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