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/string.h> 63 #include <linux/seq_file.h> 64 #include <linux/namei.h> 65 #include <linux/mnt_namespace.h> 66 #include <linux/mm.h> 67 #include <linux/swap.h> 68 #include <linux/rcupdate.h> 69 #include <linux/kallsyms.h> 70 #include <linux/stacktrace.h> 71 #include <linux/resource.h> 72 #include <linux/module.h> 73 #include <linux/mount.h> 74 #include <linux/security.h> 75 #include <linux/ptrace.h> 76 #include <linux/tracehook.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/flex_array.h> 96 #include <linux/posix-timers.h> 97 #include <trace/events/oom.h> 98 #include "internal.h" 99 #include "fd.h" 100 101 #include "../../lib/kstrtox.h" 102 103 /* NOTE: 104 * Implementing inode permission operations in /proc is almost 105 * certainly an error. Permission checks need to happen during 106 * each system call not at open time. The reason is that most of 107 * what we wish to check for permissions in /proc varies at runtime. 108 * 109 * The classic example of a problem is opening file descriptors 110 * in /proc for a task before it execs a suid executable. 111 */ 112 113 static u8 nlink_tid __ro_after_init; 114 static u8 nlink_tgid __ro_after_init; 115 116 struct pid_entry { 117 const char *name; 118 unsigned int len; 119 umode_t mode; 120 const struct inode_operations *iop; 121 const struct file_operations *fop; 122 union proc_op op; 123 }; 124 125 #define NOD(NAME, MODE, IOP, FOP, OP) { \ 126 .name = (NAME), \ 127 .len = sizeof(NAME) - 1, \ 128 .mode = MODE, \ 129 .iop = IOP, \ 130 .fop = FOP, \ 131 .op = OP, \ 132 } 133 134 #define DIR(NAME, MODE, iops, fops) \ 135 NOD(NAME, (S_IFDIR|(MODE)), &iops, &fops, {} ) 136 #define LNK(NAME, get_link) \ 137 NOD(NAME, (S_IFLNK|S_IRWXUGO), \ 138 &proc_pid_link_inode_operations, NULL, \ 139 { .proc_get_link = get_link } ) 140 #define REG(NAME, MODE, fops) \ 141 NOD(NAME, (S_IFREG|(MODE)), NULL, &fops, {}) 142 #define ONE(NAME, MODE, show) \ 143 NOD(NAME, (S_IFREG|(MODE)), \ 144 NULL, &proc_single_file_operations, \ 145 { .proc_show = show } ) 146 147 /* 148 * Count the number of hardlinks for the pid_entry table, excluding the . 149 * and .. links. 150 */ 151 static unsigned int __init pid_entry_nlink(const struct pid_entry *entries, 152 unsigned int n) 153 { 154 unsigned int i; 155 unsigned int count; 156 157 count = 2; 158 for (i = 0; i < n; ++i) { 159 if (S_ISDIR(entries[i].mode)) 160 ++count; 161 } 162 163 return count; 164 } 165 166 static int get_task_root(struct task_struct *task, struct path *root) 167 { 168 int result = -ENOENT; 169 170 task_lock(task); 171 if (task->fs) { 172 get_fs_root(task->fs, root); 173 result = 0; 174 } 175 task_unlock(task); 176 return result; 177 } 178 179 static int proc_cwd_link(struct dentry *dentry, struct path *path) 180 { 181 struct task_struct *task = get_proc_task(d_inode(dentry)); 182 int result = -ENOENT; 183 184 if (task) { 185 task_lock(task); 186 if (task->fs) { 187 get_fs_pwd(task->fs, path); 188 result = 0; 189 } 190 task_unlock(task); 191 put_task_struct(task); 192 } 193 return result; 194 } 195 196 static int proc_root_link(struct dentry *dentry, struct path *path) 197 { 198 struct task_struct *task = get_proc_task(d_inode(dentry)); 199 int result = -ENOENT; 200 201 if (task) { 202 result = get_task_root(task, path); 203 put_task_struct(task); 204 } 205 return result; 206 } 207 208 static ssize_t proc_pid_cmdline_read(struct file *file, char __user *buf, 209 size_t _count, loff_t *pos) 210 { 211 struct task_struct *tsk; 212 struct mm_struct *mm; 213 char *page; 214 unsigned long count = _count; 215 unsigned long arg_start, arg_end, env_start, env_end; 216 unsigned long len1, len2; 217 char __user *buf0 = buf; 218 struct { 219 unsigned long p; 220 unsigned long len; 221 } cmdline[2]; 222 char c; 223 int rv; 224 225 BUG_ON(*pos < 0); 226 227 tsk = get_proc_task(file_inode(file)); 228 if (!tsk) 229 return -ESRCH; 230 mm = get_task_mm(tsk); 231 put_task_struct(tsk); 232 if (!mm) 233 return 0; 234 /* Check if process spawned far enough to have cmdline. */ 235 if (!mm->env_end) { 236 rv = 0; 237 goto out_mmput; 238 } 239 240 page = (char *)__get_free_page(GFP_KERNEL); 241 if (!page) { 242 rv = -ENOMEM; 243 goto out_mmput; 244 } 245 246 spin_lock(&mm->arg_lock); 247 arg_start = mm->arg_start; 248 arg_end = mm->arg_end; 249 env_start = mm->env_start; 250 env_end = mm->env_end; 251 spin_unlock(&mm->arg_lock); 252 253 BUG_ON(arg_start > arg_end); 254 BUG_ON(env_start > env_end); 255 256 len1 = arg_end - arg_start; 257 len2 = env_end - env_start; 258 259 /* Empty ARGV. */ 260 if (len1 == 0) 261 goto end; 262 263 /* 264 * Inherently racy -- command line shares address space 265 * with code and data. 266 */ 267 if (access_remote_vm(mm, arg_end - 1, &c, 1, FOLL_ANON) != 1) 268 goto end; 269 270 cmdline[0].p = arg_start; 271 cmdline[0].len = len1; 272 if (c == '\0') { 273 /* Command line (set of strings) occupies whole ARGV. */ 274 cmdline[1].len = 0; 275 } else { 276 /* 277 * Command line (1 string) occupies ARGV and 278 * extends into ENVP. 279 */ 280 cmdline[1].p = env_start; 281 cmdline[1].len = len2; 282 } 283 284 { 285 loff_t pos1 = *pos; 286 unsigned int i; 287 288 i = 0; 289 while (i < 2 && pos1 >= cmdline[i].len) { 290 pos1 -= cmdline[i].len; 291 i++; 292 } 293 while (i < 2) { 294 unsigned long p; 295 unsigned long len; 296 297 p = cmdline[i].p + pos1; 298 len = cmdline[i].len - pos1; 299 while (count > 0 && len > 0) { 300 unsigned int nr_read, nr_write; 301 302 nr_read = min3(count, len, PAGE_SIZE); 303 nr_read = access_remote_vm(mm, p, page, nr_read, FOLL_ANON); 304 if (nr_read == 0) 305 goto end; 306 307 /* 308 * Command line can be shorter than whole ARGV 309 * even if last "marker" byte says it is not. 310 */ 311 if (c == '\0') 312 nr_write = nr_read; 313 else 314 nr_write = strnlen(page, nr_read); 315 316 if (copy_to_user(buf, page, nr_write)) { 317 rv = -EFAULT; 318 goto out_free_page; 319 } 320 321 p += nr_write; 322 len -= nr_write; 323 buf += nr_write; 324 count -= nr_write; 325 326 if (nr_write < nr_read) 327 goto end; 328 } 329 330 /* Only first chunk can be read partially. */ 331 pos1 = 0; 332 i++; 333 } 334 } 335 336 end: 337 *pos += buf - buf0; 338 rv = buf - buf0; 339 out_free_page: 340 free_page((unsigned long)page); 341 out_mmput: 342 mmput(mm); 343 return rv; 344 } 345 346 static const struct file_operations proc_pid_cmdline_ops = { 347 .read = proc_pid_cmdline_read, 348 .llseek = generic_file_llseek, 349 }; 350 351 #ifdef CONFIG_KALLSYMS 352 /* 353 * Provides a wchan file via kallsyms in a proper one-value-per-file format. 354 * Returns the resolved symbol. If that fails, simply return the address. 355 */ 356 static int proc_pid_wchan(struct seq_file *m, struct pid_namespace *ns, 357 struct pid *pid, struct task_struct *task) 358 { 359 unsigned long wchan; 360 char symname[KSYM_NAME_LEN]; 361 362 if (!ptrace_may_access(task, PTRACE_MODE_READ_FSCREDS)) 363 goto print0; 364 365 wchan = get_wchan(task); 366 if (wchan && !lookup_symbol_name(wchan, symname)) { 367 seq_puts(m, symname); 368 return 0; 369 } 370 371 print0: 372 seq_putc(m, '0'); 373 return 0; 374 } 375 #endif /* CONFIG_KALLSYMS */ 376 377 static int lock_trace(struct task_struct *task) 378 { 379 int err = mutex_lock_killable(&task->signal->cred_guard_mutex); 380 if (err) 381 return err; 382 if (!ptrace_may_access(task, PTRACE_MODE_ATTACH_FSCREDS)) { 383 mutex_unlock(&task->signal->cred_guard_mutex); 384 return -EPERM; 385 } 386 return 0; 387 } 388 389 static void unlock_trace(struct task_struct *task) 390 { 391 mutex_unlock(&task->signal->cred_guard_mutex); 392 } 393 394 #ifdef CONFIG_STACKTRACE 395 396 #define MAX_STACK_TRACE_DEPTH 64 397 398 static int proc_pid_stack(struct seq_file *m, struct pid_namespace *ns, 399 struct pid *pid, struct task_struct *task) 400 { 401 struct stack_trace trace; 402 unsigned long *entries; 403 int err; 404 405 entries = kmalloc(MAX_STACK_TRACE_DEPTH * sizeof(*entries), GFP_KERNEL); 406 if (!entries) 407 return -ENOMEM; 408 409 trace.nr_entries = 0; 410 trace.max_entries = MAX_STACK_TRACE_DEPTH; 411 trace.entries = entries; 412 trace.skip = 0; 413 414 err = lock_trace(task); 415 if (!err) { 416 unsigned int i; 417 418 save_stack_trace_tsk(task, &trace); 419 420 for (i = 0; i < trace.nr_entries; i++) { 421 seq_printf(m, "[<0>] %pB\n", (void *)entries[i]); 422 } 423 unlock_trace(task); 424 } 425 kfree(entries); 426 427 return err; 428 } 429 #endif 430 431 #ifdef CONFIG_SCHED_INFO 432 /* 433 * Provides /proc/PID/schedstat 434 */ 435 static int proc_pid_schedstat(struct seq_file *m, struct pid_namespace *ns, 436 struct pid *pid, struct task_struct *task) 437 { 438 if (unlikely(!sched_info_on())) 439 seq_printf(m, "0 0 0\n"); 440 else 441 seq_printf(m, "%llu %llu %lu\n", 442 (unsigned long long)task->se.sum_exec_runtime, 443 (unsigned long long)task->sched_info.run_delay, 444 task->sched_info.pcount); 445 446 return 0; 447 } 448 #endif 449 450 #ifdef CONFIG_LATENCYTOP 451 static int lstats_show_proc(struct seq_file *m, void *v) 452 { 453 int i; 454 struct inode *inode = m->private; 455 struct task_struct *task = get_proc_task(inode); 456 457 if (!task) 458 return -ESRCH; 459 seq_puts(m, "Latency Top version : v0.1\n"); 460 for (i = 0; i < 32; i++) { 461 struct latency_record *lr = &task->latency_record[i]; 462 if (lr->backtrace[0]) { 463 int q; 464 seq_printf(m, "%i %li %li", 465 lr->count, lr->time, lr->max); 466 for (q = 0; q < LT_BACKTRACEDEPTH; q++) { 467 unsigned long bt = lr->backtrace[q]; 468 if (!bt) 469 break; 470 if (bt == ULONG_MAX) 471 break; 472 seq_printf(m, " %ps", (void *)bt); 473 } 474 seq_putc(m, '\n'); 475 } 476 477 } 478 put_task_struct(task); 479 return 0; 480 } 481 482 static int lstats_open(struct inode *inode, struct file *file) 483 { 484 return single_open(file, lstats_show_proc, inode); 485 } 486 487 static ssize_t lstats_write(struct file *file, const char __user *buf, 488 size_t count, loff_t *offs) 489 { 490 struct task_struct *task = get_proc_task(file_inode(file)); 491 492 if (!task) 493 return -ESRCH; 494 clear_all_latency_tracing(task); 495 put_task_struct(task); 496 497 return count; 498 } 499 500 static const struct file_operations proc_lstats_operations = { 501 .open = lstats_open, 502 .read = seq_read, 503 .write = lstats_write, 504 .llseek = seq_lseek, 505 .release = single_release, 506 }; 507 508 #endif 509 510 static int proc_oom_score(struct seq_file *m, struct pid_namespace *ns, 511 struct pid *pid, struct task_struct *task) 512 { 513 unsigned long totalpages = totalram_pages + total_swap_pages; 514 unsigned long points = 0; 515 516 points = oom_badness(task, NULL, NULL, totalpages) * 517 1000 / totalpages; 518 seq_printf(m, "%lu\n", points); 519 520 return 0; 521 } 522 523 struct limit_names { 524 const char *name; 525 const char *unit; 526 }; 527 528 static const struct limit_names lnames[RLIM_NLIMITS] = { 529 [RLIMIT_CPU] = {"Max cpu time", "seconds"}, 530 [RLIMIT_FSIZE] = {"Max file size", "bytes"}, 531 [RLIMIT_DATA] = {"Max data size", "bytes"}, 532 [RLIMIT_STACK] = {"Max stack size", "bytes"}, 533 [RLIMIT_CORE] = {"Max core file size", "bytes"}, 534 [RLIMIT_RSS] = {"Max resident set", "bytes"}, 535 [RLIMIT_NPROC] = {"Max processes", "processes"}, 536 [RLIMIT_NOFILE] = {"Max open files", "files"}, 537 [RLIMIT_MEMLOCK] = {"Max locked memory", "bytes"}, 538 [RLIMIT_AS] = {"Max address space", "bytes"}, 539 [RLIMIT_LOCKS] = {"Max file locks", "locks"}, 540 [RLIMIT_SIGPENDING] = {"Max pending signals", "signals"}, 541 [RLIMIT_MSGQUEUE] = {"Max msgqueue size", "bytes"}, 542 [RLIMIT_NICE] = {"Max nice priority", NULL}, 543 [RLIMIT_RTPRIO] = {"Max realtime priority", NULL}, 544 [RLIMIT_RTTIME] = {"Max realtime timeout", "us"}, 545 }; 546 547 /* Display limits for a process */ 548 static int proc_pid_limits(struct seq_file *m, struct pid_namespace *ns, 549 struct pid *pid, struct task_struct *task) 550 { 551 unsigned int i; 552 unsigned long flags; 553 554 struct rlimit rlim[RLIM_NLIMITS]; 555 556 if (!lock_task_sighand(task, &flags)) 