PTRACE_MODE_READ_FSCREDS)) { 2983 result = -EACCES; 2984 goto out_unlock; 2985 } 2986 2987 if (whole) { 2988 struct signal_struct *sig = task->signal; 2989 struct task_struct *t; 2990 unsigned int seq = 1; 2991 unsigned long flags; 2992 2993 rcu_read_lock(); 2994 do { 2995 seq++; /* 2 on the 1st/lockless path, otherwise odd */ 2996 flags = read_seqbegin_or_lock_irqsave(&sig->stats_lock, &seq); 2997 2998 acct = sig->ioac; 2999 __for_each_thread(sig, t) 3000 task_io_accounting_add(&acct, &t->ioac); 3001 3002 } while (need_seqretry(&sig->stats_lock, seq)); 3003 done_seqretry_irqrestore(&sig->stats_lock, seq, flags); 3004 rcu_read_unlock(); 3005 } else { 3006 acct = task->ioac; 3007 } 3008 3009 seq_printf(m, 3010 "rchar: %llu\n" 3011 "wchar: %llu\n" 3012 "syscr: %llu\n" 3013 "syscw: %llu\n" 3014 "read_bytes: %llu\n" 3015 "write_bytes: %llu\n" 3016 "cancelled_write_bytes: %llu\n", 3017 (unsigned long long)acct.rchar, 3018 (unsigned long long)acct.wchar, 3019 (unsigned long long)acct.syscr, 3020 (unsigned long long)acct.syscw, 3021 (unsigned long long)acct.read_bytes, 3022 (unsigned long long)acct.write_bytes, 3023 (unsigned long long)acct.cancelled_write_bytes); 3024 result = 0; 3025 3026 out_unlock: 3027 up_read(&task->signal->exec_update_lock); 3028 return result; 3029 } 3030 3031 static int proc_tid_io_accounting(struct seq_file *m, struct pid_namespace *ns, 3032 struct pid *pid, struct task_struct *task) 3033 { 3034 return do_io_accounting(task, m, 0); 3035 } 3036 3037 static int proc_tgid_io_accounting(struct seq_file *m, struct pid_namespace *ns, 3038 struct pid *pid, struct task_struct *task) 3039 { 3040 return do_io_accounting(task, m, 1); 3041 } 3042 #endif /* CONFIG_TASK_IO_ACCOUNTING */ 3043 3044 #ifdef CONFIG_USER_NS 3045 static int proc_id_map_open(struct inode *inode, struct file *file, 3046 const struct seq_operations *seq_ops) 3047 { 3048 struct user_namespace *ns = NULL; 3049 struct task_struct *task; 3050 struct seq_file *seq; 3051 int ret = -EINVAL; 3052 3053 task = get_proc_task(inode); 3054 if (task) { 3055 rcu_read_lock(); 3056 ns = get_user_ns(task_cred_xxx(task, user_ns)); 3057 rcu_read_unlock(); 3058 put_task_struct(task); 3059 } 3060 if (!ns) 3061 goto err; 3062 3063 ret = seq_open(file, seq_ops); 3064 if (ret) 3065 goto err_put_ns; 3066 3067 seq = file->private_data; 3068 seq->private = ns; 3069 3070 return 0; 3071 err_put_ns: 3072 put_user_ns(ns); 3073 err: 3074 return ret; 3075 } 3076 3077 static int proc_id_map_release(struct inode *inode, struct file *file) 3078 { 3079 struct seq_file *seq = file->private_data; 3080 struct user_namespace *ns = seq->private; 3081 put_user_ns(ns); 3082 return seq_release(inode, file); 3083 } 3084 3085 static int proc_uid_map_open(struct inode *inode, struct file *file) 3086 { 3087 return proc_id_map_open(inode, file, &proc_uid_seq_operations); 3088 } 3089 3090 static int proc_gid_map_open(struct inode *inode, struct file *file) 3091 { 3092 return proc_id_map_open(inode, file, &proc_gid_seq_operations); 3093 } 3094 3095 static int proc_projid_map_open(struct inode *inode, struct file *file) 3096 { 3097 return proc_id_map_open(inode, file, &proc_projid_seq_operations); 3098 } 3099 3100 static const struct file_operations proc_uid_map_operations = { 3101 .open = proc_uid_map_open, 3102 .write = proc_uid_map_write, 3103 .read = seq_read, 3104 .llseek = seq_lseek, 3105 .release = proc_id_map_release, 3106 }; 3107 3108 static const struct file_operations proc_gid_map_operations = { 3109 .open = proc_gid_map_open, 3110 .write = proc_gid_map_write, 3111 .read = seq_read, 3112 .llseek = seq_lseek, 3113 .release = proc_id_map_release, 3114 }; 3115 3116 static const struct file_operations proc_projid_map_operations = { 3117 .open = proc_projid_map_open, 3118 .write = proc_projid_map_write, 3119 .read = seq_read, 3120 .llseek = seq_lseek, 3121 .release = proc_id_map_release, 3122 }; 3123 3124 static int proc_setgroups_open(struct inode *inode, struct file *file) 3125 { 3126 struct user_namespace *ns = NULL; 3127 struct task_struct *task; 3128 int ret; 3129 3130 ret = -ESRCH; 3131 task = get_proc_task(inode); 3132 if (task) { 3133 rcu_read_lock(); 3134 ns = get_user_ns(task_cred_xxx(task, user_ns)); 3135 rcu_read_unlock(); 3136 put_task_struct(task); 3137 } 3138 if (!ns) 3139 goto err; 3140 3141 if (file->f_mode & FMODE_WRITE) { 3142 ret = -EACCES; 3143 if (!ns_capable(ns, CAP_SYS_ADMIN)) 3144 goto err_put_ns; 3145 } 3146 3147 ret = single_open(file, &proc_setgroups_show, ns); 3148 if (ret) 3149 goto err_put_ns; 3150 3151 return 0; 3152 err_put_ns: 3153 put_user_ns(ns); 3154 err: 3155 return ret; 3156 } 3157 3158 static int proc_setgroups_release(struct inode *inode, struct file *file) 3159 { 3160 struct seq_file *seq = file->private_data; 3161 struct user_namespace *ns = seq->private; 3162 int ret = single_release(inode, file); 3163 put_user_ns(ns); 3164 return ret; 3165 } 3166 3167 static const struct file_operations proc_setgroups_operations = { 3168 .open = proc_setgroups_open, 3169 .write = proc_setgroups_write, 3170 .read = seq_read, 3171 .llseek = seq_lseek, 3172 .release = proc_setgroups_release, 3173 }; 3174 #endif /* CONFIG_USER_NS */ 3175 3176 static int proc_pid_personality(struct seq_file *m, struct pid_namespace *ns, 3177 struct pid *pid, struct task_struct *task) 3178 { 3179 int err = lock_trace(task); 3180 if (!err) { 3181 seq_printf(m, "%08x\n", task->personality); 3182 unlock_trace(task); 3183 } 3184 return err; 3185 } 3186 3187 #ifdef CONFIG_LIVEPATCH 3188 static int proc_pid_patch_state(struct seq_file *m, struct pid_namespace *ns, 3189 struct pid *pid, struct task_struct *task) 3190 { 3191 seq_printf(m, "%d\n", task->patch_state); 3192 return 0; 3193 } 3194 #endif /* CONFIG_LIVEPATCH */ 3195 3196 #ifdef CONFIG_KSM 3197 static int proc_pid_ksm_merging_pages(struct seq_file *m, struct pid_namespace *ns, 3198 struct pid *pid, struct task_struct *task) 3199 { 3200 struct mm_struct *mm; 3201 3202 mm = get_task_mm(task); 3203 if (mm) { 3204 seq_printf(m, "%lu\n", mm->ksm_merging_pages); 3205 mmput(mm); 3206 } 3207 3208 return 0; 3209 } 3210 static int proc_pid_ksm_stat(struct seq_file *m, struct pid_namespace *ns, 3211 struct pid *pid, struct task_struct *task) 3212 { 3213 struct mm_struct *mm; 3214 3215 mm = get_task_mm(task); 3216 if (mm) { 3217 seq_printf(m, "ksm_rmap_items %lu\n", mm->ksm_rmap_items); 3218 seq_printf(m, "ksm_zero_pages %lu\n", mm->ksm_zero_pages); 3219 seq_printf(m, "ksm_merging_pages %lu\n", mm->ksm_merging_pages); 3220 seq_printf(m, "ksm_process_profit %ld\n", ksm_process_profit(mm)); 3221 mmput(mm); 3222 } 3223 3224 return 0; 3225 } 3226 #endif /* CONFIG_KSM */ 3227 3228 #ifdef CONFIG_STACKLEAK_METRICS 3229 static int proc_stack_depth(struct seq_file *m, struct pid_namespace *ns, 3230 struct pid *pid, struct task_struct *task) 3231 { 3232 unsigned long prev_depth = THREAD_SIZE - 3233 (task->prev_lowest_stack & (THREAD_SIZE - 1)); 3234 unsigned long depth = THREAD_SIZE - 3235 (task->lowest_stack & (THREAD_SIZE - 1)); 3236 3237 seq_printf(m, "previous stack depth: %lu\nstack depth: %lu\n", 3238 prev_depth, depth); 3239 return 0; 3240 } 3241 #endif /* CONFIG_STACKLEAK_METRICS */ 3242 3243 /* 3244 * Thread groups 3245 */ 3246 static const struct file_operations proc_task_operations; 3247 static const struct inode_operations proc_task_inode_operations; 3248 3249 static const struct pid_entry tgid_base_stuff[] = { 3250 DIR("task", S_IRUGO|S_IXUGO, proc_task_inode_operations, proc_task_operations), 3251 DIR("fd", S_IRUSR|S_IXUSR, proc_fd_inode_operations, proc_fd_operations), 3252 