1 /* 2 * linux/fs/proc/base.c 3 * 4 * Copyright (C) 1991, 1992 Linus Torvalds 5 * 6 * proc base directory handling functions 7 * 8 * 1999, Al Viro. Rewritten. Now it covers the whole per-process part. 9 * Instead of using magical inumbers to determine the kind of object 10 * we allocate and fill in-core inodes upon lookup. They don't even 11 * go into icache. We cache the reference to task_struct upon lookup too. 12 * Eventually it should become a filesystem in its own. We don't use the 13 * rest of procfs anymore. 14 * 15 * 16 * Changelog: 17 * 17-Jan-2005 18 * Allan Bezerra 19 * Bruna Moreira <bruna.moreira@indt.org.br> 20 * Edjard Mota <edjard.mota@indt.org.br> 21 * Ilias Biris <ilias.biris@indt.org.br> 22 * Mauricio Lin <mauricio.lin@indt.org.br> 23 * 24 * Embedded Linux Lab - 10LE Instituto Nokia de Tecnologia - INdT 25 * 26 * A new process specific entry (smaps) included in /proc. It shows the 27 * size of rss for each memory area. The maps entry lacks information 28 * about physical memory size (rss) for each mapped file, i.e., 29 * rss information for executables and library files. 30 * This additional information is useful for any tools that need to know 31 * about physical memory consumption for a process specific library. 32 * 33 * Changelog: 34 * 21-Feb-2005 35 * Embedded Linux Lab - 10LE Instituto Nokia de Tecnologia - INdT 36 * Pud inclusion in the page table walking. 37 * 38 * ChangeLog: 39 * 10-Mar-2005 40 * 10LE Instituto Nokia de Tecnologia - INdT: 41 * A better way to walks through the page table as suggested by Hugh Dickins. 42 * 43 * Simo Piiroinen <simo.piiroinen@nokia.com>: 44 * Smaps information related to shared, private, clean and dirty pages. 45 * 46 * Paul Mundt <paul.mundt@nokia.com>: 47 * Overall revision about smaps. 48 */ 49 50 #include <asm/uaccess.h> 51 52 #include <linux/errno.h> 53 #include <linux/time.h> 54 #include <linux/proc_fs.h> 55 #include <linux/stat.h> 56 #include <linux/task_io_accounting_ops.h> 57 #include <linux/init.h> 58 #include <linux/capability.h> 59 #include <linux/file.h> 60 #include <linux/fdtable.h> 61 #include <linux/string.h> 62 #include <linux/seq_file.h> 63 #include <linux/namei.h> 64 #include <linux/mnt_namespace.h> 65 #include <linux/mm.h> 66 #include <linux/swap.h> 67 #include <linux/rcupdate.h> 68 #include <linux/kallsyms.h> 69 #include <linux/stacktrace.h> 70 #include <linux/resource.h> 71 #include <linux/module.h> 72 #include <linux/mount.h> 73 #include <linux/security.h> 74 #include <linux/ptrace.h> 75 #include <linux/tracehook.h> 76 #include <linux/printk.h> 77 #include <linux/cgroup.h> 78 #include <linux/cpuset.h> 79 #include <linux/audit.h> 80 #include <linux/poll.h> 81 #include <linux/nsproxy.h> 82 #include <linux/oom.h> 83 #include <linux/elf.h> 84 #include <linux/pid_namespace.h> 85 #include <linux/user_namespace.h> 86 #include <linux/fs_struct.h> 87 #include <linux/slab.h> 88 #include <linux/flex_array.h> 89 #include <linux/posix-timers.h> 90 #ifdef CONFIG_HARDWALL 91 #include <asm/hardwall.h> 92 #endif 93 #include <trace/events/oom.h> 94 #include "internal.h" 95 #include "fd.h" 96 97 /* NOTE: 98 * Implementing inode permission operations in /proc is almost 99 * certainly an error. Permission checks need to happen during 100 * each system call not at open time. The reason is that most of 101 * what we wish to check for permissions in /proc varies at runtime. 102 * 103 * The classic example of a problem is opening file descriptors 104 * in /proc for a task before it execs a suid executable. 105 */ 106 107 struct pid_entry { 108 const char *name; 109 int len; 110 umode_t mode; 111 const struct inode_operations *iop; 112 const struct file_operations *fop; 113 union proc_op op; 114 }; 115 116 #define NOD(NAME, MODE, IOP, FOP, OP) { \ 117 .name = (NAME), \ 118 .len = sizeof(NAME) - 1, \ 119 .mode = MODE, \ 120 .iop = IOP, \ 121 .fop = FOP, \ 122 .op = OP, \ 123 } 124 125 #define DIR(NAME, MODE, iops, fops) \ 126 NOD(NAME, (S_IFDIR|(MODE)), &iops, &fops, {} ) 127 #define LNK(NAME, get_link) \ 128 NOD(NAME, (S_IFLNK|S_IRWXUGO), \ 129 &proc_pid_link_inode_operations, NULL, \ 130 { .proc_get_link = get_link } ) 131 #define REG(NAME, MODE, fops) \ 132 NOD(NAME, (S_IFREG|(MODE)), NULL, &fops, {}) 133 #define ONE(NAME, MODE, show) \ 134 NOD(NAME, (S_IFREG|(MODE)), \ 135 NULL, &proc_single_file_operations, \ 136 { .proc_show = show } ) 137 138 /* 139 * Count the number of hardlinks for the pid_entry table, excluding the . 140 * and .. links. 141 */ 142 static unsigned int pid_entry_count_dirs(const struct pid_entry *entries, 143 unsigned int n) 144 { 145 unsigned int i; 146 unsigned int count; 147 148 count = 0; 149 for (i = 0; i < n; ++i) { 150 if (S_ISDIR(entries[i].mode)) 151 ++count; 152 } 153 154 return count; 155 } 156 157 static int get_task_root(struct task_struct *task, struct path *root) 158 { 159 int result = -ENOENT; 160 161 task_lock(task); 162 if (task->fs) { 163 get_fs_root(task->fs, root); 164 result = 0; 165 } 166 task_unlock(task); 167 return result; 168 } 169 170 static int proc_cwd_link(struct dentry *dentry, struct path *path) 171 { 172 struct task_struct *task = get_proc_task(d_inode(dentry)); 173 int result = -ENOENT; 174 175 if (task) { 176 task_lock(task); 177 if (task->fs) { 178 get_fs_pwd(task->fs, path); 179 result = 0; 180 } 181 task_unlock(task); 182 put_task_struct(task); 183 } 184 return result; 185 } 186 187 static int proc_root_link(struct dentry *dentry, struct path *path) 188 { 189 struct task_struct *task = get_proc_task(d_inode(dentry)); 190 int result = -ENOENT; 191 192 if (task) { 193 result = get_task_root(task, path); 194 put_task_struct(task); 195 } 196 return result; 197 } 198 199 static ssize_t proc_pid_cmdline_read(struct file *file, char __user *buf, 200 size_t _count, loff_t *pos) 201 { 202 struct task_struct *tsk; 203 struct mm_struct *mm; 204 char *page; 205 unsigned long count = _count; 206 unsigned long arg_start, arg_end, env_start, env_end; 207 unsigned long len1, len2, len; 208 unsigned long p; 209 char c; 210 ssize_t rv; 211 212 BUG_ON(*pos < 0); 213 214 tsk = get_proc_task(file_inode(file)); 215 if (!tsk) 216 return -ESRCH; 217 mm = get_task_mm(tsk); 218 put_task_struct(tsk); 219 if (!mm) 220 return 0; 221 /* Check if process spawned far enough to have cmdline. */ 222 if (!mm->env_end) { 223 rv = 0; 224 goto out_mmput; 225 } 226 227 page = (char *)__get_free_page(GFP_TEMPORARY); 228 if (!page) { 229 rv = -ENOMEM; 230 goto out_mmput; 231 } 232 233 down_read(&mm->mmap_sem); 234 arg_start = mm->arg_start; 235 arg_end = mm->arg_end; 236 env_start = mm->env_start; 237 env_end = mm->env_end; 238 up_read(&mm->mmap_sem); 239 240 BUG_ON(arg_start > arg_end); 241 BUG_ON(env_start > env_end); 242 243 len1 = arg_end - arg_start; 244 len2 = env_end - env_start; 245 246 /* Empty ARGV. */ 247 if (len1 == 0) { 248 rv = 0; 249 goto out_free_page; 250 } 251 /* 252 * Inherently racy -- command line shares address space 253 * with code and data. 254 */ 255 rv = access_remote_vm(mm, arg_end - 1, &c, 1, 0); 256 if (rv <= 0) 257 goto out_free_page; 258 259 rv = 0; 260 261 if (c == '\0') { 262 /* Command line (set of strings) occupies whole ARGV. */ 263 if (len1 <= *pos) 264 goto out_free_page; 265 266 p = arg_start + *pos; 267 len = len1 - *pos; 268 while (count > 0 && len > 0) { 269 unsigned int _count; 270 int nr_read; 271 272 _count = min3(count, len, PAGE_SIZE); 273 nr_read = access_remote_vm(mm, p, page, _count, 0); 274 if (nr_read < 0) 275 rv = nr_read; 276 if (nr_read <= 0) 277 goto out_free_page; 278 279 if (copy_to_user(buf, page, nr_read)) { 280 rv = -EFAULT; 281 goto out_free_page; 282 } 283 284 p += nr_read; 285 len -= nr_read; 286 buf += nr_read; 287 count -= nr_read; 288 rv += nr_read; 289 } 290 } else { 291 /* 292 * Command line (1 string) occupies ARGV and maybe 293 * extends into ENVP. 294 */ 295 if (len1 + len2 <= *pos) 296 goto skip_argv_envp; 297 if (len1 <= *pos) 298 goto skip_argv; 299 300 p = arg_start + *pos; 301 len = len1 - *pos; 302 while (count > 0 && len > 0) { 303 unsigned int _count, l; 304 int nr_read; 305 bool final; 306 307 _count = min3(count, len, PAGE_SIZE); 308 nr_read = access_remote_vm(mm, p, page, _count, 0); 309 if (nr_read < 0) 310 rv = nr_read; 311 if (nr_read <= 0) 312 goto out_free_page; 313 314 /* 315 * Command line can be shorter than whole ARGV 316 * even if last "marker" byte says it is not. 317 */ 318 final = false; 319 l = strnlen(page, nr_read); 320 if (l < nr_read) { 321 nr_read = l; 322 final = true; 323 } 324 325 if (copy_to_user(buf, page, nr_read)) { 326 rv = -EFAULT; 327 goto out_free_page; 328 } 329 330 p += nr_read; 331 len -= nr_read; 332 buf += nr_read; 333 count -= nr_read; 334 rv += nr_read; 335 336 if (final) 337 goto out_free_page; 338 } 339 skip_argv: 340 /* 341 * Command line (1 string) occupies ARGV and 342 * extends into ENVP. 343 */ 344 if (len1 <= *pos) { 345 p = env_start + *pos - len1; 346 len = len1 + len2 - *pos; 347 } else { 348 p = env_start; 349 len = len2; 350 } 351 while (count > 0 && len > 0) { 352 unsigned int _count, l; 353 int nr_read; 354 bool final; 355 356 _count = min3(count, len, PAGE_SIZE); 357 nr_read = access_remote_vm(mm, p, page, _count, 0); 358 if (nr_read < 0) 359 rv = nr_read; 360 if (nr_read <= 0) 361 goto out_free_page; 362 363 /* Find EOS. */ 364 final = false; 365 l = strnlen(page, nr_read); 366 if (l < nr_read) { 367 nr_read = l; 368 final = true; 369 } 370 371 if (copy_to_user(buf, page, nr_read)) { 372 rv = -EFAULT; 373 goto out_free_page; 374 } 375 376 p += nr_read; 377 len -= nr_read; 378 buf += nr_read; 379 count -= nr_read; 380 rv += nr_read; 381 382 if (final) 383 goto out_free_page; 384 } 385 skip_argv_envp: 386 ; 387 } 388 389 out_free_page: 390 free_page((unsigned long)page); 391 out_mmput: 392 mmput(mm); 393 if (rv > 0) 394 *pos += rv; 395 return rv; 396 } 397 398 static const struct file_operations proc_pid_cmdline_ops = { 399 .read = proc_pid_cmdline_read, 400 .llseek = generic_file_llseek, 401 }; 402 403 static int proc_pid_auxv(struct seq_file *m, struct pid_namespace *ns, 404 struct pid *pid, struct task_struct *task) 405 { 406 struct mm_struct *mm = mm_access(task, PTRACE_MODE_READ); 407 if (mm && !IS_ERR(mm)) { 408 unsigned int nwords = 0; 409 do { 410 nwords += 2; 411 } while (mm->saved_auxv[nwords - 2] != 0); /* AT_NULL */ 412 seq_write(m, mm->saved_auxv, nwords * sizeof(mm->saved_auxv[0])); 413 mmput(mm); 414 return 0; 415 } else 416 return PTR_ERR(mm); 417 } 418 419 420 #ifdef CONFIG_KALLSYMS 421 /* 422 * Provides a wchan file via kallsyms in a proper one-value-per-file format. 423 * Returns the resolved symbol. If that fails, simply return the address. 