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/rcupdate.h> 67 #include <linux/kallsyms.h> 68 #include <linux/stacktrace.h> 69 #include <linux/resource.h> 70 #include <linux/module.h> 71 #include <linux/mount.h> 72 #include <linux/security.h> 73 #include <linux/ptrace.h> 74 #include <linux/tracehook.h> 75 #include <linux/cgroup.h> 76 #include <linux/cpuset.h> 77 #include <linux/audit.h> 78 #include <linux/poll.h> 79 #include <linux/nsproxy.h> 80 #include <linux/oom.h> 81 #include <linux/elf.h> 82 #include <linux/pid_namespace.h> 83 #include <linux/fs_struct.h> 84 #include "internal.h" 85 86 /* NOTE: 87 * Implementing inode permission operations in /proc is almost 88 * certainly an error. Permission checks need to happen during 89 * each system call not at open time. The reason is that most of 90 * what we wish to check for permissions in /proc varies at runtime. 91 * 92 * The classic example of a problem is opening file descriptors 93 * in /proc for a task before it execs a suid executable. 94 */ 95 96 struct pid_entry { 97 char *name; 98 int len; 99 mode_t mode; 100 const struct inode_operations *iop; 101 const struct file_operations *fop; 102 union proc_op op; 103 }; 104 105 #define NOD(NAME, MODE, IOP, FOP, OP) { \ 106 .name = (NAME), \ 107 .len = sizeof(NAME) - 1, \ 108 .mode = MODE, \ 109 .iop = IOP, \ 110 .fop = FOP, \ 111 .op = OP, \ 112 } 113 114 #define DIR(NAME, MODE, iops, fops) \ 115 NOD(NAME, (S_IFDIR|(MODE)), &iops, &fops, {} ) 116 #define LNK(NAME, get_link) \ 117 NOD(NAME, (S_IFLNK|S_IRWXUGO), \ 118 &proc_pid_link_inode_operations, NULL, \ 119 { .proc_get_link = get_link } ) 120 #define REG(NAME, MODE, fops) \ 121 NOD(NAME, (S_IFREG|(MODE)), NULL, &fops, {}) 122 #define INF(NAME, MODE, read) \ 123 NOD(NAME, (S_IFREG|(MODE)), \ 124 NULL, &proc_info_file_operations, \ 125 { .proc_read = read } ) 126 #define ONE(NAME, MODE, show) \ 127 NOD(NAME, (S_IFREG|(MODE)), \ 128 NULL, &proc_single_file_operations, \ 129 { .proc_show = show } ) 130 131 /* 132 * Count the number of hardlinks for the pid_entry table, excluding the . 133 * and .. links. 134 */ 135 static unsigned int pid_entry_count_dirs(const struct pid_entry *entries, 136 unsigned int n) 137 { 138 unsigned int i; 139 unsigned int count; 140 141 count = 0; 142 for (i = 0; i < n; ++i) { 143 if (S_ISDIR(entries[i].mode)) 144 ++count; 145 } 146 147 return count; 148 } 149 150 static int get_fs_path(struct task_struct *task, struct path *path, bool root) 151 { 152 struct fs_struct *fs; 153 int result = -ENOENT; 154 155 task_lock(task); 156 fs = task->fs; 157 if (fs) { 158 read_lock(&fs->lock); 159 *path = root ? fs->root : fs->pwd; 160 path_get(path); 161 read_unlock(&fs->lock); 162 result = 0; 163 } 164 task_unlock(task); 165 return result; 166 } 167 168 static int get_nr_threads(struct task_struct *tsk) 169 { 170 unsigned long flags; 171 int count = 0; 172 173 if (lock_task_sighand(tsk, &flags)) { 174 count = atomic_read(&tsk->signal->count); 175 unlock_task_sighand(tsk, &flags); 176 } 177 return count; 178 } 179 180 static int proc_cwd_link(struct inode *inode, struct path *path) 181 { 182 struct task_struct *task = get_proc_task(inode); 183 int result = -ENOENT; 184 185 if (task) { 186 result = get_fs_path(task, path, 0); 187 put_task_struct(task); 188 } 189 return result; 190 } 191 192 static int proc_root_link(struct inode *inode, struct path *path) 193 { 194 struct task_struct *task = get_proc_task(inode); 195 int result = -ENOENT; 196 197 if (task) { 198 result = get_fs_path(task, path, 1); 199 put_task_struct(task); 200 } 201 return result; 202 } 203 204 /* 205 * Return zero if current may access user memory in @task, -error if not. 206 */ 207 static int check_mem_permission(struct task_struct *task) 208 { 209 /* 210 * A task can always look at itself, in case it chooses 211 * to use system calls instead of load instructions. 212 */ 213 if (task == current) 214 return 0; 215 216 /* 217 * If current is actively ptrace'ing, and would also be 218 * permitted to freshly attach with ptrace now, permit it. 219 */ 220 if (task_is_stopped_or_traced(task)) { 221 int match; 222 rcu_read_lock(); 223 match = (tracehook_tracer_task(task) == current); 224 rcu_read_unlock(); 225 if (match && ptrace_may_access(task, PTRACE_MODE_ATTACH)) 226 return 0; 227 } 228 229 /* 230 * Noone else is allowed. 231 */ 232 return -EPERM; 233 } 234 235 struct mm_struct *mm_for_maps(struct task_struct *task) 236 { 237 struct mm_struct *mm; 238 239 if (mutex_lock_killable(&task->cred_guard_mutex)) 240 return NULL; 241 242 mm = get_task_mm(task); 243 if (mm && mm != current->mm && 244 !ptrace_may_access(task, PTRACE_MODE_READ)) { 245 mmput(mm); 246 mm = NULL; 247 } 248 mutex_unlock(&task->cred_guard_mutex); 249 250 return mm; 251 } 252 253 static int proc_pid_cmdline(struct task_struct *task, char * buffer) 254 { 255 int res = 0; 256 unsigned int len; 257 struct mm_struct *mm = get_task_mm(task); 258 if (!mm) 259 goto out; 260 if (!mm->arg_end) 261 goto out_mm; /* Shh! No looking before we're done */ 262 263 len = mm->arg_end - mm->arg_start; 264 265 if (len > PAGE_SIZE) 266 len = PAGE_SIZE; 267 268 res = access_process_vm(task, mm->arg_start, buffer, len, 0); 269 270 // If the nul at the end of args has been overwritten, then 271 // assume application is using setproctitle(3). 272 if (res > 0 && buffer[res-1] != '\0' && len < PAGE_SIZE) { 273 len = strnlen(buffer, res); 274 if (len < res) { 275 res = len; 276 } else { 277 len = mm->env_end - mm->env_start; 278 if (len > PAGE_SIZE - res) 279 len = PAGE_SIZE - res; 280 res += access_process_vm(task, mm->env_start, buffer+res, len, 0); 281 res = strnlen(buffer, res); 282 } 283 } 284 out_mm: 285 mmput(mm); 286 out: 287 return res; 288 } 289 290 static int proc_pid_auxv(struct task_struct *task, char *buffer) 291 { 292 int res = 0; 293 struct mm_struct *mm = get_task_mm(task); 294 if (mm) { 295 unsigned int nwords = 0; 296 do { 297 nwords += 2; 298 } while (mm->saved_auxv[nwords - 2] != 0); /* AT_NULL */ 299 res = nwords * sizeof(mm->saved_auxv[0]); 300 if (res > PAGE_SIZE) 301 res = PAGE_SIZE; 302 memcpy(buffer, mm->saved_auxv, res); 303 mmput(mm); 304 } 305 return res; 306 } 307 308 309 #ifdef CONFIG_KALLSYMS 310 /* 311 * Provides a wchan file via kallsyms in a proper one-value-per-file format. 312 * Returns the resolved symbol. If that fails, simply return the address. 313 */ 314 static int proc_pid_wchan(struct task_struct *task, char *buffer) 315 { 316 unsigned long wchan; 317 char symname[KSYM_NAME_LEN]; 318 319 wchan = get_wchan(task); 320 321 if (lookup_symbol_name(wchan, symname) < 0) 322 if (!ptrace_may_access(task, PTRACE_MODE_READ)) 323 return 0; 324 else 325 return sprintf(buffer, "%lu", wchan); 326 else 327 return sprintf(buffer, "%s", symname); 328 } 329 #endif /* CONFIG_KALLSYMS */ 330 331 #ifdef CONFIG_STACKTRACE 332 333 #define MAX_STACK_TRACE_DEPTH 64 334 335 static int proc_pid_stack(struct seq_file *m, struct pid_namespace *ns, 336 struct pid *pid, struct task_struct *task) 337 { 338 struct stack_trace trace; 339 unsigned long *entries; 340 int i; 341 342 entries = kmalloc(MAX_STACK_TRACE_DEPTH * sizeof(*entries), GFP_KERNEL); 343 if (!entries) 344 return -ENOMEM; 345 346 trace.nr_entries = 0; 347 trace.max_entries = MAX_STACK_TRACE_DEPTH; 348 trace.entries = entries; 349 trace.skip = 0; 350 save_stack_trace_tsk(task, &trace); 351 352 for (i = 0; i < trace.nr_entries; i++) { 353 seq_printf(m, "[<%p>] %pS\n", 354 (void *)entries[i], (void *)entries[i]); 355 } 356 kfree(entries); 357 358 return 0; 359 } 360 #endif 361 362 #ifdef CONFIG_SCHEDSTATS 363 /* 364 * Provides /proc/PID/schedstat 365 */ 366 static int proc_pid_schedstat(struct task_struct *task, char *buffer) 367 { 368 return sprintf(buffer, "%llu %llu %lu\n", 369 (unsigned long long)task->se.sum_exec_runtime, 370 (unsigned long long)task->sched_info.run_delay, 371 task->sched_info.pcount); 372 } 373 #endif 374 375 #ifdef CONFIG_LATENCYTOP 376 static int lstats_show_proc(struct seq_file *m, void *v) 377 { 378 int i; 379 struct inode *inode = m->private; 380 struct task_struct *task = get_proc_task(inode); 381 382 if (!task) 383 return -ESRCH; 384 seq_puts(m, "Latency Top version : v0.1\n"); 385 for (i = 0; i < 32; i++) { 386 if (task->latency_record[i].backtrace[0]) { 387 int q; 388 seq_printf(m, "%i %li %li ", 389 task->latency_record[i].count, 390 task->latency_record[i].time, 391 task->latency_record[i].max); 392 for (q = 0; q < LT_BACKTRACEDEPTH; q++) { 393 char sym[KSYM_SYMBOL_LEN]; 394 char *c; 395 if (!task->latency_record[i].backtrace[q]) 396 break; 397 if (task->latency_record[i].backtrace[q] == ULONG_MAX) 398 break; 399 sprint_symbol(sym, task->latency_record[i].backtrace[q]); 400 c = strchr(sym, '+'); 401 if (c) 402 *c = 0; 403 seq_printf(m, "%s ", sym); 404 } 405 seq_printf(m, "\n"); 406 } 407 408 } 409 put_task_struct(task); 410 return 0; 411 } 412 413 static int lstats_open(struct inode *inode, struct file *file) 414 { 415 return single_open(file, lstats_show_proc, inode); 416 } 417 418 static ssize_t lstats_write(struct file *file, const char __user *buf, 419 size_t count, loff_t *offs) 420 { 421 struct task_struct *task = get_proc_task(file->f_dentry->d_inode); 422 423 if (!task) 424 return -ESRCH; 425 clear_all_latency_tracing(task); 426 put_task_struct(task); 427 428 return count; 429 } 430 431 static const struct file_operations proc_lstats_operations = { 432 .open = lstats_open, 433 .read = seq_read, 434 .write = lstats_write, 435 .llseek = seq_lseek, 436 .release = single_release, 437 }; 438 439 #endif 440 441 /* The badness from the OOM killer */ 442 unsigned long badness(struct task_struct *p, unsigned long uptime); 443 static int proc_oom_score(struct task_struct *task, char *buffer) 444 { 445 unsigned long points; 446 struct timespec uptime; 447 448 do_posix_clock_monotonic_gettime(&uptime); 449 read_lock(&tasklist_lock); 450 points = badness(task->group_leader, uptime.tv_sec); 451 read_unlock(&tasklist_lock); 452 return sprintf(buffer, "%lu\n", points); 453 } 454 455 struct limit_names { 456 char *name; 457 char *unit; 458 }; 459 460 static const