557 return 0; 558 memcpy(rlim, task->signal->rlim, sizeof(struct rlimit) * RLIM_NLIMITS); 559 unlock_task_sighand(task, &flags); 560 561 /* 562 * print the file header 563 */ 564 seq_printf(m, "%-25s %-20s %-20s %-10s\n", 565 "Limit", "Soft Limit", "Hard Limit", "Units"); 566 567 for (i = 0; i < RLIM_NLIMITS; i++) { 568 if (rlim[i].rlim_cur == RLIM_INFINITY) 569 seq_printf(m, "%-25s %-20s ", 570 lnames[i].name, "unlimited"); 571 else 572 seq_printf(m, "%-25s %-20lu ", 573 lnames[i].name, rlim[i].rlim_cur); 574 575 if (rlim[i].rlim_max == RLIM_INFINITY) 576 seq_printf(m, "%-20s ", "unlimited"); 577 else 578 seq_printf(m, "%-20lu ", rlim[i].rlim_max); 579 580 if (lnames[i].unit) 581 seq_printf(m, "%-10s\n", lnames[i].unit); 582 else 583 seq_putc(m, '\n'); 584 } 585 586 return 0; 587 } 588 589 #ifdef CONFIG_HAVE_ARCH_TRACEHOOK 590 static int proc_pid_syscall(struct seq_file *m, struct pid_namespace *ns, 591 struct pid *pid, struct task_struct *task) 592 { 593 long nr; 594 unsigned long args[6], sp, pc; 595 int res; 596 597 res = lock_trace(task); 598 if (res) 599 return res; 600 601 if (task_current_syscall(task, &nr, args, 6, &sp, &pc)) 602 seq_puts(m, "running\n"); 603 else if (nr < 0) 604 seq_printf(m, "%ld 0x%lx 0x%lx\n", nr, sp, pc); 605 else 606 seq_printf(m, 607 "%ld 0x%lx 0x%lx 0x%lx 0x%lx 0x%lx 0x%lx 0x%lx 0x%lx\n", 608 nr, 609 args[0], args[1], args[2], args[3], args[4], args[5], 610 sp, pc); 611 unlock_trace(task); 612 613 return 0; 614 } 615 #endif /* CONFIG_HAVE_ARCH_TRACEHOOK */ 616 617 /************************************************************************/ 618 /* Here the fs part begins */ 619 /************************************************************************/ 620 621 /* permission checks */ 622 static int proc_fd_access_allowed(struct inode *inode) 623 { 624 struct task_struct *task; 625 int allowed = 0; 626 /* Allow access to a task's file descriptors if it is us or we 627 * may use ptrace attach to the process and find out that 628 * information. 629 */ 630 task = get_proc_task(inode); 631 if (task) { 632 allowed = ptrace_may_access(task, PTRACE_MODE_READ_FSCREDS); 633 put_task_struct(task); 634 } 635 return allowed; 636 } 637 638 int proc_setattr(struct dentry *dentry, struct iattr *attr) 639 { 640 int error; 641 struct inode *inode = d_inode(dentry); 642 643 if (attr->ia_valid & ATTR_MODE) 644 return -EPERM; 645 646 error = setattr_prepare(dentry, attr); 647 if (error) 648 return error; 649 650 setattr_copy(inode, attr); 651 mark_inode_dirty(inode); 652 return 0; 653 } 654 655 /* 656 * May current process learn task's sched/cmdline info (for hide_pid_min=1) 657 * or euid/egid (for hide_pid_min=2)? 658 */ 659 static bool has_pid_permissions(struct pid_namespace *pid, 660 struct task_struct *task, 661 int hide_pid_min) 662 { 663 if (pid->hide_pid < hide_pid_min) 664 return true; 665 if (in_group_p(pid->pid_gid)) 666 return true; 667 return ptrace_may_access(task, PTRACE_MODE_READ_FSCREDS); 668 } 669 670 671 static int proc_pid_permission(struct inode *inode, int mask) 672 { 673 struct pid_namespace *pid = proc_pid_ns(inode); 674 struct task_struct *task; 675 bool has_perms; 676 677 task = get_proc_task(inode); 678 if (!task) 679 return -ESRCH; 680 has_perms = has_pid_permissions(pid, task, HIDEPID_NO_ACCESS); 681 put_task_struct(task); 682 683 if (!has_perms) { 684 if (pid->hide_pid == HIDEPID_INVISIBLE) { 685 /* 686 * Let's make getdents(), stat(), and open() 687 * consistent with each other. If a process 688 * may not stat() a file, it shouldn't be seen 689 * in procfs at all. 690 */ 691 return -ENOENT; 692 } 693 694 return -EPERM; 695 } 696 return generic_permission(inode, mask); 697 } 698 699 700 701 static const struct inode_operations proc_def_inode_operations = { 702 .setattr = proc_setattr, 703 }; 704 705 static int proc_single_show(struct seq_file *m, void *v) 706 { 707 struct inode *inode = m->private; 708 struct pid_namespace *ns = proc_pid_ns(inode); 709 struct pid *pid = proc_pid(inode); 710 struct task_struct *task; 711 int ret; 712 713 task = get_pid_task(pid, PIDTYPE_PID); 714 if (!task) 715 return -ESRCH; 716 717 ret = PROC_I(inode)->op.proc_show(m, ns, pid, task); 718 719 put_task_struct(task); 720 return ret; 721 } 722 723 static int proc_single_open(struct inode *inode, struct file *filp) 724 { 725 return single_open(filp, proc_single_show, inode); 726 } 727 728 static const struct file_operations proc_single_file_operations = { 729 .open = proc_single_open, 730 .read = seq_read, 731 .llseek = seq_lseek, 732 .release = single_release, 733 }; 734 735 736 struct mm_struct *proc_mem_open(struct inode *inode, unsigned int mode) 737 { 738 struct task_struct *task = get_proc_task(inode); 739 struct mm_struct *mm = ERR_PTR(-ESRCH); 740 741 if (task) { 742 mm = mm_access(task, mode | PTRACE_MODE_FSCREDS); 743 put_task_struct(task); 744 745 if (!IS_ERR_OR_NULL(mm)) { 746 /* ensure this mm_struct can't be freed */ 747 mmgrab(mm); 748 /* but do not pin its memory */ 749 mmput(mm); 750 } 751 } 752 753 return mm; 754 } 755 756 static int __mem_open(struct inode *inode, struct file *file, unsigned int mode) 757 { 758 struct mm_struct *mm = proc_mem_open(inode, mode); 759 760 if (IS_ERR(mm)) 761 return PTR_ERR(mm); 762 763 file->private_data = mm; 764 return 0; 765 } 766 767 static int mem_open(struct inode *inode, struct file *file) 768 { 769 int ret = __mem_open(inode, file, PTRACE_MODE_ATTACH); 770 771 /* OK to pass negative loff_t, we can catch out-of-range */ 772 file->f_mode |= FMODE_UNSIGNED_OFFSET; 773 774 return ret; 775 } 776 777 static ssize_t mem_rw(struct file *file, char __user *buf, 778 size_t count, loff_t *ppos, int write) 779 { 780 struct mm_struct *mm = file->private_data; 781 unsigned long addr = *ppos; 782 ssize_t copied; 783 char *page; 784 unsigned int flags; 785 786 if (!mm) 787 return 0; 788 789 page = (char *)__get_free_page(GFP_KERNEL); 790 if (!page) 791 return -ENOMEM; 792 793 copied = 0; 794 if (!mmget_not_zero(mm)) 795 goto free; 796 797 flags = FOLL_FORCE | (write ? FOLL_WRITE : 0); 798 799 while (count > 0) { 800 int this_len = min_t(int, count, PAGE_SIZE); 801 802 if (write && copy_from_user(page, buf, this_len)) { 803 copied = -EFAULT; 804 break; 805 } 806 807 this_len = access_remote_vm(mm, addr, page, this_len, flags); 808 if (!this_len) { 809 if (!copied) 810 copied = -EIO; 811 break; 812 } 813 814 if (!write && copy_to_user(buf, page, this_len)) { 815 copied = -EFAULT; 816 break; 817 } 818 819 buf += this_len; 820 addr += this_len; 821 copied += this_len; 822 count -= this_len; 823 } 824 *ppos = addr; 825 826 mmput(mm); 827 free: 828 free_page((unsigned long) page); 829 return copied; 830 } 831 832 static ssize_t mem_read(struct file *file, char __user *buf, 833 size_t count, loff_t *ppos) 834 { 835 return mem_rw(file, buf, count, ppos, 0); 836 } 837 838 static ssize_t mem_write(struct file *file, const char __user *buf, 839 size_t count, loff_t *ppos) 840 { 841 return mem_rw(file, (char __user*)buf, count, ppos, 1); 842 } 843 844 loff_t mem_lseek(struct file *file, loff_t offset, int orig) 845 { 846 switch (orig) { 847 case 0: 848 file->f_pos = offset; 849 break; 850 case 1: 851 file->f_pos += offset; 852 break; 853 default: 854 return -EINVAL; 855 } 856 force_successful_syscall_return(); 857 return file->f_pos; 858 } 859 860 static int mem_release(struct inode *inode, struct file *file) 861 { 862 struct mm_struct *mm = file->private_data; 863 if (mm) 864 mmdrop(mm); 865 return 0; 866 } 867 868 static const struct file_operations proc_mem_operations = { 869 .llseek = mem_lseek, 870 .read = mem_read, 871 .write = mem_write, 872 .open = mem_open, 873 .release = mem_release, 874 }; 875 876 static int environ_open(struct inode *inode, struct file *file) 877 { 878 return __mem_open(inode, file, PTRACE_MODE_READ); 879 } 880 881 static ssize_t environ_read(struct file *file, char __user *buf, 882 size_t count, loff_t *ppos) 883 { 884 char *page; 885 unsigned long src = *ppos; 886 int ret = 0; 887 struct mm_struct *mm = file->private_data; 888 unsigned long env_start, env_end; 889 890 /* Ensure the process spawned far enough to have an environment. */ 891 if (!mm || !mm->env_end) 892 return 0; 893 894 page = (char *)__get_free_page(GFP_KERNEL); 895 if (!page) 896 return -ENOMEM; 897 898 ret = 0; 899 if (!mmget_not_zero(mm)) 900 goto free; 901 902 spin_lock(&mm->arg_lock); 903 env_start = mm->env_start; 904 env_end = mm->env_end; 905 spin_unlock(&mm->arg_lock); 906 907 while (count > 0) { 908 size_t this_len, max_len; 909 int retval; 910 911 if (src >= (env_end - env_start)) 912 break; 913 914 this_len = env_end - (env_start + src); 915 916 max_len = min_t(size_t, PAGE_SIZE, count); 917 this_len = min(max_len, this_len); 918 919 retval = access_remote_vm(mm, (env_start + src), page, this_len, FOLL_ANON); 920 921 if (retval <= 0) { 922 ret = retval; 923 break; 924 } 925 926 if (copy_to_user(buf, page, retval)) { 927 ret = -EFAULT; 928 break; 929 } 930 931 ret += retval; 932 src += retval; 933 buf += retval; 934 count -= retval; 935 } 936 *ppos = src; 937 mmput(mm); 938 939 free: 940 free_page((unsigned long) page); 941 return ret; 942 } 943 944 static const struct file_operations proc_environ_operations = { 945 .open = environ_open, 946 .read = environ_read, 947 .llseek = generic_file_llseek, 948 .release = mem_release, 949 }; 950 951 static int auxv_open(struct inode *inode, struct file *file) 952 { 953 return __mem_open(inode, file, PTRACE_MODE_READ_FSCREDS); 954 } 955 956 static ssize_t auxv_read(struct file *file, char __user *buf, 957 size_t count, loff_t *ppos) 958 { 959 struct mm_struct *mm = file->private_data; 960 unsigned int nwords = 0; 961 962 if (!mm) 963 return 0; 964 do { 965 nwords += 2; 966 } while (mm->saved_auxv[nwords - 2] != 0); /* AT_NULL */ 967 return simple_read_from_buffer(buf, count, ppos, mm->saved_auxv, 968 nwords * sizeof(mm->saved_auxv[0])); 969 } 970 971 static const struct file_operations proc_auxv_operations = { 972 .open = auxv_open, 973 .read = auxv_read, 974 .llseek = generic_file_llseek, 975 .release = mem_release, 976 }; 977 978 static ssize_t oom_adj_read(struct file *file, char __user *buf, size_t count, 979 loff_t *ppos) 980 { 981 struct task_struct *task = get_proc_task(file_inode(file)); 982 char buffer[PROC_NUMBUF]; 983 int oom_adj = OOM_ADJUST_MIN; 984 size_t len; 985 986 if (!task) 987 return -ESRCH; 988 if (task->signal->oom_score_adj == OOM_SCORE_ADJ_MAX) 989 oom_adj = OOM_ADJUST_MAX; 990 else 991 oom_adj = (task->signal->oom_score_adj * -OOM_DISABLE) / 992 OOM_SCORE_ADJ_MAX; 993 put_task_struct(task); 994 len = snprintf(buffer, sizeof(buffer), "%d\n", oom_adj); 995 return simple_read_from_buffer(buf, count, ppos, buffer, len); 996 } 997 998 static int __set_oom_adj(struct file *file, int oom_adj, bool legacy) 999 { 1000 static DEFINE_MUTEX(oom_adj_mutex); 1001 struct mm_struct *mm = NULL; 1002 struct task_struct *task; 1003 int err = 0; 1004 1005 task = get_proc_task(file_inode(file)); 1006 if (!task) 1007 return -ESRCH; 1008 1009 mutex_lock(&oom_adj_mutex); 1010 if (legacy) { 1011 if (oom_adj < task->signal->oom_score_adj && 1012 !capable(CAP_SYS_RESOURCE)) { 1013 err = -EACCES; 1014 goto err_unlock; 1015 } 1016 /* 1017 * /proc/pid/oom_adj is provided for legacy purposes, ask users to use 1018 * /proc/pid/oom_score_adj instead. 1019 */ 1020 pr_warn_once("%s (%d): /proc/%d/oom_adj is deprecated, please use /proc/%d/oom_score_adj instead.