424 */ 425 static int proc_pid_wchan(struct seq_file *m, struct pid_namespace *ns, 426 struct pid *pid, struct task_struct *task) 427 { 428 unsigned long wchan; 429 char symname[KSYM_NAME_LEN]; 430 431 wchan = get_wchan(task); 432 433 if (lookup_symbol_name(wchan, symname) < 0) { 434 if (!ptrace_may_access(task, PTRACE_MODE_READ)) 435 return 0; 436 seq_printf(m, "%lu", wchan); 437 } else { 438 seq_printf(m, "%s", symname); 439 } 440 441 return 0; 442 } 443 #endif /* CONFIG_KALLSYMS */ 444 445 static int lock_trace(struct task_struct *task) 446 { 447 int err = mutex_lock_killable(&task->signal->cred_guard_mutex); 448 if (err) 449 return err; 450 if (!ptrace_may_access(task, PTRACE_MODE_ATTACH)) { 451 mutex_unlock(&task->signal->cred_guard_mutex); 452 return -EPERM; 453 } 454 return 0; 455 } 456 457 static void unlock_trace(struct task_struct *task) 458 { 459 mutex_unlock(&task->signal->cred_guard_mutex); 460 } 461 462 #ifdef CONFIG_STACKTRACE 463 464 #define MAX_STACK_TRACE_DEPTH 64 465 466 static int proc_pid_stack(struct seq_file *m, struct pid_namespace *ns, 467 struct pid *pid, struct task_struct *task) 468 { 469 struct stack_trace trace; 470 unsigned long *entries; 471 int err; 472 int i; 473 474 entries = kmalloc(MAX_STACK_TRACE_DEPTH * sizeof(*entries), GFP_KERNEL); 475 if (!entries) 476 return -ENOMEM; 477 478 trace.nr_entries = 0; 479 trace.max_entries = MAX_STACK_TRACE_DEPTH; 480 trace.entries = entries; 481 trace.skip = 0; 482 483 err = lock_trace(task); 484 if (!err) { 485 save_stack_trace_tsk(task, &trace); 486 487 for (i = 0; i < trace.nr_entries; i++) { 488 seq_printf(m, "[<%pK>] %pS\n", 489 (void *)entries[i], (void *)entries[i]); 490 } 491 unlock_trace(task); 492 } 493 kfree(entries); 494 495 return err; 496 } 497 #endif 498 499 #ifdef CONFIG_SCHED_INFO 500 /* 501 * Provides /proc/PID/schedstat 502 */ 503 static int proc_pid_schedstat(struct seq_file *m, struct pid_namespace *ns, 504 struct pid *pid, struct task_struct *task) 505 { 506 if (unlikely(!sched_info_on())) 507 seq_printf(m, "0 0 0\n"); 508 else 509 seq_printf(m, "%llu %llu %lu\n", 510 (unsigned long long)task->se.sum_exec_runtime, 511 (unsigned long long)task->sched_info.run_delay, 512 task->sched_info.pcount); 513 514 return 0; 515 } 516 #endif 517 518 #ifdef CONFIG_LATENCYTOP 519 static int lstats_show_proc(struct seq_file *m, void *v) 520 { 521 int i; 522 struct inode *inode = m->private; 523 struct task_struct *task = get_proc_task(inode); 524 525 if (!task) 526 return -ESRCH; 527 seq_puts(m, "Latency Top version : v0.1\n"); 528 for (i = 0; i < 32; i++) { 529 struct latency_record *lr = &task->latency_record[i]; 530 if (lr->backtrace[0]) { 531 int q; 532 seq_printf(m, "%i %li %li", 533 lr->count, lr->time, lr->max); 534 for (q = 0; q < LT_BACKTRACEDEPTH; q++) { 535 unsigned long bt = lr->backtrace[q]; 536 if (!bt) 537 break; 538 if (bt == ULONG_MAX) 539 break; 540 seq_printf(m, " %ps", (void *)bt); 541 } 542 seq_putc(m, '\n'); 543 } 544 545 } 546 put_task_struct(task); 547 return 0; 548 } 549 550 static int lstats_open(struct inode *inode, struct file *file) 551 { 552 return single_open(file, lstats_show_proc, inode); 553 } 554 555 static ssize_t lstats_write(struct file *file, const char __user *buf, 556 size_t count, loff_t *offs) 557 { 558 struct task_struct *task = get_proc_task(file_inode(file)); 559 560 if (!task) 561 return -ESRCH; 562 clear_all_latency_tracing(task); 563 put_task_struct(task); 564 565 return count; 566 } 567 568 static const struct file_operations proc_lstats_operations = { 569 .open = lstats_open, 570 .read = seq_read, 571 .write = lstats_write, 572 .llseek = seq_lseek, 573 .release = single_release, 574 }; 575 576 #endif 577 578 static int proc_oom_score(struct seq_file *m, struct pid_namespace *ns, 579 struct pid *pid, struct task_struct *task) 580 { 581 unsigned long totalpages = totalram_pages + total_swap_pages; 582 unsigned long points = 0; 583 584 read_lock(&tasklist_lock); 585 if (pid_alive(task)) 586 points = oom_badness(task, NULL, NULL, totalpages) * 587 1000 / totalpages; 588 read_unlock(&tasklist_lock); 589 seq_printf(m, "%lu\n", points); 590 591 return 0; 592 } 593 594 struct limit_names { 595 const char *name; 596 const char *unit; 597 }; 598 599 static const struct limit_names lnames[RLIM_NLIMITS] = { 600 [RLIMIT_CPU] = {"Max cpu time", "seconds"}, 601 [RLIMIT_FSIZE] = {"Max file size", "bytes"}, 602 [RLIMIT_DATA] = {"Max data size", "bytes"}, 603 [RLIMIT_STACK] = {"Max stack size", "bytes"}, 604 [RLIMIT_CORE] = {"Max core file size", "bytes"}, 605 [RLIMIT_RSS] = {"Max resident set", "bytes"}, 606 [RLIMIT_NPROC] = {"Max processes", "processes"}, 607 [RLIMIT_NOFILE] = {"Max open files", "files"}, 608 [RLIMIT_MEMLOCK] = {"Max locked memory", "bytes"}, 609 [RLIMIT_AS] = {"Max address space", "bytes"}, 610 [RLIMIT_LOCKS] = {"Max file locks", "locks"}, 611 [RLIMIT_SIGPENDING] = {"Max pending signals", "signals"}, 612 [RLIMIT_MSGQUEUE] = {"Max msgqueue size", "bytes"}, 613 [RLIMIT_NICE] = {"Max nice priority", NULL}, 614 [RLIMIT_RTPRIO] = {"Max realtime priority", NULL}, 615 [RLIMIT_RTTIME] = {"Max realtime timeout", "us"}, 616 }; 617 618 /* Display limits for a process */ 619 static int proc_pid_limits(struct seq_file *m, struct pid_namespace *ns, 620 struct pid *pid, struct task_struct *task) 621 { 622 unsigned int i; 623 unsigned long flags; 624 625 struct rlimit rlim[RLIM_NLIMITS]; 626 627 if (!lock_task_sighand(task, &flags)) 628 return 0; 629 memcpy(rlim, task->signal->rlim, sizeof(struct rlimit) * RLIM_NLIMITS); 630 unlock_task_sighand(task, &flags); 631 632 /* 633 * print the file header 634 */ 635 seq_printf(m, "%-25s %-20s %-20s %-10s\n", 636 "Limit", "Soft Limit", "Hard Limit", "Units"); 637 638 for (i = 0; i < RLIM_NLIMITS; i++) { 639 if (rlim[i].rlim_cur == RLIM_INFINITY) 640 seq_printf(m, "%-25s %-20s ", 641 lnames[i].name, "unlimited"); 642 else 643 seq_printf(m, "%-25s %-20lu ", 644 lnames[i].name, rlim[i].rlim_cur); 645 646 if (rlim[i].rlim_max == RLIM_INFINITY) 647 seq_printf(m, "%-20s ", "unlimited"); 648 else 649 seq_printf(m, "%-20lu ", rlim[i].rlim_max); 650 651 if (lnames[i].unit) 652 seq_printf(m, "%-10s\n", lnames[i].unit); 653 else 654 seq_putc(m, '\n'); 655 } 656 657 return 0; 658 } 659 660 #ifdef CONFIG_HAVE_ARCH_TRACEHOOK 661 static int proc_pid_syscall(struct seq_file *m, struct pid_namespace *ns, 662 struct pid *pid, struct task_struct *task) 663 { 664 long nr; 665 unsigned long args[6], sp, pc; 666 int res; 667 668 res = lock_trace(task); 669 if (res) 670 return res; 671 672 if (task_current_syscall(task, &nr, args, 6, &sp, &pc)) 673 seq_puts(m, "running\n"); 674 else if (nr < 0) 675 seq_printf(m, "%ld 0x%lx 0x%lx\n", nr, sp, pc); 676 else 677 seq_printf(m, 678 "%ld 0x%lx 0x%lx 0x%lx 0x%lx 0x%lx 0x%lx 0x%lx 0x%lx\n", 679 nr, 680 args[0], args[1], args[2], args[3], args[4], args[5], 681 sp, pc); 682 unlock_trace(task); 683 684 return 0; 685 } 686 #endif /* CONFIG_HAVE_ARCH_TRACEHOOK */ 687 688 /************************************************************************/ 689 /* Here the fs part begins */ 690 /************************************************************************/ 691 692 /* permission checks */ 693 static int proc_fd_access_allowed(struct inode *inode) 694 { 695 struct task_struct *task; 696 int allowed = 0; 697 /* Allow access to a task's file descriptors if it is us or we 698 * may use ptrace attach to the process and find out that 699 * information. 700 */ 701 task = get_proc_task(inode); 702 if (task) { 703 allowed = ptrace_may_access(task, PTRACE_MODE_READ); 704 put_task_struct(task); 705 } 706 return allowed; 707 } 708 709 int proc_setattr(struct dentry *dentry, struct iattr *attr) 710 { 711 int error; 712 struct inode *inode = d_inode(dentry); 713 714 if (attr->ia_valid & ATTR_MODE) 715 return -EPERM; 716 717 error = inode_change_ok(inode, attr); 718 if (error) 719 return error; 720 721 setattr_copy(inode, attr); 722 mark_inode_dirty(inode); 723 return 0; 724 } 725 726 /* 727 * May current process learn task's sched/cmdline info (for hide_pid_min=1) 728 * or euid/egid (for hide_pid_min=2)? 729 */ 730 static bool has_pid_permissions(struct pid_namespace *pid, 731 struct task_struct *task, 732 int hide_pid_min) 733 { 734 if (pid->hide_pid < hide_pid_min) 735 return true; 736 if (in_group_p(pid->pid_gid)) 737 return true; 738 return ptrace_may_access(task, PTRACE_MODE_READ); 739 } 740 741 742 static int proc_pid_permission(struct inode *inode, int mask) 743 { 744 struct pid_namespace *pid = inode->i_sb->s_fs_info; 745 struct task_struct *task; 746 bool has_perms; 747 748 task = get_proc_task(inode); 749 if (!task) 750 return -ESRCH; 751 has_perms = has_pid_permissions(pid, task, 1); 752 put_task_struct(task); 753 754 if (!has_perms) { 755 if (pid->hide_pid == 2) { 756 /* 757 * Let's make getdents(), stat(), and open() 758 * consistent with each other. If a process 759 * may not stat() a file, it shouldn't be seen 760 * in procfs at all. 761 */ 762 return -ENOENT; 763 } 764 765 return -EPERM; 766 } 767 return generic_permission(inode, mask); 768 } 769 770 771 772 static const struct inode_operations proc_def_inode_operations = { 773 .setattr = proc_setattr, 774 }; 775 776 static int proc_single_show(struct seq_file *m, void *v) 777 { 778 struct inode *inode = m->private; 779 struct pid_namespace *ns; 780 struct pid *pid; 781 struct task_struct *task; 782 int ret; 783 784 ns = inode->i_sb->s_fs_info; 785 pid = proc_pid(inode); 786 task = get_pid_task(pid, PIDTYPE_PID); 787 if (!task) 788 return -ESRCH; 789 790 ret = PROC_I(inode)->op.proc_show(m, ns, pid, task); 791 792 put_task_struct(task); 793 return ret; 794 } 795 796 static int proc_single_open(struct inode *inode, struct file *filp) 797 { 798 return single_open(filp, proc_single_show, inode); 799 } 800 801 static const struct file_operations proc_single_file_operations = { 802 .open = proc_single_open, 803 .read = seq_read, 804 .llseek = seq_lseek, 805 .release = single_release, 806 }; 807 808 809 struct mm_struct *proc_mem_open(struct inode *inode, unsigned int mode) 810 { 811 struct task_struct *task = get_proc_task(inode); 812 struct mm_struct *mm = ERR_PTR(-ESRCH); 813 814 if (task) { 815 mm = mm_access(task, mode); 816 put_task_struct(task); 817 818 if (!IS_ERR_OR_NULL(mm)) { 819 /* ensure this mm_struct can't be freed */ 820 atomic_inc(&mm->mm_count); 821 /* but do not pin its memory */ 822 mmput(mm); 823 } 824 } 825 826 return mm; 827 } 828 829 static int __mem_open(struct inode *inode, struct file *file, unsigned int mode) 830 { 831 struct mm_struct *mm = proc_mem_open(inode, mode); 832 833 if (IS_ERR(mm)) 834 return PTR_ERR(mm); 835 836 file->private_data = mm; 837 return 0; 838 } 839 840 static int mem_open(struct inode *inode, struct file *file) 841 { 842 int ret = __mem_open(inode, file, PTRACE_MODE_ATTACH); 843 844 /* OK to pass negative loff_t, we can catch out-of-range */ 845 file->f_mode |= FMODE_UNSIGNED_OFFSET; 846 847 return ret; 848 } 849 850 static ssize_t mem_rw(struct file *file, char __user *buf, 851 size_t count, loff_t *ppos, int write) 852 { 853 struct mm_struct *mm = file->private_data; 854 unsigned long addr = *ppos; 855 ssize_t copied; 856 char *page; 857 858 if (!mm) 859 return 0; 860 861 page = (char *)__get_free_page(GFP_TEMPORARY); 862 if (!page) 863 return -ENOMEM; 864 865 copied = 0; 866 if (!atomic_inc_not_zero(&mm->mm_users)) 867 goto free; 868 869 while (count > 0) { 870 int this_len = min_t(int, count, PAGE_SIZE); 871 872 if (write && copy_from_user(page, buf, this_len)) { 873 copied = -EFAULT; 874 break; 875 } 876 877 this_len = access_remote_vm(mm, addr, page, this_len, write); 878 if (!this_len) { 879 if (!copied) 880 copied = -EIO; 881 break; 882 } 883 884 if (!write && copy_to_user(buf, page, this_len)) { 885 copied = -EFAULT; 886 break; 887 } 888 889 buf += this_len; 890 addr += this_len; 891 copied += this_len; 892 count -= this_len; 893 } 894 *ppos = addr; 895 896 mmput(mm); 897 free: 898 free_page((unsigned long) page); 899 return copied; 900 } 901 902 static ssize_t mem_read(struct file *file, char __user *buf, 903 size_t count, loff_t *ppos) 904 { 905 return mem_rw(file, buf, count, ppos, 0); 906 } 907 908 static ssize_t mem_write(struct file *file, const char __user *buf, 909 size_t count, loff_t *ppos) 910 { 911 return mem_rw(file, (char __user*)buf, count, ppos, 1); 