struct limit_names lnames[RLIM_NLIMITS] = { 461 [RLIMIT_CPU] = {"Max cpu time", "seconds"}, 462 [RLIMIT_FSIZE] = {"Max file size", "bytes"}, 463 [RLIMIT_DATA] = {"Max data size", "bytes"}, 464 [RLIMIT_STACK] = {"Max stack size", "bytes"}, 465 [RLIMIT_CORE] = {"Max core file size", "bytes"}, 466 [RLIMIT_RSS] = {"Max resident set", "bytes"}, 467 [RLIMIT_NPROC] = {"Max processes", "processes"}, 468 [RLIMIT_NOFILE] = {"Max open files", "files"}, 469 [RLIMIT_MEMLOCK] = {"Max locked memory", "bytes"}, 470 [RLIMIT_AS] = {"Max address space", "bytes"}, 471 [RLIMIT_LOCKS] = {"Max file locks", "locks"}, 472 [RLIMIT_SIGPENDING] = {"Max pending signals", "signals"}, 473 [RLIMIT_MSGQUEUE] = {"Max msgqueue size", "bytes"}, 474 [RLIMIT_NICE] = {"Max nice priority", NULL}, 475 [RLIMIT_RTPRIO] = {"Max realtime priority", NULL}, 476 [RLIMIT_RTTIME] = {"Max realtime timeout", "us"}, 477 }; 478 479 /* Display limits for a process */ 480 static int proc_pid_limits(struct task_struct *task, char *buffer) 481 { 482 unsigned int i; 483 int count = 0; 484 unsigned long flags; 485 char *bufptr = buffer; 486 487 struct rlimit rlim[RLIM_NLIMITS]; 488 489 if (!lock_task_sighand(task, &flags)) 490 return 0; 491 memcpy(rlim, task->signal->rlim, sizeof(struct rlimit) * RLIM_NLIMITS); 492 unlock_task_sighand(task, &flags); 493 494 /* 495 * print the file header 496 */ 497 count += sprintf(&bufptr[count], "%-25s %-20s %-20s %-10s\n", 498 "Limit", "Soft Limit", "Hard Limit", "Units"); 499 500 for (i = 0; i < RLIM_NLIMITS; i++) { 501 if (rlim[i].rlim_cur == RLIM_INFINITY) 502 count += sprintf(&bufptr[count], "%-25s %-20s ", 503 lnames[i].name, "unlimited"); 504 else 505 count += sprintf(&bufptr[count], "%-25s %-20lu ", 506 lnames[i].name, rlim[i].rlim_cur); 507 508 if (rlim[i].rlim_max == RLIM_INFINITY) 509 count += sprintf(&bufptr[count], "%-20s ", "unlimited"); 510 else 511 count += sprintf(&bufptr[count], "%-20lu ", 512 rlim[i].rlim_max); 513 514 if (lnames[i].unit) 515 count += sprintf(&bufptr[count], "%-10s\n", 516 lnames[i].unit); 517 else 518 count += sprintf(&bufptr[count], "\n"); 519 } 520 521 return count; 522 } 523 524 #ifdef CONFIG_HAVE_ARCH_TRACEHOOK 525 static int proc_pid_syscall(struct task_struct *task, char *buffer) 526 { 527 long nr; 528 unsigned long args[6], sp, pc; 529 530 if (task_current_syscall(task, &nr, args, 6, &sp, &pc)) 531 return sprintf(buffer, "running\n"); 532 533 if (nr < 0) 534 return sprintf(buffer, "%ld 0x%lx 0x%lx\n", nr, sp, pc); 535 536 return sprintf(buffer, 537 "%ld 0x%lx 0x%lx 0x%lx 0x%lx 0x%lx 0x%lx 0x%lx 0x%lx\n", 538 nr, 539 args[0], args[1], args[2], args[3], args[4], args[5], 540 sp, pc); 541 } 542 #endif /* CONFIG_HAVE_ARCH_TRACEHOOK */ 543 544 /************************************************************************/ 545 /* Here the fs part begins */ 546 /************************************************************************/ 547 548 /* permission checks */ 549 static int proc_fd_access_allowed(struct inode *inode) 550 { 551 struct task_struct *task; 552 int allowed = 0; 553 /* Allow access to a task's file descriptors if it is us or we 554 * may use ptrace attach to the process and find out that 555 * information. 556 */ 557 task = get_proc_task(inode); 558 if (task) { 559 allowed = ptrace_may_access(task, PTRACE_MODE_READ); 560 put_task_struct(task); 561 } 562 return allowed; 563 } 564 565 static int proc_setattr(struct dentry *dentry, struct iattr *attr) 566 { 567 int error; 568 struct inode *inode = dentry->d_inode; 569 570 if (attr->ia_valid & ATTR_MODE) 571 return -EPERM; 572 573 error = inode_change_ok(inode, attr); 574 if (!error) 575 error = inode_setattr(inode, attr); 576 return error; 577 } 578 579 static const struct inode_operations proc_def_inode_operations = { 580 .setattr = proc_setattr, 581 }; 582 583 static int mounts_open_common(struct inode *inode, struct file *file, 584 const struct seq_operations *op) 585 { 586 struct task_struct *task = get_proc_task(inode); 587 struct nsproxy *nsp; 588 struct mnt_namespace *ns = NULL; 589 struct path root; 590 struct proc_mounts *p; 591 int ret = -EINVAL; 592 593 if (task) { 594 rcu_read_lock(); 595 nsp = task_nsproxy(task); 596 if (nsp) { 597 ns = nsp->mnt_ns; 598 if (ns) 599 get_mnt_ns(ns); 600 } 601 rcu_read_unlock(); 602 if (ns && get_fs_path(task, &root, 1) == 0) 603 ret = 0; 604 put_task_struct(task); 605 } 606 607 if (!ns) 608 goto err; 609 if (ret) 610 goto err_put_ns; 611 612 ret = -ENOMEM; 613 p = kmalloc(sizeof(struct proc_mounts), GFP_KERNEL); 614 if (!p) 615 goto err_put_path; 616 617 file->private_data = &p->m; 618 ret = seq_open(file, op); 619 if (ret) 620 goto err_free; 621 622 p->m.private = p; 623 p->ns = ns; 624 p->root = root; 625 p->event = ns->event; 626 627 return 0; 628 629 err_free: 630 kfree(p); 631 err_put_path: 632 path_put(&root); 633 err_put_ns: 634 put_mnt_ns(ns); 635 err: 636 return ret; 637 } 638 639 static int mounts_release(struct inode *inode, struct file *file) 640 { 641 struct proc_mounts *p = file->private_data; 642 path_put(&p->root); 643 put_mnt_ns(p->ns); 644 return seq_release(inode, file); 645 } 646 647 static unsigned mounts_poll(struct file *file, poll_table *wait) 648 { 649 struct proc_mounts *p = file->private_data; 650 unsigned res = POLLIN | POLLRDNORM; 651 652 poll_wait(file, &p->ns->poll, wait); 653 if (mnt_had_events(p)) 654 res |= POLLERR | POLLPRI; 655 656 return res; 657 } 658 659 static int mounts_open(struct inode *inode, struct file *file) 660 { 661 return mounts_open_common(inode, file, &mounts_op); 662 } 663 664 static const struct file_operations proc_mounts_operations = { 665 .open = mounts_open, 666 .read = seq_read, 667 .llseek = seq_lseek, 668 .release = mounts_release, 669 .poll = mounts_poll, 670 }; 671 672 static int mountinfo_open(struct inode *inode, struct file *file) 673 { 674 return mounts_open_common(inode, file, &mountinfo_op); 675 } 676 677 static const struct file_operations proc_mountinfo_operations = { 678 .open = mountinfo_open, 679 .read = seq_read, 680 .llseek = seq_lseek, 681 .release = mounts_release, 682 .poll = mounts_poll, 683 }; 684 685 static int mountstats_open(struct inode *inode, struct file *file) 686 { 687 return mounts_open_common(inode, file, &mountstats_op); 688 } 689 690 static const struct file_operations proc_mountstats_operations = { 691 .open = mountstats_open, 692 .read = seq_read, 693 .llseek = seq_lseek, 694 .release = mounts_release, 695 }; 696 697 #define PROC_BLOCK_SIZE (3*1024) /* 4K page size but our output routines use some slack for overruns */ 698 699 static ssize_t proc_info_read(struct file * file, char __user * buf, 700 size_t count, loff_t *ppos) 701 { 702 struct inode * inode = file->f_path.dentry->d_inode; 703 unsigned long page; 704 ssize_t length; 705 struct task_struct *task = get_proc_task(inode); 706 707 length = -ESRCH; 708 if (!task) 709 goto out_no_task; 710 711 if (count > PROC_BLOCK_SIZE) 712 count = PROC_BLOCK_SIZE; 713 714 length = -ENOMEM; 715 if (!(page = __get_free_page(GFP_TEMPORARY))) 716 goto out; 717 718 length = PROC_I(inode)->op.proc_read(task, (char*)page); 719 720 if (length >= 0) 721 length = simple_read_from_buffer(buf, count, ppos, (char *)page, length); 722 free_page(page); 723 out: 724 put_task_struct(task); 725 out_no_task: 726 return length; 727 } 728 729 static const struct file_operations proc_info_file_operations = { 730 .read = proc_info_read, 731 }; 732 733 static int proc_single_show(struct seq_file *m, void *v) 734 { 735 struct inode *inode = m->private; 736 struct pid_namespace *ns; 737 struct pid *pid; 738 struct task_struct *task; 739 int ret; 740 741 ns = inode->i_sb->s_fs_info; 742 pid = proc_pid(inode); 743 task = get_pid_task(pid, PIDTYPE_PID); 744 if (!task) 745 return -ESRCH; 746 747 ret = PROC_I(inode)->op.proc_show(m, ns, pid, task); 748 749 put_task_struct(task); 750 return ret; 751 } 752 753 static int proc_single_open(struct inode *inode, struct file *filp) 754 { 755 int ret; 756 ret = single_open(filp, proc_single_show, NULL); 757 if (!ret) { 758 struct seq_file *m = filp->private_data; 759 760 m->private = inode; 761 } 762 return ret; 763 } 764 765 static const struct file_operations proc_single_file_operations = { 766 .open = proc_single_open, 767 .read = seq_read, 768 .llseek = seq_lseek, 769 .release = single_release, 770 }; 771 772 static int mem_open(struct inode* inode, struct file* file) 773 { 774 file->private_data = (void*)((long)current->self_exec_id); 775 return 0; 776 } 777 778 static ssize_t mem_read(struct file * file, char __user * buf, 779 size_t count, loff_t *ppos) 780 { 781 struct task_struct *task = get_proc_task(file->f_path.dentry->d_inode); 782 char *page; 783 unsigned long src = *ppos; 784 int ret = -ESRCH; 785 struct mm_struct *mm; 786 787 if (!task) 788 goto out_no_task; 789 790 if (check_mem_permission(task)) 791 goto out; 792 793 ret = -ENOMEM; 794 page = (char *)__get_free_page(GFP_TEMPORARY); 795 if (!page) 796 goto out; 797 798 ret = 0; 799 800 mm = get_task_mm(task); 801 if (!mm) 802 goto out_free; 803 804 ret = -EIO; 805 806 if (file->private_data != (void*)((long)current->self_exec_id)) 807 goto out_put; 808 809 ret = 0; 810 811 while (count > 0) { 812 int this_len, retval; 813 814 this_len = (count > PAGE_SIZE) ? PAGE_SIZE : count; 815 retval = access_process_vm(task, src, page, this_len, 0); 816 if (!retval || check_mem_permission(task)) { 817 if (!ret) 818 ret = -EIO; 819 break; 820 } 821 822 if (copy_to_user(buf, page, retval)) { 823 ret = -EFAULT; 824 break; 825 } 826 827 ret += retval; 828 src += retval; 829 buf += retval; 830 count -= retval; 831 } 832 *ppos = src; 833 834 out_put: 835 mmput(mm); 836 out_free: 837 free_page((unsigned long) page); 838 out: 839 put_task_struct(task); 840 out_no_task: 841 return ret; 842 } 843 844 #define mem_write NULL 845 846 #ifndef mem_write 847 /* This is a security hazard */ 848 static ssize_t mem_write(struct file * file, const char __user *buf, 849 size_t count, loff_t *ppos) 850 { 851 int copied; 852 char *page; 853 struct task_struct *task = get_proc_task(file->f_path.dentry->d_inode); 854 unsigned long dst = *ppos; 855 856 copied = -ESRCH; 857 if (!task) 858 goto out_no_task; 859 860 if (check_mem_permission(task)) 861 goto out; 862 863 copied = -ENOMEM; 864 page = (char *)__get_free_page(GFP_TEMPORARY); 865 if (!page) 866 goto out; 867 868 copied = 0; 869 while (count > 0) { 870 int this_len, retval; 871 872 this_len = (count > PAGE_SIZE) ? PAGE_SIZE : count; 873 if (copy_from_user(page, buf, this_len)) { 874 copied = -EFAULT; 875 break; 876 } 877 retval = access_process_vm(task, dst, page, this_len, 1); 878 if (!retval) { 879 if (!copied) 880 copied = -EIO; 881 break; 882 } 883 copied += retval; 884 buf += retval; 885 dst += retval; 886 count -= retval; 887 } 888 *ppos = dst; 889 free_page((unsigned long) page); 890 out: 891 put_task_struct(task); 892 out_no_task: 893 return copied; 894 } 895 #endif 896 897 loff_t mem_lseek(struct file *file, loff_t offset, int orig) 898 { 899 switch (orig) { 900 case 0: 901 file->f_pos = offset; 902 break; 903 case 1: 904 file->f_pos += offset; 905 break; 906 default: 907 return -EINVAL; 908 } 909 force_successful_syscall_return(); 910 return file->f_pos; 911 } 912 913 static const struct file_operations proc_mem_operations = { 914 .llseek = mem_lseek, 915 .read = mem_read, 916 .write = mem_write, 917 .open = mem_open, 918 }; 919 920 static ssize_t environ_read(struct file *file, char __user *buf, 921 size_t count, loff_t *ppos) 922 { 923 struct task_struct *task = get_proc_task(file->f_dentry->d_inode); 924 char *page; 925 unsigned long src = *ppos; 926 int ret = -ESRCH; 927 struct mm_struct *mm; 928 929 if (!task) 930 goto out_no_task; 931 932 if (!ptrace_may_access(task, PTRACE_MODE_READ)) 933 goto out; 934 935 ret = -ENOMEM; 936 page = (char *)__get_free_page(GFP_TEMPORARY); 937 if (!page) 938 goto out; 939 940 ret = 0; 941 942 mm = get_task_mm(task); 943 if (!mm) 944 goto out_free; 945 946 while (count > 0) { 947 int this_len, retval, max_len; 948 949 this_len = mm->env_end - (mm->env_start + src); 950 951 if (this_len <= 0) 952 break; 953 954 max_len = (count > PAGE_SIZE) ? PAGE_SIZE : count; 955 this_len = (this_len > max_len) ? max_len : this_len; 956 957 retval = access_process_vm(task, (mm->env_start + src), 958 page, this_len, 0); 959 960 if (retval <= 0) { 961 ret = retval; 962 break; 963 } 964 965 if (copy_to_user(buf, page, retval)) { 966 ret = -EFAULT; 967 break; 968 } 969 970 ret += retval; 971 src += retval; 972 buf += retval; 973 count -= retval; 974 } 975 *ppos = src; 976 977 mmput(mm); 978 out_free: 979 free_page((unsigned long) page); 980 out: 981 put_task_struct(task); 982 out_no_task: 983 return ret; 984 } 985 986 static const struct file_operations proc_environ_operations = { 987 .read = environ_read, 988 }; 989 990 static ssize_t oom_adjust_read(struct file *file, char __user *buf, 991 size_t count, loff_t *ppos) 992 { 993 struct task_struct *task = get_proc_task(file->f_path.dentry->d_inode); 994 char buffer[PROC_NUMBUF]; 995 size_t len; 996 int oom_adjust = OOM_DISABLE; 997 unsigned long flags; 998 999 if (!task) 1000 return -ESRCH; 1001 1002 if (lock_task_sighand(task, &flags)) { 1003 oom_adjust = task->signal->oom_adj; 1004 unlock_task_sighand(task, &flags); 1005 } 1006 1007 put_task_struct(task); 1008 1009 len = snprintf(buffer, sizeof(buffer), "%i\n", oom_adjust); 1010 1011 return simple_read_from_buffer(buf, count, ppos, buffer, len); 1012 } 1013 1014 static ssize_t oom_adjust_write(struct file *file, const char __user *buf, 1015 size_t count, loff_t *ppos) 1016 { 1017 struct task_struct *task; 1018 char buffer[PROC_NUMBUF]; 1019 long oom_adjust; 1020 unsigned long flags; 1021 int err; 1022 1023 memset(buffer, 0, sizeof(buffer)); 1024 if (count > sizeof(buffer) - 1) 1025 count = sizeof(buffer) - 1; 1026 if (copy_from_user(buffer, buf, count)) 1027 return -EFAULT; 1028 1029 err = strict_strtol(strstrip(buffer), 0, &oom_adjust); 1030 if (err) 1031 return -EINVAL; 1032 if ((oom_adjust < OOM_ADJUST_MIN || oom_adjust > OOM_ADJUST_MAX) && 1033 oom_adjust != OOM_DISABLE) 1034 return -EINVAL; 1035 1036 task = get_proc_task(file->f_path.dentry->d_inode); 1037 if (!task) 1038 return -ESRCH; 1039 if (!lock_task_sighand(task, &flags)) { 1040 put_task_struct(task); 1041 return -ESRCH; 1042 } 1043 1044 if (oom_adjust < task->signal->oom_adj && !capable(CAP_SYS_RESOURCE)) { 1045 unlock_task_sighand(task, &flags); 1046 put_task_struct(task); 1047 return -EACCES; 1048 } 1049 1050 task->signal->oom_adj = oom_adjust; 1051 1052 unlock_task_sighand(task, &flags); 1053 put_task_struct(task); 1054 1055 return count; 1056 } 1057 1058 static const struct file_operations proc_oom_adjust_operations = { 1059 .read = oom_adjust_read, 1060 .write = oom_adjust_write, 1061 }; 1062 1063 #ifdef CONFIG_AUDITSYSCALL 1064 #define TMPBUFLEN 21 1065 static ssize_t proc_loginuid_read(struct file * file, char __user * buf, 1066 size_t count, loff_t *ppos) 1067 { 1068 struct inode * inode = file->f_path.dentry->d_inode; 1069 struct task_struct *task = get_proc_task(inode); 1070 ssize_t length; 1071 char tmpbuf[TMPBUFLEN]; 1072 1073 if (!task) 1074 return -ESRCH; 1075 length = scnprintf(tmpbuf, TMPBUFLEN, "%u", 1076 audit_get_loginuid(task)); 1077 put_task_struct(task); 1078 return simple_read_from_buffer(buf, count, ppos, tmpbuf, length); 1079 } 1080 1081 static ssize_t proc_loginuid_write(struct file * file, const char __user * buf, 1082 size_t count, loff_t *ppos) 1083 { 1084 struct inode * inode = file->f_path.dentry->d_inode; 1085 char *page, *tmp; 1086 ssize_t length; 1087 uid_t loginuid; 1088 1089 if (!capable(CAP_AUDIT_CONTROL)) 1090 return -EPERM; 1091 1092 rcu_read_lock(); 1093 if (current != pid_task(proc_pid(inode), PIDTYPE_PID)) { 1094 rcu_read_unlock(); 1095 return -EPERM; 1096 } 1097 rcu_read_unlock(); 1098 1099 if (count >= PAGE_SIZE) 1100 count = PAGE_SIZE - 1; 1101 1102 if (*ppos != 0) { 1103 /* No partial writes. */ 1104 return -EINVAL; 1105 } 1106 page = (char*)__get_free_page(GFP_TEMPORARY); 1107 if (!page) 1108 return -ENOMEM; 1109 length = -EFAULT; 1110 if (copy_from_user(page, buf, count)) 1111 goto out_free_page; 1112 1113 page[count] = '\0'; 1114 loginuid = simple_strtoul(page, &tmp, 10); 1115 if (tmp == page) { 1116 length = -EINVAL; 1117 goto out_free_page; 1118 1119 } 1120 length = audit_set_loginuid(current, loginuid); 1121 if (likely(length == 0)) 1122 length = count; 1123 1124 out_free_page: 1125 free_page((unsigned long) page); 1126 return length; 1127 } 1128 1129 static const struct file_operations proc_loginuid_operations = { 1130 .read = proc_loginuid_read, 1131 .write = proc_loginuid_write, 1132 }; 1133 1134 static ssize_t proc_sessionid_read(struct file * file, char __user * buf, 1135 size_t count, loff_t *ppos) 1136 { 1137 struct inode * inode = file->f_path.dentry->d_inode; 1138 struct task_struct *task = get_proc_task(inode); 1139 ssize_t length; 1140 char tmpbuf[TMPBUFLEN]; 1141 1142 if (!task) 1143 return -ESRCH; 1144 length = scnprintf(tmpbuf, TMPBUFLEN, "%u", 1145 audit_get_sessionid(task)); 1146 put_task_struct(task); 1147 return simple_read_from_buffer(buf, count, ppos, tmpbuf, length); 1148 } 1149 1150 static const struct file_operations proc_sessionid_operations = { 1151 .read = proc_sessionid_read, 1152 }; 1153 #endif 1154 1155 #ifdef CONFIG_FAULT_INJECTION 1156 static ssize_t proc_fault_inject_read(struct file * file, char __user * buf, 1157 size_t count, loff_t *ppos) 1158 { 1159 struct task_struct *task = get_proc_task(file->f_dentry->d_inode); 1160 char buffer[PROC_NUMBUF]; 1161 size_t len; 1162 int make_it_fail; 1163 1164 if (!task) 1165 return -ESRCH; 1166 make_it_fail = task->make_it_fail; 1167 put_task_struct(task); 1168 1169 len = snprintf(buffer, sizeof(buffer), "%i\n", make_it_fail); 1170 1171 return simple_read_from_buffer(buf, count, ppos, buffer, len); 1172 } 1173 1174 static ssize_t proc_fault_inject_write(struct file * file, 1175 const char __user * buf, size_t count, loff_t *ppos) 1176 { 1177 struct task_struct *task; 1178 char buffer[PROC_NUMBUF], *end; 1179 int make_it_fail; 1180 1181 if (!capable(CAP_SYS_RESOURCE)) 1182 return -EPERM; 1183 memset(buffer, 0, sizeof(buffer)); 1184 if (count > sizeof(buffer) - 1) 1185 count = sizeof(buffer) - 1; 1186 if (copy_from_user(buffer, buf, count)) 1187 return -EFAULT; 1188 make_it_fail = simple_strtol(strstrip(buffer), &end, 0); 1189 if (*end) 1190 return -EINVAL; 1191 task = get_proc_task(file->f_dentry->d_inode); 1192 if (!task) 1193 return -ESRCH; 1194 task->make_it_fail = make_it_fail; 1195 put_task_struct(task); 1196 1197 return count; 1198 } 1199 1200 static const struct file_operations proc_fault_inject_operations = { 1201 .read = proc_fault_inject_read, 1202 .write = proc_fault_inject_write, 1203 }; 1204 #endif 1205 1206 1207 #ifdef CONFIG_SCHED_DEBUG 1208 /* 1209 * Print out various scheduling related per-task fields: 1210 */ 1211 static int sched_show(struct seq_file *m, void *v) 1212 { 1213 struct inode *inode = m->private; 1214 struct task_struct *p; 1215 1216 p = get_proc_task(inode); 1217 if (!p) 1218 return -ESRCH; 1219 proc_sched_show_task(p, m); 1220 1221 put_task_struct(p); 1222 1223 return 0; 1224 } 1225 1226 static ssize_t 1227 sched_write(struct file *file, const char __user *buf, 1228 size_t count, loff_t *offset) 1229 { 1230 struct inode *inode = file->f_path.dentry->d_inode; 1231 struct task_struct *p; 1232 1233 p = get_proc_task(inode); 1234 if (!p) 1235 return -ESRCH; 1236 proc_sched_set_task(p); 1237 1238 put_task_struct(p); 1239 1240 return count; 1241 } 1242 1243 static int sched_open(struct inode *inode, struct file *filp) 1244 { 1245 int ret; 1246 1247 ret = single_open(filp, sched_show, NULL); 1248 if (!ret) { 1249 struct seq_file *m = filp->private_data; 1250 1251 m->private = inode; 1252 } 1253 return ret; 1254 } 1255 1256 static const struct file_operations proc_pid_sched_operations = { 1257 .open = sched_open, 1258 .read = seq_read, 1259 .write = sched_write, 1260 .llseek = seq_lseek, 1261 .release = single_release, 1262 }; 1263 1264 #endif 1265 1266 static ssize_t comm_write(struct file *file, const char __user *buf, 1267 size_t count, loff_t *offset) 1268 { 1269 struct