DIR("map_files", S_IRUSR|S_IXUSR, proc_map_files_inode_operations, proc_map_files_operations), 3253 DIR("fdinfo", S_IRUGO|S_IXUGO, proc_fdinfo_inode_operations, proc_fdinfo_operations), 3254 DIR("ns", S_IRUSR|S_IXUGO, proc_ns_dir_inode_operations, proc_ns_dir_operations), 3255 #ifdef CONFIG_NET 3256 DIR("net", S_IRUGO|S_IXUGO, proc_net_inode_operations, proc_net_operations), 3257 #endif 3258 REG("environ", S_IRUSR, proc_environ_operations), 3259 REG("auxv", S_IRUSR, proc_auxv_operations), 3260 ONE("status", S_IRUGO, proc_pid_status), 3261 ONE("personality", S_IRUSR, proc_pid_personality), 3262 ONE("limits", S_IRUGO, proc_pid_limits), 3263 #ifdef CONFIG_SCHED_DEBUG 3264 REG("sched", S_IRUGO|S_IWUSR, proc_pid_sched_operations), 3265 #endif 3266 #ifdef CONFIG_SCHED_AUTOGROUP 3267 REG("autogroup", S_IRUGO|S_IWUSR, proc_pid_sched_autogroup_operations), 3268 #endif 3269 #ifdef CONFIG_TIME_NS 3270 REG("timens_offsets", S_IRUGO|S_IWUSR, proc_timens_offsets_operations), 3271 #endif 3272 REG("comm", S_IRUGO|S_IWUSR, proc_pid_set_comm_operations), 3273 #ifdef CONFIG_HAVE_ARCH_TRACEHOOK 3274 ONE("syscall", S_IRUSR, proc_pid_syscall), 3275 #endif 3276 REG("cmdline", S_IRUGO, proc_pid_cmdline_ops), 3277 ONE("stat", S_IRUGO, proc_tgid_stat), 3278 ONE("statm", S_IRUGO, proc_pid_statm), 3279 REG("maps", S_IRUGO, proc_pid_maps_operations), 3280 #ifdef CONFIG_NUMA 3281 REG("numa_maps", S_IRUGO, proc_pid_numa_maps_operations), 3282 #endif 3283 REG("mem", S_IRUSR|S_IWUSR, proc_mem_operations), 3284 LNK("cwd", proc_cwd_link), 3285 LNK("root", proc_root_link), 3286 LNK("exe", proc_exe_link), 3287 REG("mounts", S_IRUGO, proc_mounts_operations), 3288 REG("mountinfo", S_IRUGO, proc_mountinfo_operations), 3289 REG("mountstats", S_IRUSR, proc_mountstats_operations), 3290 #ifdef CONFIG_PROC_PAGE_MONITOR 3291 REG("clear_refs", S_IWUSR, proc_clear_refs_operations), 3292 REG("smaps", S_IRUGO, proc_pid_smaps_operations), 3293 REG("smaps_rollup", S_IRUGO, proc_pid_smaps_rollup_operations), 3294 REG("pagemap", S_IRUSR, proc_pagemap_operations), 3295 #endif 3296 #ifdef CONFIG_SECURITY 3297 DIR("attr", S_IRUGO|S_IXUGO, proc_attr_dir_inode_operations, proc_attr_dir_operations), 3298 #endif 3299 #ifdef CONFIG_KALLSYMS 3300 ONE("wchan", S_IRUGO, proc_pid_wchan), 3301 #endif 3302 #ifdef CONFIG_STACKTRACE 3303 ONE("stack", S_IRUSR, proc_pid_stack), 3304 #endif 3305 #ifdef CONFIG_SCHED_INFO 3306 ONE("schedstat", S_IRUGO, proc_pid_schedstat), 3307 #endif 3308 #ifdef CONFIG_LATENCYTOP 3309 REG("latency", S_IRUGO, proc_lstats_operations), 3310 #endif 3311 #ifdef CONFIG_PROC_PID_CPUSET 3312 ONE("cpuset", S_IRUGO, proc_cpuset_show), 3313 #endif 3314 #ifdef CONFIG_CGROUPS 3315 ONE("cgroup", S_IRUGO, proc_cgroup_show), 3316 #endif 3317 #ifdef CONFIG_PROC_CPU_RESCTRL 3318 ONE("cpu_resctrl_groups", S_IRUGO, proc_resctrl_show), 3319 #endif 3320 ONE("oom_score", S_IRUGO, proc_oom_score), 3321 REG("oom_adj", S_IRUGO|S_IWUSR, proc_oom_adj_operations), 3322 REG("oom_score_adj", S_IRUGO|S_IWUSR, proc_oom_score_adj_operations), 3323 #ifdef CONFIG_AUDIT 3324 REG("loginuid", S_IWUSR|S_IRUGO, proc_loginuid_operations), 3325 REG("sessionid", S_IRUGO, proc_sessionid_operations), 3326 #endif 3327 #ifdef CONFIG_FAULT_INJECTION 3328 REG("make-it-fail", S_IRUGO|S_IWUSR, proc_fault_inject_operations), 3329 REG("fail-nth", 0644, proc_fail_nth_operations), 3330 #endif 3331 #ifdef CONFIG_ELF_CORE 3332 REG("coredump_filter", S_IRUGO|S_IWUSR, proc_coredump_filter_operations), 3333 #endif 3334 #ifdef CONFIG_TASK_IO_ACCOUNTING 3335 ONE("io", S_IRUSR, proc_tgid_io_accounting), 3336 #endif 3337 #ifdef CONFIG_USER_NS 3338 REG("uid_map", S_IRUGO|S_IWUSR, proc_uid_map_operations), 3339 REG("gid_map", S_IRUGO|S_IWUSR, proc_gid_map_operations), 3340 REG("projid_map", S_IRUGO|S_IWUSR, proc_projid_map_operations), 3341 REG("setgroups", S_IRUGO|S_IWUSR, proc_setgroups_operations), 