912 } 913 914 loff_t mem_lseek(struct file *file, loff_t offset, int orig) 915 { 916 switch (orig) { 917 case 0: 918 file->f_pos = offset; 919 break; 920 case 1: 921 file->f_pos += offset; 922 break; 923 default: 924 return -EINVAL; 925 } 926 force_successful_syscall_return(); 927 return file->f_pos; 928 } 929 930 static int mem_release(struct inode *inode, struct file *file) 931 { 932 struct mm_struct *mm = file->private_data; 933 if (mm) 934 mmdrop(mm); 935 return 0; 936 } 937 938 static const struct file_operations proc_mem_operations = { 939 .llseek = mem_lseek, 940 .read = mem_read, 941 .write = mem_write, 942 .open = mem_open, 943 .release = mem_release, 944 }; 945 946 static int environ_open(struct inode *inode, struct file *file) 947 { 948 return __mem_open(inode, file, PTRACE_MODE_READ); 949 } 950 951 static ssize_t environ_read(struct file *file, char __user *buf, 952 size_t count, loff_t *ppos) 953 { 954 char *page; 955 unsigned long src = *ppos; 956 int ret = 0; 957 struct mm_struct *mm = file->private_data; 958 959 if (!mm) 960 return 0; 961 962 page = (char *)__get_free_page(GFP_TEMPORARY); 963 if (!page) 964 return -ENOMEM; 965 966 ret = 0; 967 if (!atomic_inc_not_zero(&mm->mm_users)) 968 goto free; 969 while (count > 0) { 970 size_t this_len, max_len; 971 int retval; 972 973 if (src >= (mm->env_end - mm->env_start)) 974 break; 975 976 this_len = mm->env_end - (mm->env_start + src); 977 978 max_len = min_t(size_t, PAGE_SIZE, count); 979 this_len = min(max_len, this_len); 980 981 retval = access_remote_vm(mm, (mm->env_start + src), 982 page, this_len, 0); 983 984 if (retval <= 0) { 985 ret = retval; 986 break; 987 } 988 989 if (copy_to_user(buf, page, retval)) { 990 ret = -EFAULT; 991 break; 992 } 993 994 ret += retval; 995 src += retval; 996 buf += retval; 997 count -= retval; 998 } 999 *ppos = src; 1000 mmput(mm); 1001 1002 free: 1003 free_page((unsigned long) page); 1004 return ret; 1005 } 1006 1007 static const struct file_operations proc_environ_operations = { 1008 .open = environ_open, 1009 .read = environ_read, 1010 .llseek = generic_file_llseek, 1011 .release = mem_release, 1012 }; 1013 1014 static ssize_t oom_adj_read(struct file *file, char __user *buf, size_t count, 1015 loff_t *ppos) 1016 { 1017 struct task_struct *task = get_proc_task(file_inode(file)); 1018 char buffer[PROC_NUMBUF]; 1019 int oom_adj = OOM_ADJUST_MIN; 1020 size_t len; 1021 unsigned long flags; 1022 1023 if (!task) 1024 return -ESRCH; 1025 if (lock_task_sighand(task, &flags)) { 1026 if (task->signal->oom_score_adj == OOM_SCORE_ADJ_MAX) 1027 oom_adj = OOM_ADJUST_MAX; 1028 else 1029 oom_adj = (task->signal->oom_score_adj * -OOM_DISABLE) / 1030 OOM_SCORE_ADJ_MAX; 1031 unlock_task_sighand(task, &flags); 1032 } 1033 put_task_struct(task); 1034 len = snprintf(buffer, sizeof(buffer), "%d\n", oom_adj); 1035 return simple_read_from_buffer(buf, count, ppos, buffer, len); 1036 } 1037 1038 static ssize_t oom_adj_write(struct file *file, const char __user *buf, 1039 size_t count, loff_t *ppos) 1040 { 1041 struct task_struct *task; 1042 char buffer[PROC_NUMBUF]; 1043 int oom_adj; 1044 unsigned long flags; 1045 int err; 1046 1047 memset(buffer, 0, sizeof(buffer)); 1048 if (count > sizeof(buffer) - 1) 1049 count = sizeof(buffer) - 1; 1050 if (copy_from_user(buffer, buf, count)) { 1051 err = -EFAULT; 1052 goto out; 1053 } 1054 1055 err = kstrtoint(strstrip(buffer), 0, &oom_adj); 1056 if (err) 1057 goto out; 1058 if ((oom_adj < OOM_ADJUST_MIN || oom_adj > OOM_ADJUST_MAX) && 1059 oom_adj != OOM_DISABLE) { 1060 err = -EINVAL; 1061 goto out; 1062 } 1063 1064 task = get_proc_task(file_inode(file)); 1065 if (!task) { 1066 err = -ESRCH; 1067 goto out; 1068 } 1069 1070 task_lock(task); 1071 if (!task->mm) { 1072 err = -EINVAL; 1073 goto err_task_lock; 1074 } 1075 1076 if (!lock_task_sighand(task, &flags)) { 1077 err = -ESRCH; 1078 goto err_task_lock; 1079 } 1080 1081 /* 1082 * Scale /proc/pid/oom_score_adj appropriately ensuring that a maximum 1083 * value is always attainable. 1084 */ 1085 if (oom_adj == OOM_ADJUST_MAX) 1086 oom_adj = OOM_SCORE_ADJ_MAX; 1087 else 1088 oom_adj = (oom_adj * OOM_SCORE_ADJ_MAX) / -OOM_DISABLE; 1089 1090 if (oom_adj < task->signal->oom_score_adj && 1091 !capable(CAP_SYS_RESOURCE)) { 1092 err = -EACCES; 1093 goto err_sighand; 1094 } 1095 1096 /* 1097 * /proc/pid/oom_adj is provided for legacy purposes, ask users to use 1098 * /proc/pid/oom_score_adj instead. 1099 */ 1100 pr_warn_once("%s (%d): /proc/%d/oom_adj is deprecated, please use /proc/%d/oom_score_adj instead.\n", 1101 current->comm, task_pid_nr(current), task_pid_nr(task), 1102 task_pid_nr(task)); 1103 1104 task->signal->oom_score_adj = oom_adj; 1105 trace_oom_score_adj_update(task); 1106 err_sighand: 1107 unlock_task_sighand(task, &flags); 1108 err_task_lock: 1109 task_unlock(task); 1110 put_task_struct(task); 1111 out: 1112 return err < 0 ? err : count; 1113 } 1114 1115 static const struct file_operations proc_oom_adj_operations = { 1116 .read = oom_adj_read, 1117 .write = oom_adj_write, 1118 .llseek = generic_file_llseek, 1119 }; 1120 1121 static ssize_t oom_score_adj_read(struct file *file, char __user *buf, 1122 size_t count, loff_t *ppos) 1123 { 1124 struct task_struct *task = get_proc_task(file_inode(file)); 1125 char buffer[PROC_NUMBUF]; 1126 short oom_score_adj = OOM_SCORE_ADJ_MIN; 1127 unsigned long flags; 1128 size_t len; 1129 1130 if (!task) 1131 return -ESRCH; 1132 if (lock_task_sighand(task, &flags)) { 1133 oom_score_adj = task->signal->oom_score_adj; 1134 unlock_task_sighand(task, &flags); 1135 } 1136 put_task_struct(task); 1137 len = snprintf(buffer, sizeof(buffer), "%hd\n", oom_score_adj); 1138 return simple_read_from_buffer(buf, count, ppos, buffer, len); 1139 } 1140 1141 static ssize_t oom_score_adj_write(struct file *file, const char __user *buf, 1142 size_t count, loff_t *ppos) 1143 { 1144 struct task_struct *task; 1145 char buffer[PROC_NUMBUF]; 1146 unsigned long flags; 1147 int oom_score_adj; 1148 int err; 1149 1150 memset(buffer, 0, sizeof(buffer)); 1151 if (count > sizeof(buffer) - 1) 1152 count = sizeof(buffer) - 1; 1153 if (copy_from_user(buffer, buf, count)) { 1154 err = -EFAULT; 1155 goto out; 1156 } 1157 1158 err = kstrtoint(strstrip(buffer), 0, &oom_score_adj); 1159 if (err) 1160 goto out; 1161 if (oom_score_adj < OOM_SCORE_ADJ_MIN || 1162 oom_score_adj > OOM_SCORE_ADJ_MAX) { 1163 err = -EINVAL; 1164 goto out; 1165 } 1166 1167 task = get_proc_task(file_inode(file)); 1168 if (!task) { 1169 err = -ESRCH; 1170 goto out; 1171 } 1172 1173 task_lock(task); 1174 if (!task->mm) { 1175 err = -EINVAL; 1176 goto err_task_lock; 1177 } 1178 1179 if (!lock_task_sighand(task, &flags)) { 1180 err = -ESRCH; 1181 goto err_task_lock; 1182 } 1183 1184 if ((short)oom_score_adj < task->signal->oom_score_adj_min && 1185 !capable(CAP_SYS_RESOURCE)) { 1186 err = -EACCES; 1187 goto err_sighand; 1188 } 1189 1190 task->signal->oom_score_adj = (short)oom_score_adj; 1191 if (has_capability_noaudit(current, CAP_SYS_RESOURCE)) 1192 task->signal->oom_score_adj_min = (short)oom_score_adj; 1193 trace_oom_score_adj_update(task); 1194 1195 err_sighand: 1196 unlock_task_sighand(task, &flags); 1197 err_task_lock: 1198 task_unlock(task); 1199 put_task_struct(task); 1200 out: 1201 return err < 0 ? err : count; 1202 } 1203 1204 static const struct file_operations proc_oom_score_adj_operations = { 1205 .read = oom_score_adj_read, 1206 .write = oom_score_adj_write, 1207 .llseek = default_llseek, 1208 }; 1209 1210 #ifdef CONFIG_AUDITSYSCALL 1211 #define TMPBUFLEN 21 1212 static ssize_t proc_loginuid_read(struct file * file, char __user * buf, 1213 size_t count, loff_t *ppos) 1214 { 1215 struct inode * inode = file_inode(file); 1216 struct task_struct *task = get_proc_task(inode); 1217 ssize_t length; 1218 char tmpbuf[TMPBUFLEN]; 1219 1220 if (!task) 1221 return -ESRCH; 1222 length = scnprintf(tmpbuf, TMPBUFLEN, "%u", 1223 from_kuid(file->f_cred->user_ns, 1224 audit_get_loginuid(task))); 1225 put_task_struct(task); 1226 return simple_read_from_buffer(buf, count, ppos, tmpbuf, length); 1227 } 1228 1229 static ssize_t proc_loginuid_write(struct file * file, const char __user * buf, 1230 size_t count, loff_t *ppos) 1231 { 1232 struct inode * inode = file_inode(file); 1233 char *page, *tmp; 1234 ssize_t length; 1235 uid_t loginuid; 1236 kuid_t kloginuid; 1237 1238 rcu_read_lock(); 1239 if (current != pid_task(proc_pid(inode), PIDTYPE_PID)) { 1240 rcu_read_unlock(); 1241 return -EPERM; 1242 } 1243 rcu_read_unlock(); 1244 1245 if (count >= PAGE_SIZE) 1246 count = PAGE_SIZE - 1; 1247 1248 if (*ppos != 0) { 1249 /* No partial writes. */ 1250 return -EINVAL; 1251 } 1252 page = (char*)__get_free_page(GFP_TEMPORARY); 1253 if (!page) 1254 return -ENOMEM; 1255 length = -EFAULT; 1256 if (copy_from_user(page, buf, count)) 1257 goto out_free_page; 1258 1259 page[count] = '\0'; 1260 loginuid = simple_strtoul(page, &tmp, 10); 1261 if (tmp == page) { 1262 length = -EINVAL; 1263 goto out_free_page; 1264 1265 } 1266 1267 /* is userspace tring to explicitly UNSET the loginuid? */ 1268 if (loginuid == AUDIT_UID_UNSET) { 1269 kloginuid = INVALID_UID; 1270 } else { 1271 kloginuid = make_kuid(file->f_cred->user_ns, loginuid); 1272 if (!uid_valid(kloginuid)) { 1273 length = -EINVAL; 1274 goto out_free_page; 1275 } 1276 } 1277 1278 length = audit_set_loginuid(kloginuid); 1279 if (likely(length == 0)) 1280 length = count; 1281 1282 out_free_page: 1283 free_page((unsigned long) page); 1284 return length; 1285 } 1286 1287 static const struct file_operations proc_loginuid_operations = { 1288 .read = proc_loginuid_read, 1289 .write = proc_loginuid_write, 1290 .llseek = generic_file_llseek, 1291 }; 1292 1293 static ssize_t proc_sessionid_read(struct file * file, char __user * buf, 1294 size_t count, loff_t *ppos) 1295 { 1296 struct inode * inode = file_inode(file); 1297 struct task_struct *task = get_proc_task(inode); 1298 ssize_t length; 1299 char tmpbuf[TMPBUFLEN]; 1300 1301 if (!task) 1302 return -ESRCH; 1303 length = scnprintf(tmpbuf, TMPBUFLEN, "%u", 1304 audit_get_sessionid(task)); 1305 put_task_struct(task); 1306 return simple_read_from_buffer(buf, count, ppos, tmpbuf, length); 1307 } 1308 1309 static const struct file_operations proc_sessionid_operations = { 1310 .read = proc_sessionid_read, 1311 .llseek = generic_file_llseek, 1312 }; 1313 #endif 1314 1315 #ifdef CONFIG_FAULT_INJECTION 1316 static ssize_t proc_fault_inject_read(struct file * file, char __user * buf, 1317 size_t count, loff_t *ppos) 1318 { 1319 struct task_struct *task = get_proc_task(file_inode(file)); 1320 char buffer[PROC_NUMBUF]; 1321 size_t len; 1322 int make_it_fail; 1323 1324 if (!task) 1325 return -ESRCH; 1326 make_it_fail = task->make_it_fail; 1327 put_task_struct(task); 1328 1329 len = snprintf(buffer, sizeof(buffer), "%i\n", make_it_fail); 1330 1331 return simple_read_from_buffer(buf, count, ppos, buffer, len); 1332 } 1333 1334 static ssize_t proc_fault_inject_write(struct file * file, 1335 const char __user * buf, size_t count, loff_t *ppos) 1336 { 1337 struct task_struct *task; 1338 char buffer[PROC_NUMBUF], *end; 1339 int make_it_fail; 1340 1341 if (!capable(CAP_SYS_RESOURCE)) 1342 return -EPERM; 1343 memset(buffer, 0, sizeof(buffer)); 1344 if (count > sizeof(buffer) - 1) 1345 count = sizeof(buffer) - 1; 1346 if (copy_from_user(buffer, buf, count)) 1347 return -EFAULT; 1348 make_it_fail = simple_strtol(strstrip(buffer), &end, 0); 1349 if (*end) 1350 return -EINVAL; 1351 if (make_it_fail < 0 || make_it_fail > 1) 