inode *inode = file->f_path.dentry->d_inode; 1270 struct task_struct *p; 1271 char buffer[TASK_COMM_LEN]; 1272 1273 memset(buffer, 0, sizeof(buffer)); 1274 if (count > sizeof(buffer) - 1) 1275 count = sizeof(buffer) - 1; 1276 if (copy_from_user(buffer, buf, count)) 1277 return -EFAULT; 1278 1279 p = get_proc_task(inode); 1280 if (!p) 1281 return -ESRCH; 1282 1283 if (same_thread_group(current, p)) 1284 set_task_comm(p, buffer); 1285 else 1286 count = -EINVAL; 1287 1288 put_task_struct(p); 1289 1290 return count; 1291 } 1292 1293 static int comm_show(struct seq_file *m, void *v) 1294 { 1295 struct inode *inode = m->private; 1296 struct task_struct *p; 1297 1298 p = get_proc_task(inode); 1299 if (!p) 1300 return -ESRCH; 1301 1302 task_lock(p); 1303 seq_printf(m, "%s\n", p->comm); 1304 task_unlock(p); 1305 1306 put_task_struct(p); 1307 1308 return 0; 1309 } 1310 1311 static int comm_open(struct inode *inode, struct file *filp) 1312 { 1313 int ret; 1314 1315 ret = single_open(filp, comm_show, NULL); 1316 if (!ret) { 1317 struct seq_file *m = filp->private_data; 1318 1319 m->private = inode; 1320 } 1321 return ret; 1322 } 1323 1324 static const struct file_operations proc_pid_set_comm_operations = { 1325 .open = comm_open, 1326 .read = seq_read, 1327 .write = comm_write, 1328 .llseek = seq_lseek, 1329 .release = single_release, 1330 }; 1331 1332 /* 1333 * We added or removed a vma mapping the executable. The vmas are only mapped 1334 * during exec and are not mapped with the mmap system call. 1335 * Callers must hold down_write() on the mm's mmap_sem for these 1336 */ 1337 void added_exe_file_vma(struct mm_struct *mm) 1338 { 1339 mm->num_exe_file_vmas++; 1340 } 1341 1342 void removed_exe_file_vma(struct mm_struct *mm) 1343 { 1344 mm->num_exe_file_vmas--; 1345 if ((mm->num_exe_file_vmas == 0) && mm->exe_file){ 1346 fput(mm->exe_file); 1347 mm->exe_file = NULL; 1348 } 1349 1350 } 1351 1352 void set_mm_exe_file(struct mm_struct *mm, struct file *new_exe_file) 1353 { 1354 if (new_exe_file) 1355 get_file(new_exe_file); 1356 if (mm->exe_file) 1357 fput(mm->exe_file); 1358 mm->exe_file = new_exe_file; 1359 mm->num_exe_file_vmas = 0; 1360 } 1361 1362 struct file *get_mm_exe_file(struct mm_struct *mm) 1363 { 1364 struct file *exe_file; 1365 1366 /* We need mmap_sem to protect against races with removal of 1367 * VM_EXECUTABLE vmas */ 1368 down_read(&mm->mmap_sem); 1369 exe_file = mm->exe_file; 1370 if (exe_file) 1371 get_file(exe_file); 1372 up_read(&mm->mmap_sem); 1373 return exe_file; 1374 } 1375 1376 void dup_mm_exe_file(struct mm_struct *oldmm, struct mm_struct *newmm) 1377 { 1378 /* It's safe to write the exe_file pointer without exe_file_lock because 1379 * this is called during fork when the task is not yet in /proc */ 1380 newmm->exe_file = get_mm_exe_file(oldmm); 1381 } 1382 1383 static int proc_exe_link(struct inode *inode, struct path *exe_path) 1384 { 1385 struct task_struct *task; 1386 struct mm_struct *mm; 1387 struct file *exe_file; 1388 1389 task = get_proc_task(inode); 1390 if (!task) 1391 return -ENOENT; 1392 mm = get_task_mm(task); 1393 put_task_struct(task); 1394 if (!mm) 1395 return -ENOENT; 1396 exe_file = get_mm_exe_file(mm); 1397 mmput(mm); 1398 if (exe_file) { 1399 *exe_path = exe_file->f_path; 1400 path_get(&exe_file->f_path); 1401 fput(exe_file); 1402 return 0; 1403 } else 1404 return -ENOENT; 1405 } 1406 1407 static void *proc_pid_follow_link(struct dentry *dentry, struct nameidata *nd) 1408 { 1409 struct inode *inode = dentry->d_inode; 1410 int error = -EACCES; 1411 1412 /* We don't need a base pointer in the /proc filesystem */ 1413 path_put(&nd->path); 1414 1415 /* Are we allowed to snoop on the tasks file descriptors? */ 1416 if (!proc_fd_access_allowed(inode)) 1417 goto out; 1418 1419 error = PROC_I(inode)->op.proc_get_link(inode, &nd->path); 1420 out: 1421 return ERR_PTR(error); 1422 } 1423 1424 static int do_proc_readlink(struct path *path, char __user *buffer, int buflen) 1425 { 1426 char *tmp = (char*)__get_free_page(GFP_TEMPORARY); 1427 char *pathname; 1428 int len; 1429 1430 if (!tmp) 1431 return -ENOMEM; 1432 1433 pathname = d_path(path, tmp, PAGE_SIZE); 1434 len = PTR_ERR(pathname); 1435 if (IS_ERR(pathname)) 1436 goto out; 1437 len = tmp + PAGE_SIZE - 1 - pathname; 1438 1439 if (len > buflen) 1440 len = buflen; 1441 if (copy_to_user(buffer, pathname, len)) 1442 len = -EFAULT; 1443 out: 1444 free_page((unsigned long)tmp); 1445 return len; 1446 } 1447 1448 static int proc_pid_readlink(struct dentry * dentry, char __user * buffer, int buflen) 1449 { 1450 int error = -EACCES; 1451 struct inode *inode = dentry->d_inode; 1452 struct path path; 1453 1454 /* Are we allowed to snoop on the tasks file descriptors? */ 1455 if (!proc_fd_access_allowed(inode)) 1456 goto out; 1457 1458 error = PROC_I(inode)->op.proc_get_link(inode, &path); 1459 if (error) 1460 goto out; 1461 1462 error = do_proc_readlink(&path, buffer, buflen); 1463 path_put(&path); 1464 out: 1465 return error; 1466 } 1467 1468 static const struct inode_operations proc_pid_link_inode_operations = { 1469 .readlink = proc_pid_readlink, 1470 .follow_link = proc_pid_follow_link, 1471 .setattr = proc_setattr, 1472 }; 1473 1474 1475 /* building an inode */ 1476 1477 static int task_dumpable(struct task_struct *task) 1478 { 1479 int dumpable = 0; 1480 struct mm_struct *mm; 1481 1482 task_lock(task); 1483 mm = task->mm; 1484 if (mm) 1485 dumpable = get_dumpable(mm); 1486 task_unlock(task); 1487 if(dumpable == 1) 1488 return 1; 1489 return 0; 1490 } 1491 1492 1493 static struct inode *proc_pid_make_inode(struct super_block * sb, struct task_struct *task) 1494 { 1495 struct inode * inode; 1496 struct proc_inode *ei; 1497 const struct cred *cred; 1498 1499 /* We need a new inode */ 1500 1501 inode = new_inode(sb); 1502 if (!inode) 1503 goto out; 1504 1505 /* Common stuff */ 1506 ei = PROC_I(inode); 1507 inode->i_mtime = inode->i_atime = inode->i_ctime = CURRENT_TIME; 1508 inode->i_op = &proc_def_inode_operations; 1509 1510 /* 1511 * grab the reference to task. 1512 */ 1513 ei->pid = get_task_pid(task, PIDTYPE_PID); 1514 if (!ei->pid) 1515 goto out_unlock; 1516 1517 if (task_dumpable(task)) { 1518 rcu_read_lock(); 1519 cred = __task_cred(task); 1520 inode->i_uid = cred->euid; 1521 inode->i_gid = cred->egid; 1522 rcu_read_unlock(); 1523 } 1524 security_task_to_inode(task, inode); 1525 1526 out: 1527 return inode; 1528 1529 out_unlock: 1530 iput(inode); 1531 return NULL; 1532 } 1533 1534 static int pid_getattr(struct vfsmount *mnt, struct dentry *dentry, struct kstat *stat) 1535 { 1536 struct inode *inode = dentry->d_inode; 1537 struct task_struct *task; 1538 const struct cred *cred; 1539 1540 generic_fillattr(inode, stat); 1541 1542 rcu_read_lock(); 1543 stat->uid = 0; 1544 stat->gid = 0; 1545 task = pid_task(proc_pid(inode), PIDTYPE_PID); 1546 if (task) { 1547 if ((inode->i_mode == (S_IFDIR|S_IRUGO|S_IXUGO)) || 1548 task_dumpable(task)) { 1549 cred = __task_cred(task); 1550 stat->uid = cred->euid; 1551 stat->gid = cred->egid; 1552 } 1553 } 1554 rcu_read_unlock(); 1555 return 0; 1556 } 1557 1558 /* dentry stuff */ 1559 1560 /* 1561 * Exceptional case: normally we are not allowed to unhash a busy 1562 * directory. In this case, however, we can do it - no aliasing problems 1563 * due to the way we treat inodes. 1564 * 1565 * Rewrite the inode's ownerships here because the owning task may have 1566 * performed a setuid(), etc. 1567 * 1568 * Before the /proc/pid/status file was created the only way to read 1569 * the effective uid of a /process was to stat /proc/pid. Reading 1570 * /proc/pid/status is slow enough that procps and other packages 1571 * kept stating /proc/pid. To keep the rules in /proc simple I have 1572 * made this apply to all per process world readable and executable 1573 * directories. 1574 */ 1575 static int pid_revalidate(struct dentry *dentry, struct nameidata *nd) 1576 { 1577 struct inode *inode = dentry->d_inode; 1578 struct task_struct *task = get_proc_task(inode); 1579 const struct cred *cred; 1580 1581 if (task) { 1582 if ((inode->i_mode == (S_IFDIR|S_IRUGO|S_IXUGO)) || 1583 task_dumpable(task)) { 1584 rcu_read_lock(); 1585 cred = __task_cred(task); 1586 inode->i_uid = cred->euid; 1587 inode->i_gid = cred->egid; 1588 rcu_read_unlock(); 1589 } else { 1590 inode->i_uid = 0; 1591 inode->i_gid = 0; 1592 } 1593 inode->i_mode &= ~(S_ISUID | S_ISGID); 1594 security_task_to_inode(task, inode); 1595 put_task_struct(task); 1596 return 1; 1597 } 1598 d_drop(dentry); 1599 return 0; 1600 } 1601 1602 static int pid_delete_dentry(struct dentry * dentry) 1603 { 1604 /* Is the task we represent dead? 1605 * If so, then don't put the dentry on the lru list, 1606 * kill it immediately. 1607 */ 1608 return !proc_pid(dentry->d_inode)->tasks[PIDTYPE_PID].first; 1609 } 1610 1611 static const struct dentry_operations pid_dentry_operations = 1612 { 1613 .d_revalidate = pid_revalidate, 1614 .d_delete = pid_delete_dentry, 1615 }; 1616 1617 /* Lookups */ 1618 1619 typedef struct dentry *instantiate_t(struct inode *, struct dentry *, 1620 struct task_struct *, const void *); 1621 1622 /* 1623 * Fill a directory entry. 1624 * 1625 * If possible create the dcache entry and derive our inode number and 1626 * file type from dcache entry. 