\n", 1021 current->comm, task_pid_nr(current), task_pid_nr(task), 1022 task_pid_nr(task)); 1023 } else { 1024 if ((short)oom_adj < task->signal->oom_score_adj_min && 1025 !capable(CAP_SYS_RESOURCE)) { 1026 err = -EACCES; 1027 goto err_unlock; 1028 } 1029 } 1030 1031 /* 1032 * Make sure we will check other processes sharing the mm if this is 1033 * not vfrok which wants its own oom_score_adj. 1034 * pin the mm so it doesn't go away and get reused after task_unlock 1035 */ 1036 if (!task->vfork_done) { 1037 struct task_struct *p = find_lock_task_mm(task); 1038 1039 if (p) { 1040 if (atomic_read(&p->mm->mm_users) > 1) { 1041 mm = p->mm; 1042 mmgrab(mm); 1043 } 1044 task_unlock(p); 1045 } 1046 } 1047 1048 task->signal->oom_score_adj = oom_adj; 1049 if (!legacy && has_capability_noaudit(current, CAP_SYS_RESOURCE)) 1050 task->signal->oom_score_adj_min = (short)oom_adj; 1051 trace_oom_score_adj_update(task); 1052 1053 if (mm) { 1054 struct task_struct *p; 1055 1056 rcu_read_lock(); 1057 for_each_process(p) { 1058 if (same_thread_group(task, p)) 1059 continue; 1060 1061 /* do not touch kernel threads or the global init */ 1062 if (p->flags & PF_KTHREAD || is_global_init(p)) 1063 continue; 1064 1065 task_lock(p); 1066 if (!p->vfork_done && process_shares_mm(p, mm)) { 1067 pr_info("updating oom_score_adj for %d (%s) from %d to %d because it shares mm with %d (%s). Report if this is unexpected.\n", 1068 task_pid_nr(p), p->comm, 1069 p->signal->oom_score_adj, oom_adj, 1070 task_pid_nr(task), task->comm); 1071 p->signal->oom_score_adj = oom_adj; 1072 if (!legacy && has_capability_noaudit(current, CAP_SYS_RESOURCE)) 1073 p->signal->oom_score_adj_min = (short)oom_adj; 1074 } 1075 task_unlock(p); 1076 } 1077 rcu_read_unlock(); 1078 mmdrop(mm); 1079 } 1080 err_unlock: 1081 mutex_unlock(&oom_adj_mutex); 1082 put_task_struct(task); 1083 return err; 1084 } 1085 1086 /* 1087 * /proc/pid/oom_adj exists solely for backwards compatibility with previous 1088 * kernels. The effective policy is defined by oom_score_adj, which has a 1089 * different scale: oom_adj grew exponentially and oom_score_adj grows linearly. 1090 * Values written to oom_adj are simply mapped linearly to oom_score_adj. 1091 * Processes that become oom disabled via oom_adj will still be oom disabled 1092 * with this implementation. 1093 * 1094 * oom_adj cannot be removed since existing userspace binaries use it. 1095 */ 1096 static ssize_t oom_adj_write(struct file *file, const char __user *buf, 1097 size_t count, loff_t *ppos) 1098 { 1099 char buffer[PROC_NUMBUF]; 1100 int oom_adj; 1101 int err; 1102 1103 memset(buffer, 0, sizeof(buffer)); 1104 if (count > sizeof(buffer) - 1) 1105 count = sizeof(buffer) - 1; 1106 if (copy_from_user(buffer, buf, count)) { 1107 err = -EFAULT; 1108 goto out; 1109 } 1110 1111 err = kstrtoint(strstrip(buffer), 0, &oom_adj); 1112 if (err) 1113 goto out; 1114 if ((oom_adj < OOM_ADJUST_MIN || oom_adj > OOM_ADJUST_MAX) && 1115 oom_adj != OOM_DISABLE) { 1116 err = -EINVAL; 1117 goto out; 1118 } 1119 1120 /* 1121 * Scale /proc/pid/oom_score_adj appropriately ensuring that a maximum 1122 * value is always attainable. 1123 */ 1124 if (oom_adj == OOM_ADJUST_MAX) 1125 oom_adj = OOM_SCORE_ADJ_MAX; 1126 else 1127 oom_adj = (oom_adj * OOM_SCORE_ADJ_MAX) / -OOM_DISABLE; 1128 1129 err = __set_oom_adj(file, oom_adj, true); 1130 out: 1131 return err < 0 ? err : count; 1132 } 1133 1134 static const struct file_operations proc_oom_adj_operations = { 1135 .read = oom_adj_read, 1136 .write = oom_adj_write, 1137 .llseek = generic_file_llseek, 1138 }; 1139 1140 static ssize_t oom_score_adj_read(struct file *file, char __user *buf, 1141 size_t count, loff_t *ppos) 1142 { 1143 struct task_struct *task = get_proc_task(file_inode(file)); 1144 char buffer[PROC_NUMBUF]; 1145 short oom_score_adj = OOM_SCORE_ADJ_MIN; 1146 size_t len; 1147 1148 if (!task) 1149 return -ESRCH; 1150 oom_score_adj = task->signal->oom_score_adj; 1151 put_task_struct(task); 1152 len = snprintf(buffer, sizeof(buffer), "%hd\n", oom_score_adj); 1153 return simple_read_from_buffer(buf, count, ppos, buffer, len); 1154 } 1155 1156 static ssize_t oom_score_adj_write(struct file *file, const char __user *buf, 1157 size_t count, loff_t *ppos) 1158 { 1159 char buffer[PROC_NUMBUF]; 1160 int oom_score_adj; 1161 int err; 1162 1163 memset(buffer, 0, sizeof(buffer)); 1164 if (count > sizeof(buffer) - 1) 1165 count = sizeof(buffer) - 1; 1166 if (copy_from_user(buffer, buf, count)) { 1167 err = -EFAULT; 1168 goto out; 1169 } 1170 1171 err = kstrtoint(strstrip(buffer), 0, &oom_score_adj); 1172 if (err) 1173 goto out; 1174 if (oom_score_adj < OOM_SCORE_ADJ_MIN || 1175 oom_score_adj > OOM_SCORE_ADJ_MAX) { 1176 err = -EINVAL; 1177 goto out; 1178 } 1179 1180 err = __set_oom_adj(file, oom_score_adj, false); 1181 out: 1182 return err < 0 ? err : count; 1183 } 1184 1185 static const struct file_operations proc_oom_score_adj_operations = { 1186 .read = oom_score_adj_read, 1187 .write = oom_score_adj_write, 1188 .llseek = default_llseek, 1189 }; 1190 1191 #ifdef CONFIG_AUDITSYSCALL 1192 #define TMPBUFLEN 11 1193 static ssize_t proc_loginuid_read(struct file * file, char __user * buf, 1194 size_t count, loff_t *ppos) 1195 { 1196 struct inode * inode = file_inode(file); 1197 struct task_struct *task = get_proc_task(inode); 1198 ssize_t length; 1199 char tmpbuf[TMPBUFLEN]; 1200 1201 if (!task) 1202 return -ESRCH; 1203 length = scnprintf(tmpbuf, TMPBUFLEN, "%u", 1204 from_kuid(file->f_cred->user_ns, 1205 audit_get_loginuid(task))); 1206 put_task_struct(task); 1207 return simple_read_from_buffer(buf, count, ppos, tmpbuf, length); 1208 } 1209 1210 static ssize_t proc_loginuid_write(struct file * file, const char __user * buf, 1211 size_t count, loff_t *ppos) 1212 { 1213 struct inode * inode = file_inode(file); 1214 uid_t loginuid; 1215 kuid_t kloginuid; 1216 int rv; 1217 1218 rcu_read_lock(); 1219 if (current != pid_task(proc_pid(inode), PIDTYPE_PID)) { 1220 rcu_read_unlock(); 1221 return -EPERM; 1222 } 1223 rcu_read_unlock(); 1224 1225 if (*ppos != 0) { 1226 /* No partial writes. */ 1227 return -EINVAL; 1228 } 1229 1230 rv = kstrtou32_from_user(buf, count, 10, &loginuid); 1231 if (rv < 0) 1232 return rv; 1233 1234 /* is userspace tring to explicitly UNSET the loginuid? */ 1235 if (loginuid == AUDIT_UID_UNSET) { 1236 kloginuid = INVALID_UID; 1237 } else { 1238 kloginuid = make_kuid(file->f_cred->user_ns, loginuid); 1239 if (!uid_valid(kloginuid)) 1240 return -EINVAL; 1241 } 1242 1243 rv = audit_set_loginuid(kloginuid); 1244 if (rv < 0) 1245 return rv; 1246 return count; 1247 } 1248 1249 static const struct file_operations proc_loginuid_operations = { 1250 .read = proc_loginuid_read, 1251 .write = proc_loginuid_write, 1252 .llseek = generic_file_llseek, 1253 }; 1254 1255 static ssize_t proc_sessionid_read(struct file * file, char __user * buf, 1256 size_t count, loff_t *ppos) 1257 { 1258 struct inode * inode = file_inode(file); 1259 struct task_struct *task = get_proc_task(inode); 1260 ssize_t length; 1261 char tmpbuf[TMPBUFLEN]; 1262 1263 if (!task) 1264 return -ESRCH; 1265 length = scnprintf(tmpbuf, TMPBUFLEN, "%u", 1266 audit_get_sessionid(task)); 1267 put_task_struct(task); 1268 return simple_read_from_buffer(buf, count, ppos, tmpbuf, length); 1269 } 1270 1271 static const struct file_operations proc_sessionid_operations = { 1272 .read = proc_sessionid_read, 1273 .llseek = generic_file_llseek, 1274 }; 1275 #endif 1276 1277 #ifdef CONFIG_FAULT_INJECTION 1278 static ssize_t proc_fault_inject_read(struct file * file, char __user * buf, 1279 size_t count, loff_t *ppos) 1280 { 1281 struct task_struct *task = get_proc_task(file_inode(file)); 1282 char buffer[PROC_NUMBUF]; 1283 size_t len; 1284 int make_it_fail; 1285 1286 if (!task) 1287 return -ESRCH; 1288 make_it_fail = task->make_it_fail; 1289 put_task_struct(task); 1290 1291 len = snprintf(buffer, sizeof(buffer), "%i\n", make_it_fail); 1292 1293 return simple_read_from_buffer(buf, count, ppos, buffer, len); 1294 } 1295 1296 static ssize_t proc_fault_inject_write(struct file * file, 1297 const char __user * buf, size_t count, loff_t *ppos) 1298 { 1299 struct task_struct *task; 1300 char buffer[PROC_NUMBUF]; 1301 int make_it_fail; 1302 int rv; 1303 1304 if (!capable(CAP_SYS_RESOURCE)) 1305 return -EPERM; 1306 memset(buffer, 0, sizeof(buffer)); 1307 if (count > sizeof(buffer) - 1) 1308 count = sizeof(buffer) - 1; 1309 if (copy_from_user(buffer, buf, count)) 1310 return -EFAULT; 1311 rv = kstrtoint(strstrip(buffer), 0, &make_it_fail); 1312 if (rv < 0) 1313 return rv; 1314 if (make_it_fail < 0 || make_it_fail > 1) 1315 return -EINVAL; 1316 1317 task = get_proc_task(file_inode(file)); 1318 if (!task) 1319 return -ESRCH; 1320 task->make_it_fail = make_it_fail; 1321 put_task_struct(task); 1322 1323 return count; 1324 } 1325 1326 static const struct file_operations proc_fault_inject_operations = { 1327 .read = proc_fault_inject_read, 1328 .write = proc_fault_inject_write, 1329 .llseek = generic_file_llseek, 1330 }; 1331 1332 static ssize_t proc_fail_nth_write(struct file *file, const char __user *buf, 1333 size_t count, loff_t *ppos) 1334 { 1335 struct task_struct *task; 1336 int err; 1337 unsigned int n; 1338 1339 err = kstrtouint_from_user(buf, count, 0, &n); 1340 if (err) 1341 return err; 1342 1343 task = get_proc_task(file_inode(file)); 1344 if (!task) 1345 return -ESRCH; 1346 task->fail_nth = n; 1347 put_task_struct(task); 1348 1349 return count; 1350 } 1351 1352 static ssize_t proc_fail_nth_read(struct file *file, char __user *buf, 1353 size_t count, loff_t *ppos) 1354 { 1355 struct task_struct *task; 1356 char numbuf[PROC_NUMBUF]; 1357 ssize_t len; 1358 1359 task = get_proc_task(file_inode(file)); 1360 if (!task) 1361 return -ESRCH; 1362 len = snprintf(numbuf, sizeof(numbuf), "%u\n", task->fail_nth); 1363 len = simple_read_from_buffer(buf, count, ppos, numbuf, len); 1364 put_task_struct(task); 1365 1366 return len; 1367 } 1368 1369 static const struct file_operations proc_fail_nth_operations = { 1370 .read = proc_fail_nth_read, 1371 .write = proc_fail_nth_write, 1372 }; 1373 #endif 1374 1375 1376 #ifdef CONFIG_SCHED_DEBUG 1377 /* 1378 * Print out various scheduling related per-task fields: 1379 */ 1380 static int sched_show(struct seq_file *m, void *v) 1381 { 1382 struct inode *inode = m->private; 1383 struct pid_namespace *ns = proc_pid_ns(inode); 1384 struct task_struct *p; 1385 1386 p = get_proc_task(inode); 1387 if (!p) 1388 return -ESRCH; 1389 proc_sched_show_task(p, ns, m); 1390 1391 put_task_struct(p); 1392 1393 return 0; 1394 } 1395 1396 static ssize_t 1397 sched_write(struct file *file, const char __user *buf, 1398 size_t count, loff_t *offset) 1399 { 1400 struct inode *inode = file_inode(file); 1401 struct task_struct *p; 1402 1403 p = get_proc_task(inode); 1404 if (!p) 1405 return -ESRCH; 1406 proc_sched_set_task(p); 1407 1408 put_task_struct(p); 1409 1410 return count; 1411 } 1412 1413 static int sched_open(struct inode *inode, struct file *filp) 1414 { 1415 return single_open(filp, sched_show, inode); 1416 } 1417 1418 static const struct file_operations proc_pid_sched_operations = { 1419 .open = sched_open, 1420 .read = seq_read, 1421 .write = sched_write, 1422 .llseek = seq_lseek, 1423 .release = single_release, 1424 }; 1425 1426 #endif 1427 1428 #ifdef CONFIG_SCHED_AUTOGROUP 1429 /* 1430 * Print out autogroup related information: 1431 */ 1432 static int sched_autogroup_show(struct seq_file *m, void *v) 1433 { 1434 struct inode *inode = m->private; 1435 struct task_struct *p; 1436 1437 p = get_proc_task(inode); 1438 if (!p) 1439 return -ESRCH; 1440 proc_sched_autogroup_show_task(p, m); 1441 1442 put_task_struct(p); 1443 1444 return 0; 1445 } 1446 1447 static ssize_t 1448 sched_autogroup_write(struct file *file, const char __user *buf, 1449 size_t count, loff_t *offset) 1450 { 1451 struct inode *inode = file_inode(file); 1452 struct task_struct *p; 1453 char buffer[PROC_NUMBUF]; 1454 int nice; 1455 int err; 1456 1457 memset(buffer, 0, sizeof(buffer)); 1458 if (count > sizeof(buffer) - 1) 1459 count = sizeof(buffer) - 1; 1460 if (copy_from_user(buffer, buf, count)) 1461 return -EFAULT; 1462 1463 err = kstrtoint(strstrip(buffer), 0, &nice); 1464 if (err < 0) 1465 return err; 1466 1467 p = get_proc_task(inode); 1468 if (!p) 1469 return -ESRCH; 1470 1471 err = proc_sched_autogroup_set_nice(p, nice); 1472 if (err) 1473 count = err; 1474 1475 put_task_struct(p); 1476 1477 return count; 1478 } 1479 1480 static int sched_autogroup_open(struct inode *inode, struct file *filp) 1481 { 1482 int ret; 1483 1484 ret = single_open(filp, sched_autogroup_show, NULL); 1485 if (!ret) { 1486 struct seq_file *m = filp->private_data; 1487 1488 m->private = inode; 1489 } 1490 return ret; 1491 } 1492 1493 static const struct file_operations proc_pid_sched_autogroup_operations = { 1494 .open = sched_autogroup_open, 1495 .read = seq_read, 1496 .write = sched_autogroup_write, 1497 .llseek = seq_lseek, 1498 .release = single_release, 1499 }; 1500 1501 #endif /* CONFIG_SCHED_AUTOGROUP */ 1502 1503 static ssize_t comm_write(struct file *file, const char __user *buf, 1504 size_t count, loff_t *offset) 1505 { 1506 struct inode *inode = file_inode(file); 1507 struct task_struct *p; 1508 char buffer[TASK_COMM_LEN]; 1509 const size_t maxlen = sizeof(buffer) - 1; 1510 1511 memset(buffer, 0, sizeof(buffer)); 1512 if (copy_from_user(buffer, buf, count > maxlen ? maxlen : count)) 1513 return -EFAULT; 1514 1515 p = get_proc_task(inode); 1516 if (!p) 1517 return -ESRCH; 1518 1519 if (same_thread_group(current, p)) 1520 set_task_comm(p, buffer); 1521 else 1522 count = -EINVAL; 1523 1524 put_task_struct(p); 1525 1526 return count; 1527 } 1528 1529 static int comm_show(struct seq_file *m, void *v) 1530 { 1531 struct inode *inode = m->private; 1532 struct task_struct *p; 1533 1534 p = get_proc_task(inode); 1535 if (!p) 1536 return -ESRCH; 1537 1538 proc_task_name(m, p, false); 1539 seq_putc(m, '\n'); 1540 1541 put_task_struct(p); 1542 1543 return 0; 1544 } 1545 1546 static int comm_open(struct inode *inode, struct file *filp) 1547 { 1548 return single_open(filp, comm_show, inode); 1549 } 1550 1551 static const struct file_operations proc_pid_set_comm_operations = { 1552 .open = comm_open, 1553 .read = seq_read, 1554 .write = comm_write, 1555 .llseek = seq_lseek, 1556 .release = single_release, 1557 }; 1558 1559 static int proc_exe_link(struct dentry *dentry, struct path *exe_path) 1560 { 1561 struct task_struct *task; 1562 struct file *exe_file; 1563 1564 task = get_proc_task(d_inode(dentry)); 1565 if (!task) 1566 return -ENOENT; 1567 exe_file = get_task_exe_file(task); 1568 put_task_struct(task); 1569 if (exe_file) { 1570 *exe_path = exe_file->f_path; 1571 path_get(&exe_file->f_path); 1572 fput(exe_file); 1573 return 0; 1574 } else 1575 return -ENOENT; 1576 } 1577 1578 static const char *proc_pid_get_link(struct dentry *dentry, 1579 struct inode *inode, 1580 struct delayed_call *done) 1581 { 1582 struct path path; 1583 int error = -EACCES; 1584 1585 if (!dentry) 1586 return ERR_PTR(-ECHILD); 1587 1588 /* Are we allowed to snoop on the tasks file descriptors? */ 1589 if (!proc_fd_access_allowed(inode)) 1590 goto out; 1591 1592 error = PROC_I(inode)->op.proc_get_link(dentry, &path); 1593 if (error) 1594 goto out; 1595 1596 nd_jump_link(&path); 1597 return NULL; 1598 out: 1599 return ERR_PTR(error); 1600 } 1601 1602 static int do_proc_readlink(struct path *path, char __user *buffer, int buflen) 1603 { 1604 char *tmp = (char *)__get_free_page(GFP_KERNEL); 1605 char *pathname; 1606 int len; 1607 1608 if (!tmp) 1609 return -ENOMEM; 1610 1611 pathname = d_path(path, tmp, PAGE_SIZE); 1612 len = PTR_ERR(pathname); 1613 if (IS_ERR(pathname)) 1614 goto out; 1615 len = tmp + PAGE_SIZE - 1 - pathname; 1616 1617 if (len > buflen) 1618 len = buflen; 1619 if (copy_to_user(buffer, pathname, len)) 1620 len = -EFAULT; 1621 out: 1622 free_page((unsigned long)tmp); 1623 return len; 1624 } 1625 1626 static int proc_pid_readlink(struct dentry * dentry, char __user * buffer, int buflen) 1627 { 1628 int error = -EACCES; 1629 struct inode *inode = d_inode(dentry); 1630 struct path path; 1631 1632 /* Are we allowed to snoop on the tasks file descriptors? */ 1633 if (!proc_fd_access_allowed(inode)) 1634 goto out; 1635 1636 error = PROC_I(inode)->op.proc_get_link(dentry, &path); 1637 if (error) 1638 goto out; 1639 1640 error = do_proc_readlink(&path, buffer, buflen); 1641 path_put(&path); 1642 out: 1643 return error; 1644 } 1645 1646 const struct inode_operations proc_pid_link_inode_operations = { 1647 .readlink = proc_pid_readlink, 1648 .get_link = proc_pid_get_link, 1649 .setattr = proc_setattr, 1650 }; 1651 1652 1653 /* building an inode */ 1654 1655 void task_dump_owner(struct task_struct *task, umode_t mode, 1656 kuid_t *ruid, kgid_t *rgid) 1657 { 1658 /* Depending on the state of dumpable compute who should own a 1659 * proc file for a task. 1660 */ 1661 const struct cred *cred; 1662 kuid_t uid; 1663 kgid_t gid; 1664 1665 if (unlikely(task->flags & PF_KTHREAD)) { 1666 *ruid = GLOBAL_ROOT_UID; 1667 *rgid = GLOBAL_ROOT_GID; 1668 return; 1669 } 1670 1671 /* Default to the tasks effective ownership */ 1672 rcu_read_lock(); 1673 cred = __task_cred(task); 1674 uid = cred->euid; 1675 gid = cred->egid; 1676 rcu_read_unlock(); 1677 1678 /* 1679 * Before the /proc/pid/status file was created the only way to read 1680 * the effective uid of a /process was to stat /proc/pid. Reading 1681 * /proc/pid/status is slow enough that procps and other packages 1682 * kept stating /proc/pid. To keep the rules in /proc simple I have 1683 * made this apply to all per process world readable and executable 1684 * directories. 1685 */ 1686 if (mode != (S_IFDIR|S_IRUGO|S_IXUGO)) { 1687 struct mm_struct *mm; 1688 task_lock(task); 1689 mm = task->mm; 1690 /* Make non-dumpable tasks owned by some root */ 1691 if (mm) { 1692 if (get_dumpable(mm) != SUID_DUMP_USER) { 1693 struct user_namespace *user_ns = mm->user_ns; 1694 1695 uid = make_kuid(user_ns, 0); 1696 if (!uid_valid(uid)) 1697 uid = GLOBAL_ROOT_UID; 1698 1699 gid = make_kgid(user_ns, 0); 1700 if (!gid_valid(gid)) 1701 gid = GLOBAL_ROOT_GID; 1702 } 1703 } else { 1704 uid = GLOBAL_ROOT_UID; 1705 gid = GLOBAL_ROOT_GID; 1706 } 1707 task_unlock(task); 1708 } 1709 *ruid = uid; 1710 *rgid = gid; 1711 } 1712 1713 struct inode *proc_pid_make_inode(struct super_block * sb, 1714 struct task_struct *task, umode_t mode) 1715 { 1716 struct inode * inode; 1717 struct proc_inode *ei; 1718 1719 /* We need a new inode */ 1720 1721 inode = new_inode(sb); 1722 if (!inode) 1723 goto out; 1724 1725 /* Common stuff */ 1726 ei = PROC_I(inode); 1727 inode->i_mode = mode; 1728 inode->i_ino = get_next_ino(); 1729 inode->i_mtime = inode->i_atime = inode->i_ctime = current_time(inode); 1730 inode->i_op = &proc_def_inode_operations; 1731 1732 /* 1733 * grab the reference to task. 1734 */ 1735 ei->pid = get_task_pid(task, PIDTYPE_PID); 1736 if (!ei->pid) 1737 goto out_unlock; 1738 1739 task_dump_owner(task, 0, &inode->i_uid, &inode->i_gid); 1740 security_task_to_inode(task, inode); 1741 1742 out: 1743 return inode; 1744 1745 out_unlock: 1746 iput(inode); 1747 return NULL; 1748 } 1749 1750 int pid_getattr(const struct path *path, struct kstat *stat, 1751 u32 request_mask, unsigned int query_flags) 1752 { 1753 struct inode *inode = d_inode(path->dentry); 1754 struct pid_namespace *pid = proc_pid_ns(inode); 1755 struct task_struct *task; 1756 1757 generic_fillattr(inode, stat); 1758 1759 stat->uid = GLOBAL_ROOT_UID; 1760 stat->gid = GLOBAL_ROOT_GID; 1761 rcu_read_lock(); 1762 task = pid_task(proc_pid(inode), PIDTYPE_PID); 1763 if (task) { 1764 if (!has_pid_permissions(pid, task, HIDEPID_INVISIBLE)) { 1765 rcu_read_unlock(); 1766 /* 1767 * This doesn't prevent learning whether PID exists, 1768 * it only makes getattr() consistent with readdir(). 1769 */ 1770 return -ENOENT; 1771 } 1772 task_dump_owner(task, inode->i_mode, &stat->uid, &stat->gid); 1773 } 1774 rcu_read_unlock(); 1775 return 0; 1776 } 1777 1778 /* dentry stuff */ 1779 1780 /* 1781 * Set <pid>/... inode ownership (can change due to setuid(), etc.) 1782 */ 1783 void pid_update_inode(struct task_struct *task, struct inode *inode) 1784 { 1785 task_dump_owner(task, inode->i_mode, &inode->i_uid, &inode->i_gid); 1786 1787 inode->i_mode &= ~(S_ISUID | S_ISGID); 1788 security_task_to_inode(task, inode); 1789 } 1790 1791 /* 1792 * Rewrite the inode's ownerships here because the owning task may have 1793 * performed a setuid(), etc. 1794 * 1795 */ 1796 static int pid_revalidate(struct dentry *dentry, unsigned int flags) 1797 { 1798 struct inode *inode; 1799 struct task_struct *task; 1800 1801 if (flags & LOOKUP_RCU) 1802 return -ECHILD; 1803 1804 inode = d_inode(dentry); 1805 task = get_proc_task(inode); 1806 1807 if (task) { 1808 pid_update_inode(task, inode); 1809 put_task_struct(task); 1810 return 1; 1811 } 1812 return 0; 1813 } 1814 1815 static inline bool proc_inode_is_dead(struct inode *inode) 1816 { 1817 return !proc_pid(inode)->tasks[PIDTYPE_PID].first; 1818 } 1819 1820 int pid_delete_dentry(const struct dentry *dentry) 1821 { 1822 /* Is the task we represent dead? 1823 * If so, then don't put the dentry on the lru list, 1824 * kill it immediately. 1825 */ 1826 return proc_inode_is_dead(d_inode(dentry)); 1827 } 1828 1829 const struct dentry_operations pid_dentry_operations = 1830 { 1831 .d_revalidate = pid_revalidate, 1832 .d_delete = pid_delete_dentry, 1833 }; 1834 1835 /* Lookups */ 1836 1837 /* 1838 * Fill a directory entry. 1839 * 1840 * If possible create the dcache entry and derive our inode number and 1841 * file type from dcache entry. 1842 * 1843 * Since all of the proc inode numbers are dynamically generated, the inode 1844 * numbers do not exist until the inode is cache. This means creating the 1845 * the dcache entry in readdir is necessary to keep the inode numbers 1846 * reported by readdir in sync with the inode numbers reported 1847 * by stat. 1848 */ 1849 bool proc_fill_cache(struct file *file, struct dir_context *ctx, 1850 const char *name, unsigned int len, 1851 instantiate_t instantiate, struct task_struct *task, const void *ptr) 1852 { 1853 struct dentry *child, *dir = file->f_path.dentry; 1854 struct qstr qname = QSTR_INIT(name, len); 1855 struct inode *inode; 1856 unsigned type = DT_UNKNOWN; 1857 ino_t ino = 1; 1858 1859 child = d_hash_and_lookup(dir, &qname); 1860 if (!child) { 1861 DECLARE_WAIT_QUEUE_HEAD_ONSTACK(wq); 1862 child = d_alloc_parallel(dir, &qname, &wq); 1863 if (IS_ERR(child)) 1864 goto end_instantiate; 1865 if (d_in_lookup(child)) { 1866 struct dentry *res; 1867 res = instantiate(child, task, ptr); 1868 d_lookup_done(child); 1869 if (unlikely(res)) { 1870 dput(child); 1871 child = res; 1872 if (IS_ERR(child)) 1873 goto end_instantiate; 1874 } 1875 } 1876 } 1877 inode = d_inode(child); 1878 ino = inode->i_ino; 1879 type = inode->i_mode >> 12; 1880 dput(child); 1881 end_instantiate: 1882 return dir_emit(ctx, name, len, ino, type); 1883 } 1884 1885 /* 1886 * dname_to_vma_addr - maps a dentry name into two unsigned longs 1887 * which represent vma start and end addresses. 