1352 return -EINVAL; 1353 1354 task = get_proc_task(file_inode(file)); 1355 if (!task) 1356 return -ESRCH; 1357 task->make_it_fail = make_it_fail; 1358 put_task_struct(task); 1359 1360 return count; 1361 } 1362 1363 static const struct file_operations proc_fault_inject_operations = { 1364 .read = proc_fault_inject_read, 1365 .write = proc_fault_inject_write, 1366 .llseek = generic_file_llseek, 1367 }; 1368 #endif 1369 1370 1371 #ifdef CONFIG_SCHED_DEBUG 1372 /* 1373 * Print out various scheduling related per-task fields: 1374 */ 1375 static int sched_show(struct seq_file *m, void *v) 1376 { 1377 struct inode *inode = m->private; 1378 struct task_struct *p; 1379 1380 p = get_proc_task(inode); 1381 if (!p) 1382 return -ESRCH; 1383 proc_sched_show_task(p, m); 1384 1385 put_task_struct(p); 1386 1387 return 0; 1388 } 1389 1390 static ssize_t 1391 sched_write(struct file *file, const char __user *buf, 1392 size_t count, loff_t *offset) 1393 { 1394 struct inode *inode = file_inode(file); 1395 struct task_struct *p; 1396 1397 p = get_proc_task(inode); 1398 if (!p) 1399 return -ESRCH; 1400 proc_sched_set_task(p); 1401 1402 put_task_struct(p); 1403 1404 return count; 1405 } 1406 1407 static int sched_open(struct inode *inode, struct file *filp) 1408 { 1409 return single_open(filp, sched_show, inode); 1410 } 1411 1412 static const struct file_operations proc_pid_sched_operations = { 1413 .open = sched_open, 1414 .read = seq_read, 1415 .write = sched_write, 1416 .llseek = seq_lseek, 1417 .release = single_release, 1418 }; 1419 1420 #endif 1421 1422 #ifdef CONFIG_SCHED_AUTOGROUP 1423 /* 1424 * Print out autogroup related information: 1425 */ 1426 static int sched_autogroup_show(struct seq_file *m, void *v) 1427 { 1428 struct inode *inode = m->private; 1429 struct task_struct *p; 1430 1431 p = get_proc_task(inode); 1432 if (!p) 1433 return -ESRCH; 1434 proc_sched_autogroup_show_task(p, m); 1435 1436 put_task_struct(p); 1437 1438 return 0; 1439 } 1440 1441 static ssize_t 1442 sched_autogroup_write(struct file *file, const char __user *buf, 1443 size_t count, loff_t *offset) 1444 { 1445 struct inode *inode = file_inode(file); 1446 struct task_struct *p; 1447 char buffer[PROC_NUMBUF]; 1448 int nice; 1449 int err; 1450 1451 memset(buffer, 0, sizeof(buffer)); 1452 if (count > sizeof(buffer) - 1) 1453 count = sizeof(buffer) - 1; 1454 if (copy_from_user(buffer, buf, count)) 1455 return -EFAULT; 1456 1457 err = kstrtoint(strstrip(buffer), 0, &nice); 1458 if (err < 0) 1459 return err; 1460 1461 p = get_proc_task(inode); 1462 if (!p) 1463 return -ESRCH; 1464 1465 err = proc_sched_autogroup_set_nice(p, nice); 1466 if (err) 1467 count = err; 1468 1469 put_task_struct(p); 1470 1471 return count; 1472 } 1473 1474 static int sched_autogroup_open(struct inode *inode, struct file *filp) 1475 { 1476 int ret; 1477 1478 ret = single_open(filp, sched_autogroup_show, NULL); 1479 if (!ret) { 1480 struct seq_file *m = filp->private_data; 1481 1482 m->private = inode; 1483 } 1484 return ret; 1485 } 1486 1487 static const struct file_operations proc_pid_sched_autogroup_operations = { 1488 .open = sched_autogroup_open, 1489 .read = seq_read, 1490 .write = sched_autogroup_write, 1491 .llseek = seq_lseek, 1492 .release = single_release, 1493 }; 1494 1495 #endif /* CONFIG_SCHED_AUTOGROUP */ 1496 1497 static ssize_t comm_write(struct file *file, const char __user *buf, 1498 size_t count, loff_t *offset) 1499 { 1500 struct inode *inode = file_inode(file); 1501 struct task_struct *p; 1502 char buffer[TASK_COMM_LEN]; 1503 const size_t maxlen = sizeof(buffer) - 1; 1504 1505 memset(buffer, 0, sizeof(buffer)); 1506 if (copy_from_user(buffer, buf, count > maxlen ? maxlen : count)) 1507 return -EFAULT; 1508 1509 p = get_proc_task(inode); 1510 if (!p) 1511 return -ESRCH; 1512 1513 if (same_thread_group(current, p)) 1514 set_task_comm(p, buffer); 1515 else 1516 count = -EINVAL; 1517 1518 put_task_struct(p); 1519 1520 return count; 1521 } 1522 1523 static int comm_show(struct seq_file *m, void *v) 1524 { 1525 struct inode *inode = m->private; 1526 struct task_struct *p; 1527 1528 p = get_proc_task(inode); 1529 if (!p) 1530 return -ESRCH; 1531 1532 task_lock(p); 1533 seq_printf(m, "%s\n", p->comm); 1534 task_unlock(p); 1535 1536 put_task_struct(p); 1537 1538 return 0; 1539 } 1540 1541 static int comm_open(struct inode *inode, struct file *filp) 1542 { 1543 return single_open(filp, comm_show, inode); 1544 } 1545 1546 static const struct file_operations proc_pid_set_comm_operations = { 1547 .open = comm_open, 1548 .read = seq_read, 1549 .write = comm_write, 1550 .llseek = seq_lseek, 1551 .release = single_release, 1552 }; 1553 1554 static int proc_exe_link(struct dentry *dentry, struct path *exe_path) 1555 { 1556 struct task_struct *task; 1557 struct mm_struct *mm; 1558 struct file *exe_file; 1559 1560 task = get_proc_task(d_inode(dentry)); 1561 if (!task) 1562 return -ENOENT; 1563 mm = get_task_mm(task); 1564 put_task_struct(task); 1565 if (!mm) 1566 return -ENOENT; 1567 exe_file = get_mm_exe_file(mm); 1568 mmput(mm); 1569 if (exe_file) { 1570 *exe_path = exe_file->f_path; 1571 path_get(&exe_file->f_path); 1572 fput(exe_file); 1573 return 0; 1574 } else 1575 return -ENOENT; 1576 } 1577 1578 static const char *proc_pid_follow_link(struct dentry *dentry, void **cookie) 1579 { 1580 struct inode *inode = d_inode(dentry); 1581 struct path path; 1582 int error = -EACCES; 1583 1584 /* Are we allowed to snoop on the tasks file descriptors? */ 1585 if (!proc_fd_access_allowed(inode)) 1586 goto out; 1587 1588 error = PROC_I(inode)->op.proc_get_link(dentry, &path); 1589 if (error) 1590 goto out; 1591 1592 nd_jump_link(&path); 1593 return NULL; 1594 out: 1595 return ERR_PTR(error); 1596 } 1597 1598 static int do_proc_readlink(struct path *path, char __user *buffer, int buflen) 1599 { 1600 char *tmp = (char*)__get_free_page(GFP_TEMPORARY); 1601 char *pathname; 1602 int len; 1603 1604 if (!tmp) 1605 return -ENOMEM; 1606 1607 pathname = d_path(path, tmp, PAGE_SIZE); 1608 len = PTR_ERR(pathname); 1609 if (IS_ERR(pathname)) 1610 goto out; 1611 len = tmp + PAGE_SIZE - 1 - pathname; 1612 1613 if (len > buflen) 1614 len = buflen; 1615 if (copy_to_user(buffer, pathname, len)) 1616 len = -EFAULT; 1617 out: 1618 free_page((unsigned long)tmp); 1619 return len; 1620 } 1621 1622 static int proc_pid_readlink(struct dentry * dentry, char __user * buffer, int buflen) 1623 { 1624 int error = -EACCES; 1625 struct inode *inode = d_inode(dentry); 1626 struct path path; 1627 1628 /* Are we allowed to snoop on the tasks file descriptors? */ 1629 if (!proc_fd_access_allowed(inode)) 1630 goto out; 1631 1632 error = PROC_I(inode)->op.proc_get_link(dentry, &path); 1633 if (error) 1634 goto out; 1635 1636 error = do_proc_readlink(&path, buffer, buflen); 1637 path_put(&path); 1638 out: 1639 return error; 1640 } 1641 1642 const struct inode_operations proc_pid_link_inode_operations = { 1643 .readlink = proc_pid_readlink, 1644 .follow_link = proc_pid_follow_link, 1645 .setattr = proc_setattr, 1646 }; 1647 1648 1649 /* building an inode */ 1650 1651 struct inode *proc_pid_make_inode(struct super_block * sb, struct task_struct *task) 1652 { 1653 struct inode * inode; 1654 struct proc_inode *ei; 1655 const struct cred *cred; 1656 1657 /* We need a new inode */ 1658 1659 inode = new_inode(sb); 1660 if (!inode) 1661 goto out; 1662 1663 /* Common stuff */ 1664 ei = PROC_I(inode); 1665 inode->i_ino = get_next_ino(); 1666 inode->i_mtime = inode->i_atime = inode->i_ctime = CURRENT_TIME; 1667 inode->i_op = &proc_def_inode_operations; 1668 1669 /* 1670 * grab the reference to task. 1671 */ 1672 ei->pid = get_task_pid(task, PIDTYPE_PID); 1673 if (!ei->pid) 1674 goto out_unlock; 1675 1676 if (task_dumpable(task)) { 1677 rcu_read_lock(); 1678 cred = __task_cred(task); 1679 inode->i_uid = cred->euid; 1680 inode->i_gid = cred->egid; 1681 rcu_read_unlock(); 1682 } 1683 security_task_to_inode(task, inode); 1684 1685 out: 1686 return inode; 1687 1688 out_unlock: 1689 iput(inode); 1690 return NULL; 1691 } 1692 1693 int pid_getattr(struct vfsmount *mnt, struct dentry *dentry, struct kstat *stat) 1694 { 1695 struct inode *inode = d_inode(dentry); 1696 struct task_struct *task; 1697 const struct cred *cred; 1698 struct pid_namespace *pid = dentry->d_sb->s_fs_info; 1699 1700 generic_fillattr(inode, stat); 1701 1702 rcu_read_lock(); 1703 stat->uid = GLOBAL_ROOT_UID; 1704 stat->gid = GLOBAL_ROOT_GID; 1705 task = pid_task(proc_pid(inode), PIDTYPE_PID); 1706 if (task) { 1707 if (!has_pid_permissions(pid, task, 2)) { 1708 rcu_read_unlock(); 1709 /* 1710 * This doesn't prevent learning whether PID exists, 1711 * it only makes getattr() consistent with readdir(). 1712 */ 1713 return -ENOENT; 1714 } 1715 if ((inode->i_mode == (S_IFDIR|S_IRUGO|S_IXUGO)) || 1716 task_dumpable(task)) { 1717 cred = __task_cred(task); 1718 stat->uid = cred->euid; 1719 stat->gid = cred->egid; 1720 } 1721 } 1722 rcu_read_unlock(); 1723 return 0; 1724 } 1725 1726 /* dentry stuff */ 1727 1728 /* 1729 * Exceptional case: normally we are not allowed to unhash a busy 1730 * directory. In this case, however, we can do it - no aliasing problems 1731 * due to the way we treat inodes. 1732 * 1733 * Rewrite the inode's ownerships here because the owning task may have 1734 * performed a setuid(), etc. 1735 * 1736 * Before the /proc/pid/status file was created the only way to read 1737 * the effective uid of a /process was to stat /proc/pid. Reading 1738 * /proc/pid/status is slow enough that procps and other packages 1739 * kept stating /proc/pid. To keep the rules in /proc simple I have 1740 * made this apply to all per process world readable and executable 1741 * directories. 1742 */ 1743 int pid_revalidate(struct dentry *dentry, unsigned int flags) 1744 { 1745 struct inode *inode; 1746 struct task_struct *task; 1747 const struct cred *cred; 1748 1749 if (flags & LOOKUP_RCU) 1750 return -ECHILD; 1751 1752 inode = d_inode(dentry); 1753 task = get_proc_task(inode); 1754 1755 if (task) { 1756 if ((inode->i_mode == (S_IFDIR|S_IRUGO|S_IXUGO)) || 1757 task_dumpable(task)) { 1758 rcu_read_lock(); 1759 cred = __task_cred(task); 1760 inode->i_uid = cred->euid; 1761 inode->i_gid = cred->egid; 1762 rcu_read_unlock(); 1763 } else { 1764 inode->i_uid = GLOBAL_ROOT_UID; 1765 inode->i_gid = GLOBAL_ROOT_GID; 1766 } 1767 inode->i_mode &= ~(S_ISUID | S_ISGID); 1768 security_task_to_inode(task, inode); 1769 put_task_struct(task); 1770 return 1; 1771 } 1772 return 0; 1773 } 1774 1775 static inline bool proc_inode_is_dead(struct inode *inode) 1776 { 1777 return !proc_pid(inode)->tasks[PIDTYPE_PID].first; 1778 } 1779 1780 int pid_delete_dentry(const struct dentry *dentry) 1781 { 1782 /* Is the task we represent dead? 1783 * If so, then don't put the dentry on the lru list, 1784 * kill it immediately. 1785 */ 1786 return proc_inode_is_dead(d_inode(dentry)); 1787 } 1788 1789 const struct dentry_operations pid_dentry_operations = 1790 { 1791 .d_revalidate = pid_revalidate, 1792 .d_delete = pid_delete_dentry, 1793 }; 1794 1795 /* Lookups */ 1796 1797 /* 1798 * Fill a directory entry. 1799 * 1800 * If possible create the dcache entry and derive our inode number and 1801 * file type from dcache entry. 