1627 * 1628 * Since all of the proc inode numbers are dynamically generated, the inode 1629 * numbers do not exist until the inode is cache. This means creating the 1630 * the dcache entry in readdir is necessary to keep the inode numbers 1631 * reported by readdir in sync with the inode numbers reported 1632 * by stat. 1633 */ 1634 static int proc_fill_cache(struct file *filp, void *dirent, filldir_t filldir, 1635 char *name, int len, 1636 instantiate_t instantiate, struct task_struct *task, const void *ptr) 1637 { 1638 struct dentry *child, *dir = filp->f_path.dentry; 1639 struct inode *inode; 1640 struct qstr qname; 1641 ino_t ino = 0; 1642 unsigned type = DT_UNKNOWN; 1643 1644 qname.name = name; 1645 qname.len = len; 1646 qname.hash = full_name_hash(name, len); 1647 1648 child = d_lookup(dir, &qname); 1649 if (!child) { 1650 struct dentry *new; 1651 new = d_alloc(dir, &qname); 1652 if (new) { 1653 child = instantiate(dir->d_inode, new, task, ptr); 1654 if (child) 1655 dput(new); 1656 else 1657 child = new; 1658 } 1659 } 1660 if (!child || IS_ERR(child) || !child->d_inode) 1661 goto end_instantiate; 1662 inode = child->d_inode; 1663 if (inode) { 1664 ino = inode->i_ino; 1665 type = inode->i_mode >> 12; 1666 } 1667 dput(child); 1668 end_instantiate: 1669 if (!ino) 1670 ino = find_inode_number(dir, &qname); 1671 if (!ino) 1672 ino = 1; 1673 return filldir(dirent, name, len, filp->f_pos, ino, type); 1674 } 1675 1676 static unsigned name_to_int(struct dentry *dentry) 1677 { 1678 const char *name = dentry->d_name.name; 1679 int len = dentry->d_name.len; 1680 unsigned n = 0; 1681 1682 if (len > 1 && *name == '0') 1683 goto out; 1684 while (len-- > 0) { 1685 unsigned c = *name++ - '0'; 1686 if (c > 9) 1687 goto out; 1688 if (n >= (~0U-9)/10) 1689 goto out; 1690 n *= 10; 1691 n += c; 1692 } 1693 return n; 1694 out: 1695 return ~0U; 1696 } 1697 1698 #define PROC_FDINFO_MAX 64 1699 1700 static int proc_fd_info(struct inode *inode, struct path *path, char *info) 1701 { 1702 struct task_struct *task = get_proc_task(inode); 1703 struct files_struct *files = NULL; 1704 struct file *file; 1705 int fd = proc_fd(inode); 1706 1707 if (task) { 1708 files = get_files_struct(task); 1709 put_task_struct(task); 1710 } 1711 if (files) { 1712 /* 1713 * We are not taking a ref to the file structure, so we must 1714 * hold ->file_lock. 1715 */ 1716 spin_lock(&files->file_lock); 1717 file = fcheck_files(files, fd); 1718 if (file) { 1719 if (path) { 1720 *path = file->f_path; 1721 path_get(&file->f_path); 1722 } 1723 if (info) 1724 snprintf(info, PROC_FDINFO_MAX, 1725 "pos:\t%lli\n" 1726 "flags:\t0%o\n", 1727 (long long) file->f_pos, 1728 file->f_flags); 1729 spin_unlock(&files->file_lock); 1730 put_files_struct(files); 1731 return 0; 1732 } 1733 spin_unlock(&files->file_lock); 1734 put_files_struct(files); 1735 } 1736 return -ENOENT; 1737 } 1738 1739 static int proc_fd_link(struct inode *inode, struct path *path) 1740 { 1741 return proc_fd_info(inode, path, NULL); 1742 } 1743 1744 static int tid_fd_revalidate(struct dentry *dentry, struct nameidata *nd) 1745 { 1746 struct inode *inode = dentry->d_inode; 1747 struct task_struct *task = get_proc_task(inode); 1748 int fd = proc_fd(inode); 1749 struct files_struct *files; 1750 const struct cred *cred; 1751 1752 if (task) { 1753 files = get_files_struct(task); 1754 if (files) { 1755 rcu_read_lock(); 1756 if (fcheck_files(files, fd)) { 1757 rcu_read_unlock(); 1758 put_files_struct(files); 1759 if (task_dumpable(task)) { 1760 rcu_read_lock(); 1761 cred = __task_cred(task); 1762 inode->i_uid = cred->euid; 1763 inode->i_gid = cred->egid; 1764 rcu_read_unlock(); 1765 } else { 1766 inode->i_uid = 0; 1767 inode->i_gid = 0; 1768 } 1769 inode->i_mode &= ~(S_ISUID | S_ISGID); 1770 security_task_to_inode(task, inode); 1771 put_task_struct(task); 1772 return 1; 1773 } 1774 rcu_read_unlock(); 1775 put_files_struct(files); 1776 } 1777 put_task_struct(task); 1778 } 1779 d_drop(dentry); 1780 return 0; 1781 } 1782 1783 static const struct dentry_operations tid_fd_dentry_operations = 1784 { 1785 .d_revalidate = tid_fd_revalidate, 1786 .d_delete = pid_delete_dentry, 1787 }; 1788 1789 static struct dentry *proc_fd_instantiate(struct inode *dir, 1790 struct dentry *dentry, struct task_struct *task, const void *ptr) 1791 { 1792 unsigned fd = *(const unsigned *)ptr; 1793 struct file *file; 1794 struct files_struct *files; 1795 struct inode *inode; 1796 struct proc_inode *ei; 1797 struct dentry *error = ERR_PTR(-ENOENT); 1798 1799 inode = proc_pid_make_inode(dir->i_sb, task); 1800 if (!inode) 1801 goto out; 1802 ei = PROC_I(inode); 1803 ei->fd = fd; 1804 files = get_files_struct(task); 1805 if (!files) 1806 goto out_iput; 1807 inode->i_mode = S_IFLNK; 1808 1809 /* 1810 * We are not taking a ref to the file structure, so we must 1811 * hold ->file_lock. 1812 */ 1813 spin_lock(&files->file_lock); 1814 file = fcheck_files(files, fd); 1815 if (!file) 1816 goto out_unlock; 1817 if (file->f_mode & FMODE_READ) 1818 inode->i_mode |= S_IRUSR | S_IXUSR; 1819 if (file->f_mode & FMODE_WRITE) 1820 inode->i_mode |= S_IWUSR | S_IXUSR; 1821 spin_unlock(&files->file_lock); 1822 put_files_struct(files); 1823 1824 inode->i_op = &proc_pid_link_inode_operations; 1825 inode->i_size = 64; 1826 ei->op.proc_get_link = proc_fd_link; 1827 dentry->d_op = &tid_fd_dentry_operations; 1828 d_add(dentry, inode); 1829 /* Close the race of the process dying before we return the dentry */ 1830 if (tid_fd_revalidate(dentry, NULL)) 1831 error = NULL; 1832 1833 out: 1834 return error; 1835 out_unlock: 1836 spin_unlock(&files->file_lock); 1837 put_files_struct(files); 1838 out_iput: 1839 iput(inode); 1840 goto out; 1841 } 1842 1843 static struct dentry *proc_lookupfd_common(struct inode *dir, 1844 struct dentry *dentry, 1845 instantiate_t instantiate) 1846 { 1847 struct task_struct *task = get_proc_task(dir); 1848 unsigned fd = name_to_int(dentry); 1849 struct dentry *result = ERR_PTR(-ENOENT); 1850 1851 if (!task) 1852 goto out_no_task; 1853 if (fd == ~0U) 1854 goto out; 1855 1856 result = instantiate(dir, dentry, task, &fd); 1857 out: 1858 put_task_struct(task); 1859 out_no_task: 1860 return result; 1861 } 1862 1863 static int proc_readfd_common(struct file * filp, void * dirent, 1864 filldir_t filldir, instantiate_t instantiate) 1865 { 1866 struct dentry *dentry = filp->f_path.dentry; 1867 struct inode *inode = dentry->d_inode; 1868 struct task_struct *p = get_proc_task(inode); 1869 unsigned int fd, ino; 1870 int retval; 1871 struct files_struct * files; 1872 1873 retval = -ENOENT; 1874 if (!p) 1875 goto out_no_task; 1876 retval = 0; 1877 1878 fd = filp->f_pos; 1879 switch (fd) { 1880 case 0: 1881 if (filldir(dirent, ".", 1, 0, inode->i_ino, DT_DIR) < 0) 1882 goto out; 1883 filp->f_pos++; 1884 case 1: 1885 ino = parent_ino(dentry); 1886 if (filldir(dirent, "..", 2, 1, ino, DT_DIR) < 0) 1887 goto out; 1888 filp->f_pos++; 1889 default: 1890 files = get_files_struct(p); 1891 if (!files) 1892 goto out; 1893 rcu_read_lock(); 1894 for (fd = filp->f_pos-2; 1895 fd < files_fdtable(files)->max_fds; 1896 fd++, filp->f_pos++) { 1897 char name[PROC_NUMBUF]; 1898 int len; 1899 1900 if (!fcheck_files(files, fd)) 1901 continue; 1902 rcu_read_unlock(); 1903 1904 len = snprintf(name, sizeof(name), "%d", fd); 1905 if (proc_fill_cache(filp, dirent, filldir, 1906 name, len, instantiate, 1907 p, &fd) < 0) { 1908 rcu_read_lock(); 1909 break; 1910 } 1911 rcu_read_lock(); 1912 } 1913 rcu_read_unlock(); 1914 put_files_struct(files); 1915 } 1916 out: 1917 put_task_struct(p); 1918 out_no_task: 1919 return retval; 1920 } 1921 1922 static struct dentry *proc_lookupfd(struct inode *dir, struct dentry *dentry, 1923 struct nameidata *nd) 1924 { 1925 return proc_lookupfd_common(dir, dentry, proc_fd_instantiate); 1926 } 1927 1928 static int proc_readfd(struct file *filp, void *dirent, filldir_t filldir) 1929 { 1930 return proc_readfd_common(filp, dirent, filldir, proc_fd_instantiate); 1931 } 1932 1933 static ssize_t proc_fdinfo_read(struct file *file, char __user *buf, 1934 size_t len, loff_t *ppos) 1935 { 1936 char tmp[PROC_FDINFO_MAX]; 1937 int err = proc_fd_info(file->f_path.dentry->d_inode, NULL, tmp); 1938 if (!err) 1939 err = simple_read_from_buffer(buf, len, ppos, tmp, strlen(tmp)); 1940 return err; 1941 } 1942 1943 static const struct file_operations proc_fdinfo_file_operations = { 1944 .open = nonseekable_open, 1945 .read = proc_fdinfo_read, 1946 }; 1947 1948 static const struct file_operations proc_fd_operations = { 1949 .read = generic_read_dir, 1950 .readdir = proc_readfd, 1951 }; 1952 1953 /* 1954 * /proc/pid/fd needs a special permission handler so that a process can still 1955 * access /proc/self/fd after it has executed a setuid(). 1956 */ 1957 static int proc_fd_permission(struct inode *inode, int mask) 1958 { 1959 int rv; 1960 1961 rv = generic_permission(inode, mask, NULL); 1962 if (rv == 0) 1963 return 0; 1964 if (task_pid(current) == proc_pid(inode)) 1965 rv = 0; 1966 return rv; 1967 } 1968 1969 /* 1970 * proc directories can do almost nothing.. 1971 */ 1972 static const struct inode_operations proc_fd_inode_operations = { 1973 .lookup = proc_lookupfd, 1974 .permission = proc_fd_permission, 1975 .setattr = proc_setattr, 1976 }; 1977 1978 static struct dentry *proc_fdinfo_instantiate(struct inode *dir, 1979 struct dentry *dentry, struct task_struct *task, const void *ptr) 1980 { 1981 unsigned fd = *(unsigned *)ptr; 1982 struct inode *inode; 1983 struct proc_inode *ei; 1984 struct dentry *error = ERR_PTR(-ENOENT); 1985 1986 inode = proc_pid_make_inode(dir->i_sb, task); 1987 if (!inode) 1988 goto out; 1989 ei = PROC_I(inode); 1990 ei->fd = fd; 1991 inode->i_mode = S_IFREG | S_IRUSR; 1992 inode->i_fop = &proc_fdinfo_file_operations; 1993 dentry->d_op = &tid_fd_dentry_operations; 1994 d_add(dentry, inode); 1995 /* Close the race of the process dying before we return the dentry */ 1996 if (tid_fd_revalidate(dentry, NULL)) 1997 error = NULL; 1998 1999 out: 2000 return error; 2001 } 2002 2003 static struct dentry *proc_lookupfdinfo(struct inode *dir, 2004 struct dentry *dentry, 2005 struct nameidata *nd) 2006 { 2007 return proc_lookupfd_common(dir, dentry, proc_fdinfo_instantiate); 2008 } 2009 2010 static int proc_readfdinfo(struct file *filp, void *dirent, filldir_t filldir) 2011 { 2012 return proc_readfd_common(filp, dirent, filldir, 2013 proc_fdinfo_instantiate); 2014 } 2015 2016 static const struct file_operations proc_fdinfo_operations = { 2017 .read = generic_read_dir, 2018 .readdir = proc_readfdinfo, 2019 }; 2020 2021 /* 2022 * proc directories can do almost nothing.. 