1888 */ 1889 static int dname_to_vma_addr(struct dentry *dentry, 1890 unsigned long *start, unsigned long *end) 1891 { 1892 const char *str = dentry->d_name.name; 1893 unsigned long long sval, eval; 1894 unsigned int len; 1895 1896 if (str[0] == '0' && str[1] != '-') 1897 return -EINVAL; 1898 len = _parse_integer(str, 16, &sval); 1899 if (len & KSTRTOX_OVERFLOW) 1900 return -EINVAL; 1901 if (sval != (unsigned long)sval) 1902 return -EINVAL; 1903 str += len; 1904 1905 if (*str != '-') 1906 return -EINVAL; 1907 str++; 1908 1909 if (str[0] == '0' && str[1]) 1910 return -EINVAL; 1911 len = _parse_integer(str, 16, &eval); 1912 if (len & KSTRTOX_OVERFLOW) 1913 return -EINVAL; 1914 if (eval != (unsigned long)eval) 1915 return -EINVAL; 1916 str += len; 1917 1918 if (*str != '\0') 1919 return -EINVAL; 1920 1921 *start = sval; 1922 *end = eval; 1923 1924 return 0; 1925 } 1926 1927 static int map_files_d_revalidate(struct dentry *dentry, unsigned int flags) 1928 { 1929 unsigned long vm_start, vm_end; 1930 bool exact_vma_exists = false; 1931 struct mm_struct *mm = NULL; 1932 struct task_struct *task; 1933 struct inode *inode; 1934 int status = 0; 1935 1936 if (flags & LOOKUP_RCU) 1937 return -ECHILD; 1938 1939 inode = d_inode(dentry); 1940 task = get_proc_task(inode); 1941 if (!task) 1942 goto out_notask; 1943 1944 mm = mm_access(task, PTRACE_MODE_READ_FSCREDS); 1945 if (IS_ERR_OR_NULL(mm)) 1946 goto out; 1947 1948 if (!dname_to_vma_addr(dentry, &vm_start, &vm_end)) { 1949 down_read(&mm->mmap_sem); 1950 exact_vma_exists = !!find_exact_vma(mm, vm_start, vm_end); 1951 up_read(&mm->mmap_sem); 1952 } 1953 1954 mmput(mm); 1955 1956 if (exact_vma_exists) { 1957 task_dump_owner(task, 0, &inode->i_uid, &inode->i_gid); 1958 1959 security_task_to_inode(task, inode); 1960 status = 1; 1961 } 1962 1963 out: 1964 put_task_struct(task); 1965 1966 out_notask: 1967 return status; 1968 } 1969 1970 static const struct dentry_operations tid_map_files_dentry_operations = { 1971 .d_revalidate = map_files_d_revalidate, 1972 .d_delete = pid_delete_dentry, 1973 }; 1974 1975 static int map_files_get_link(struct dentry *dentry, struct path *path) 1976 { 1977 unsigned long vm_start, vm_end; 1978 struct vm_area_struct *vma; 1979 struct task_struct *task; 1980 struct mm_struct *mm; 1981 int rc; 1982 1983 rc = -ENOENT; 1984 task = get_proc_task(d_inode(dentry)); 1985 if (!task) 1986 goto out; 1987 1988 mm = get_task_mm(task); 1989 put_task_struct(task); 1990 if (!mm) 1991 goto out; 1992 1993 rc = dname_to_vma_addr(dentry, &vm_start, &vm_end); 1994 if (rc) 1995 goto out_mmput; 1996 1997 rc = -ENOENT; 1998 down_read(&mm->mmap_sem); 1999 vma = find_exact_vma(mm, vm_start, vm_end); 2000 if (vma && vma->vm_file) { 2001 *path = vma->vm_file->f_path; 2002 path_get(path); 2003 rc = 0; 2004 } 2005 up_read(&mm->mmap_sem); 2006 2007 out_mmput: 2008 mmput(mm); 2009 out: 2010 return rc; 2011 } 2012 2013 struct map_files_info { 2014 unsigned long start; 2015 unsigned long end; 2016 fmode_t mode; 2017 }; 2018 2019 /* 2020 * Only allow CAP_SYS_ADMIN to follow the links, due to concerns about how the 2021 * symlinks may be used to bypass permissions on ancestor directories in the 2022 * path to the file in question. 2023 */ 2024 static const char * 2025 proc_map_files_get_link(struct dentry *dentry, 2026 struct inode *inode, 2027 struct delayed_call *done) 2028 { 2029 if (!capable(CAP_SYS_ADMIN)) 2030 return ERR_PTR(-EPERM); 2031 2032 return proc_pid_get_link(dentry, inode, done); 2033 } 2034 2035 /* 2036 * Identical to proc_pid_link_inode_operations except for get_link() 2037 */ 2038 static const struct inode_operations proc_map_files_link_inode_operations = { 2039 .readlink = proc_pid_readlink, 2040 .get_link = proc_map_files_get_link, 2041 .setattr = proc_setattr, 2042 }; 2043 2044 static struct dentry * 2045 proc_map_files_instantiate(struct dentry *dentry, 2046 struct task_struct *task, const void *ptr) 2047 { 2048 fmode_t mode = (fmode_t)(unsigned long)ptr; 2049 struct proc_inode *ei; 2050 struct inode *inode; 2051 2052 inode = proc_pid_make_inode(dentry->d_sb, task, S_IFLNK | 2053 ((mode & FMODE_READ ) ? S_IRUSR : 0) | 2054 ((mode & FMODE_WRITE) ? S_IWUSR : 0)); 2055 if (!inode) 2056 return ERR_PTR(-ENOENT); 2057 2058 ei = PROC_I(inode); 2059 ei->op.proc_get_link = map_files_get_link; 2060 2061 inode->i_op = &proc_map_files_link_inode_operations; 2062 inode->i_size = 64; 2063 2064 d_set_d_op(dentry, &tid_map_files_dentry_operations); 2065 return d_splice_alias(inode, dentry); 2066 } 2067 2068 static struct dentry *proc_map_files_lookup(struct inode *dir, 2069 struct dentry *dentry, unsigned int flags) 2070 { 2071 unsigned long vm_start, vm_end; 2072 struct vm_area_struct *vma; 2073 struct task_struct *task; 2074 struct dentry *result; 2075 struct mm_struct *mm; 2076 2077 result = ERR_PTR(-ENOENT); 2078 task = get_proc_task(dir); 2079 if (!task) 2080 goto out; 2081 2082 result = ERR_PTR(-EACCES); 2083 if (!ptrace_may_access(task, PTRACE_MODE_READ_FSCREDS)) 2084 goto out_put_task; 2085 2086 result = ERR_PTR(-ENOENT); 2087 if (dname_to_vma_addr(dentry, &vm_start, &vm_end)) 2088 goto out_put_task; 2089 2090 mm = get_task_mm(task); 2091 if (!mm) 2092 goto out_put_task; 2093 2094 down_read(&mm->mmap_sem); 2095 vma = find_exact_vma(mm, vm_start, vm_end); 2096 if (!vma) 2097 goto out_no_vma; 2098 2099 if (vma->vm_file) 2100 result = proc_map_files_instantiate(dentry, task, 2101 (void *)(unsigned long)vma->vm_file->f_mode); 2102 2103 out_no_vma: 2104 up_read(&mm->mmap_sem); 2105 mmput(mm); 2106 out_put_task: 2107 put_task_struct(task); 2108 out: 2109 return result; 2110 } 2111 2112 static const struct inode_operations proc_map_files_inode_operations = { 2113 .lookup = proc_map_files_lookup, 2114 .permission = proc_fd_permission, 2115 .setattr = proc_setattr, 2116 }; 2117 2118 static int 2119 proc_map_files_readdir(struct file *file, struct dir_context *ctx) 2120 { 2121 struct vm_area_struct *vma; 2122 struct task_struct *task; 2123 struct mm_struct *mm; 2124 unsigned long nr_files, pos, i; 2125 struct flex_array *fa = NULL; 2126 struct map_files_info info; 2127 struct map_files_info *p; 2128 int ret; 2129 2130 ret = -ENOENT; 2131 task = get_proc_task(file_inode(file)); 2132 if (!task) 2133 goto out; 2134 2135 ret = -EACCES; 2136 if (!ptrace_may_access(task, PTRACE_MODE_READ_FSCREDS)) 2137 goto out_put_task; 2138 2139 ret = 0; 2140 if (!dir_emit_dots(file, ctx)) 2141 goto out_put_task; 2142 2143 mm = get_task_mm(task); 2144 if (!mm) 2145 goto out_put_task; 2146 down_read(&mm->mmap_sem); 2147 2148 nr_files = 0; 2149 2150 /* 2151 * We need two passes here: 2152 * 2153 * 1) Collect vmas of mapped files with mmap_sem taken 2154 * 2) Release mmap_sem and instantiate entries 2155 * 2156 * otherwise we get lockdep complained, since filldir() 2157 * routine might require mmap_sem taken in might_fault(). 2158 */ 2159 2160 for (vma = mm->mmap, pos = 2; vma; vma = vma->vm_next) { 2161 if (vma->vm_file && ++pos > ctx->pos) 2162 nr_files++; 2163 } 2164 2165 if (nr_files) { 2166 fa = flex_array_alloc(sizeof(info), nr_files, 2167 GFP_KERNEL); 2168 if (!fa || flex_array_prealloc(fa, 0, nr_files, 2169 GFP_KERNEL)) { 2170 ret = -ENOMEM; 2171 if (fa) 2172 flex_array_free(fa); 2173 up_read(&mm->mmap_sem); 2174 mmput(mm); 2175 goto out_put_task; 2176 } 2177 for (i = 0, vma = mm->mmap, pos = 2; vma; 2178 vma = vma->vm_next) { 2179 if (!vma->vm_file) 2180 continue; 2181 if (++pos <= ctx->pos) 2182 continue; 2183 2184 info.start = vma->vm_start; 2185 info.end = vma->vm_end; 2186 info.mode = vma->vm_file->f_mode; 2187 if (flex_array_put(fa, i++, &info, GFP_KERNEL)) 2188 BUG(); 2189 } 2190 } 2191 up_read(&mm->mmap_sem); 2192 mmput(mm); 2193 2194 for (i = 0; i < nr_files; i++) { 2195 char buf[4 * sizeof(long) + 2]; /* max: %lx-%lx\0 */ 2196 unsigned int len; 2197 2198 p = flex_array_get(fa, i); 2199 len = snprintf(buf, sizeof(buf), "%lx-%lx", p->start, p->end); 2200 if (!proc_fill_cache(file, ctx, 2201 buf, len, 2202 proc_map_files_instantiate, 2203 task, 2204 (void *)(unsigned long)p->mode)) 2205 break; 2206 ctx->pos++; 2207 } 2208 if (fa) 2209 flex_array_free(fa); 2210 2211 out_put_task: 2212 put_task_struct(task); 2213 out: 2214 return ret; 2215 } 2216 2217 static const struct file_operations proc_map_files_operations = { 2218 .read = generic_read_dir, 2219 .iterate_shared = proc_map_files_readdir, 2220 .llseek = generic_file_llseek, 2221 }; 2222 2223 #if defined(CONFIG_CHECKPOINT_RESTORE) && defined(CONFIG_POSIX_TIMERS) 2224 struct timers_private { 2225 struct pid *pid; 2226 struct task_struct *task; 2227 struct sighand_struct *sighand; 2228 struct pid_namespace *ns; 2229 unsigned long flags; 2230 }; 2231 2232 static void *timers_start(struct seq_file *m, loff_t *pos) 2233 { 2234 struct timers_private *tp = m->private; 2235 2236 tp->task = get_pid_task(tp->pid, PIDTYPE_PID); 2237 if (!tp->task) 2238 return ERR_PTR(-ESRCH); 2239 2240 tp->sighand = lock_task_sighand(tp->task, &tp->flags); 2241 if (!tp->sighand) 2242 return ERR_PTR(-ESRCH); 2243 2244 return seq_list_start(&tp->task->signal->posix_timers, *pos); 2245 } 2246 2247 static void *timers_next(struct seq_file *m, void *v, loff_t *pos) 2248 { 2249 struct timers_private *tp = m->private; 2250 return seq_list_next(v, &tp->task->signal->posix_timers, pos); 2251 } 2252 2253 static void timers_stop(struct seq_file *m, void *v) 2254 { 2255 struct timers_private *tp = m->private; 2256 2257 if (tp->sighand) { 2258 unlock_task_sighand(tp->task, &tp->flags); 2259 tp->sighand = NULL; 2260 } 2261 2262 if (tp->task) { 2263 put_task_struct(tp->task); 2264 tp->task = NULL; 2265 } 2266 } 2267 2268 static int show_timer(struct seq_file *m, void *v) 2269 { 2270 struct k_itimer *timer; 2271 struct timers_private *tp = m->private; 2272 int notify; 2273 static const char * const nstr[] = { 2274 [SIGEV_SIGNAL] = "signal", 2275 [SIGEV_NONE] = "none", 2276 [SIGEV_THREAD] = "thread", 2277 }; 2278 2279 timer = list_entry((struct list_head *)v, struct k_itimer, list); 2280 notify = timer->it_sigev_notify; 2281 2282 seq_printf(m, "ID: %d\n", timer->it_id); 2283 seq_printf(m, "signal: %d/%px\n", 2284 timer->sigq->info.si_signo, 2285 timer->sigq->info.si_value.sival_ptr); 2286 seq_printf(m, "notify: %s/%s.%d\n", 2287 nstr[notify & ~SIGEV_THREAD_ID], 2288 (notify & SIGEV_THREAD_ID) ? "tid" : "pid", 2289 pid_nr_ns(timer->it_pid, tp->ns)); 2290 seq_printf(m, "ClockID: %d\n", timer->it_clock); 2291 2292 return 0; 2293 } 2294 2295 static const struct seq_operations proc_timers_seq_ops = { 2296 .start = timers_start, 2297 .next = timers_next, 2298 .stop = timers_stop, 2299 .show = show_timer, 2300 }; 2301 2302 static int proc_timers_open(struct inode *inode, struct file *file) 2303 { 2304 struct timers_private *tp; 2305 2306 tp = __seq_open_private(file, &proc_timers_seq_ops, 2307 sizeof(struct timers_private)); 2308 if (!tp) 2309 return -ENOMEM; 2310 2311 tp->pid = proc_pid(inode); 2312 tp->ns = proc_pid_ns(inode); 2313 return 0; 2314 } 2315 2316 static const struct file_operations proc_timers_operations = { 2317 .open = proc_timers_open, 2318 .read = seq_read, 2319 .llseek = seq_lseek, 2320 .release = seq_release_private, 2321 }; 2322 #endif 2323 2324 static ssize_t timerslack_ns_write(struct file *file, const char __user *buf, 2325 size_t count, loff_t *offset) 2326 { 2327 struct inode *inode = file_inode(file); 2328 struct task_struct *p; 2329 u64 slack_ns; 2330 int err; 2331 2332 err = kstrtoull_from_user(buf, count, 10, &slack_ns); 2333 if (err < 0) 2334 return err; 2335 2336 p = get_proc_task(inode); 2337 if (!p) 2338 return -ESRCH; 2339 2340 if (p != current) { 2341 if (!capable(CAP_SYS_NICE)) { 2342 count = -EPERM; 2343 goto out; 2344 } 2345 2346 err = security_task_setscheduler(p); 2347 if (err) { 2348 count = err; 2349 goto out; 2350 } 2351 } 2352 2353 task_lock(p); 2354 if (slack_ns == 0) 2355 p->timer_slack_ns = p->default_timer_slack_ns; 2356 else 2357 p->timer_slack_ns = slack_ns; 2358 task_unlock(p); 2359 2360 out: 2361 put_task_struct(p); 2362 2363 return count; 2364 } 2365 2366 static int timerslack_ns_show(struct seq_file *m, void *v) 2367 { 2368 struct inode *inode = m->private; 2369 struct task_struct *p; 2370 int err = 0; 2371 2372 p = get_proc_task(inode); 2373 if (!p) 2374 return -ESRCH; 2375 2376 if (p != current) { 2377 2378 if (!capable(CAP_SYS_NICE)) { 2379 err = -EPERM; 2380 goto out; 2381 } 2382 err = security_task_getscheduler(p); 2383 if (err) 2384 goto out; 2385 } 2386 2387 task_lock(p); 2388 seq_printf(m, "%llu\n", p->timer_slack_ns); 2389 task_unlock(p); 2390 2391 out: 2392 put_task_struct(p); 2393 2394 return err; 2395 } 2396 2397 static int timerslack_ns_open(struct inode *inode, struct file *filp) 2398 { 2399 return single_open(filp, timerslack_ns_show, inode); 2400 } 2401 2402 static const struct file_operations proc_pid_set_timerslack_ns_operations = { 2403 .open = timerslack_ns_open, 2404 .read = seq_read, 2405 .write = timerslack_ns_write, 2406 .llseek = seq_lseek, 2407 .release = single_release, 2408 }; 2409 2410 static struct dentry *proc_pident_instantiate(struct dentry *dentry, 2411 struct task_struct *task, const void *ptr) 2412 { 2413 const struct pid_entry *p = ptr; 2414 struct inode *inode; 2415 struct proc_inode *ei; 2416 2417 inode = proc_pid_make_inode(dentry->d_sb, task, p->mode); 2418 if (!inode) 2419 return ERR_PTR(-ENOENT); 2420 2421 ei = PROC_I(inode); 2422 if (S_ISDIR(inode->i_mode)) 2423 set_nlink(inode, 2); /* Use getattr to fix if necessary */ 2424 if (p->iop) 2425 inode->i_op = p->iop; 2426 if (p->fop) 2427 inode->i_fop = p->fop; 2428 ei->op = p->op; 2429 pid_update_inode(task, inode); 2430 d_set_d_op(dentry, &pid_dentry_operations); 2431 return d_splice_alias(inode, dentry); 2432 } 2433 2434 static struct dentry *proc_pident_lookup(struct inode *dir, 2435 struct dentry *dentry, 2436 const struct pid_entry *ents, 2437 unsigned int nents) 2438 { 2439 struct task_struct *task = get_proc_task(dir); 2440 const struct pid_entry *p, *last; 2441 struct dentry *res = ERR_PTR(-ENOENT); 2442 2443 if (!task) 2444 goto out_no_task; 2445 2446 /* 2447 * Yes, it does not scale. And it should not. Don't add 2448 * new entries into /proc/<tgid>/ without very good reasons. 