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