2023 */ 2024 static const struct inode_operations proc_fdinfo_inode_operations = { 2025 .lookup = proc_lookupfdinfo, 2026 .setattr = proc_setattr, 2027 }; 2028 2029 2030 static struct dentry *proc_pident_instantiate(struct inode *dir, 2031 struct dentry *dentry, struct task_struct *task, const void *ptr) 2032 { 2033 const struct pid_entry *p = ptr; 2034 struct inode *inode; 2035 struct proc_inode *ei; 2036 struct dentry *error = ERR_PTR(-ENOENT); 2037 2038 inode = proc_pid_make_inode(dir->i_sb, task); 2039 if (!inode) 2040 goto out; 2041 2042 ei = PROC_I(inode); 2043 inode->i_mode = p->mode; 2044 if (S_ISDIR(inode->i_mode)) 2045 inode->i_nlink = 2; /* Use getattr to fix if necessary */ 2046 if (p->iop) 2047 inode->i_op = p->iop; 2048 if (p->fop) 2049 inode->i_fop = p->fop; 2050 ei->op = p->op; 2051 dentry->d_op = &pid_dentry_operations; 2052 d_add(dentry, inode); 2053 /* Close the race of the process dying before we return the dentry */ 2054 if (pid_revalidate(dentry, NULL)) 2055 error = NULL; 2056 out: 2057 return error; 2058 } 2059 2060 static struct dentry *proc_pident_lookup(struct inode *dir, 2061 struct dentry *dentry, 2062 const struct pid_entry *ents, 2063 unsigned int nents) 2064 { 2065 struct dentry *error; 2066 struct task_struct *task = get_proc_task(dir); 2067 const struct pid_entry *p, *last; 2068 2069 error = ERR_PTR(-ENOENT); 2070 2071 if (!task) 2072 goto out_no_task; 2073 2074 /* 2075 * Yes, it does not scale. And it should not. Don't add 2076 * new entries into /proc/<tgid>/ without very good reasons. 2077 */ 2078 last = &ents[nents - 1]; 2079 for (p = ents; p <= last; p++) { 2080 if (p->len != dentry->d_name.len) 2081 continue; 2082 if (!memcmp(dentry->d_name.name, p->name, p->len)) 2083 break; 2084 } 2085 if (p > last) 2086 goto out; 2087 2088 error = proc_pident_instantiate(dir, dentry, task, p); 2089 out: 2090 put_task_struct(task); 2091 out_no_task: 2092 return error; 2093 } 2094 2095 static int proc_pident_fill_cache(struct file *filp, void *dirent, 2096 filldir_t filldir, struct task_struct *task, const struct pid_entry *p) 2097 { 2098 return proc_fill_cache(filp, dirent, filldir, p->name, p->len, 2099 proc_pident_instantiate, task, p); 2100 } 2101 2102 static int proc_pident_readdir(struct file *filp, 2103 void *dirent, filldir_t filldir, 2104 const struct pid_entry *ents, unsigned int nents) 2105 { 2106 int i; 2107 struct dentry *dentry = filp->f_path.dentry; 2108 struct inode *inode = dentry->d_inode; 2109 struct task_struct *task = get_proc_task(inode); 2110 const struct pid_entry *p, *last; 2111 ino_t ino; 2112 int ret; 2113 2114 ret = -ENOENT; 2115 if (!task) 2116 goto out_no_task; 2117 2118 ret = 0; 2119 i = filp->f_pos; 2120 switch (i) { 2121 case 0: 2122 ino = inode->i_ino; 2123 if (filldir(dirent, ".", 1, i, ino, DT_DIR) < 0) 2124 goto out; 2125 i++; 2126 filp->f_pos++; 2127 /* fall through */ 2128 case 1: 2129 ino = parent_ino(dentry); 2130 if (filldir(dirent, "..", 2, i, ino, DT_DIR) < 0) 2131 goto out; 2132 i++; 2133 filp->f_pos++; 2134 /* fall through */ 2135 default: 2136 i -= 2; 2137 if (i >= nents) { 2138 ret = 1; 2139 goto out; 2140 } 2141 p = ents + i; 2142 last = &ents[nents - 1]; 2143 while (p <= last) { 2144 if (proc_pident_fill_cache(filp, dirent, filldir, task, p) < 0) 2145 goto out; 2146 filp->f_pos++; 2147 p++; 2148 } 2149 } 2150 2151 ret = 1; 2152 out: 2153 put_task_struct(task); 2154 out_no_task: 2155 return ret; 2156 } 2157 2158 #ifdef CONFIG_SECURITY 2159 static ssize_t proc_pid_attr_read(struct file * file, char __user * buf, 2160 size_t count, loff_t *ppos) 2161 { 2162 struct inode * inode = file->f_path.dentry->d_inode; 2163 char *p = NULL; 2164 ssize_t length; 2165 struct task_struct *task = get_proc_task(inode); 2166 2167 if (!task) 2168 return -ESRCH; 2169 2170 length = security_getprocattr(task, 2171 (char*)file->f_path.dentry->d_name.name, 2172 &p); 2173 put_task_struct(task); 2174 if (length > 0) 2175 length = simple_read_from_buffer(buf, count, ppos, p, length); 2176 kfree(p); 2177 return length; 2178 } 2179 2180 static ssize_t proc_pid_attr_write(struct file * file, const char __user * buf, 2181 size_t count, loff_t *ppos) 2182 { 2183 struct inode * inode = file->f_path.dentry->d_inode; 2184 char *page; 2185 ssize_t length; 2186 struct task_struct *task = get_proc_task(inode); 2187 2188 length = -ESRCH; 2189 if (!task) 2190 goto out_no_task; 2191 if (count > PAGE_SIZE) 2192 count = PAGE_SIZE; 2193 2194 /* No partial writes. */ 2195 length = -EINVAL; 2196 if (*ppos != 0) 2197 goto out; 2198 2199 length = -ENOMEM; 2200 page = (char*)__get_free_page(GFP_TEMPORARY); 2201 if (!page) 2202 goto out; 2203 2204 length = -EFAULT; 2205 if (copy_from_user(page, buf, count)) 2206 goto out_free; 2207 2208 /* Guard against adverse ptrace interaction */ 2209 length = mutex_lock_interruptible(&task->cred_guard_mutex); 2210 if (length < 0) 2211 goto out_free; 2212 2213 length = security_setprocattr(task, 2214 (char*)file->f_path.dentry->d_name.name, 2215 (void*)page, count); 2216 mutex_unlock(&task->cred_guard_mutex); 2217 out_free: 2218 free_page((unsigned long) page); 2219 out: 2220 put_task_struct(task); 2221 out_no_task: 2222 return length; 2223 } 2224 2225 static const struct file_operations proc_pid_attr_operations = { 2226 .read = proc_pid_attr_read, 2227 .write = proc_pid_attr_write, 2228 }; 2229 2230 static const struct pid_entry attr_dir_stuff[] = { 2231 REG("current", S_IRUGO|S_IWUGO, proc_pid_attr_operations), 2232 REG("prev", S_IRUGO, proc_pid_attr_operations), 2233 REG("exec", S_IRUGO|S_IWUGO, proc_pid_attr_operations), 2234 REG("fscreate", S_IRUGO|S_IWUGO, proc_pid_attr_operations), 2235 REG("keycreate", S_IRUGO|S_IWUGO, proc_pid_attr_operations), 2236 REG("sockcreate", S_IRUGO|S_IWUGO, proc_pid_attr_operations), 2237 }; 2238 2239 static int proc_attr_dir_readdir(struct file * filp, 2240 void * dirent, filldir_t filldir) 2241 { 2242 return proc_pident_readdir(filp,dirent,filldir, 2243 attr_dir_stuff,ARRAY_SIZE(attr_dir_stuff)); 2244 } 2245 2246 static const struct file_operations proc_attr_dir_operations = { 2247 .read = generic_read_dir, 2248 .readdir = proc_attr_dir_readdir, 2249 }; 2250 2251 static struct dentry *proc_attr_dir_lookup(struct inode *dir, 2252 struct dentry *dentry, struct nameidata *nd) 2253 { 2254 return proc_pident_lookup(dir, dentry, 2255 attr_dir_stuff, ARRAY_SIZE(attr_dir_stuff)); 2256 } 2257 2258 static const struct inode_operations proc_attr_dir_inode_operations = { 2259 .lookup = proc_attr_dir_lookup, 2260 .getattr = pid_getattr, 2261 .setattr = proc_setattr, 2262 }; 2263 2264 #endif 2265 2266 #ifdef CONFIG_ELF_CORE 2267 static ssize_t proc_coredump_filter_read(struct file *file, char __user *buf, 2268 size_t count, loff_t *ppos) 2269 { 2270 struct task_struct *task = get_proc_task(file->f_dentry->d_inode); 2271 struct mm_struct *mm; 2272 char buffer[PROC_NUMBUF]; 2273 size_t len; 2274 int ret; 2275 2276 if (!task) 2277 return -ESRCH; 2278 2279 ret = 0; 2280 mm = get_task_mm(task); 2281 if (mm) { 2282 len = snprintf(buffer, sizeof(buffer), "%08lx\n", 2283 ((mm->flags & MMF_DUMP_FILTER_MASK) >> 2284 MMF_DUMP_FILTER_SHIFT)); 2285 mmput(mm); 2286 ret = simple_read_from_buffer(buf, count, ppos, buffer, len); 2287 } 2288 2289 put_task_struct(task); 2290 2291 return ret; 2292 } 2293 2294 static ssize_t proc_coredump_filter_write(struct file *file, 2295 const char __user *buf, 2296 size_t count, 2297 loff_t *ppos) 2298 { 2299 struct task_struct *task; 2300 struct mm_struct *mm; 2301 char buffer[PROC_NUMBUF], *end; 2302 unsigned int val; 2303 int ret; 2304 int i; 2305 unsigned long mask; 2306 2307 ret = -EFAULT; 2308 memset(buffer, 0, sizeof(buffer)); 2309 if (count > sizeof(buffer) - 1) 2310 count = sizeof(buffer) - 1; 2311 if (copy_from_user(buffer, buf, count)) 2312 goto out_no_task; 2313 2314 ret = -EINVAL; 2315 val = (unsigned int)simple_strtoul(buffer, &end, 0); 2316 if (*end == '\n') 2317 end++; 2318 if (end - buffer == 0) 2319 goto out_no_task; 2320 2321 ret = -ESRCH; 2322 task = get_proc_task(file->f_dentry->d_inode); 2323 if (!task) 2324 goto out_no_task; 2325 2326 ret = end - buffer; 2327 mm = get_task_mm(task); 2328 if (!mm) 2329 goto out_no_mm; 2330 2331 for (i = 0, mask = 1; i < MMF_DUMP_FILTER_BITS; i++, mask <<= 1) { 2332 if (val & mask) 2333 set_bit(i + MMF_DUMP_FILTER_SHIFT, &mm->flags); 2334 else 2335 clear_bit(i + MMF_DUMP_FILTER_SHIFT, &mm->flags); 2336 } 2337 2338 mmput(mm); 2339 out_no_mm: 2340 put_task_struct(task); 2341 out_no_task: 2342 return ret; 2343 } 2344 2345 static const struct file_operations proc_coredump_filter_operations = { 2346 .read = proc_coredump_filter_read, 2347 .write = proc_coredump_filter_write, 2348 }; 2349 #endif 2350 2351 /* 2352 * /proc/self: 2353 */ 2354 static int proc_self_readlink(struct dentry *dentry, char __user *buffer, 2355 int buflen) 2356 { 2357 struct pid_namespace *ns = dentry->d_sb->s_fs_info; 2358 pid_t tgid = task_tgid_nr_ns(current, ns); 2359 char tmp[PROC_NUMBUF]; 2360 if (!tgid) 2361 return -ENOENT; 2362 sprintf(tmp, "%d", tgid); 2363 return vfs_readlink(dentry,buffer,buflen,tmp); 2364 } 2365 2366 static void *proc_self_follow_link(struct dentry *dentry, struct nameidata *nd) 2367 { 2368 struct pid_namespace *ns = dentry->d_sb->s_fs_info; 2369 pid_t tgid = task_tgid_nr_ns(current, ns); 2370 char *name = ERR_PTR(-ENOENT); 2371 if (tgid) { 2372 name = __getname(); 2373 if (!name) 2374 name = ERR_PTR(-ENOMEM); 2375 else 2376 sprintf(name, "%d", tgid); 2377 } 2378 nd_set_link(nd, name); 2379 return NULL; 2380 } 2381 2382 static void proc_self_put_link(struct dentry *dentry, struct nameidata *nd, 2383 void *cookie) 2384 { 2385 char *s = nd_get_link(nd); 2386 if (!IS_ERR(s)) 2387 __putname(s); 2388 } 2389 2390 static const struct inode_operations proc_self_inode_operations = { 2391 .readlink = proc_self_readlink, 2392 .follow_link = proc_self_follow_link, 2393 .put_link = proc_self_put_link, 2394 }; 2395 2396 /* 2397 * proc base 2398 * 2399 * These are the directory entries in the root directory of /proc 2400 * that properly belong to the /proc filesystem, as they describe 2401 * describe something that is process related. 2402 */ 2403 static const struct pid_entry proc_base_stuff[] = { 2404 NOD("self", S_IFLNK|S_IRWXUGO, 2405 &proc_self_inode_operations, NULL, {}), 2406 }; 2407 2408 /* 2409 * Exceptional case: normally we are not allowed to unhash a busy 2410 * directory. In this case, however, we can do it - no aliasing problems 2411 * due to the way we treat inodes. 