3342 #endif 3343 #if defined(CONFIG_CHECKPOINT_RESTORE) && defined(CONFIG_POSIX_TIMERS) 3344 REG("timers", S_IRUGO, proc_timers_operations), 3345 #endif 3346 REG("timerslack_ns", S_IRUGO|S_IWUGO, proc_pid_set_timerslack_ns_operations), 3347 #ifdef CONFIG_LIVEPATCH 3348 ONE("patch_state", S_IRUSR, proc_pid_patch_state), 3349 #endif 3350 #ifdef CONFIG_STACKLEAK_METRICS 3351 ONE("stack_depth", S_IRUGO, proc_stack_depth), 3352 #endif 3353 #ifdef CONFIG_PROC_PID_ARCH_STATUS 3354 ONE("arch_status", S_IRUGO, proc_pid_arch_status), 3355 #endif 3356 #ifdef CONFIG_SECCOMP_CACHE_DEBUG 3357 ONE("seccomp_cache", S_IRUSR, proc_pid_seccomp_cache), 3358 #endif 3359 #ifdef CONFIG_KSM 3360 ONE("ksm_merging_pages", S_IRUSR, proc_pid_ksm_merging_pages), 3361 ONE("ksm_stat", S_IRUSR, proc_pid_ksm_stat), 3362 #endif 3363 }; 3364 3365 static int proc_tgid_base_readdir(struct file *file, struct dir_context *ctx) 3366 { 3367 return proc_pident_readdir(file, ctx, 3368 tgid_base_stuff, ARRAY_SIZE(tgid_base_stuff)); 3369 } 3370 3371 static const struct file_operations proc_tgid_base_operations = { 3372 .read = generic_read_dir, 3373 .iterate_shared = proc_tgid_base_readdir, 3374 .llseek = generic_file_llseek, 3375 }; 3376 3377 struct pid *tgid_pidfd_to_pid(const struct file *file) 3378 { 3379 if (file->f_op != &proc_tgid_base_operations) 3380 return ERR_PTR(-EBADF); 3381 3382 return proc_pid(file_inode(file)); 3383 } 3384 3385 static struct dentry *proc_tgid_base_lookup(struct inode *dir, struct dentry *dentry, unsigned int flags) 3386 { 3387 return proc_pident_lookup(dir, dentry, 3388 tgid_base_stuff, 3389 tgid_base_stuff + ARRAY_SIZE(tgid_base_stuff)); 3390 } 3391 3392 static const struct inode_operations proc_tgid_base_inode_operations = { 3393 .lookup = proc_tgid_base_lookup, 3394 .getattr = pid_getattr, 3395 .setattr = proc_setattr, 3396 .permission = proc_pid_permission, 3397 }; 3398 3399 /** 3400 * proc_flush_pid - Remove dcache entries for @pid from the /proc dcache. 3401 * @pid: pid that should be flushed. 3402 * 3403 * This function walks a list of inodes (that belong to any proc 3404 * filesystem) that are attached to the pid and flushes them from 3405 * the dentry cache. 3406 * 3407 * It is safe and reasonable to cache /proc entries for a task until 3408 * that task exits. After that they just clog up the dcache with 3409 * useless entries, possibly causing useful dcache entries to be 3410 * flushed instead. This routine is provided to flush those useless 3411 * dcache entries when a process is reaped. 3412 * 3413 * NOTE: This routine is just an optimization so it does not guarantee 3414 * that no dcache entries will exist after a process is reaped 3415 * it just makes it very unlikely that any will persist. 3416 */ 3417 3418 void proc_flush_pid(struct pid *pid) 3419 { 3420 proc_invalidate_siblings_dcache(&pid->inodes, &pid->lock); 3421 } 3422 3423 static struct dentry *proc_pid_instantiate(struct dentry * dentry, 3424 struct task_struct *task, const void *ptr) 3425 { 3426 struct inode *inode; 3427 3428 inode = proc_pid_make_base_inode(dentry->d_sb, task, 3429 S_IFDIR | S_IRUGO | S_IXUGO); 3430 if (!inode) 3431 return ERR_PTR(-ENOENT); 3432 3433 inode->i_op = &proc_tgid_base_inode_operations; 3434 inode->i_fop = &proc_tgid_base_operations; 3435 inode->i_flags|=S_IMMUTABLE; 3436 3437 set_nlink(inode, nlink_tgid); 3438 pid_update_inode(task, inode); 3439 3440 d_set_d_op(dentry, &pid_dentry_operations); 3441 return d_splice_alias(inode, dentry); 3442 } 3443 3444 struct dentry *proc_pid_lookup(struct dentry *dentry, unsigned int flags) 3445 { 3446 struct task_struct *task; 3447 unsigned tgid; 3448 struct proc_fs_info *fs_info; 3449 struct pid_namespace *ns; 3450 struct dentry *result = ERR_PTR(-ENOENT); 3451 3452 tgid = name_to_int(&dentry->d_name); 