1802 * 1803 * Since all of the proc inode numbers are dynamically generated, the inode 1804 * numbers do not exist until the inode is cache. This means creating the 1805 * the dcache entry in readdir is necessary to keep the inode numbers 1806 * reported by readdir in sync with the inode numbers reported 1807 * by stat. 1808 */ 1809 bool proc_fill_cache(struct file *file, struct dir_context *ctx, 1810 const char *name, int len, 1811 instantiate_t instantiate, struct task_struct *task, const void *ptr) 1812 { 1813 struct dentry *child, *dir = file->f_path.dentry; 1814 struct qstr qname = QSTR_INIT(name, len); 1815 struct inode *inode; 1816 unsigned type; 1817 ino_t ino; 1818 1819 child = d_hash_and_lookup(dir, &qname); 1820 if (!child) { 1821 child = d_alloc(dir, &qname); 1822 if (!child) 1823 goto end_instantiate; 1824 if (instantiate(d_inode(dir), child, task, ptr) < 0) { 1825 dput(child); 1826 goto end_instantiate; 1827 } 1828 } 1829 inode = d_inode(child); 1830 ino = inode->i_ino; 1831 type = inode->i_mode >> 12; 1832 dput(child); 1833 return dir_emit(ctx, name, len, ino, type); 1834 1835 end_instantiate: 1836 return dir_emit(ctx, name, len, 1, DT_UNKNOWN); 1837 } 1838 1839 #ifdef CONFIG_CHECKPOINT_RESTORE 1840 1841 /* 1842 * dname_to_vma_addr - maps a dentry name into two unsigned longs 1843 * which represent vma start and end addresses. 1844 */ 1845 static int dname_to_vma_addr(struct dentry *dentry, 1846 unsigned long *start, unsigned long *end) 1847 { 1848 if (sscanf(dentry->d_name.name, "%lx-%lx", start, end) != 2) 1849 return -EINVAL; 1850 1851 return 0; 1852 } 1853 1854 static int map_files_d_revalidate(struct dentry *dentry, unsigned int flags) 1855 { 1856 unsigned long vm_start, vm_end; 1857 bool exact_vma_exists = false; 1858 struct mm_struct *mm = NULL; 1859 struct task_struct *task; 1860 const struct cred *cred; 1861 struct inode *inode; 1862 int status = 0; 1863 1864 if (flags & LOOKUP_RCU) 1865 return -ECHILD; 1866 1867 if (!capable(CAP_SYS_ADMIN)) { 1868 status = -EPERM; 1869 goto out_notask; 1870 } 1871 1872 inode = d_inode(dentry); 1873 task = get_proc_task(inode); 1874 if (!task) 1875 goto out_notask; 1876 1877 mm = mm_access(task, PTRACE_MODE_READ); 1878 if (IS_ERR_OR_NULL(mm)) 1879 goto out; 1880 1881 if (!dname_to_vma_addr(dentry, &vm_start, &vm_end)) { 1882 down_read(&mm->mmap_sem); 1883 exact_vma_exists = !!find_exact_vma(mm, vm_start, vm_end); 1884 up_read(&mm->mmap_sem); 1885 } 1886 1887 mmput(mm); 1888 1889 if (exact_vma_exists) { 1890 if (task_dumpable(task)) { 1891 rcu_read_lock(); 1892 cred = __task_cred(task); 1893 inode->i_uid = cred->euid; 1894 inode->i_gid = cred->egid; 1895 rcu_read_unlock(); 1896 } else { 1897 inode->i_uid = GLOBAL_ROOT_UID; 1898 inode->i_gid = GLOBAL_ROOT_GID; 1899 } 1900 security_task_to_inode(task, inode); 1901 status = 1; 1902 } 1903 1904 out: 1905 put_task_struct(task); 1906 1907 out_notask: 1908 return status; 1909 } 1910 1911 static const struct dentry_operations tid_map_files_dentry_operations = { 1912 .d_revalidate = map_files_d_revalidate, 1913 .d_delete = pid_delete_dentry, 1914 }; 1915 1916 static int proc_map_files_get_link(struct dentry *dentry, struct path *path) 1917 { 1918 unsigned long vm_start, vm_end; 1919 struct vm_area_struct *vma; 1920 struct task_struct *task; 1921 struct mm_struct *mm; 1922 int rc; 1923 1924 rc = -ENOENT; 1925 task = get_proc_task(d_inode(dentry)); 1926 if (!task) 1927 goto out; 1928 1929 mm = get_task_mm(task); 1930 put_task_struct(task); 1931 if (!mm) 1932 goto out; 1933 1934 rc = dname_to_vma_addr(dentry, &vm_start, &vm_end); 1935 if (rc) 1936 goto out_mmput; 1937 1938 rc = -ENOENT; 1939 down_read(&mm->mmap_sem); 1940 vma = find_exact_vma(mm, vm_start, vm_end); 1941 if (vma && vma->vm_file) { 1942 *path = vma->vm_file->f_path; 1943 path_get(path); 1944 rc = 0; 1945 } 1946 up_read(&mm->mmap_sem); 1947 1948 out_mmput: 1949 mmput(mm); 1950 out: 1951 return rc; 1952 } 1953 1954 struct map_files_info { 1955 fmode_t mode; 1956 unsigned long len; 1957 unsigned char name[4*sizeof(long)+2]; /* max: %lx-%lx\0 */ 1958 }; 1959 1960 static int 1961 proc_map_files_instantiate(struct inode *dir, struct dentry *dentry, 1962 struct task_struct *task, const void *ptr) 1963 { 1964 fmode_t mode = (fmode_t)(unsigned long)ptr; 1965 struct proc_inode *ei; 1966 struct inode *inode; 1967 1968 inode = proc_pid_make_inode(dir->i_sb, task); 1969 if (!inode) 1970 return -ENOENT; 1971 1972 ei = PROC_I(inode); 1973 ei->op.proc_get_link = proc_map_files_get_link; 1974 1975 inode->i_op = &proc_pid_link_inode_operations; 1976 inode->i_size = 64; 1977 inode->i_mode = S_IFLNK; 1978 1979 if (mode & FMODE_READ) 1980 inode->i_mode |= S_IRUSR; 1981 if (mode & FMODE_WRITE) 1982 inode->i_mode |= S_IWUSR; 1983 1984 d_set_d_op(dentry, &tid_map_files_dentry_operations); 1985 d_add(dentry, inode); 1986 1987 return 0; 1988 } 1989 1990 static struct dentry *proc_map_files_lookup(struct inode *dir, 1991 struct dentry *dentry, unsigned int flags) 1992 { 1993 unsigned long vm_start, vm_end; 1994 struct vm_area_struct *vma; 1995 struct task_struct *task; 1996 int result; 1997 struct mm_struct *mm; 1998 1999 result = -EPERM; 2000 if (!capable(CAP_SYS_ADMIN)) 2001 goto out; 2002 2003 result = -ENOENT; 2004 task = get_proc_task(dir); 2005 if (!task) 2006 goto out; 2007 2008 result = -EACCES; 2009 if (!ptrace_may_access(task, PTRACE_MODE_READ)) 2010 goto out_put_task; 2011 2012 result = -ENOENT; 2013 if (dname_to_vma_addr(dentry, &vm_start, &vm_end)) 2014 goto out_put_task; 2015 2016 mm = get_task_mm(task); 2017 if (!mm) 2018 goto out_put_task; 2019 2020 down_read(&mm->mmap_sem); 2021 vma = find_exact_vma(mm, vm_start, vm_end); 2022 if (!vma) 2023 goto out_no_vma; 2024 2025 if (vma->vm_file) 2026 result = proc_map_files_instantiate(dir, dentry, task, 2027 (void *)(unsigned long)vma->vm_file->f_mode); 2028 2029 out_no_vma: 2030 up_read(&mm->mmap_sem); 2031 mmput(mm); 2032 out_put_task: 2033 put_task_struct(task); 2034 out: 2035 return ERR_PTR(result); 2036 } 2037 2038 static const struct inode_operations proc_map_files_inode_operations = { 2039 .lookup = proc_map_files_lookup, 2040 .permission = proc_fd_permission, 2041 .setattr = proc_setattr, 2042 }; 2043 2044 static int 2045 proc_map_files_readdir(struct file *file, struct dir_context *ctx) 2046 { 2047 struct vm_area_struct *vma; 2048 struct task_struct *task; 2049 struct mm_struct *mm; 2050 unsigned long nr_files, pos, i; 2051 struct flex_array *fa = NULL; 2052 struct map_files_info info; 2053 struct map_files_info *p; 2054 int ret; 2055 2056 ret = -EPERM; 2057 if (!capable(CAP_SYS_ADMIN)) 2058 goto out; 2059 2060 ret = -ENOENT; 2061 task = get_proc_task(file_inode(file)); 2062 if (!task) 2063 goto out; 2064 2065 ret = -EACCES; 2066 if (!ptrace_may_access(task, PTRACE_MODE_READ)) 2067 goto out_put_task; 2068 2069 ret = 0; 2070 if (!dir_emit_dots(file, ctx)) 2071 goto out_put_task; 2072 2073 mm = get_task_mm(task); 2074 if (!mm) 2075 goto out_put_task; 2076 down_read(&mm->mmap_sem); 2077 2078 nr_files = 0; 2079 2080 /* 2081 * We need two passes here: 2082 * 2083 * 1) Collect vmas of mapped files with mmap_sem taken 2084 * 2) Release mmap_sem and instantiate entries 2085 * 2086 * otherwise we get lockdep complained, since filldir() 2087 * routine might require mmap_sem taken in might_fault(). 2088 */ 2089 2090 for (vma = mm->mmap, pos = 2; vma; vma = vma->vm_next) { 2091 if (vma->vm_file && ++pos > ctx->pos) 2092 nr_files++; 2093 } 2094 2095 if (nr_files) { 2096 fa = flex_array_alloc(sizeof(info), nr_files, 2097 GFP_KERNEL); 2098 if (!fa || flex_array_prealloc(fa, 0, nr_files, 2099 GFP_KERNEL)) { 2100 ret = -ENOMEM; 2101 if (fa) 2102 flex_array_free(fa); 2103 up_read(&mm->mmap_sem); 2104 mmput(mm); 2105 goto out_put_task; 2106 } 2107 for (i = 0, vma = mm->mmap, pos = 2; vma; 2108 vma = vma->vm_next) { 2109 if (!vma->vm_file) 2110 continue; 2111 if (++pos <= ctx->pos) 2112 continue; 2113 2114 info.mode = vma->vm_file->f_mode; 2115 info.len = snprintf(info.name, 2116 sizeof(info.name), "%lx-%lx", 2117 vma->vm_start, vma->vm_end); 2118 if (flex_array_put(fa, i++, &info, GFP_KERNEL)) 2119 BUG(); 2120 } 2121 } 2122 up_read(&mm->mmap_sem); 2123 2124 for (i = 0; i < nr_files; i++) { 2125 p = flex_array_get(fa, i); 2126 if (!proc_fill_cache(file, ctx, 2127 p->name, p->len, 2128 proc_map_files_instantiate, 2129 task, 2130 (void *)(unsigned long)p->mode)) 2131 break; 2132 ctx->pos++; 2133 } 2134 if (fa) 2135 flex_array_free(fa); 2136 mmput(mm); 2137 2138 out_put_task: 2139 put_task_struct(task); 2140 out: 2141 return ret; 2142 } 2143 2144 static const struct file_operations proc_map_files_operations = { 2145 .read = generic_read_dir, 2146 .iterate = proc_map_files_readdir, 2147 .llseek = default_llseek, 2148 }; 2149 2150 struct timers_private { 2151 struct pid *pid; 2152 struct task_struct *task; 2153 struct sighand_struct *sighand; 2154 struct pid_namespace *ns; 2155 unsigned long flags; 2156 }; 2157 2158 static void *timers_start(struct seq_file *m, loff_t *pos) 2159 { 2160 struct timers_private *tp = m->private; 2161 2162 tp->task = get_pid_task(tp->pid, PIDTYPE_PID); 2163 if (!tp->task) 2164 return ERR_PTR(-ESRCH); 2165 2166 tp->sighand = lock_task_sighand(tp->task, &tp->flags); 2167 if (!tp->sighand) 2168 return ERR_PTR(-ESRCH); 2169 2170 return seq_list_start(&tp->task->signal->posix_timers, *pos); 2171 } 2172 2173 static void *timers_next(struct seq_file *m, void *v, loff_t *pos) 2174 { 2175 struct timers_private *tp = m->private; 2176 return seq_list_next(v, &tp->task->signal->posix_timers, pos); 2177 } 2178 2179 static void timers_stop(struct seq_file *m, void *v) 2180 { 2181 struct timers_private *tp = m->private; 2182 2183 if (tp->sighand) { 2184 unlock_task_sighand(tp->task, &tp->flags); 2185 tp->sighand = NULL; 2186 } 2187 2188 if (tp->task) { 2189 put_task_struct(tp->task); 2190 tp->task = NULL; 2191 } 2192 } 2193 2194 static int show_timer(struct seq_file *m, void *v) 2195 { 2196 struct k_itimer *timer; 2197 struct timers_private *tp = m->private; 2198 int notify; 2199 static const char * const nstr[] = { 2200 [SIGEV_SIGNAL] = "signal", 2201 [SIGEV_NONE] = "none", 2202 [SIGEV_THREAD] = "thread", 2203 }; 2204 2205 timer = list_entry((struct list_head *)v, struct k_itimer, list); 2206 notify = timer->it_sigev_notify; 2207 2208 seq_printf(m, "ID: %d\n", timer->it_id); 2209 seq_printf(m, "signal: %d/%p\n", 2210 timer->sigq->info.si_signo, 2211 timer->sigq->info.si_value.sival_ptr); 2212 seq_printf(m, "notify: %s/%s.%d\n", 2213 nstr[notify & ~SIGEV_THREAD_ID], 2214 (notify & SIGEV_THREAD_ID) ? "tid" : "pid", 2215 pid_nr_ns(timer->it_pid, tp->ns)); 2216 seq_printf(m, "ClockID: %d\n", timer->it_clock); 2217 2218 return 0; 2219 } 2220 2221 static const struct seq_operations proc_timers_seq_ops = { 2222 .start = timers_start, 2223 .next = timers_next, 2224 .stop = timers_stop, 2225 .show = show_timer, 2226 }; 2227 2228 static int proc_timers_open(struct inode *inode, struct file *file) 2229 { 2230 struct timers_private *tp; 2231 2232 tp = __seq_open_private(file, &proc_timers_seq_ops, 2233 sizeof(struct timers_private)); 2234 if (!tp) 2235 return -ENOMEM; 2236 2237 tp->pid = proc_pid(inode); 2238 tp->ns = inode->i_sb->s_fs_info; 2239 return 0; 2240 } 2241 2242 static const struct file_operations proc_timers_operations = { 2243 .open = proc_timers_open, 2244 .read = seq_read, 2245 .llseek = seq_lseek, 2246 .release = seq_release_private, 2247 }; 2248 #endif /* CONFIG_CHECKPOINT_RESTORE */ 2249 2250 static int proc_pident_instantiate(struct inode *dir, 2251 struct dentry *dentry, struct task_struct *task, const void *ptr) 2252 { 2253 const struct pid_entry *p = ptr; 2254 struct inode *inode; 2255 struct proc_inode *ei; 2256 2257 inode = proc_pid_make_inode(dir->i_sb, task); 2258 if (!inode) 2259 goto out; 2260 2261 ei = PROC_I(inode); 2262 inode->i_mode = p->mode; 2263 if (S_ISDIR(inode->i_mode)) 2264 set_nlink(inode, 2); /* Use getattr to fix if necessary */ 2265 if (p->iop) 2266 inode->i_op = p->iop; 2267 if (p->fop) 2268 inode->i_fop = p->fop; 2269 ei->op = p->op; 2270 d_set_d_op(dentry, &pid_dentry_operations); 2271 d_add(dentry, inode); 2272 /* Close the race of the process dying before we return the dentry */ 2273 if (pid_revalidate(dentry, 0)) 2274 return 0; 2275 out: 2276 return -ENOENT; 2277 } 2278 2279 static struct dentry *proc_pident_lookup(struct inode *dir, 2280 struct dentry *dentry, 2281 const struct pid_entry *ents, 2282 unsigned int nents) 2283 { 2284 int error; 2285 struct task_struct *task = get_proc_task(dir); 2286 const struct pid_entry *p, *last; 2287 2288 error = -ENOENT; 2289 2290 if (!task) 2291 goto out_no_task; 2292 2293 /* 2294 * Yes, it does not scale. And it should not. Don't add 2295 * new entries into /proc/<tgid>/ without very good reasons. 