2412 */ 2413 static int proc_base_revalidate(struct dentry *dentry, struct nameidata *nd) 2414 { 2415 struct inode *inode = dentry->d_inode; 2416 struct task_struct *task = get_proc_task(inode); 2417 if (task) { 2418 put_task_struct(task); 2419 return 1; 2420 } 2421 d_drop(dentry); 2422 return 0; 2423 } 2424 2425 static const struct dentry_operations proc_base_dentry_operations = 2426 { 2427 .d_revalidate = proc_base_revalidate, 2428 .d_delete = pid_delete_dentry, 2429 }; 2430 2431 static struct dentry *proc_base_instantiate(struct inode *dir, 2432 struct dentry *dentry, struct task_struct *task, const void *ptr) 2433 { 2434 const struct pid_entry *p = ptr; 2435 struct inode *inode; 2436 struct proc_inode *ei; 2437 struct dentry *error = ERR_PTR(-EINVAL); 2438 2439 /* Allocate the inode */ 2440 error = ERR_PTR(-ENOMEM); 2441 inode = new_inode(dir->i_sb); 2442 if (!inode) 2443 goto out; 2444 2445 /* Initialize the inode */ 2446 ei = PROC_I(inode); 2447 inode->i_mtime = inode->i_atime = inode->i_ctime = CURRENT_TIME; 2448 2449 /* 2450 * grab the reference to the task. 2451 */ 2452 ei->pid = get_task_pid(task, PIDTYPE_PID); 2453 if (!ei->pid) 2454 goto out_iput; 2455 2456 inode->i_mode = p->mode; 2457 if (S_ISDIR(inode->i_mode)) 2458 inode->i_nlink = 2; 2459 if (S_ISLNK(inode->i_mode)) 2460 inode->i_size = 64; 2461 if (p->iop) 2462 inode->i_op = p->iop; 2463 if (p->fop) 2464 inode->i_fop = p->fop; 2465 ei->op = p->op; 2466 dentry->d_op = &proc_base_dentry_operations; 2467 d_add(dentry, inode); 2468 error = NULL; 2469 out: 2470 return error; 2471 out_iput: 2472 iput(inode); 2473 goto out; 2474 } 2475 2476 static struct dentry *proc_base_lookup(struct inode *dir, struct dentry *dentry) 2477 { 2478 struct dentry *error; 2479 struct task_struct *task = get_proc_task(dir); 2480 const struct pid_entry *p, *last; 2481 2482 error = ERR_PTR(-ENOENT); 2483 2484 if (!task) 2485 goto out_no_task; 2486 2487 /* Lookup the directory entry */ 2488 last = &proc_base_stuff[ARRAY_SIZE(proc_base_stuff) - 1]; 2489 for (p = proc_base_stuff; p <= last; p++) { 2490 if (p->len != dentry->d_name.len) 2491 continue; 2492 if (!memcmp(dentry->d_name.name, p->name, p->len)) 2493 break; 2494 } 2495 if (p > last) 2496 goto out; 2497 2498 error = proc_base_instantiate(dir, dentry, task, p); 2499 2500 out: 2501 put_task_struct(task); 2502 out_no_task: 2503 return error; 2504 } 2505 2506 static int proc_base_fill_cache(struct file *filp, void *dirent, 2507 filldir_t filldir, struct task_struct *task, const struct pid_entry *p) 2508 { 2509 return proc_fill_cache(filp, dirent, filldir, p->name, p->len, 2510 proc_base_instantiate, task, p); 2511 } 2512 2513 #ifdef CONFIG_TASK_IO_ACCOUNTING 2514 static int do_io_accounting(struct task_struct *task, char *buffer, int whole) 2515 { 2516 struct task_io_accounting acct = task->ioac; 2517 unsigned long flags; 2518 2519 if (whole && lock_task_sighand(task, &flags)) { 2520 struct task_struct *t = task; 2521 2522 task_io_accounting_add(&acct, &task->signal->ioac); 2523 while_each_thread(task, t) 2524 task_io_accounting_add(&acct, &t->ioac); 2525 2526 unlock_task_sighand(task, &flags); 2527 } 2528 return sprintf(buffer, 2529 "rchar: %llu\n" 2530 "wchar: %llu\n" 2531 "syscr: %llu\n" 2532 "syscw: %llu\n" 2533 "read_bytes: %llu\n" 2534 "write_bytes: %llu\n" 2535 "cancelled_write_bytes: %llu\n", 2536 (unsigned long long)acct.rchar, 2537 (unsigned long long)acct.wchar, 2538 (unsigned long long)acct.syscr, 2539 (unsigned long long)acct.syscw, 2540 (unsigned long long)acct.read_bytes, 2541 (unsigned long long)acct.write_bytes, 2542 (unsigned long long)acct.cancelled_write_bytes); 2543 } 2544 2545 static int proc_tid_io_accounting(struct task_struct *task, char *buffer) 2546 { 2547 return do_io_accounting(task, buffer, 0); 2548 } 2549 2550 static int proc_tgid_io_accounting(struct task_struct *task, char *buffer) 2551 { 2552 return do_io_accounting(task, buffer, 1); 2553 } 2554 #endif /* CONFIG_TASK_IO_ACCOUNTING */ 2555 2556 static int proc_pid_personality(struct seq_file *m, struct pid_namespace *ns, 2557 struct pid *pid, struct task_struct *task) 2558 { 2559 seq_printf(m, "%08x\n", task->personality); 2560 return 0; 2561 } 2562 2563 /* 2564 * Thread groups 2565 */ 2566 static const struct file_operations proc_task_operations; 2567 static const struct inode_operations proc_task_inode_operations; 2568 2569 static const struct pid_entry tgid_base_stuff[] = { 2570 DIR("task", S_IRUGO|S_IXUGO, proc_task_inode_operations, proc_task_operations), 2571 DIR("fd", S_IRUSR|S_IXUSR, proc_fd_inode_operations, proc_fd_operations), 2572 DIR("fdinfo", S_IRUSR|S_IXUSR, proc_fdinfo_inode_operations, proc_fdinfo_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_IRUSR, proc_pid_personality), 2580 INF("limits", S_IRUSR, proc_pid_limits), 2581 #ifdef CONFIG_SCHED_DEBUG 2582 REG("sched", S_IRUGO|S_IWUSR, proc_pid_sched_operations), 2583 #endif 2584 REG("comm", S_IRUGO|S_IWUSR, proc_pid_set_comm_operations), 2585 #ifdef CONFIG_HAVE_ARCH_TRACEHOOK 2586 INF("syscall", S_IRUSR, proc_pid_syscall), 2587 #endif 2588 INF("cmdline", S_IRUGO, proc_pid_cmdline), 2589 ONE("stat", S_IRUGO, proc_tgid_stat), 2590 ONE("statm", S_IRUGO, proc_pid_statm), 2591 REG("maps", S_IRUGO, proc_maps_operations), 2592 #ifdef CONFIG_NUMA 2593 REG("numa_maps", S_IRUGO, proc_numa_maps_operations), 2594 #endif 2595 REG("mem", S_IRUSR|S_IWUSR, proc_mem_operations), 2596 LNK("cwd", proc_cwd_link), 2597 LNK("root", proc_root_link), 2598 LNK("exe", proc_exe_link), 2599 REG("mounts", S_IRUGO, proc_mounts_operations), 2600 REG("mountinfo", S_IRUGO, proc_mountinfo_operations), 2601 REG("mountstats", S_IRUSR, proc_mountstats_operations), 2602 #ifdef CONFIG_PROC_PAGE_MONITOR 2603 REG("clear_refs", S_IWUSR, proc_clear_refs_operations), 2604 REG("smaps", S_IRUGO, proc_smaps_operations), 2605 REG("pagemap", S_IRUSR, proc_pagemap_operations), 2606 #endif 2607 #ifdef CONFIG_SECURITY 2608 DIR("attr", S_IRUGO|S_IXUGO, proc_attr_dir_inode_operations, proc_attr_dir_operations), 2609 #endif 2610 #ifdef CONFIG_KALLSYMS 2611 INF("wchan", S_IRUGO, proc_pid_wchan), 2612 #endif 2613 #ifdef CONFIG_STACKTRACE 2614 ONE("stack", S_IRUSR, proc_pid_stack), 2615 #endif 2616 #ifdef CONFIG_SCHEDSTATS 2617 INF("schedstat", S_IRUGO, proc_pid_schedstat), 2618 #endif 2619 #ifdef CONFIG_LATENCYTOP 2620 REG("latency", S_IRUGO, proc_lstats_operations), 2621 #endif 2622 #ifdef CONFIG_PROC_PID_CPUSET 2623 REG("cpuset", S_IRUGO, proc_cpuset_operations), 2624 #endif 2625 #ifdef CONFIG_CGROUPS 2626 REG("cgroup", S_IRUGO, proc_cgroup_operations), 2627 #endif 2628 INF("oom_score", S_IRUGO, proc_oom_score), 2629 REG("oom_adj", S_IRUGO|S_IWUSR, proc_oom_adjust_operations), 2630 #ifdef CONFIG_AUDITSYSCALL 2631 REG("loginuid", S_IWUSR|S_IRUGO, proc_loginuid_operations), 2632 REG("sessionid", S_IRUGO, proc_sessionid_operations), 2633 #endif 2634 #ifdef CONFIG_FAULT_INJECTION 2635 REG("make-it-fail", S_IRUGO|S_IWUSR, proc_fault_inject_operations), 2636 #endif 2637 #ifdef CONFIG_ELF_CORE 2638 REG("coredump_filter", S_IRUGO|S_IWUSR, proc_coredump_filter_operations), 2639 #endif 2640 #ifdef CONFIG_TASK_IO_ACCOUNTING 2641 INF("io", S_IRUGO, proc_tgid_io_accounting), 2642 #endif 2643 }; 2644 2645 static int proc_tgid_base_readdir(struct file * filp, 2646 void * dirent, filldir_t filldir) 2647 { 2648 return proc_pident_readdir(filp,dirent,filldir, 2649 tgid_base_stuff,ARRAY_SIZE(tgid_base_stuff)); 2650 } 2651 2652 static const struct file_operations proc_tgid_base_operations = { 2653 .read = generic_read_dir, 2654 .readdir = proc_tgid_base_readdir, 2655 }; 2656 2657 static struct dentry *proc_tgid_base_lookup(struct inode *dir, struct dentry *dentry, struct nameidata *nd){ 2658 return proc_pident_lookup(dir, dentry, 2659 tgid_base_stuff, ARRAY_SIZE(tgid_base_stuff)); 2660 } 2661 2662 static const struct inode_operations proc_tgid_base_inode_operations = { 2663 .lookup = proc_tgid_base_lookup, 2664 .getattr = pid_getattr, 2665 .setattr = proc_setattr, 2666 }; 2667 2668 static void proc_flush_task_mnt(struct vfsmount *mnt, pid_t pid, pid_t tgid) 2669 { 2670 struct dentry *dentry, *leader, *dir; 2671 char buf[PROC_NUMBUF]; 2672 struct qstr name; 2673 2674 name.name = buf; 2675 name.len = snprintf(buf, sizeof(buf), "%d", pid); 2676 dentry = d_hash_and_lookup(mnt->mnt_root, &name); 2677 if (dentry) { 2678 shrink_dcache_parent(dentry); 2679 d_drop(dentry); 2680 dput(dentry); 2681 } 2682 2683 name.name = buf; 2684 name.len = snprintf(buf, sizeof(buf), "%d", tgid); 2685 leader = d_hash_and_lookup(mnt->mnt_root, &name); 2686 if (!leader) 2687 goto out; 2688 2689 name.name = "task"; 2690 name.len = strlen(name.name); 2691 dir = d_hash_and_lookup(leader, &name); 2692 if (!dir) 2693 goto out_put_leader; 2694 2695 name.name = buf; 2696 name.len = snprintf(buf, sizeof(buf), "%d", pid); 2697 dentry = d_hash_and_lookup(dir, &name); 2698 if (dentry) { 2699 shrink_dcache_parent(dentry); 2700 d_drop(dentry); 2701 dput(dentry); 2702 } 2703 2704 dput(dir); 2705 out_put_leader: 2706 dput(leader); 2707 out: 2708 return; 2709 } 2710 2711 /** 2712 * proc_flush_task - Remove dcache entries for @task from the /proc dcache. 2713 * @task: task that should be flushed. 2714 * 2715 * When flushing dentries from proc, one needs to flush them from global 2716 * proc (proc_mnt) and from all the namespaces' procs this task was seen 2717 * in. This call is supposed to do all of this job. 2718 * 2719 * Looks in the dcache for 2720 * /proc/@pid 2721 * /proc/@tgid/task/@pid 2722 * if either directory is present flushes it and all of it'ts children 2723 * from the dcache. 2724 * 2725 * It is safe and reasonable to cache /proc entries for a task until 2726 * that task exits. After that they just clog up the dcache with 2727 * useless entries, possibly causing useful dcache entries to be 2728 * flushed instead. This routine is proved to flush those useless 2729 * dcache entries at process exit time. 2730 * 2731 * NOTE: This routine is just an optimization so it does not guarantee 2732 * that no dcache entries will exist at process exit time it 2733 * just makes it very unlikely that any will persist. 