3453 if (tgid == ~0U) 3454 goto out; 3455 3456 fs_info = proc_sb_info(dentry->d_sb); 3457 ns = fs_info->pid_ns; 3458 rcu_read_lock(); 3459 task = find_task_by_pid_ns(tgid, ns); 3460 if (task) 3461 get_task_struct(task); 3462 rcu_read_unlock(); 3463 if (!task) 3464 goto out; 3465 3466 /* Limit procfs to only ptraceable tasks */ 3467 if (fs_info->hide_pid == HIDEPID_NOT_PTRACEABLE) { 3468 if (!has_pid_permissions(fs_info, task, HIDEPID_NO_ACCESS)) 3469 goto out_put_task; 3470 } 3471 3472 result = proc_pid_instantiate(dentry, task, NULL); 3473 out_put_task: 3474 put_task_struct(task); 3475 out: 3476 return result; 3477 } 3478 3479 /* 3480 * Find the first task with tgid >= tgid 3481 * 3482 */ 3483 struct tgid_iter { 3484 unsigned int tgid; 3485 struct task_struct *task; 3486 }; 3487 static struct tgid_iter next_tgid(struct pid_namespace *ns, struct tgid_iter iter) 3488 { 3489 struct pid *pid; 3490 3491 if (iter.task) 3492 put_task_struct(iter.task); 3493 rcu_read_lock(); 3494 retry: 3495 iter.task = NULL; 3496 pid = find_ge_pid(iter.tgid, ns); 3497 if (pid) { 3498 iter.tgid = pid_nr_ns(pid, ns); 3499 iter.task = pid_task(pid, PIDTYPE_TGID); 3500 if (!iter.task) { 3501 iter.tgid += 1; 3502 goto retry; 3503 } 3504 get_task_struct(iter.task); 3505 } 3506 rcu_read_unlock(); 3507 return iter; 3508 } 3509 3510 #define TGID_OFFSET (FIRST_PROCESS_ENTRY + 2) 3511 3512 /* for the /proc/ directory itself, after non-process stuff has been done */ 3513 int proc_pid_readdir(struct file *file, struct dir_context *ctx) 3514 { 3515 struct tgid_iter iter; 3516 struct proc_fs_info *fs_info = proc_sb_info(file_inode(file)->i_sb); 3517 struct pid_namespace *ns = proc_pid_ns(file_inode(file)->i_sb); 3518 loff_t pos = ctx->pos; 3519 3520 if (pos >= PID_MAX_LIMIT + TGID_OFFSET) 3521 return 0; 3522 3523 if (pos == TGID_OFFSET - 2) { 3524 struct inode *inode = d_inode(fs_info->proc_self); 3525 if (!dir_emit(ctx, "self", 4, inode->i_ino, DT_LNK)) 3526 return 0; 3527 ctx->pos = pos = pos + 1; 3528 } 3529 if (pos == TGID_OFFSET - 1) { 3530 struct inode *inode = d_inode(fs_info->proc_thread_self); 3531 if (!dir_emit(ctx, "thread-self", 11, inode->i_ino, DT_LNK)) 3532 return 0; 3533 ctx->pos = pos = pos + 1; 3534 } 3535 iter.tgid = pos - TGID_OFFSET; 3536 iter.task = NULL; 3537 for (iter = next_tgid(ns, iter); 3538 iter.task; 3539 iter.tgid += 1, iter = next_tgid(ns, iter)) { 3540 char name[10 + 1]; 3541 unsigned int len; 3542 3543 cond_resched(); 3544 if (!has_pid_permissions(fs_info, iter.task, HIDEPID_INVISIBLE)) 3545 continue; 3546 3547 len = snprintf(name, sizeof(name), "%u", iter.tgid); 3548 ctx->pos = iter.tgid + TGID_OFFSET; 3549 if (!proc_fill_cache(file, ctx, name, len, 3550 proc_pid_instantiate, iter.task, NULL)) { 3551 put_task_struct(iter.task); 3552 return 0; 3553 } 3554 } 3555 ctx->pos = PID_MAX_LIMIT + TGID_OFFSET; 3556 return 0; 3557 } 3558 3559 /* 3560 * proc_tid_comm_permission is a special permission function exclusively 3561 * used for the node /proc/<pid>/task/<tid>/comm. 3562 * It bypasses generic permission checks in the case where a task of the same 3563 * task group attempts to access the node. 3564 * The rationale behind this is that glibc and bionic access this node for 3565 * cross thread naming (pthread_set/getname_np(!self)). However, if 3566 * PR_SET_DUMPABLE gets set to 0 this node among others becomes uid=0 gid=0, 3567 * which locks out the cross thread naming implementation. 3568 * This function makes sure that the node is always accessible for members of 3569 * same thread group. 3570 */ 3571 static int proc_tid_comm_permission(struct mnt_idmap *idmap, 3572 struct inode *inode, int mask) 3573 { 3574 bool is_same_tgroup; 3575 struct task_struct *task; 3576 3577 task = get_proc_task(inode); 3578 if (!task) 3579 return -ESRCH; 3580 is_same_tgroup = same_thread_group(current, task); 3581 put_task_struct(task); 3582 3583 if (likely(is_same_tgroup && !