2449 */ 2450 last = &ents[nents]; 2451 for (p = ents; p < last; p++) { 2452 if (p->len != dentry->d_name.len) 2453 continue; 2454 if (!memcmp(dentry->d_name.name, p->name, p->len)) 2455 break; 2456 } 2457 if (p >= last) 2458 goto out; 2459 2460 res = proc_pident_instantiate(dentry, task, p); 2461 out: 2462 put_task_struct(task); 2463 out_no_task: 2464 return res; 2465 } 2466 2467 static int proc_pident_readdir(struct file *file, struct dir_context *ctx, 2468 const struct pid_entry *ents, unsigned int nents) 2469 { 2470 struct task_struct *task = get_proc_task(file_inode(file)); 2471 const struct pid_entry *p; 2472 2473 if (!task) 2474 return -ENOENT; 2475 2476 if (!dir_emit_dots(file, ctx)) 2477 goto out; 2478 2479 if (ctx->pos >= nents + 2) 2480 goto out; 2481 2482 for (p = ents + (ctx->pos - 2); p < ents + nents; p++) { 2483 if (!proc_fill_cache(file, ctx, p->name, p->len, 2484 proc_pident_instantiate, task, p)) 2485 break; 2486 ctx->pos++; 2487 } 2488 out: 2489 put_task_struct(task); 2490 return 0; 2491 } 2492 2493 #ifdef CONFIG_SECURITY 2494 static ssize_t proc_pid_attr_read(struct file * file, char __user * buf, 2495 size_t count, loff_t *ppos) 2496 { 2497 struct inode * inode = file_inode(file); 2498 char *p = NULL; 2499 ssize_t length; 2500 struct task_struct *task = get_proc_task(inode); 2501 2502 if (!task) 2503 return -ESRCH; 2504 2505 length = security_getprocattr(task, 2506 (char*)file->f_path.dentry->d_name.name, 2507 &p); 2508 put_task_struct(task); 2509 if (length > 0) 2510 length = simple_read_from_buffer(buf, count, ppos, p, length); 2511 kfree(p); 2512 return length; 2513 } 2514 2515 static ssize_t proc_pid_attr_write(struct file * file, const char __user * buf, 2516 size_t count, loff_t *ppos) 2517 { 2518 struct inode * inode = file_inode(file); 2519 void *page; 2520 ssize_t length; 2521 struct task_struct *task = get_proc_task(inode); 2522 2523 length = -ESRCH; 2524 if (!task) 2525 goto out_no_task; 2526 2527 /* A task may only write its own attributes. */ 2528 length = -EACCES; 2529 if (current != task) 2530 goto out; 2531 2532 if (count > PAGE_SIZE) 2533 count = PAGE_SIZE; 2534 2535 /* No partial writes. */ 2536 length = -EINVAL; 2537 if (*ppos != 0) 2538 goto out; 2539 2540 page = memdup_user(buf, count); 2541 if (IS_ERR(page)) { 2542 length = PTR_ERR(page); 2543 goto out; 2544 } 2545 2546 /* Guard against adverse ptrace interaction */ 2547 length = mutex_lock_interruptible(¤t->signal->cred_guard_mutex); 2548 if (length < 0) 2549 goto out_free; 2550 2551 length = security_setprocattr(file->f_path.dentry->d_name.name, 2552 page, count); 2553 mutex_unlock(¤t->signal->cred_guard_mutex); 2554 out_free: 2555 kfree(page); 2556 out: 2557 put_task_struct(task); 2558 out_no_task: 2559 return length; 2560 } 2561 2562 static const struct file_operations proc_pid_attr_operations = { 2563 .read = proc_pid_attr_read, 2564 .write = proc_pid_attr_write, 2565 .llseek = generic_file_llseek, 2566 }; 2567 2568 static const struct pid_entry attr_dir_stuff[] = { 2569 REG("current", S_IRUGO|S_IWUGO, proc_pid_attr_operations), 2570 REG("prev", S_IRUGO, proc_pid_attr_operations), 2571 REG("exec", S_IRUGO|S_IWUGO, proc_pid_attr_operations), 2572 REG("fscreate", S_IRUGO|S_IWUGO, proc_pid_attr_operations), 2573 REG("keycreate", S_IRUGO|S_IWUGO, proc_pid_attr_operations), 2574 REG("sockcreate", S_IRUGO|S_IWUGO, proc_pid_attr_operations), 2575 }; 2576 2577 static int proc_attr_dir_readdir(struct file *file, struct dir_context *ctx) 2578 { 2579 return proc_pident_readdir(file, ctx, 2580 attr_dir_stuff, ARRAY_SIZE(attr_dir_stuff)); 2581 } 2582 2583 static const struct file_operations proc_attr_dir_operations = { 2584 .read = generic_read_dir, 2585 .iterate_shared = proc_attr_dir_readdir, 2586 .llseek = generic_file_llseek, 2587 }; 2588 2589 static struct dentry *proc_attr_dir_lookup(struct inode *dir, 2590 struct dentry *dentry, unsigned int flags) 2591 { 2592 return proc_pident_lookup(dir, dentry, 2593 attr_dir_stuff, ARRAY_SIZE(attr_dir_stuff)); 2594 } 2595 2596 static const struct inode_operations proc_attr_dir_inode_operations = { 2597 .lookup = proc_attr_dir_lookup, 2598 .getattr = pid_getattr, 2599 .setattr = proc_setattr, 2600 }; 2601 2602 #endif 2603 2604 #ifdef CONFIG_ELF_CORE 2605 static ssize_t proc_coredump_filter_read(struct file *file, char __user *buf, 2606 size_t count, loff_t *ppos) 2607 { 2608 struct task_struct *task = get_proc_task(file_inode(file)); 2609 struct mm_struct *mm; 2610 char buffer[PROC_NUMBUF]; 2611 size_t len; 2612 int ret; 2613 2614 if (!task) 2615 return -ESRCH; 2616 2617 ret = 0; 2618 mm = get_task_mm(task); 2619 if (mm) { 2620 len = snprintf(buffer, sizeof(buffer), "%08lx\n", 2621 ((mm->flags & MMF_DUMP_FILTER_MASK) >> 2622 MMF_DUMP_FILTER_SHIFT)); 2623 mmput(mm); 2624 ret = simple_read_from_buffer(buf, count, ppos, buffer, len); 2625 } 2626 2627 put_task_struct(task); 2628 2629 return ret; 2630 } 2631 2632 static ssize_t proc_coredump_filter_write(struct file *file, 2633 const char __user *buf, 2634 size_t count, 2635 loff_t *ppos) 2636 { 2637 struct task_struct *task; 2638 struct mm_struct *mm; 2639 unsigned int val; 2640 int ret; 2641 int i; 2642 unsigned long mask; 2643 2644 ret = kstrtouint_from_user(buf, count, 0, &val); 2645 if (ret < 0) 2646 return ret; 2647 2648 ret = -ESRCH; 2649 task = get_proc_task(file_inode(file)); 2650 if (!task) 2651 goto out_no_task; 2652 2653 mm = get_task_mm(task); 2654 if (!mm) 2655 goto out_no_mm; 2656 ret = 0; 2657 2658 for (i = 0, mask = 1; i < MMF_DUMP_FILTER_BITS; i++, mask <<= 1) { 2659 if (val & mask) 2660 set_bit(i + MMF_DUMP_FILTER_SHIFT, &mm->flags); 2661 else 2662 clear_bit(i + MMF_DUMP_FILTER_SHIFT, &mm->flags); 2663 } 2664 2665 mmput(mm); 2666 out_no_mm: 2667 put_task_struct(task); 2668 out_no_task: 2669 if (ret < 0) 2670 return ret; 2671 return count; 2672 } 2673 2674 static const struct file_operations proc_coredump_filter_operations = { 2675 .read = proc_coredump_filter_read, 2676 .write = proc_coredump_filter_write, 2677 .llseek = generic_file_llseek, 2678 }; 2679 #endif 2680 2681 #ifdef CONFIG_TASK_IO_ACCOUNTING 2682 static int do_io_accounting(struct task_struct *task, struct seq_file *m, int whole) 2683 { 2684 struct task_io_accounting acct = task->ioac; 2685 unsigned long flags; 2686 int result; 2687 2688 result = mutex_lock_killable(&task->signal->cred_guard_mutex); 2689 if (result) 2690 return result; 2691 2692 if (!ptrace_may_access(task, PTRACE_MODE_READ_FSCREDS)) { 2693 result = -EACCES; 2694 goto out_unlock; 2695 } 2696 2697 if (whole && lock_task_sighand(task, &flags)) { 2698 struct task_struct *t = task; 2699 2700 task_io_accounting_add(&acct, &task->signal->ioac); 2701 while_each_thread(task, t) 2702 task_io_accounting_add(&acct, &t->ioac); 2703 2704 unlock_task_sighand(task, &flags); 2705 } 2706 seq_printf(m, 2707 "rchar: %llu\n" 2708 "wchar: %llu\n" 2709 "syscr: %llu\n" 2710 "syscw: %llu\n" 2711 "read_bytes: %llu\n" 2712 "write_bytes: %llu\n" 2713 "cancelled_write_bytes: %llu\n", 2714 (unsigned long long)acct.rchar, 2715 (unsigned long long)acct.wchar, 2716 (unsigned long long)acct.syscr, 2717 (unsigned long long)acct.syscw, 2718 (unsigned long long)acct.read_bytes, 2719 (unsigned long long)acct.write_bytes, 2720 (unsigned long long)acct.cancelled_write_bytes); 2721 result = 0; 2722 2723 out_unlock: 2724 mutex_unlock(&task->signal->cred_guard_mutex); 2725 return result; 2726 } 2727 2728 static int proc_tid_io_accounting(struct seq_file *m, struct pid_namespace *ns, 2729 struct pid *pid, struct task_struct *task) 2730 { 2731 return do_io_accounting(task, m, 0); 2732 } 2733 2734 static int proc_tgid_io_accounting(struct seq_file *m, struct pid_namespace *ns, 2735 struct pid *pid, struct task_struct *task) 2736 { 2737 return do_io_accounting(task, m, 1); 2738 } 2739 #endif /* CONFIG_TASK_IO_ACCOUNTING */ 2740 2741 #ifdef CONFIG_USER_NS 2742 static int proc_id_map_open(struct inode *inode, struct file *file, 2743 const struct seq_operations *seq_ops) 2744 { 2745 struct user_namespace *ns = NULL; 2746 struct task_struct *task; 2747 struct seq_file *seq; 2748 int ret = -EINVAL; 2749 2750 task = get_proc_task(inode); 2751 if (task) { 2752 rcu_read_lock(); 2753 ns = get_user_ns(task_cred_xxx(task, user_ns)); 2754 rcu_read_unlock(); 2755 put_task_struct(task); 2756 } 2757 if (!ns) 2758 goto err; 2759 2760 ret = seq_open(file, seq_ops); 2761 if (ret) 2762 goto err_put_ns; 2763 2764 seq = file->private_data; 2765 seq->private = ns; 2766 2767 return 0; 2768 err_put_ns: 2769 put_user_ns(ns); 2770 err: 2771 return ret; 2772 } 2773 2774 static int proc_id_map_release(struct inode *inode, struct file *file) 2775 { 2776 struct seq_file *seq = file->private_data; 2777 struct user_namespace *ns = seq->private; 2778 put_user_ns(ns); 2779 return seq_release(inode, file); 2780 } 2781 2782 static int proc_uid_map_open(struct inode *inode, struct file *file) 2783 { 2784 return proc_id_map_open(inode, file, &proc_uid_seq_operations); 2785 } 2786 2787 static int proc_gid_map_open(struct inode *inode, struct file *file) 2788 { 2789 return proc_id_map_open(inode, file, &proc_gid_seq_operations); 2790 } 2791 2792 static int proc_projid_map_open(struct inode *inode, struct file *file) 2793 { 2794 return proc_id_map_open(inode, file, &proc_projid_seq_operations); 2795 } 2796 2797 static const struct file_operations proc_uid_map_operations = { 2798 .open = proc_uid_map_open, 2799 .write = proc_uid_map_write, 2800 .read = seq_read, 2801 .llseek = seq_lseek, 2802 .release = proc_id_map_release, 2803 }; 2804 2805 static const struct file_operations proc_gid_map_operations = { 2806 .open = proc_gid_map_open, 2807 .write = proc_gid_map_write, 2808 .read = seq_read, 2809 .llseek = seq_lseek, 2810 .release = proc_id_map_release, 2811 }; 2812 2813 static const struct file_operations proc_projid_map_operations = { 2814 .open = proc_projid_map_open, 2815 .write = proc_projid_map_write, 2816 .read = seq_read, 2817 .llseek = seq_lseek, 2818 .release = proc_id_map_release, 2819 }; 2820 2821 static int proc_setgroups_open(struct inode *inode, struct file *file) 2822 { 2823 struct user_namespace *ns = NULL; 2824 struct task_struct *task; 2825 int ret; 2826 2827 ret = -ESRCH; 2828 task = get_proc_task(inode); 2829 if (task) { 2830 rcu_read_lock(); 2831 ns = get_user_ns(task_cred_xxx(task, user_ns)); 2832 rcu_read_unlock(); 2833 put_task_struct(task); 2834 } 2835 if (!ns) 2836 goto err; 2837 2838 if (file->f_mode & FMODE_WRITE) { 2839 ret = -EACCES; 2840 if (!ns_capable(ns, CAP_SYS_ADMIN)) 2841 goto err_put_ns; 2842 } 2843 2844 ret = single_open(file, &proc_setgroups_show, ns); 2845 if (ret) 2846 goto err_put_ns; 2847 2848 return 0; 2849 err_put_ns: 2850 put_user_ns(ns); 2851 err: 2852 return ret; 2853 } 2854 2855 static int proc_setgroups_release(struct inode *inode, struct file *file) 2856 { 2857 struct seq_file *seq = file->private_data; 2858 struct user_namespace *ns = seq->private; 2859 int ret = single_release(inode, file); 2860 put_user_ns(ns); 2861 return ret; 2862 } 2863 2864 static const struct file_operations proc_setgroups_operations = { 2865 .open = proc_setgroups_open, 2866 .write = proc_setgroups_write, 2867 .read = seq_read, 2868 .llseek = seq_lseek, 2869 .release = proc_setgroups_release, 2870 }; 