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