(mask & MAY_EXEC))) { 3584 /* This file (/proc/<pid>/task/<tid>/comm) can always be 3585 * read or written by the members of the corresponding 3586 * thread group. 3587 */ 3588 return 0; 3589 } 3590 3591 return generic_permission(&nop_mnt_idmap, inode, mask); 3592 } 3593 3594 static const struct inode_operations proc_tid_comm_inode_operations = { 3595 .setattr = proc_setattr, 3596 .permission = proc_tid_comm_permission, 3597 }; 3598 3599 /* 3600 * Tasks 3601 */ 3602 static const struct pid_entry tid_base_stuff[] = { 3603 DIR("fd", S_IRUSR|S_IXUSR, proc_fd_inode_operations, proc_fd_operations), 3604 DIR("fdinfo", S_IRUGO|S_IXUGO, proc_fdinfo_inode_operations, proc_fdinfo_operations), 3605 DIR("ns", S_IRUSR|S_IXUGO, proc_ns_dir_inode_operations, proc_ns_dir_operations), 3606 #ifdef CONFIG_NET 3607 DIR("net", S_IRUGO|S_IXUGO, proc_net_inode_operations, proc_net_operations), 3608 #endif 3609 REG("environ", S_IRUSR, proc_environ_operations), 3610 REG("auxv", S_IRUSR, proc_auxv_operations), 3611 ONE("status", S_IRUGO, proc_pid_status), 3612 ONE("personality", S_IRUSR, proc_pid_personality), 3613 ONE("limits", S_IRUGO, proc_pid_limits), 3614 #ifdef CONFIG_SCHED_DEBUG 3615 REG("sched", S_IRUGO|S_IWUSR, proc_pid_sched_operations), 3616 #endif 3617 NOD("comm", S_IFREG|S_IRUGO|S_IWUSR, 3618 &proc_tid_comm_inode_operations, 3619 &proc_pid_set_comm_operations, {}), 3620 #ifdef CONFIG_HAVE_ARCH_TRACEHOOK 3621 ONE("syscall", S_IRUSR, proc_pid_syscall), 3622 #endif 3623 REG("cmdline", S_IRUGO, proc_pid_cmdline_ops), 3624 ONE("stat", S_IRUGO, proc_tid_stat), 3625 ONE("statm", S_IRUGO, proc_pid_statm), 3626 REG("maps", S_IRUGO, proc_pid_maps_operations), 3627 #ifdef CONFIG_PROC_CHILDREN 3628 REG("children", S_IRUGO, proc_tid_children_operations), 3629 #endif 3630 #ifdef CONFIG_NUMA 3631 REG("numa_maps", S_IRUGO, proc_pid_numa_maps_operations), 3632 #endif 3633 REG("mem", S_IRUSR|S_IWUSR, proc_mem_operations), 3634 LNK("cwd", proc_cwd_link), 3635 LNK("root", proc_root_link), 3636 LNK("exe", proc_exe_link), 3637 REG("mounts", S_IRUGO, proc_mounts_operations), 3638 REG("mountinfo", S_IRUGO, proc_mountinfo_operations), 3639 #ifdef CONFIG_PROC_PAGE_MONITOR 3640 REG("clear_refs", S_IWUSR, proc_clear_refs_operations), 3641 REG("smaps", S_IRUGO, proc_pid_smaps_operations), 3642 REG("smaps_rollup", S_IRUGO, proc_pid_smaps_rollup_operations), 3643 REG("pagemap", S_IRUSR, proc_pagemap_operations), 3644 #endif 3645 #ifdef CONFIG_SECURITY 3646 DIR("attr", S_IRUGO|S_IXUGO, proc_attr_dir_inode_operations, proc_attr_dir_operations), 3647 #endif 3648 #ifdef CONFIG_KALLSYMS 3649 ONE("wchan", S_IRUGO, proc_pid_wchan), 3650 #endif 3651 #ifdef CONFIG_STACKTRACE 3652 ONE("stack", S_IRUSR, proc_pid_stack), 3653 #endif 3654 #ifdef CONFIG_SCHED_INFO 3655 ONE("schedstat", S_IRUGO, proc_pid_schedstat), 3656 #endif 3657 #ifdef CONFIG_LATENCYTOP 3658 REG("latency", S_IRUGO, proc_lstats_operations), 3659 #endif 3660 #ifdef CONFIG_PROC_PID_CPUSET 3661 ONE("cpuset", S_IRUGO, proc_cpuset_show), 3662 #endif 3663 #ifdef CONFIG_CGROUPS 3664 ONE("cgroup", S_IRUGO, proc_cgroup_show), 3665 #endif 3666 #ifdef CONFIG_PROC_CPU_RESCTRL 3667 ONE("cpu_resctrl_groups", S_IRUGO, proc_resctrl_show), 3668 #endif 3669 ONE("oom_score", S_IRUGO, proc_oom_score), 3670 REG("oom_adj", S_IRUGO|S_IWUSR, proc_oom_adj_operations), 3671 REG("oom_score_adj", S_IRUGO|S_IWUSR, proc_oom_score_adj_operations), 3672 #ifdef CONFIG_AUDIT 3673 REG("loginuid", S_IWUSR|S_IRUGO, proc_loginuid_operations), 3674 REG("sessionid", S_IRUGO, proc_sessionid_operations), 3675 #endif 3676 #ifdef CONFIG_FAULT_INJECTION 3677 REG("make-it-fail", S_IRUGO|S_IWUSR, proc_fault_inject_operations), 3678 REG("fail-nth", 