2296 */ 2297 last = &ents[nents - 1]; 2298 for (p = ents; p <= last; p++) { 2299 if (p->len != dentry->d_name.len) 2300 continue; 2301 if (!memcmp(dentry->d_name.name, p->name, p->len)) 2302 break; 2303 } 2304 if (p > last) 2305 goto out; 2306 2307 error = proc_pident_instantiate(dir, dentry, task, p); 2308 out: 2309 put_task_struct(task); 2310 out_no_task: 2311 return ERR_PTR(error); 2312 } 2313 2314 static int proc_pident_readdir(struct file *file, struct dir_context *ctx, 2315 const struct pid_entry *ents, unsigned int nents) 2316 { 2317 struct task_struct *task = get_proc_task(file_inode(file)); 2318 const struct pid_entry *p; 2319 2320 if (!task) 2321 return -ENOENT; 2322 2323 if (!dir_emit_dots(file, ctx)) 2324 goto out; 2325 2326 if (ctx->pos >= nents + 2) 2327 goto out; 2328 2329 for (p = ents + (ctx->pos - 2); p <= ents + nents - 1; p++) { 2330 if (!proc_fill_cache(file, ctx, p->name, p->len, 2331 proc_pident_instantiate, task, p)) 2332 break; 2333 ctx->pos++; 2334 } 2335 out: 2336 put_task_struct(task); 2337 return 0; 2338 } 2339 2340 #ifdef CONFIG_SECURITY 2341 static ssize_t proc_pid_attr_read(struct file * file, char __user * buf, 2342 size_t count, loff_t *ppos) 2343 { 2344 struct inode * inode = file_inode(file); 2345 char *p = NULL; 2346 ssize_t length; 2347 struct task_struct *task = get_proc_task(inode); 2348 2349 if (!task) 2350 return -ESRCH; 2351 2352 length = security_getprocattr(task, 2353 (char*)file->f_path.dentry->d_name.name, 2354 &p); 2355 put_task_struct(task); 2356 if (length > 0) 2357 length = simple_read_from_buffer(buf, count, ppos, p, length); 2358 kfree(p); 2359 return length; 2360 } 2361 2362 static ssize_t proc_pid_attr_write(struct file * file, const char __user * buf, 2363 size_t count, loff_t *ppos) 2364 { 2365 struct inode * inode = file_inode(file); 2366 char *page; 2367 ssize_t length; 2368 struct task_struct *task = get_proc_task(inode); 2369 2370 length = -ESRCH; 2371 if (!task) 2372 goto out_no_task; 2373 if (count > PAGE_SIZE) 2374 count = PAGE_SIZE; 2375 2376 /* No partial writes. */ 2377 length = -EINVAL; 2378 if (*ppos != 0) 2379 goto out; 2380 2381 length = -ENOMEM; 2382 page = (char*)__get_free_page(GFP_TEMPORARY); 2383 if (!page) 2384 goto out; 2385 2386 length = -EFAULT; 2387 if (copy_from_user(page, buf, count)) 2388 goto out_free; 2389 2390 /* Guard against adverse ptrace interaction */ 2391 length = mutex_lock_interruptible(&task->signal->cred_guard_mutex); 2392 if (length < 0) 2393 goto out_free; 2394 2395 length = security_setprocattr(task, 2396 (char*)file->f_path.dentry->d_name.name, 2397 (void*)page, count); 2398 mutex_unlock(&task->signal->cred_guard_mutex); 2399 out_free: 2400 free_page((unsigned long) page); 2401 out: 2402 put_task_struct(task); 2403 out_no_task: 2404 return length; 2405 } 2406 2407 static const struct file_operations proc_pid_attr_operations = { 2408 .read = proc_pid_attr_read, 2409 .write = proc_pid_attr_write, 2410 .llseek = generic_file_llseek, 2411 }; 2412 2413 static const struct pid_entry attr_dir_stuff[] = { 2414 REG("current", S_IRUGO|S_IWUGO, proc_pid_attr_operations), 2415 REG("prev", S_IRUGO, proc_pid_attr_operations), 2416 REG("exec", S_IRUGO|S_IWUGO, proc_pid_attr_operations), 2417 REG("fscreate", S_IRUGO|S_IWUGO, proc_pid_attr_operations), 2418 REG("keycreate", S_IRUGO|S_IWUGO, proc_pid_attr_operations), 2419 REG("sockcreate", S_IRUGO|S_IWUGO, proc_pid_attr_operations), 2420 }; 2421 2422 static int proc_attr_dir_readdir(struct file *file, struct dir_context *ctx) 2423 { 2424 return proc_pident_readdir(file, ctx, 2425 attr_dir_stuff, ARRAY_SIZE(attr_dir_stuff)); 2426 } 2427 2428 static const struct file_operations proc_attr_dir_operations = { 2429 .read = generic_read_dir, 2430 .iterate = proc_attr_dir_readdir, 2431 .llseek = default_llseek, 2432 }; 2433 2434 static struct dentry *proc_attr_dir_lookup(struct inode *dir, 2435 struct dentry *dentry, unsigned int flags) 2436 { 2437 return proc_pident_lookup(dir, dentry, 2438 attr_dir_stuff, ARRAY_SIZE(attr_dir_stuff)); 2439 } 2440 2441 static const struct inode_operations proc_attr_dir_inode_operations = { 2442 .lookup = proc_attr_dir_lookup, 2443 .getattr = pid_getattr, 2444 .setattr = proc_setattr, 2445 }; 2446 2447 #endif 2448 2449 #ifdef CONFIG_ELF_CORE 2450 static ssize_t proc_coredump_filter_read(struct file *file, char __user *buf, 2451 size_t count, loff_t *ppos) 2452 { 2453 struct task_struct *task = get_proc_task(file_inode(file)); 2454 struct mm_struct *mm; 2455 char buffer[PROC_NUMBUF]; 2456 size_t len; 2457 int ret; 2458 2459 if (!task) 2460 return -ESRCH; 2461 2462 ret = 0; 2463 mm = get_task_mm(task); 2464 if (mm) { 2465 len = snprintf(buffer, sizeof(buffer), "%08lx\n", 2466 ((mm->flags & MMF_DUMP_FILTER_MASK) >> 2467 MMF_DUMP_FILTER_SHIFT)); 2468 mmput(mm); 2469 ret = simple_read_from_buffer(buf, count, ppos, buffer, len); 2470 } 2471 2472 put_task_struct(task); 2473 2474 return ret; 2475 } 2476 2477 static ssize_t proc_coredump_filter_write(struct file *file, 2478 const char __user *buf, 2479 size_t count, 2480 loff_t *ppos) 2481 { 2482 struct task_struct *task; 2483 struct mm_struct *mm; 2484 char buffer[PROC_NUMBUF], *end; 2485 unsigned int val; 2486 int ret; 2487 int i; 2488 unsigned long mask; 2489 2490 ret = -EFAULT; 2491 memset(buffer, 0, sizeof(buffer)); 2492 if (count > sizeof(buffer) - 1) 2493 count = sizeof(buffer) - 1; 2494 if (copy_from_user(buffer, buf, count)) 2495 goto out_no_task; 2496 2497 ret = -EINVAL; 2498 val = (unsigned int)simple_strtoul(buffer, &end, 0); 2499 if (*end == '\n') 2500 end++; 2501 if (end - buffer == 0) 2502 goto out_no_task; 2503 2504 ret = -ESRCH; 2505 task = get_proc_task(file_inode(file)); 2506 if (!task) 2507 goto out_no_task; 2508 2509 ret = end - buffer; 2510 mm = get_task_mm(task); 2511 if (!mm) 2512 goto out_no_mm; 2513 2514 for (i = 0, mask = 1; i < MMF_DUMP_FILTER_BITS; i++, mask <<= 1) { 2515 if (val & mask) 2516 set_bit(i + MMF_DUMP_FILTER_SHIFT, &mm->flags); 2517 else 2518 clear_bit(i + MMF_DUMP_FILTER_SHIFT, &mm->flags); 2519 } 2520 2521 mmput(mm); 2522 out_no_mm: 2523 put_task_struct(task); 2524 out_no_task: 2525 return ret; 2526 } 2527 2528 static const struct file_operations proc_coredump_filter_operations = { 2529 .read = proc_coredump_filter_read, 2530 .write = proc_coredump_filter_write, 2531 .llseek = generic_file_llseek, 2532 }; 2533 #endif 2534 2535 #ifdef CONFIG_TASK_IO_ACCOUNTING 2536 static int do_io_accounting(struct task_struct *task, struct seq_file *m, int whole) 2537 { 2538 struct task_io_accounting acct = task->ioac; 2539 unsigned long flags; 2540 int result; 2541 2542 result = mutex_lock_killable(&task->signal->cred_guard_mutex); 2543 if (result) 2544 return result; 2545 2546 if (!ptrace_may_access(task, PTRACE_MODE_READ)) { 2547 result = -EACCES; 2548 goto out_unlock; 2549 } 2550 2551 if (whole && lock_task_sighand(task, &flags)) { 2552 struct task_struct *t = task; 2553 2554 task_io_accounting_add(&acct, &task->signal->ioac); 2555 while_each_thread(task, t) 2556 task_io_accounting_add(&acct, &t->ioac); 2557 2558 unlock_task_sighand(task, &flags); 2559 } 2560 seq_printf(m, 2561 "rchar: %llu\n" 2562 "wchar: %llu\n" 2563 "syscr: %llu\n" 2564 "syscw: %llu\n" 2565 "read_bytes: %llu\n" 2566 "write_bytes: %llu\n" 2567 "cancelled_write_bytes: %llu\n", 2568 (unsigned long long)acct.rchar, 2569 (unsigned long long)acct.wchar, 2570 (unsigned long long)acct.syscr, 2571 (unsigned long long)acct.syscw, 2572 (unsigned long long)acct.read_bytes, 2573 (unsigned long long)acct.write_bytes, 2574 (unsigned long long)acct.cancelled_write_bytes); 2575 result = 0; 2576 2577 out_unlock: 2578 mutex_unlock(&task->signal->cred_guard_mutex); 2579 return result; 2580 } 2581 2582 static int proc_tid_io_accounting(struct seq_file *m, struct pid_namespace *ns, 2583 struct pid *pid, struct task_struct *task) 2584 { 2585 return do_io_accounting(task, m, 0); 2586 } 2587 2588 static int proc_tgid_io_accounting(struct seq_file *m, struct pid_namespace *ns, 2589 struct pid *pid, struct task_struct *task) 2590 { 2591 return do_io_accounting(task, m, 1); 2592 } 2593 #endif /* CONFIG_TASK_IO_ACCOUNTING */ 2594 2595 #ifdef CONFIG_USER_NS 2596 static int proc_id_map_open(struct inode *inode, struct file *file, 2597 const struct seq_operations *seq_ops) 2598 { 2599 struct user_namespace *ns = NULL; 2600 struct task_struct *task; 2601 struct seq_file *seq; 2602 int ret = -EINVAL; 2603 2604 task = get_proc_task(inode); 2605 if (task) { 2606 rcu_read_lock(); 2607 ns = get_user_ns(task_cred_xxx(task, user_ns)); 2608 rcu_read_unlock(); 2609 put_task_struct(task); 2610 } 2611 if (!ns) 2612 goto err; 2613 2614 ret = seq_open(file, seq_ops); 2615 if (ret) 2616 goto err_put_ns; 2617 2618 seq = file->private_data; 2619 seq->private = ns; 2620 2621 return 0; 2622 err_put_ns: 2623 put_user_ns(ns); 2624 err: 2625 return ret; 2626 } 2627 2628 static int proc_id_map_release(struct inode *inode, struct file *file) 2629 { 2630 struct seq_file *seq = file->private_data; 2631 struct user_namespace *ns = seq->private; 2632 put_user_ns(ns); 2633 return seq_release(inode, file); 2634 } 2635 2636 static int proc_uid_map_open(struct inode *inode, struct file *file) 2637 { 2638 return proc_id_map_open(inode, file, &proc_uid_seq_operations); 2639 } 2640 2641 static int proc_gid_map_open(struct inode *inode, struct file *file) 2642 { 2643 return proc_id_map_open(inode, file, &proc_gid_seq_operations); 2644 } 2645 2646 static int proc_projid_map_open(struct inode *inode, struct file *file) 2647 { 2648 return proc_id_map_open(inode, file, &proc_projid_seq_operations); 2649 } 2650 2651 static const struct file_operations proc_uid_map_operations = { 2652 .open = proc_uid_map_open, 2653 .write = proc_uid_map_write, 2654 .read = seq_read, 2655 .llseek = seq_lseek, 2656 .release = proc_id_map_release, 2657 }; 2658 2659 static const struct file_operations proc_gid_map_operations = { 2660 .open = proc_gid_map_open, 2661 .write = proc_gid_map_write, 2662 .read = seq_read, 2663 .llseek = seq_lseek, 2664 .release = proc_id_map_release, 2665 }; 2666 2667 static const struct file_operations proc_projid_map_operations = { 2668 .open = proc_projid_map_open, 2669 .write = proc_projid_map_write, 2670 .read = seq_read, 2671 .llseek = seq_lseek, 2672 .release = proc_id_map_release, 2673 }; 2674 2675 static int proc_setgroups_open(struct inode *inode, struct file *file) 2676 { 2677 struct user_namespace *ns = NULL; 2678 struct task_struct *task; 2679 int ret; 2680 2681 ret = -ESRCH; 2682 task = get_proc_task(inode); 2683 if (task) { 2684 rcu_read_lock(); 2685 ns = get_user_ns(task_cred_xxx(task, user_ns)); 2686 rcu_read_unlock(); 2687 put_task_struct(task); 2688 } 2689 if (!ns) 2690 goto err; 2691 2692 if (file->f_mode & FMODE_WRITE) { 2693 ret = -EACCES; 2694 if (!ns_capable(ns, CAP_SYS_ADMIN)) 2695 goto err_put_ns; 2696 } 2697 2698 ret = single_open(file, &proc_setgroups_show, ns); 2699 if (ret) 2700 goto err_put_ns; 2701 2702 return 0; 2703 err_put_ns: 2704 put_user_ns(ns); 2705 err: 2706 return ret; 2707 } 2708 2709 static int proc_setgroups_release(struct inode *inode, struct file *file) 2710 { 2711 struct seq_file *seq = file->private_data; 2712 struct user_namespace *ns = seq->private; 2713 int ret = single_release(inode, file); 2714 put_user_ns(ns); 2715 return ret; 2716 } 2717 2718 static const struct file_operations proc_setgroups_operations = { 2719 .open = proc_setgroups_open, 2720 .write = proc_setgroups_write, 2721 .read = seq_read, 2722 .llseek = seq_lseek, 2723 .release = proc_setgroups_release, 2724 }; 2725 #endif /* CONFIG_USER_NS */ 2726 2727 static int proc_pid_personality(struct seq_file *m, struct pid_namespace *ns, 2728 struct pid *pid, struct task_struct *task) 2729 { 2730 int err = lock_trace(task); 2731 if (!err) { 2732 seq_printf(m, "%08x\n", task->personality); 2733 unlock_trace(task); 2734 } 2735 return err; 2736 } 2737 2738 /* 2739 * Thread groups 2740 */ 2741 static const struct file_operations proc_task_operations; 2742 static const struct inode_operations proc_task_inode_operations; 2743 2744 static const struct pid_entry tgid_base_stuff[] = { 2745 DIR("task", S_IRUGO|S_IXUGO, proc_task_inode_operations, proc_task_operations), 2746 DIR("fd", S_IRUSR|S_IXUSR, proc_fd_inode_operations, proc_fd_operations), 2747 #ifdef CONFIG_CHECKPOINT_RESTORE 2748 DIR("map_files", S_IRUSR|S_IXUSR, proc_map_files_inode_operations, proc_map_files_operations), 2749 #endif 2750 DIR("fdinfo", S_IRUSR|S_IXUSR, proc_fdinfo_inode_operations, proc_fdinfo_operations), 2751 DIR("ns", S_IRUSR|S_IXUGO, proc_ns_dir_inode_operations, proc_ns_dir_operations), 2752 #ifdef CONFIG_NET 2753 DIR("net", S_IRUGO|S_IXUGO, proc_net_inode_operations, proc_net_operations), 2754 #endif 2755 REG("environ", S_IRUSR, proc_environ_operations), 2756 ONE("auxv", S_IRUSR, proc_pid_auxv), 2757 ONE("status", S_IRUGO, proc_pid_status), 2758 ONE("personality", S_IRUSR, proc_pid_personality), 2759 ONE("limits", S_IRUGO, proc_pid_limits), 2760 #ifdef CONFIG_SCHED_DEBUG 2761 REG("sched", S_IRUGO|S_IWUSR, proc_pid_sched_operations), 2762 #endif 2763 #ifdef CONFIG_SCHED_AUTOGROUP 2764 REG("autogroup", S_IRUGO|S_IWUSR, proc_pid_sched_autogroup_operations), 2765 #endif 2766 REG("comm", S_IRUGO|S_IWUSR, proc_pid_set_comm_operations), 2767 #ifdef CONFIG_HAVE_ARCH_TRACEHOOK 2768 ONE("syscall", S_IRUSR, proc_pid_syscall), 2769 #endif 2770 REG("cmdline", S_IRUGO, proc_pid_cmdline_ops), 2771 ONE("stat", S_IRUGO, proc_tgid_stat), 2772 ONE("statm", S_IRUGO, proc_pid_statm), 2773 REG("maps", S_IRUGO, proc_pid_maps_operations), 2774 #ifdef CONFIG_NUMA 2775 REG("numa_maps", S_IRUGO, proc_pid_numa_maps_operations), 2776 #endif 2777 REG("mem", S_IRUSR|S_IWUSR, proc_mem_operations), 2778 LNK("cwd", proc_cwd_link), 2779 LNK("root", proc_root_link), 2780 LNK("exe", proc_exe_link), 2781 REG("mounts", S_IRUGO, proc_mounts_operations), 2782 REG("mountinfo", S_IRUGO, proc_mountinfo_operations), 2783 REG("mountstats", S_IRUSR, proc_mountstats_operations), 2784 #ifdef CONFIG_PROC_PAGE_MONITOR 2785 REG("clear_refs", S_IWUSR, proc_clear_refs_operations), 2786 REG("smaps", S_IRUGO, proc_pid_smaps_operations), 2787 REG("pagemap", S_IRUSR, proc_pagemap_operations), 2788 #endif 2789 #ifdef CONFIG_SECURITY 2790 DIR("attr", S_IRUGO|S_IXUGO, proc_attr_dir_inode_operations, proc_attr_dir_operations), 2791 #endif 2792 #ifdef CONFIG_KALLSYMS 2793 ONE("wchan", S_IRUGO, proc_pid_wchan), 2794 #endif 2795 #ifdef CONFIG_STACKTRACE 2796 ONE("stack", S_IRUSR, proc_pid_stack), 2797 #endif 2798 #ifdef CONFIG_SCHED_INFO 2799 ONE("schedstat", S_IRUGO, proc_pid_schedstat), 2800 #endif 2801 #ifdef CONFIG_LATENCYTOP 2802 REG("latency", S_IRUGO, proc_lstats_operations), 2803 #endif 2804 #ifdef CONFIG_PROC_PID_CPUSET 2805 ONE("cpuset", S_IRUGO, proc_cpuset_show), 2806 #endif 2807 #ifdef CONFIG_CGROUPS 2808 ONE("cgroup", S_IRUGO, proc_cgroup_show), 2809 #endif 2810 ONE("oom_score", S_IRUGO, proc_oom_score), 2811 REG("oom_adj", S_IRUGO|S_IWUSR, proc_oom_adj_operations), 2812 REG("oom_score_adj", S_IRUGO|S_IWUSR, proc_oom_score_adj_operations), 2813 #ifdef CONFIG_AUDITSYSCALL 2814 REG("loginuid", S_IWUSR|S_IRUGO, proc_loginuid_operations), 2815 REG("sessionid", S_IRUGO, proc_sessionid_operations), 2816 #endif 2817 #ifdef CONFIG_FAULT_INJECTION 2818 REG("make-it-fail", S_IRUGO|S_IWUSR, proc_fault_inject_operations), 2819 #endif 2820 #ifdef CONFIG_ELF_CORE 2821 REG("coredump_filter", S_IRUGO|S_IWUSR, proc_coredump_filter_operations), 2822 #endif 2823 #ifdef CONFIG_TASK_IO_ACCOUNTING 2824 ONE("io", S_IRUSR, proc_tgid_io_accounting), 2825 #endif 2826 #ifdef CONFIG_HARDWALL 2827 ONE("hardwall", S_IRUGO, proc_pid_hardwall), 2828 #endif 2829 #ifdef CONFIG_USER_NS 2830 REG("uid_map", S_IRUGO|S_IWUSR, proc_uid_map_operations), 2831 REG("gid_map", S_IRUGO|S_IWUSR, proc_gid_map_operations), 2832 REG("projid_map", S_IRUGO|S_IWUSR, proc_projid_map_operations), 2833 REG("setgroups", S_IRUGO|S_IWUSR, proc_setgroups_operations), 2834 #endif 2835 #ifdef CONFIG_CHECKPOINT_RESTORE 2836 REG("timers", S_IRUGO, proc_timers_operations), 2837 #endif 2838 }; 2839 2840 static int proc_tgid_base_readdir(struct file *file, struct dir_context *ctx) 2841 { 2842 return proc_pident_readdir(file, ctx, 2843 tgid_base_stuff, ARRAY_SIZE(tgid_base_stuff)); 2844 } 2845 2846 static const struct file_operations proc_tgid_base_operations = { 2847 .read = generic_read_dir, 2848 .iterate = proc_tgid_base_readdir, 2849 .llseek = default_llseek, 2850 }; 2851 2852 static struct dentry *proc_tgid_base_lookup(struct inode *dir, struct dentry *dentry, unsigned int flags) 2853 { 2854 return proc_pident_lookup(dir, dentry, 2855 tgid_base_stuff, ARRAY_SIZE(tgid_base_stuff)); 2856 } 2857 2858 static const struct inode_operations proc_tgid_base_inode_operations = { 2859 .lookup = proc_tgid_base_lookup, 2860 .getattr = pid_getattr, 2861 .setattr = proc_setattr, 2862 .permission = proc_pid_permission, 2863 }; 2864 2865 static void proc_flush_task_mnt(struct vfsmount *mnt, pid_t pid, pid_t tgid) 2866 { 2867 struct dentry *dentry, *leader, *dir; 2868 char buf[PROC_NUMBUF]; 2869 struct qstr name; 2870 2871 name.name = buf; 2872 name.len = snprintf(buf, sizeof(buf), "%d", pid); 2873 /* no ->d_hash() rejects on procfs */ 2874 dentry = d_hash_and_lookup(mnt->mnt_root, &name); 2875 if (dentry) { 2876 d_invalidate(dentry); 2877 dput(dentry); 2878 } 2879 2880 if (pid == tgid) 2881 return; 2882 2883 name.name = buf; 2884 name.len = snprintf(buf, sizeof(buf), "%d", tgid); 2885 leader = d_hash_and_lookup(mnt->mnt_root, &name); 2886 if (!leader) 2887 goto out; 2888 2889 name.name = "task"; 2890 name.len = strlen(name.name); 2891 dir = d_hash_and_lookup(leader, &name); 2892 if (!dir) 2893 goto out_put_leader; 2894 2895 name.name = buf; 2896 name.len = snprintf(buf, sizeof(buf), "%d", pid); 2897 dentry = d_hash_and_lookup(dir, &name); 2898 if (dentry) { 2899 d_invalidate(dentry); 2900 dput(dentry); 2901 } 2902 2903 dput(dir); 2904 out_put_leader: 2905 dput(leader); 2906 out: 2907 return; 2908 } 2909 2910 /** 2911 * proc_flush_task - Remove dcache entries for @task from the /proc dcache. 2912 * @task: task that should be flushed. 2913 * 2914 * When flushing dentries from proc, one needs to flush them from global 2915 * proc (proc_mnt) and from all the namespaces' procs this task was seen 2916 * in. This call is supposed to do all of this job. 2917 * 2918 * Looks in the dcache for 2919 * /proc/@pid 2920 * /proc/@tgid/task/@pid 2921 * if either directory is present flushes it and all of it'ts children 2922 * from the dcache. 2923 * 2924 * It is safe and reasonable to cache /proc entries for a task until 2925 * that task exits. After that they just clog up the dcache with 2926 * useless entries, possibly causing useful dcache entries to be 2927 * flushed instead. This routine is proved to flush those useless 2928 * dcache entries at process exit time. 2929 * 2930 * NOTE: This routine is just an optimization so it does not guarantee 2931 * that no dcache entries will exist at process exit time it 2932 * just makes it very unlikely that any will persist. 2933 */ 2934 2935 void proc_flush_task(struct task_struct *task) 2936 { 2937 int i; 2938 struct pid *pid, *tgid; 2939 struct upid *upid; 2940 2941 pid = task_pid(task); 2942 tgid = task_tgid(task); 2943 2944 for (i = 0; i <= pid->level; i++) { 2945 upid = &pid->numbers[i]; 2946 proc_flush_task_mnt(upid->ns->proc_mnt, upid->nr, 2947 tgid->numbers[i].nr); 2948 } 2949 } 2950 2951 static int proc_pid_instantiate(struct inode *dir, 2952 struct dentry * dentry, 2953 struct task_struct *task, const void *ptr) 2954 { 2955 struct inode *inode; 2956 2957 inode = proc_pid_make_inode(dir->i_sb, task); 2958 if (!inode) 2959 goto out; 2960 2961 inode->i_mode = S_IFDIR|S_IRUGO|S_IXUGO; 2962 inode->i_op = &proc_tgid_base_inode_operations; 2963 inode->i_fop = &proc_tgid_base_operations; 2964 inode->i_flags|=S_IMMUTABLE; 2965 2966 set_nlink(inode, 2 + pid_entry_count_dirs(tgid_base_stuff, 2967 ARRAY_SIZE(tgid_base_stuff))); 2968 2969 d_set_d_op(dentry, &pid_dentry_operations); 2970 2971 d_add(dentry, inode); 2972 /* Close the race of the process dying before we return the dentry */ 2973 if (pid_revalidate(dentry, 0)) 2974 return 0; 2975 out: 2976 return -ENOENT; 2977 } 2978 2979 struct dentry *proc_pid_lookup(struct inode *dir, struct dentry * dentry, unsigned int flags) 2980 { 2981 int result = -ENOENT; 2982 struct task_struct *task; 2983 unsigned tgid; 2984 struct pid_namespace *ns; 2985 2986 tgid = name_to_int(&dentry->d_name); 2987 if (tgid == ~0U) 2988 goto out; 2989 2990 ns = dentry->d_sb->s_fs_info; 2991 rcu_read_lock(); 2992 task = find_task_by_pid_ns(tgid, ns); 2993 if (task) 2994 get_task_struct(task); 2995 rcu_read_unlock(); 2996 if (!task) 2997 goto out; 2998 2999 result = proc_pid_instantiate(dir, dentry, task, NULL); 3000 put_task_struct(task); 3001 out: 3002 return ERR_PTR(result); 3003 } 3004 3005 /* 3006 * Find the first task with tgid >= tgid 3007 * 3008 */ 3009 struct tgid_iter { 3010 unsigned int tgid; 3011 struct task_struct *task; 3012 }; 3013 static struct tgid_iter next_tgid(struct pid_namespace *ns, struct tgid_iter iter) 3014 { 3015 struct pid *pid; 3016 3017 if (iter.task) 3018 put_task_struct(iter.task); 3019 rcu_read_lock(); 3020 retry: 3021 iter.task = NULL; 3022 pid = find_ge_pid(iter.tgid, ns); 3023 if (pid) { 3024 iter.tgid = pid_nr_ns(pid, ns); 3025 iter.task = pid_task(pid, PIDTYPE_PID); 3026 /* What we to know is if the pid we have find is the 3027 * pid of a thread_group_leader. Testing for task 3028 * being a thread_group_leader is the obvious thing 3029 * todo but there is a window when it fails, due to 3030 * the pid transfer logic in de_thread. 3031 * 3032 * So we perform the straight forward test of seeing 3033 * if the pid we have found is the pid of a thread 3034 * group leader, and don't worry if the task we have 3035 * found doesn't happen to be a thread group leader. 3036 * As we don't care in the case of readdir. 