2871 #endif /* CONFIG_USER_NS */ 2872 2873 static int proc_pid_personality(struct seq_file *m, struct pid_namespace *ns, 2874 struct pid *pid, struct task_struct *task) 2875 { 2876 int err = lock_trace(task); 2877 if (!err) { 2878 seq_printf(m, "%08x\n", task->personality); 2879 unlock_trace(task); 2880 } 2881 return err; 2882 } 2883 2884 #ifdef CONFIG_LIVEPATCH 2885 static int proc_pid_patch_state(struct seq_file *m, struct pid_namespace *ns, 2886 struct pid *pid, struct task_struct *task) 2887 { 2888 seq_printf(m, "%d\n", task->patch_state); 2889 return 0; 2890 } 2891 #endif /* CONFIG_LIVEPATCH */ 2892 2893 /* 2894 * Thread groups 2895 */ 2896 static const struct file_operations proc_task_operations; 2897 static const struct inode_operations proc_task_inode_operations; 2898 2899 static const struct pid_entry tgid_base_stuff[] = { 2900 DIR("task", S_IRUGO|S_IXUGO, proc_task_inode_operations, proc_task_operations), 2901 DIR("fd", S_IRUSR|S_IXUSR, proc_fd_inode_operations, proc_fd_operations), 2902 DIR("map_files", S_IRUSR|S_IXUSR, proc_map_files_inode_operations, proc_map_files_operations), 2903 DIR("fdinfo", S_IRUSR|S_IXUSR, proc_fdinfo_inode_operations, proc_fdinfo_operations), 2904 DIR("ns", S_IRUSR|S_IXUGO, proc_ns_dir_inode_operations, proc_ns_dir_operations), 2905 #ifdef CONFIG_NET 2906 DIR("net", S_IRUGO|S_IXUGO, proc_net_inode_operations, proc_net_operations), 2907 #endif 2908 REG("environ", S_IRUSR, proc_environ_operations), 2909 REG("auxv", S_IRUSR, proc_auxv_operations), 2910 ONE("status", S_IRUGO, proc_pid_status), 2911 ONE("personality", S_IRUSR, proc_pid_personality), 2912 ONE("limits", S_IRUGO, proc_pid_limits), 2913 #ifdef CONFIG_SCHED_DEBUG 2914 REG("sched", S_IRUGO|S_IWUSR, proc_pid_sched_operations), 2915 #endif 2916 #ifdef CONFIG_SCHED_AUTOGROUP 2917 REG("autogroup", S_IRUGO|S_IWUSR, proc_pid_sched_autogroup_operations), 2918 #endif 2919 REG("comm", S_IRUGO|S_IWUSR, proc_pid_set_comm_operations), 2920 #ifdef CONFIG_HAVE_ARCH_TRACEHOOK 2921 ONE("syscall", S_IRUSR, proc_pid_syscall), 2922 #endif 2923 REG("cmdline", S_IRUGO, proc_pid_cmdline_ops), 2924 ONE("stat", S_IRUGO, proc_tgid_stat), 2925 ONE("statm", S_IRUGO, proc_pid_statm), 2926 REG("maps", S_IRUGO, proc_pid_maps_operations), 2927 #ifdef CONFIG_NUMA 2928 REG("numa_maps", S_IRUGO, proc_pid_numa_maps_operations), 2929 #endif 2930 REG("mem", S_IRUSR|S_IWUSR, proc_mem_operations), 2931 LNK("cwd", proc_cwd_link), 2932 LNK("root", proc_root_link), 2933 LNK("exe", proc_exe_link), 2934 REG("mounts", S_IRUGO, proc_mounts_operations), 2935 REG("mountinfo", S_IRUGO, proc_mountinfo_operations), 2936 REG("mountstats", S_IRUSR, proc_mountstats_operations), 2937 #ifdef CONFIG_PROC_PAGE_MONITOR 2938 REG("clear_refs", S_IWUSR, proc_clear_refs_operations), 2939 REG("smaps", S_IRUGO, proc_pid_smaps_operations), 2940 REG("smaps_rollup", S_IRUGO, proc_pid_smaps_rollup_operations), 2941 REG("pagemap", S_IRUSR, proc_pagemap_operations), 2942 #endif 2943 #ifdef CONFIG_SECURITY 2944 DIR("attr", S_IRUGO|S_IXUGO, proc_attr_dir_inode_operations, proc_attr_dir_operations), 2945 #endif 2946 #ifdef CONFIG_KALLSYMS 2947 ONE("wchan", S_IRUGO, proc_pid_wchan), 2948 #endif 2949 #ifdef CONFIG_STACKTRACE 2950 ONE("stack", S_IRUSR, proc_pid_stack), 2951 #endif 2952 #ifdef CONFIG_SCHED_INFO 2953 ONE("schedstat", S_IRUGO, proc_pid_schedstat), 2954 #endif 2955 #ifdef CONFIG_LATENCYTOP 2956 REG("latency", S_IRUGO, proc_lstats_operations), 2957 #endif 2958 #ifdef CONFIG_PROC_PID_CPUSET 2959 ONE("cpuset", S_IRUGO, proc_cpuset_show), 2960 #endif 2961 #ifdef CONFIG_CGROUPS 2962 ONE("cgroup", S_IRUGO, proc_cgroup_show), 2963 #endif 2964 ONE("oom_score", S_IRUGO, proc_oom_score), 2965 REG("oom_adj", S_IRUGO|S_IWUSR, proc_oom_adj_operations), 2966 REG("oom_score_adj", S_IRUGO|S_IWUSR, proc_oom_score_adj_operations), 2967 #ifdef CONFIG_AUDITSYSCALL 2968 REG("loginuid", S_IWUSR|S_IRUGO, proc_loginuid_operations), 2969 REG("sessionid", S_IRUGO, proc_sessionid_operations), 2970 #endif 2971 #ifdef CONFIG_FAULT_INJECTION 2972 REG("make-it-fail", S_IRUGO|S_IWUSR, proc_fault_inject_operations), 2973 REG("fail-nth", 0644, proc_fail_nth_operations), 2974 #endif 2975 #ifdef CONFIG_ELF_CORE 2976 REG("coredump_filter", S_IRUGO|S_IWUSR, proc_coredump_filter_operations), 2977 #endif 2978 #ifdef CONFIG_TASK_IO_ACCOUNTING 2979 ONE("io", S_IRUSR, proc_tgid_io_accounting), 2980 #endif 2981 #ifdef CONFIG_USER_NS 2982 REG("uid_map", S_IRUGO|S_IWUSR, proc_uid_map_operations), 2983 REG("gid_map", S_IRUGO|S_IWUSR, proc_gid_map_operations), 2984 REG("projid_map", S_IRUGO|S_IWUSR, proc_projid_map_operations), 2985 REG("setgroups", S_IRUGO|S_IWUSR, proc_setgroups_operations), 2986 #endif 2987 #if defined(CONFIG_CHECKPOINT_RESTORE) && defined(CONFIG_POSIX_TIMERS) 2988 REG("timers", S_IRUGO, proc_timers_operations), 2989 #endif 2990 REG("timerslack_ns", S_IRUGO|S_IWUGO, proc_pid_set_timerslack_ns_operations), 2991 #ifdef CONFIG_LIVEPATCH 2992 ONE("patch_state", S_IRUSR, proc_pid_patch_state), 2993 #endif 2994 }; 2995 2996 static int proc_tgid_base_readdir(struct file *file, struct dir_context *ctx) 2997 { 2998 return proc_pident_readdir(file, ctx, 2999 tgid_base_stuff, ARRAY_SIZE(tgid_base_stuff)); 3000 } 3001 3002 static const struct file_operations proc_tgid_base_operations = { 3003 .read = generic_read_dir, 3004 .iterate_shared = proc_tgid_base_readdir, 3005 .llseek = generic_file_llseek, 3006 }; 3007 3008 static struct dentry *proc_tgid_base_lookup(struct inode *dir, struct dentry *dentry, unsigned int flags) 3009 { 3010 return proc_pident_lookup(dir, dentry, 3011 tgid_base_stuff, ARRAY_SIZE(tgid_base_stuff)); 3012 } 3013 3014 static const struct inode_operations proc_tgid_base_inode_operations = { 3015 .lookup = proc_tgid_base_lookup, 3016 .getattr = pid_getattr, 3017 .setattr = proc_setattr, 3018 .permission = proc_pid_permission, 3019 }; 3020 3021 static void proc_flush_task_mnt(struct vfsmount *mnt, pid_t pid, pid_t tgid) 3022 { 3023 struct dentry *dentry, *leader, *dir; 3024 char buf[10 + 1]; 3025 struct qstr name; 3026 3027 name.name = buf; 3028 name.len = snprintf(buf, sizeof(buf), "%u", pid); 3029 /* no ->d_hash() rejects on procfs */ 3030 dentry = d_hash_and_lookup(mnt->mnt_root, &name); 3031 if (dentry) { 3032 d_invalidate(dentry); 3033 dput(dentry); 3034 } 3035 3036 if (pid == tgid) 3037 return; 3038 3039 name.name = buf; 3040 name.len = snprintf(buf, sizeof(buf), "%u", tgid); 3041 leader = d_hash_and_lookup(mnt->mnt_root, &name); 3042 if (!leader) 3043 goto out; 3044 3045 name.name = "task"; 3046 name.len = strlen(name.name); 3047 dir = d_hash_and_lookup(leader, &name); 3048 if (!dir) 3049 goto out_put_leader; 3050 3051 name.name = buf; 3052 name.len = snprintf(buf, sizeof(buf), "%u", pid); 3053 dentry = d_hash_and_lookup(dir, &name); 3054 if (dentry) { 3055 d_invalidate(dentry); 3056 dput(dentry); 3057 } 3058 3059 dput(dir); 3060 out_put_leader: 3061 dput(leader); 3062 out: 3063 return; 3064 } 3065 3066 /** 3067 * proc_flush_task - Remove dcache entries for @task from the /proc dcache. 3068 * @task: task that should be flushed. 3069 * 3070 * When flushing dentries from proc, one needs to flush them from global 3071 * proc (proc_mnt) and from all the namespaces' procs this task was seen 3072 * in. This call is supposed to do all of this job. 3073 * 3074 * Looks in the dcache for 3075 * /proc/@pid 3076 * /proc/@tgid/task/@pid 3077 * if either directory is present flushes it and all of it'ts children 3078 * from the dcache. 3079 * 3080 * It is safe and reasonable to cache /proc entries for a task until 3081 * that task exits. After that they just clog up the dcache with 3082 * useless entries, possibly causing useful dcache entries to be 3083 * flushed instead. This routine is proved to flush those useless 3084 * dcache entries at process exit time. 3085 * 3086 * NOTE: This routine is just an optimization so it does not guarantee 3087 * that no dcache entries will exist at process exit time it 3088 * just makes it very unlikely that any will persist. 3089 */ 3090 3091 void proc_flush_task(struct task_struct *task) 3092 { 3093 int i; 3094 struct pid *pid, *tgid; 3095 struct upid *upid; 3096 3097 pid = task_pid(task); 3098 tgid = task_tgid(task); 3099 3100 for (i = 0; i <= pid->level; i++) { 3101 upid = &pid->numbers[i]; 3102 proc_flush_task_mnt(upid->ns->proc_mnt, upid->nr, 3103 tgid->numbers[i].nr); 3104 } 3105 } 3106 3107 static struct dentry *proc_pid_instantiate(struct dentry * dentry, 3108 struct task_struct *task, const void *ptr) 3109 { 3110 struct inode *inode; 3111 3112 inode = proc_pid_make_inode(dentry->d_sb, task, S_IFDIR | S_IRUGO | S_IXUGO); 3113 if (!inode) 3114 return ERR_PTR(-ENOENT); 3115 3116 inode->i_op = &proc_tgid_base_inode_operations; 3117 inode->i_fop = &proc_tgid_base_operations; 3118 inode->i_flags|=S_IMMUTABLE; 3119 3120 set_nlink(inode, nlink_tgid); 3121 pid_update_inode(task, inode); 3122 3123 d_set_d_op(dentry, &pid_dentry_operations); 3124 return d_splice_alias(inode, dentry); 3125 } 3126 3127 struct dentry *proc_pid_lookup(struct inode *dir, struct dentry * dentry, unsigned int flags) 3128 { 3129 struct task_struct *task; 3130 unsigned tgid; 3131 struct pid_namespace *ns; 3132 struct dentry *result = ERR_PTR(-ENOENT); 3133 3134 tgid = name_to_int(&dentry->d_name); 3135 if (tgid == ~0U) 3136 goto out; 3137 3138 ns = dentry->d_sb->s_fs_info; 3139 rcu_read_lock(); 3140 task = find_task_by_pid_ns(tgid, ns); 3141 if (task) 3142 get_task_struct(task); 3143 rcu_read_unlock(); 3144 if (!task) 3145 goto out; 3146 3147 result = proc_pid_instantiate(dentry, task, NULL); 3148 put_task_struct(task); 3149 out: 3150 return result; 3151 } 3152 3153 /* 3154 * Find the first task with tgid >= tgid 3155 * 3156 */ 3157 struct tgid_iter { 3158 unsigned int tgid; 3159 struct task_struct *task; 3160 }; 3161 static struct tgid_iter next_tgid(struct pid_namespace *ns, struct tgid_iter iter) 3162 { 3163 struct pid *pid; 3164 3165 if (iter.task) 3166 put_task_struct(iter.task); 3167 rcu_read_lock(); 3168 retry: 3169 iter.task = NULL; 3170 pid = find_ge_pid(iter.tgid, ns); 3171 if (pid) { 3172 iter.tgid = pid_nr_ns(pid, ns); 3173 iter.task = pid_task(pid, PIDTYPE_PID); 3174 /* What we to know is if the pid we have find is the 3175 * pid of a thread_group_leader. Testing for task 3176 * being a thread_group_leader is the obvious thing 3177 * todo but there is a window when it fails, due to 3178 * the pid transfer logic in de_thread. 3179 * 3180 * So we perform the straight forward test of seeing 3181 * if the pid we have found is the pid of a thread 3182 * group leader, and don't worry if the task we have 3183 * found doesn't happen to be a thread group leader. 3184 * As we don't care in the case of readdir. 3185 */ 3186 if (!iter.task || !has_group_leader_pid(iter.task)) { 3187 iter.tgid += 1; 3188 goto retry; 3189 } 3190 get_task_struct(iter.task); 3191 } 3192 rcu_read_unlock(); 3193 return iter; 3194 } 3195 3196 #define TGID_OFFSET (FIRST_PROCESS_ENTRY + 2) 3197 3198 /* for the /proc/ directory itself, after non-process stuff has been done */ 3199 int proc_pid_readdir(struct file *file, struct dir_context *ctx) 3200 { 3201 struct tgid_iter iter; 3202 struct pid_namespace *ns = proc_pid_ns(file_inode(file)); 3203 loff_t pos = ctx->pos; 3204 3205 if (pos >= PID_MAX_LIMIT + TGID_OFFSET) 3206 return 0; 3207 3208 if (pos == TGID_OFFSET - 2) { 3209 struct inode *inode = d_inode(ns->proc_self); 3210 if (!dir_emit(ctx, "self", 4, inode->i_ino, DT_LNK)) 3211 return 0; 3212 ctx->pos = pos = pos + 1; 3213 } 3214 if (pos == TGID_OFFSET - 1) { 3215 struct inode *inode = d_inode(ns->proc_thread_self); 3216 if (!dir_emit(ctx, "thread-self", 11, inode->i_ino, DT_LNK)) 3217 return 0; 3218 ctx->pos = pos = pos + 1; 3219 } 3220 iter.tgid = pos - TGID_OFFSET; 3221 iter.task = NULL; 3222 for (iter = next_tgid(ns, iter); 3223 iter.task; 3224 iter.tgid += 1, iter = next_tgid(ns, iter)) { 3225 char name[10 + 1]; 3226 unsigned int len; 3227 3228 cond_resched(); 3229 if (!has_pid_permissions(ns, iter.task, HIDEPID_INVISIBLE)) 3230 continue; 3231 3232 len = snprintf(name, sizeof(name), "%u", iter.tgid); 3233 ctx->pos = iter.tgid + TGID_OFFSET; 3234 if (!proc_fill_cache(file, ctx, name, len, 3235 proc_pid_instantiate, iter.task, NULL)) { 3236 put_task_struct(iter.task); 3237 return 0; 3238 } 3239 } 3240 ctx->pos = PID_MAX_LIMIT + TGID_OFFSET; 3241 return 0; 3242 } 3243 3244 /* 3245 * proc_tid_comm_permission is a special permission function exclusively 3246 * used for the node /proc/<pid>/task/<tid>/comm. 3247 * It bypasses generic permission checks in the case where a task of the same 3248 * task group attempts to access the node. 3249 * The rationale behind this is that glibc and bionic access this node for 3250 * cross thread naming (pthread_set/getname_np(!self)). However, if 3251 * PR_SET_DUMPABLE gets set to 0 this node among others becomes uid=0 gid=0, 3252 * which locks out the cross thread naming implementation. 