0644, proc_fail_nth_operations), 3679 #endif 3680 #ifdef CONFIG_TASK_IO_ACCOUNTING 3681 ONE("io", S_IRUSR, proc_tid_io_accounting), 3682 #endif 3683 #ifdef CONFIG_USER_NS 3684 REG("uid_map", S_IRUGO|S_IWUSR, proc_uid_map_operations), 3685 REG("gid_map", S_IRUGO|S_IWUSR, proc_gid_map_operations), 3686 REG("projid_map", S_IRUGO|S_IWUSR, proc_projid_map_operations), 3687 REG("setgroups", S_IRUGO|S_IWUSR, proc_setgroups_operations), 3688 #endif 3689 #ifdef CONFIG_LIVEPATCH 3690 ONE("patch_state", S_IRUSR, proc_pid_patch_state), 3691 #endif 3692 #ifdef CONFIG_PROC_PID_ARCH_STATUS 3693 ONE("arch_status", S_IRUGO, proc_pid_arch_status), 3694 #endif 3695 #ifdef CONFIG_SECCOMP_CACHE_DEBUG 3696 ONE("seccomp_cache", S_IRUSR, proc_pid_seccomp_cache), 3697 #endif 3698 #ifdef CONFIG_KSM 3699 ONE("ksm_merging_pages", S_IRUSR, proc_pid_ksm_merging_pages), 3700 ONE("ksm_stat", S_IRUSR, proc_pid_ksm_stat), 3701 #endif 3702 }; 3703 3704 static int proc_tid_base_readdir(struct file *file, struct dir_context *ctx) 3705 { 3706 return proc_pident_readdir(file, ctx, 3707 tid_base_stuff, ARRAY_SIZE(tid_base_stuff)); 3708 } 3709 3710 static struct dentry *proc_tid_base_lookup(struct inode *dir, struct dentry *dentry, unsigned int flags) 3711 { 3712 return proc_pident_lookup(dir, dentry, 3713 tid_base_stuff, 3714 tid_base_stuff + ARRAY_SIZE(tid_base_stuff)); 3715 } 3716 3717 static const struct file_operations proc_tid_base_operations = { 3718 .read = generic_read_dir, 3719 .iterate_shared = proc_tid_base_readdir, 3720 .llseek = generic_file_llseek, 3721 }; 3722 3723 static const struct inode_operations proc_tid_base_inode_operations = { 3724 .lookup = proc_tid_base_lookup, 3725 .getattr = pid_getattr, 3726 .setattr = proc_setattr, 3727 }; 3728 3729 static struct dentry *proc_task_instantiate(struct dentry *dentry, 3730 struct task_struct *task, const void *ptr) 3731 { 3732 struct inode *inode; 3733 inode = proc_pid_make_base_inode(dentry->d_sb, task, 3734 S_IFDIR | S_IRUGO | S_IXUGO); 3735 if (!inode) 3736 return ERR_PTR(-ENOENT); 3737 3738 inode->i_op = &proc_tid_base_inode_operations; 3739 inode->i_fop = &proc_tid_base_operations; 3740 inode->i_flags |= S_IMMUTABLE; 3741 3742 set_nlink(inode, nlink_tid); 3743 pid_update_inode(task, inode); 3744 3745 d_set_d_op(dentry, &pid_dentry_operations); 3746 return d_splice_alias(inode, dentry); 3747 } 3748 3749 static struct dentry *proc_task_lookup(struct inode *dir, struct dentry * dentry, unsigned int flags) 3750 { 3751 struct task_struct *task; 3752 struct task_struct *leader = get_proc_task(dir); 3753 unsigned tid; 3754 struct proc_fs_info *fs_info; 3755 struct pid_namespace *ns; 3756 struct dentry *result = ERR_PTR(-ENOENT); 3757 3758 if (!leader) 3759 goto out_no_task; 3760 3761 tid = name_to_int(&dentry->d_name); 3762 if (tid == ~0U) 3763 goto out; 3764 3765 fs_info = proc_sb_info(dentry->d_sb); 3766 ns = fs_info->pid_ns; 3767 rcu_read_lock(); 3768 task = find_task_by_pid_ns(tid, ns); 3769 if (task) 3770 get_task_struct(task); 3771 rcu_read_unlock(); 3772 if (!task) 3773 goto out; 3774 if (!same_thread_group(leader, task)) 3775 goto out_drop_task; 3776 3777 result = proc_task_instantiate(dentry, task, NULL); 3778 out_drop_task: 3779 put_task_struct(task); 3780 out: 3781 put_task_struct(leader); 3782 out_no_task: 3783 return result; 3784 } 3785 3786 /* 3787 * Find the first tid of a thread group to return to user space. 