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