3253 * This function makes sure that the node is always accessible for members of 3254 * same thread group. 3255 */ 3256 static int proc_tid_comm_permission(struct inode *inode, int mask) 3257 { 3258 bool is_same_tgroup; 3259 struct task_struct *task; 3260 3261 task = get_proc_task(inode); 3262 if (!task) 3263 return -ESRCH; 3264 is_same_tgroup = same_thread_group(current, task); 3265 put_task_struct(task); 3266 3267 if (likely(is_same_tgroup && !(mask & MAY_EXEC))) { 3268 /* This file (/proc/<pid>/task/<tid>/comm) can always be 3269 * read or written by the members of the corresponding 3270 * thread group. 3271 */ 3272 return 0; 3273 } 3274 3275 return generic_permission(inode, mask); 3276 } 3277 3278 static const struct inode_operations proc_tid_comm_inode_operations = { 3279 .permission = proc_tid_comm_permission, 3280 }; 3281 3282 /* 3283 * Tasks 3284 */ 3285 static const struct pid_entry tid_base_stuff[] = { 3286 DIR("fd", S_IRUSR|S_IXUSR, proc_fd_inode_operations, proc_fd_operations), 3287 DIR("fdinfo", S_IRUSR|S_IXUSR, proc_fdinfo_inode_operations, proc_fdinfo_operations), 3288 DIR("ns", S_IRUSR|S_IXUGO, proc_ns_dir_inode_operations, proc_ns_dir_operations), 3289 #ifdef CONFIG_NET 3290 DIR("net", S_IRUGO|S_IXUGO, proc_net_inode_operations, proc_net_operations), 3291 #endif 3292 REG("environ", S_IRUSR, proc_environ_operations), 3293 REG("auxv", S_IRUSR, proc_auxv_operations), 3294 ONE("status", S_IRUGO, proc_pid_status), 3295 ONE("personality", S_IRUSR, proc_pid_personality), 3296 ONE("limits", S_IRUGO, proc_pid_limits), 3297 #ifdef CONFIG_SCHED_DEBUG 3298 REG("sched", S_IRUGO|S_IWUSR, proc_pid_sched_operations), 3299 #endif 3300 NOD("comm", S_IFREG|S_IRUGO|S_IWUSR, 3301 &proc_tid_comm_inode_operations, 3302 &proc_pid_set_comm_operations, {}), 3303 #ifdef CONFIG_HAVE_ARCH_TRACEHOOK 3304 ONE("syscall", S_IRUSR, proc_pid_syscall), 3305 #endif 3306 REG("cmdline", S_IRUGO, proc_pid_cmdline_ops), 3307 ONE("stat", S_IRUGO, proc_tid_stat), 3308 ONE("statm", S_IRUGO, proc_pid_statm), 3309 REG("maps", S_IRUGO, proc_tid_maps_operations), 3310 #ifdef CONFIG_PROC_CHILDREN 3311 REG("children", S_IRUGO, proc_tid_children_operations), 3312 #endif 3313 #ifdef CONFIG_NUMA 3314 REG("numa_maps", S_IRUGO, proc_tid_numa_maps_operations), 3315 #endif 3316 REG("mem", S_IRUSR|S_IWUSR, proc_mem_operations), 3317 LNK("cwd", proc_cwd_link), 3318 LNK("root", proc_root_link), 3319 LNK("exe", proc_exe_link), 3320 REG("mounts", S_IRUGO, proc_mounts_operations), 3321 REG("mountinfo", S_IRUGO, proc_mountinfo_operations), 3322 #ifdef CONFIG_PROC_PAGE_MONITOR 3323 REG("clear_refs", S_IWUSR, proc_clear_refs_operations), 3324 REG("smaps", S_IRUGO, proc_tid_smaps_operations), 3325 REG("smaps_rollup", S_IRUGO, proc_pid_smaps_rollup_operations), 3326 REG("pagemap", S_IRUSR, proc_pagemap_operations), 3327 #endif 3328 #ifdef CONFIG_SECURITY 3329 DIR("attr", S_IRUGO|S_IXUGO, proc_attr_dir_inode_operations, proc_attr_dir_operations), 3330 #endif 3331 #ifdef CONFIG_KALLSYMS 3332 ONE("wchan", S_IRUGO, proc_pid_wchan), 3333 #endif 3334 #ifdef CONFIG_STACKTRACE 3335 ONE("stack", S_IRUSR, proc_pid_stack), 3336 #endif 3337 #ifdef CONFIG_SCHED_INFO 3338 ONE("schedstat", S_IRUGO, proc_pid_schedstat), 3339 #endif 3340 #ifdef CONFIG_LATENCYTOP 3341 REG("latency", S_IRUGO, proc_lstats_operations), 3342 #endif 3343 #ifdef CONFIG_PROC_PID_CPUSET 3344 ONE("cpuset", S_IRUGO, proc_cpuset_show), 3345 #endif 3346 #ifdef CONFIG_CGROUPS 3347 ONE("cgroup", S_IRUGO, proc_cgroup_show), 3348 #endif 3349 ONE("oom_score", S_IRUGO, proc_oom_score), 3350 REG("oom_adj", S_IRUGO|S_IWUSR, proc_oom_adj_operations), 3351 REG("oom_score_adj", S_IRUGO|S_IWUSR, proc_oom_score_adj_operations), 3352 #ifdef CONFIG_AUDITSYSCALL 3353 REG("loginuid", S_IWUSR|S_IRUGO, proc_loginuid_operations), 3354 REG("sessionid", S_IRUGO, proc_sessionid_operations), 3355 #endif 3356 #ifdef CONFIG_FAULT_INJECTION 3357 REG("make-it-fail", S_IRUGO|S_IWUSR, proc_fault_inject_operations), 3358 REG("fail-nth", 0644, proc_fail_nth_operations), 3359 #endif 3360 #ifdef CONFIG_TASK_IO_ACCOUNTING 3361 ONE("io", S_IRUSR, proc_tid_io_accounting), 3362 #endif 3363 #ifdef CONFIG_USER_NS 3364 REG("uid_map", S_IRUGO|S_IWUSR, proc_uid_map_operations), 3365 REG("gid_map", S_IRUGO|S_IWUSR, proc_gid_map_operations), 3366 REG("projid_map", S_IRUGO|S_IWUSR, proc_projid_map_operations), 3367 REG("setgroups", S_IRUGO|S_IWUSR, proc_setgroups_operations), 3368 #endif 3369 #ifdef CONFIG_LIVEPATCH 3370 ONE("patch_state", S_IRUSR, proc_pid_patch_state), 3371 #endif 3372 }; 3373 3374 static int proc_tid_base_readdir(struct file *file, struct dir_context *ctx) 3375 { 3376 return proc_pident_readdir(file, ctx, 3377 tid_base_stuff, ARRAY_SIZE(tid_base_stuff)); 3378 } 3379 3380 static struct dentry *proc_tid_base_lookup(struct inode *dir, struct dentry *dentry, unsigned int flags) 3381 { 3382 return proc_pident_lookup(dir, dentry, 3383 tid_base_stuff, ARRAY_SIZE(tid_base_stuff)); 3384 } 3385 3386 static const struct file_operations proc_tid_base_operations = { 3387 .read = generic_read_dir, 3388 .iterate_shared = proc_tid_base_readdir, 3389 .llseek = generic_file_llseek, 3390 }; 3391 3392 static const struct inode_operations proc_tid_base_inode_operations = { 3393 .lookup = proc_tid_base_lookup, 3394 .getattr = pid_getattr, 3395 .setattr = proc_setattr, 3396 }; 3397 3398 static struct dentry *proc_task_instantiate(struct dentry *dentry, 3399 struct task_struct *task, const void *ptr) 3400 { 3401 struct inode *inode; 3402 inode = proc_pid_make_inode(dentry->d_sb, task, S_IFDIR | S_IRUGO | S_IXUGO); 3403 if (!inode) 3404 return ERR_PTR(-ENOENT); 3405 3406 inode->i_op = &proc_tid_base_inode_operations; 3407 inode->i_fop = &proc_tid_base_operations; 3408 inode->i_flags |= S_IMMUTABLE; 3409 3410 set_nlink(inode, nlink_tid); 3411 pid_update_inode(task, inode); 3412 3413 d_set_d_op(dentry, &pid_dentry_operations); 3414 return d_splice_alias(inode, dentry); 3415 } 3416 3417 static struct dentry *proc_task_lookup(struct inode *dir, struct dentry * dentry, unsigned int flags) 3418 { 3419 struct task_struct *task; 3420 struct task_struct *leader = get_proc_task(dir); 3421 unsigned tid; 3422 struct pid_namespace *ns; 3423 struct dentry *result = ERR_PTR(-ENOENT); 3424 3425 if (!leader) 3426 goto out_no_task; 3427 3428 tid = name_to_int(&dentry->d_name); 3429 if (tid == ~0U) 3430 goto out; 3431 3432 ns = dentry->d_sb->s_fs_info; 3433 rcu_read_lock(); 3434 task = find_task_by_pid_ns(tid, ns); 3435 if (task) 3436 get_task_struct(task); 3437 rcu_read_unlock(); 3438 if (!task) 3439 goto out; 3440 if (!same_thread_group(leader, task)) 3441 goto out_drop_task; 3442 3443 result = proc_task_instantiate(dentry, task, NULL); 3444 out_drop_task: 3445 put_task_struct(task); 3446 out: 3447 put_task_struct(leader); 3448 out_no_task: 3449 return result; 3450 } 3451 3452 /* 3453 * Find the first tid of a thread group to return to user space. 3454 * 3455 * Usually this is just the thread group leader, but if the users 3456 * buffer was too small or there was a seek into the middle of the 3457 * directory we have more work todo. 3458 * 3459 * In the case of a short read we start with find_task_by_pid. 3460 * 3461 * In the case of a seek we start with the leader and walk nr 3462 * threads past it. 3463 */ 3464 static struct task_struct *first_tid(struct pid *pid, int tid, loff_t f_pos, 3465 struct pid_namespace *ns) 3466 { 3467 struct task_struct *pos, *task; 3468 unsigned long nr = f_pos; 3469 3470 if (nr != f_pos) /* 32bit overflow? */ 3471 return NULL; 3472 3473 rcu_read_lock(); 3474 task = pid_task(pid, PIDTYPE_PID); 3475 if (!task) 3476 goto fail; 3477 3478 /* Attempt to start with the tid of a thread */ 3479 if (tid && nr) { 3480 pos = find_task_by_pid_ns(tid, ns); 3481 if (pos && same_thread_group(pos, task)) 3482 goto found; 3483 } 3484 3485 /* If nr exceeds the number of threads there is nothing todo */ 3486 if (nr >= get_nr_threads(task)) 3487 goto fail; 3488 3489 /* If we haven't found our starting place yet start 3490 * with the leader and walk nr threads forward. 3491 */ 3492 pos = task = task->group_leader; 3493 do { 3494 if (!nr--) 3495 goto found; 3496 } while_each_thread(task, pos); 3497 fail: 3498 pos = NULL; 3499 goto out; 3500 found: 3501 get_task_struct(pos); 3502 out: 3503 rcu_read_unlock(); 3504 return pos; 3505 } 3506 3507 /* 3508 * Find the next thread in the thread list. 3509 * Return NULL if there is an error or no next thread. 3510 * 3511 * The reference to the input task_struct is released. 3512 */ 3513 static struct task_struct *next_tid(struct task_struct *start) 3514 { 3515 struct task_struct *pos = NULL; 3516 rcu_read_lock(); 3517 if (pid_alive(start)) { 3518 pos = next_thread(start); 3519 if (thread_group_leader(pos)) 3520 pos = NULL; 3521 else 3522 get_task_struct(pos); 3523 } 3524 rcu_read_unlock(); 3525 put_task_struct(start); 3526 return pos; 3527 } 3528 3529 /* for the /proc/TGID/task/ directories */ 3530 static int proc_task_readdir(struct file *file, struct dir_context *ctx) 3531 { 3532 struct inode *inode = file_inode(file); 3533 struct task_struct *task; 3534 struct pid_namespace *ns; 3535 int tid; 3536 3537 if (proc_inode_is_dead(inode)) 3538 return -ENOENT; 3539 3540 if (!dir_emit_dots(file, ctx)) 3541 return 0; 3542 3543 /* f_version caches the tgid value that the last readdir call couldn't 3544 * return. lseek aka telldir automagically resets f_version to 0. 3545 */ 3546 ns = proc_pid_ns(inode); 3547 tid = (int)file->f_version; 3548 file->f_version = 0; 3549 for (task = first_tid(proc_pid(inode), tid, ctx->pos - 2, ns); 3550 task; 3551 task = next_tid(task), ctx->pos++) { 3552 char name[10 + 1]; 3553 unsigned int len; 3554 tid = task_pid_nr_ns(task, ns); 3555 len = snprintf(name, sizeof(name), "%u", tid); 3556 if (!proc_fill_cache(file, ctx, name, len, 3557 proc_task_instantiate, task, NULL)) { 3558 /* returning this tgid failed, save it as the first 3559 * pid for the next readir call */ 3560 file->f_version = (u64)tid; 3561 put_task_struct(task); 3562 break; 3563 } 3564 } 3565 3566 return 0; 3567 } 3568 3569 static int proc_task_getattr(const struct path *path, struct kstat *stat, 3570 u32 request_mask, unsigned int query_flags) 3571 { 3572 struct inode *inode = d_inode(path->dentry); 3573 struct task_struct *p = get_proc_task(inode); 3574 generic_fillattr(inode, stat); 3575 3576 if (p) { 3577 stat->nlink += get_nr_threads(p); 3578 put_task_struct(p); 3579 } 3580 3581 return 0; 3582 } 3583 3584 static const struct inode_operations proc_task_inode_operations = { 3585 .lookup = proc_task_lookup, 3586 .getattr = proc_task_getattr, 3587 .setattr = proc_setattr, 3588 .permission = proc_pid_permission, 3589 }; 3590 3591 static const struct file_operations proc_task_operations = { 3592 .read = generic_read_dir, 3593 .iterate_shared = proc_task_readdir, 3594 .llseek = generic_file_llseek, 3595 }; 3596 3597 void __init set_proc_pid_nlink(void) 3598 { 3599 nlink_tid = pid_entry_nlink(tid_base_stuff, ARRAY_SIZE(tid_base_stuff)); 3600 nlink_tgid = pid_entry_nlink(tgid_base_stuff, ARRAY_SIZE(tgid_base_stuff)); 3601 } 3602