3788 * 3789 * Usually this is just the thread group leader, but if the users 3790 * buffer was too small or there was a seek into the middle of the 3791 * directory we have more work todo. 3792 * 3793 * In the case of a short read we start with find_task_by_pid. 3794 * 3795 * In the case of a seek we start with the leader and walk nr 3796 * threads past it. 3797 */ 3798 static struct task_struct *first_tid(struct pid *pid, int tid, loff_t f_pos, 3799 struct pid_namespace *ns) 3800 { 3801 struct task_struct *pos, *task; 3802 unsigned long nr = f_pos; 3803 3804 if (nr != f_pos) /* 32bit overflow? */ 3805 return NULL; 3806 3807 rcu_read_lock(); 3808 task = pid_task(pid, PIDTYPE_PID); 3809 if (!task) 3810 goto fail; 3811 3812 /* Attempt to start with the tid of a thread */ 3813 if (tid && nr) { 3814 pos = find_task_by_pid_ns(tid, ns); 3815 if (pos && same_thread_group(pos, task)) 3816 goto found; 3817 } 3818 3819 /* If nr exceeds the number of threads there is nothing todo */ 3820 if (nr >= get_nr_threads(task)) 3821 goto fail; 3822 3823 /* If we haven't found our starting place yet start 3824 * with the leader and walk nr threads forward. 3825 */ 3826 for_each_thread(task, pos) { 3827 if (!nr--) 3828 goto found; 3829 } 3830 fail: 3831 pos = NULL; 3832 goto out; 3833 found: 3834 get_task_struct(pos); 3835 out: 3836 rcu_read_unlock(); 3837 return pos; 3838 } 3839 3840 /* 3841 * Find the next thread in the thread list. 3842 * Return NULL if there is an error or no next thread. 3843 * 3844 * The reference to the input task_struct is released. 3845 */ 3846 static struct task_struct *next_tid(struct task_struct *start) 3847 { 3848 struct task_struct *pos = NULL; 3849 rcu_read_lock(); 3850 if (pid_alive(start)) { 3851 pos = __next_thread(start); 3852 if (pos) 3853 get_task_struct(pos); 3854 } 3855 rcu_read_unlock(); 3856 put_task_struct(start); 3857 return pos; 3858 } 3859 3860 /* for the /proc/TGID/task/ directories */ 3861 static int proc_task_readdir(struct file *file, struct dir_context *ctx) 3862 { 3863 struct inode *inode = file_inode(file); 3864 struct task_struct *task; 3865 struct pid_namespace *ns; 3866 int tid; 3867 3868 if (proc_inode_is_dead(inode)) 3869 return -ENOENT; 3870 3871 if (!dir_emit_dots(file, ctx)) 3872 return 0; 3873 3874 /* f_version caches the tgid value that the last readdir call couldn't 3875 * return. lseek aka telldir automagically resets f_version to 0. 3876 */ 3877 ns = proc_pid_ns(inode->i_sb); 3878 tid = (int)file->f_version; 3879 file->f_version = 0; 3880 for (task = first_tid(proc_pid(inode), tid, ctx->pos - 2, ns); 3881 task; 3882 task = next_tid(task), ctx->pos++) { 3883 char name[10 + 1]; 3884 unsigned int len; 3885 3886 tid = task_pid_nr_ns(task, ns); 3887 if (!tid) 3888 continue; /* The task has just exited. */ 3889 len = snprintf(name, sizeof(name), "%u", tid); 3890 if (!proc_fill_cache(file, ctx, name, len, 3891 proc_task_instantiate, task, NULL)) { 3892 /* returning this tgid failed, save it as the first 3893 * pid for the next readir call */ 3894 file->f_version = (u64)tid; 3895 put_task_struct(task); 3896 break; 3897 } 3898 } 3899 3900 return 0; 3901 } 3902 3903 static int proc_task_getattr(struct mnt_idmap *idmap, 3904 const struct path *path, struct kstat *stat, 3905 u32 request_mask, unsigned int query_flags) 3906 { 3907 struct inode *inode = d_inode(path->dentry); 3908 struct task_struct *p = get_proc_task(inode); 3909 generic_fillattr(&nop_mnt_idmap, request_mask, inode, stat); 3910 3911 if (p) { 3912 stat->nlink += get_nr_threads(p); 3913 put_task_struct(p); 3914 } 3915 3916 return 0; 3917 } 3918 3919 static const struct inode_operations proc_task_inode_operations = { 3920 .lookup = proc_task_lookup, 3921 .getattr = proc_task_getattr, 3922 .setattr = proc_setattr, 3923 .permission = proc_pid_permission, 3924 }; 3925 3926 static const struct file_operations proc_task_operations = { 3927 .read = generic_read_dir, 3928 .iterate_shared = proc_task_readdir, 3929 .llseek = generic_file_llseek, 3930 }; 3931 3932 void __init set_proc_pid_nlink(void) 3933 { 3934 nlink_tid = pid_entry_nlink(tid_base_stuff, ARRAY_SIZE(tid_base_stuff)); 3935 nlink_tgid = pid_entry_nlink(tgid_base_stuff, ARRAY_SIZE(tgid_base_stuff)); 3936 } 3937