3037 */ 3038 if (!iter.task || !has_group_leader_pid(iter.task)) { 3039 iter.tgid += 1; 3040 goto retry; 3041 } 3042 get_task_struct(iter.task); 3043 } 3044 rcu_read_unlock(); 3045 return iter; 3046 } 3047 3048 #define TGID_OFFSET (FIRST_PROCESS_ENTRY + 2) 3049 3050 /* for the /proc/ directory itself, after non-process stuff has been done */ 3051 int proc_pid_readdir(struct file *file, struct dir_context *ctx) 3052 { 3053 struct tgid_iter iter; 3054 struct pid_namespace *ns = file_inode(file)->i_sb->s_fs_info; 3055 loff_t pos = ctx->pos; 3056 3057 if (pos >= PID_MAX_LIMIT + TGID_OFFSET) 3058 return 0; 3059 3060 if (pos == TGID_OFFSET - 2) { 3061 struct inode *inode = d_inode(ns->proc_self); 3062 if (!dir_emit(ctx, "self", 4, inode->i_ino, DT_LNK)) 3063 return 0; 3064 ctx->pos = pos = pos + 1; 3065 } 3066 if (pos == TGID_OFFSET - 1) { 3067 struct inode *inode = d_inode(ns->proc_thread_self); 3068 if (!dir_emit(ctx, "thread-self", 11, inode->i_ino, DT_LNK)) 3069 return 0; 3070 ctx->pos = pos = pos + 1; 3071 } 3072 iter.tgid = pos - TGID_OFFSET; 3073 iter.task = NULL; 3074 for (iter = next_tgid(ns, iter); 3075 iter.task; 3076 iter.tgid += 1, iter = next_tgid(ns, iter)) { 3077 char name[PROC_NUMBUF]; 3078 int len; 3079 if (!has_pid_permissions(ns, iter.task, 2)) 3080 continue; 3081 3082 len = snprintf(name, sizeof(name), "%d", iter.tgid); 3083 ctx->pos = iter.tgid + TGID_OFFSET; 3084 if (!proc_fill_cache(file, ctx, name, len, 3085 proc_pid_instantiate, iter.task, NULL)) { 3086 put_task_struct(iter.task); 3087 return 0; 3088 } 3089 } 3090 ctx->pos = PID_MAX_LIMIT + TGID_OFFSET; 3091 return 0; 3092 } 3093 3094 /* 3095 * Tasks 3096 */ 3097 static const struct pid_entry tid_base_stuff[] = { 3098 DIR("fd", S_IRUSR|S_IXUSR, proc_fd_inode_operations, proc_fd_operations), 3099 DIR("fdinfo", S_IRUSR|S_IXUSR, proc_fdinfo_inode_operations, proc_fdinfo_operations), 3100 DIR("ns", S_IRUSR|S_IXUGO, proc_ns_dir_inode_operations, proc_ns_dir_operations), 3101 #ifdef CONFIG_NET 3102 DIR("net", S_IRUGO|S_IXUGO, proc_net_inode_operations, proc_net_operations), 3103 #endif 3104 REG("environ", S_IRUSR, proc_environ_operations), 3105 ONE("auxv", S_IRUSR, proc_pid_auxv), 3106 ONE("status", S_IRUGO, proc_pid_status), 3107 ONE("personality", S_IRUSR, proc_pid_personality), 3108 ONE("limits", S_IRUGO, proc_pid_limits), 3109 #ifdef CONFIG_SCHED_DEBUG 3110 REG("sched", S_IRUGO|S_IWUSR, proc_pid_sched_operations), 3111 #endif 3112 REG("comm", S_IRUGO|S_IWUSR, proc_pid_set_comm_operations), 3113 #ifdef CONFIG_HAVE_ARCH_TRACEHOOK 3114 ONE("syscall", S_IRUSR, proc_pid_syscall), 3115 #endif 3116 REG("cmdline", S_IRUGO, proc_pid_cmdline_ops), 3117 ONE("stat", S_IRUGO, proc_tid_stat), 3118 ONE("statm", S_IRUGO, proc_pid_statm), 3119 REG("maps", S_IRUGO, proc_tid_maps_operations), 3120 #ifdef CONFIG_PROC_CHILDREN 3121 REG("children", S_IRUGO, proc_tid_children_operations), 3122 #endif 3123 #ifdef CONFIG_NUMA 3124 REG("numa_maps", S_IRUGO, proc_tid_numa_maps_operations), 3125 #endif 3126 REG("mem", S_IRUSR|S_IWUSR, proc_mem_operations), 3127 LNK("cwd", proc_cwd_link), 3128 LNK("root", proc_root_link), 3129 LNK("exe", proc_exe_link), 3130 REG("mounts", S_IRUGO, proc_mounts_operations), 3131 REG("mountinfo", S_IRUGO, proc_mountinfo_operations), 3132 #ifdef CONFIG_PROC_PAGE_MONITOR 3133 REG("clear_refs", S_IWUSR, proc_clear_refs_operations), 3134 REG("smaps", S_IRUGO, proc_tid_smaps_operations), 3135 REG("pagemap", S_IRUSR, proc_pagemap_operations), 3136 #endif 3137 #ifdef CONFIG_SECURITY 3138 DIR("attr", S_IRUGO|S_IXUGO, proc_attr_dir_inode_operations, proc_attr_dir_operations), 3139 #endif 3140 #ifdef CONFIG_KALLSYMS 3141 ONE("wchan", S_IRUGO, proc_pid_wchan), 3142 #endif 3143 #ifdef CONFIG_STACKTRACE 3144 ONE("stack", S_IRUSR, proc_pid_stack), 3145 #endif 3146 #ifdef CONFIG_SCHED_INFO 3147 ONE("schedstat", S_IRUGO, proc_pid_schedstat), 3148 #endif 3149 #ifdef CONFIG_LATENCYTOP 3150 REG("latency", S_IRUGO, proc_lstats_operations), 3151 #endif 3152 #ifdef CONFIG_PROC_PID_CPUSET 3153 ONE("cpuset", S_IRUGO, proc_cpuset_show), 3154 #endif 3155 #ifdef CONFIG_CGROUPS 3156 ONE("cgroup", S_IRUGO, proc_cgroup_show), 3157 #endif 3158 ONE("oom_score", S_IRUGO, proc_oom_score), 3159 REG("oom_adj", S_IRUGO|S_IWUSR, proc_oom_adj_operations), 3160 REG("oom_score_adj", S_IRUGO|S_IWUSR, proc_oom_score_adj_operations), 3161 #ifdef CONFIG_AUDITSYSCALL 3162 REG("loginuid", S_IWUSR|S_IRUGO, proc_loginuid_operations), 3163 REG("sessionid", S_IRUGO, proc_sessionid_operations), 3164 #endif 3165 #ifdef CONFIG_FAULT_INJECTION 3166 REG("make-it-fail", S_IRUGO|S_IWUSR, proc_fault_inject_operations), 3167 #endif 3168 #ifdef CONFIG_TASK_IO_ACCOUNTING 3169 ONE("io", S_IRUSR, proc_tid_io_accounting), 3170 #endif 3171 #ifdef CONFIG_HARDWALL 3172 ONE("hardwall", S_IRUGO, proc_pid_hardwall), 3173 #endif 3174 #ifdef CONFIG_USER_NS 3175 REG("uid_map", S_IRUGO|S_IWUSR, proc_uid_map_operations), 3176 REG("gid_map", S_IRUGO|S_IWUSR, proc_gid_map_operations), 3177 REG("projid_map", S_IRUGO|S_IWUSR, proc_projid_map_operations), 3178 REG("setgroups", S_IRUGO|S_IWUSR, proc_setgroups_operations), 3179 #endif 3180 }; 3181 3182 static int proc_tid_base_readdir(struct file *file, struct dir_context *ctx) 3183 { 3184 return proc_pident_readdir(file, ctx, 3185 tid_base_stuff, ARRAY_SIZE(tid_base_stuff)); 3186 } 3187 3188 static struct dentry *proc_tid_base_lookup(struct inode *dir, struct dentry *dentry, unsigned int flags) 3189 { 3190 return proc_pident_lookup(dir, dentry, 3191 tid_base_stuff, ARRAY_SIZE(tid_base_stuff)); 3192 } 3193 3194 static const struct file_operations proc_tid_base_operations = { 3195 .read = generic_read_dir, 3196 .iterate = proc_tid_base_readdir, 3197 .llseek = default_llseek, 3198 }; 3199 3200 static const struct inode_operations proc_tid_base_inode_operations = { 3201 .lookup = proc_tid_base_lookup, 3202 .getattr = pid_getattr, 3203 .setattr = proc_setattr, 3204 }; 3205 3206 static int proc_task_instantiate(struct inode *dir, 3207 struct dentry *dentry, struct task_struct *task, const void *ptr) 3208 { 3209 struct inode *inode; 3210 inode = proc_pid_make_inode(dir->i_sb, task); 3211 3212 if (!inode) 3213 goto out; 3214 inode->i_mode = S_IFDIR|S_IRUGO|S_IXUGO; 3215 inode->i_op = &proc_tid_base_inode_operations; 3216 inode->i_fop = &proc_tid_base_operations; 3217 inode->i_flags|=S_IMMUTABLE; 3218 3219 set_nlink(inode, 2 + pid_entry_count_dirs(tid_base_stuff, 3220 ARRAY_SIZE(tid_base_stuff))); 3221 3222 d_set_d_op(dentry, &pid_dentry_operations); 3223 3224 d_add(dentry, inode); 3225 /* Close the race of the process dying before we return the dentry */ 3226 if (pid_revalidate(dentry, 0)) 3227 return 0; 3228 out: 3229 return -ENOENT; 3230 } 3231 3232 static struct dentry *proc_task_lookup(struct inode *dir, struct dentry * dentry, unsigned int flags) 3233 { 3234 int result = -ENOENT; 3235 struct task_struct *task; 3236 struct task_struct *leader = get_proc_task(dir); 3237 unsigned tid; 3238 struct pid_namespace *ns; 3239 3240 if (!leader) 3241 goto out_no_task; 3242 3243 tid = name_to_int(&dentry->d_name); 3244 if (tid == ~0U) 3245 goto out; 3246 3247 ns = dentry->d_sb->s_fs_info; 3248 rcu_read_lock(); 3249 task = find_task_by_pid_ns(tid, ns); 3250 if (task) 3251 get_task_struct(task); 3252 rcu_read_unlock(); 3253 if (!task) 3254 goto out; 3255 if (!same_thread_group(leader, task)) 3256 goto out_drop_task; 3257 3258 result = proc_task_instantiate(dir, dentry, task, NULL); 3259 out_drop_task: 3260 put_task_struct(task); 3261 out: 3262 put_task_struct(leader); 3263 out_no_task: 3264 return ERR_PTR(result); 3265 } 3266 3267 /* 3268 * Find the first tid of a thread group to return to user space. 3269 * 3270 * Usually this is just the thread group leader, but if the users 3271 * buffer was too small or there was a seek into the middle of the 3272 * directory we have more work todo. 3273 * 3274 * In the case of a short read we start with find_task_by_pid. 3275 * 3276 * In the case of a seek we start with the leader and walk nr 3277 * threads past it. 3278 */ 3279 static struct task_struct *first_tid(struct pid *pid, int tid, loff_t f_pos, 3280 struct pid_namespace *ns) 3281 { 3282 struct task_struct *pos, *task; 3283 unsigned long nr = f_pos; 3284 3285 if (nr != f_pos) /* 32bit overflow? */ 3286 return NULL; 3287 3288 rcu_read_lock(); 3289 task = pid_task(pid, PIDTYPE_PID); 3290 if (!task) 3291 goto fail; 3292 3293 /* Attempt to start with the tid of a thread */ 3294 if (tid && nr) { 3295 pos = find_task_by_pid_ns(tid, ns); 3296 if (pos && same_thread_group(pos, task)) 3297 goto found; 3298 } 3299 3300 /* If nr exceeds the number of threads there is nothing todo */ 3301 if (nr >= get_nr_threads(task)) 3302 goto fail; 3303 3304 /* If we haven't found our starting place yet start 3305 * with the leader and walk nr threads forward. 3306 */ 3307 pos = task = task->group_leader; 3308 do { 3309 if (!nr--) 3310 goto found; 3311 } while_each_thread(task, pos); 3312 fail: 3313 pos = NULL; 3314 goto out; 3315 found: 3316 get_task_struct(pos); 3317 out: 3318 rcu_read_unlock(); 3319 return pos; 3320 } 3321 3322 /* 3323 * Find the next thread in the thread list. 3324 * Return NULL if there is an error or no next thread. 3325 * 3326 * The reference to the input task_struct is released. 3327 */ 3328 static struct task_struct *next_tid(struct task_struct *start) 3329 { 3330 struct task_struct *pos = NULL; 3331 rcu_read_lock(); 3332 if (pid_alive(start)) { 3333 pos = next_thread(start); 3334 if (thread_group_leader(pos)) 3335 pos = NULL; 3336 else 3337 get_task_struct(pos); 3338 } 3339 rcu_read_unlock(); 3340 put_task_struct(start); 3341 return pos; 3342 } 3343 3344 /* for the /proc/TGID/task/ directories */ 3345 static int proc_task_readdir(struct file *file, struct dir_context *ctx) 3346 { 3347 struct inode *inode = file_inode(file); 3348 struct task_struct *task; 3349 struct pid_namespace *ns; 3350 int tid; 3351 3352 if (proc_inode_is_dead(inode)) 3353 return -ENOENT; 3354 3355 if (!dir_emit_dots(file, ctx)) 3356 return 0; 3357 3358 /* f_version caches the tgid value that the last readdir call couldn't 3359 * return. lseek aka telldir automagically resets f_version to 0. 3360 */ 3361 ns = inode->i_sb->s_fs_info; 3362 tid = (int)file->f_version; 3363 file->f_version = 0; 3364 for (task = first_tid(proc_pid(inode), tid, ctx->pos - 2, ns); 3365 task; 3366 task = next_tid(task), ctx->pos++) { 3367 char name[PROC_NUMBUF]; 3368 int len; 3369 tid = task_pid_nr_ns(task, ns); 3370 len = snprintf(name, sizeof(name), "%d", tid); 3371 if (!proc_fill_cache(file, ctx, name, len, 3372 proc_task_instantiate, task, NULL)) { 3373 /* returning this tgid failed, save it as the first 3374 * pid for the next readir call */ 3375 file->f_version = (u64)tid; 3376 put_task_struct(task); 3377 break; 3378 } 3379 } 3380 3381 return 0; 3382 } 3383 3384 static int proc_task_getattr(struct vfsmount *mnt, struct dentry *dentry, struct kstat *stat) 3385 { 3386 struct inode *inode = d_inode(dentry); 3387 struct task_struct *p = get_proc_task(inode); 3388 generic_fillattr(inode, stat); 3389 3390 if (p) { 3391 stat->nlink += get_nr_threads(p); 3392 put_task_struct(p); 3393 } 3394 3395 return 0; 3396 } 3397 3398 static const struct inode_operations proc_task_inode_operations = { 3399 .lookup = proc_task_lookup, 3400 .getattr = proc_task_getattr, 3401 .setattr = proc_setattr, 3402 .permission = proc_pid_permission, 3403 }; 3404 3405 static const struct file_operations proc_task_operations = { 3406 .read = generic_read_dir, 3407 .iterate = proc_task_readdir, 3408 .llseek = default_llseek, 3409 }; 3410