2734 */ 2735 2736 void proc_flush_task(struct task_struct *task) 2737 { 2738 int i; 2739 struct pid *pid, *tgid; 2740 struct upid *upid; 2741 2742 pid = task_pid(task); 2743 tgid = task_tgid(task); 2744 2745 for (i = 0; i <= pid->level; i++) { 2746 upid = &pid->numbers[i]; 2747 proc_flush_task_mnt(upid->ns->proc_mnt, upid->nr, 2748 tgid->numbers[i].nr); 2749 } 2750 2751 upid = &pid->numbers[pid->level]; 2752 if (upid->nr == 1) 2753 pid_ns_release_proc(upid->ns); 2754 } 2755 2756 static struct dentry *proc_pid_instantiate(struct inode *dir, 2757 struct dentry * dentry, 2758 struct task_struct *task, const void *ptr) 2759 { 2760 struct dentry *error = ERR_PTR(-ENOENT); 2761 struct inode *inode; 2762 2763 inode = proc_pid_make_inode(dir->i_sb, task); 2764 if (!inode) 2765 goto out; 2766 2767 inode->i_mode = S_IFDIR|S_IRUGO|S_IXUGO; 2768 inode->i_op = &proc_tgid_base_inode_operations; 2769 inode->i_fop = &proc_tgid_base_operations; 2770 inode->i_flags|=S_IMMUTABLE; 2771 2772 inode->i_nlink = 2 + pid_entry_count_dirs(tgid_base_stuff, 2773 ARRAY_SIZE(tgid_base_stuff)); 2774 2775 dentry->d_op = &pid_dentry_operations; 2776 2777 d_add(dentry, inode); 2778 /* Close the race of the process dying before we return the dentry */ 2779 if (pid_revalidate(dentry, NULL)) 2780 error = NULL; 2781 out: 2782 return error; 2783 } 2784 2785 struct dentry *proc_pid_lookup(struct inode *dir, struct dentry * dentry, struct nameidata *nd) 2786 { 2787 struct dentry *result = ERR_PTR(-ENOENT); 2788 struct task_struct *task; 2789 unsigned tgid; 2790 struct pid_namespace *ns; 2791 2792 result = proc_base_lookup(dir, dentry); 2793 if (!IS_ERR(result) || PTR_ERR(result) != -ENOENT) 2794 goto out; 2795 2796 tgid = name_to_int(dentry); 2797 if (tgid == ~0U) 2798 goto out; 2799 2800 ns = dentry->d_sb->s_fs_info; 2801 rcu_read_lock(); 2802 task = find_task_by_pid_ns(tgid, ns); 2803 if (task) 2804 get_task_struct(task); 2805 rcu_read_unlock(); 2806 if (!task) 2807 goto out; 2808 2809 result = proc_pid_instantiate(dir, dentry, task, NULL); 2810 put_task_struct(task); 2811 out: 2812 return result; 2813 } 2814 2815 /* 2816 * Find the first task with tgid >= tgid 2817 * 2818 */ 2819 struct tgid_iter { 2820 unsigned int tgid; 2821 struct task_struct *task; 2822 }; 2823 static struct tgid_iter next_tgid(struct pid_namespace *ns, struct tgid_iter iter) 2824 { 2825 struct pid *pid; 2826 2827 if (iter.task) 2828 put_task_struct(iter.task); 2829 rcu_read_lock(); 2830 retry: 2831 iter.task = NULL; 2832 pid = find_ge_pid(iter.tgid, ns); 2833 if (pid) { 2834 iter.tgid = pid_nr_ns(pid, ns); 2835 iter.task = pid_task(pid, PIDTYPE_PID); 2836 /* What we to know is if the pid we have find is the 2837 * pid of a thread_group_leader. Testing for task 2838 * being a thread_group_leader is the obvious thing 2839 * todo but there is a window when it fails, due to 2840 * the pid transfer logic in de_thread. 2841 * 2842 * So we perform the straight forward test of seeing 2843 * if the pid we have found is the pid of a thread 2844 * group leader, and don't worry if the task we have 2845 * found doesn't happen to be a thread group leader. 2846 * As we don't care in the case of readdir. 2847 */ 2848 if (!iter.task || !has_group_leader_pid(iter.task)) { 2849 iter.tgid += 1; 2850 goto retry; 2851 } 2852 get_task_struct(iter.task); 2853 } 2854 rcu_read_unlock(); 2855 return iter; 2856 } 2857 2858 #define TGID_OFFSET (FIRST_PROCESS_ENTRY + ARRAY_SIZE(proc_base_stuff)) 2859 2860 static int proc_pid_fill_cache(struct file *filp, void *dirent, filldir_t filldir, 2861 struct tgid_iter iter) 2862 { 2863 char name[PROC_NUMBUF]; 2864 int len = snprintf(name, sizeof(name), "%d", iter.tgid); 2865 return proc_fill_cache(filp, dirent, filldir, name, len, 2866 proc_pid_instantiate, iter.task, NULL); 2867 } 2868 2869 /* for the /proc/ directory itself, after non-process stuff has been done */ 2870 int proc_pid_readdir(struct file * filp, void * dirent, filldir_t filldir) 2871 { 2872 unsigned int nr = filp->f_pos - FIRST_PROCESS_ENTRY; 2873 struct task_struct *reaper = get_proc_task(filp->f_path.dentry->d_inode); 2874 struct tgid_iter iter; 2875 struct pid_namespace *ns; 2876 2877 if (!reaper) 2878 goto out_no_task; 2879 2880 for (; nr < ARRAY_SIZE(proc_base_stuff); filp->f_pos++, nr++) { 2881 const struct pid_entry *p = &proc_base_stuff[nr]; 2882 if (proc_base_fill_cache(filp, dirent, filldir, reaper, p) < 0) 2883 goto out; 2884 } 2885 2886 ns = filp->f_dentry->d_sb->s_fs_info; 2887 iter.task = NULL; 2888 iter.tgid = filp->f_pos - TGID_OFFSET; 2889 for (iter = next_tgid(ns, iter); 2890 iter.task; 2891 iter.tgid += 1, iter = next_tgid(ns, iter)) { 2892 filp->f_pos = iter.tgid + TGID_OFFSET; 2893 if (proc_pid_fill_cache(filp, dirent, filldir, iter) < 0) { 2894 put_task_struct(iter.task); 2895 goto out; 2896 } 2897 } 2898 filp->f_pos = PID_MAX_LIMIT + TGID_OFFSET; 2899 out: 2900 put_task_struct(reaper); 2901 out_no_task: 2902 return 0; 2903 } 2904 2905 /* 2906 * Tasks 2907 */ 2908 static const struct pid_entry tid_base_stuff[] = { 2909 DIR("fd", S_IRUSR|S_IXUSR, proc_fd_inode_operations, proc_fd_operations), 2910 DIR("fdinfo", S_IRUSR|S_IXUSR, proc_fdinfo_inode_operations, proc_fd_operations), 2911 REG("environ", S_IRUSR, proc_environ_operations), 2912 INF("auxv", S_IRUSR, proc_pid_auxv), 2913 ONE("status", S_IRUGO, proc_pid_status), 2914 ONE("personality", S_IRUSR, proc_pid_personality), 2915 INF("limits", S_IRUSR, proc_pid_limits), 2916 #ifdef CONFIG_SCHED_DEBUG 2917 REG("sched", S_IRUGO|S_IWUSR, proc_pid_sched_operations), 2918 #endif 2919 REG("comm", S_IRUGO|S_IWUSR, proc_pid_set_comm_operations), 2920 #ifdef CONFIG_HAVE_ARCH_TRACEHOOK 2921 INF("syscall", S_IRUSR, proc_pid_syscall), 2922 #endif 2923 INF("cmdline", S_IRUGO, proc_pid_cmdline), 2924 ONE("stat", S_IRUGO, proc_tid_stat), 2925 ONE("statm", S_IRUGO, proc_pid_statm), 2926 REG("maps", S_IRUGO, proc_maps_operations), 2927 #ifdef CONFIG_NUMA 2928 REG("numa_maps", S_IRUGO, proc_numa_maps_operations), 2929 #endif 2930 REG("mem", S_IRUSR|S_IWUSR, proc_mem_operations), 2931 LNK("cwd", proc_cwd_link), 2932 LNK("root", proc_root_link), 2933 LNK("exe", proc_exe_link), 2934 REG("mounts", S_IRUGO, proc_mounts_operations), 2935 REG("mountinfo", S_IRUGO, proc_mountinfo_operations), 2936 #ifdef CONFIG_PROC_PAGE_MONITOR 2937 REG("clear_refs", S_IWUSR, proc_clear_refs_operations), 2938 REG("smaps", S_IRUGO, proc_smaps_operations), 2939 REG("pagemap", S_IRUSR, proc_pagemap_operations), 2940 #endif 2941 #ifdef CONFIG_SECURITY 2942 DIR("attr", S_IRUGO|S_IXUGO, proc_attr_dir_inode_operations, proc_attr_dir_operations), 2943 #endif 2944 #ifdef CONFIG_KALLSYMS 2945 INF("wchan", S_IRUGO, proc_pid_wchan), 2946 #endif 2947 #ifdef CONFIG_STACKTRACE 2948 ONE("stack", S_IRUSR, proc_pid_stack), 2949 #endif 2950 #ifdef CONFIG_SCHEDSTATS 2951 INF("schedstat", S_IRUGO, proc_pid_schedstat), 2952 #endif 2953 #ifdef CONFIG_LATENCYTOP 2954 REG("latency", S_IRUGO, proc_lstats_operations), 2955 #endif 2956 #ifdef CONFIG_PROC_PID_CPUSET 2957 REG("cpuset", S_IRUGO, proc_cpuset_operations), 2958 #endif 2959 #ifdef CONFIG_CGROUPS 2960 REG("cgroup", S_IRUGO, proc_cgroup_operations), 2961 #endif 2962 INF("oom_score", S_IRUGO, proc_oom_score), 2963 REG("oom_adj", S_IRUGO|S_IWUSR, proc_oom_adjust_operations), 2964 #ifdef CONFIG_AUDITSYSCALL 2965 REG("loginuid", S_IWUSR|S_IRUGO, proc_loginuid_operations), 2966 REG("sessionid", S_IRUSR, proc_sessionid_operations), 2967 #endif 2968 #ifdef CONFIG_FAULT_INJECTION 2969 REG("make-it-fail", S_IRUGO|S_IWUSR, proc_fault_inject_operations), 2970 #endif 2971 #ifdef CONFIG_TASK_IO_ACCOUNTING 2972 INF("io", S_IRUGO, proc_tid_io_accounting), 2973 #endif 2974 }; 2975 2976 static int proc_tid_base_readdir(struct file * filp, 2977 void * dirent, filldir_t filldir) 2978 { 2979 return proc_pident_readdir(filp,dirent,filldir, 2980 tid_base_stuff,ARRAY_SIZE(tid_base_stuff)); 2981 } 2982 2983 static struct dentry *proc_tid_base_lookup(struct inode *dir, struct dentry *dentry, struct nameidata *nd){ 2984 return proc_pident_lookup(dir, dentry, 2985 tid_base_stuff, ARRAY_SIZE(tid_base_stuff)); 2986 } 2987 2988 static const struct file_operations proc_tid_base_operations = { 2989 .read = generic_read_dir, 2990 .readdir = proc_tid_base_readdir, 2991 }; 2992 2993 static const struct inode_operations proc_tid_base_inode_operations = { 2994 .lookup = proc_tid_base_lookup, 2995 .getattr = pid_getattr, 2996 .setattr = proc_setattr, 2997 }; 2998 2999 static struct dentry *proc_task_instantiate(struct inode *dir, 3000 struct dentry *dentry, struct task_struct *task, const void *ptr) 3001 { 3002 struct dentry *error = ERR_PTR(-ENOENT); 3003 struct inode *inode; 3004 inode = proc_pid_make_inode(dir->i_sb, task); 3005 3006 if (!inode) 3007 goto out; 3008 inode->i_mode = S_IFDIR|S_IRUGO|S_IXUGO; 3009 inode->i_op = &proc_tid_base_inode_operations; 3010 inode->i_fop = &proc_tid_base_operations; 3011 inode->i_flags|=S_IMMUTABLE; 3012 3013 inode->i_nlink = 2 + pid_entry_count_dirs(tid_base_stuff, 3014 ARRAY_SIZE(tid_base_stuff)); 3015 3016 dentry->d_op = &pid_dentry_operations; 3017 3018 d_add(dentry, inode); 3019 /* Close the race of the process dying before we return the dentry */ 3020 if (pid_revalidate(dentry, NULL)) 3021 error = NULL; 3022 out: 3023 return error; 3024 } 3025 3026 static struct dentry *proc_task_lookup(struct inode *dir, struct dentry * dentry, struct nameidata *nd) 3027 { 3028 struct dentry *result = ERR_PTR(-ENOENT); 3029 struct task_struct *task; 3030 struct task_struct *leader = get_proc_task(dir); 3031 unsigned tid; 3032 struct pid_namespace *ns; 3033 3034 if (!leader) 3035 goto out_no_task; 3036 3037 tid = name_to_int(dentry); 3038 if (tid == ~0U) 3039 goto out; 3040 3041 ns = dentry->d_sb->s_fs_info; 3042 rcu_read_lock(); 3043 task = find_task_by_pid_ns(tid, ns); 3044 if (task) 3045 get_task_struct(task); 3046 rcu_read_unlock(); 3047 if (!task) 3048 goto out; 3049 if (!same_thread_group(leader, task)) 3050 goto out_drop_task; 3051 3052 result = proc_task_instantiate(dir, dentry, task, NULL); 3053 out_drop_task: 3054 put_task_struct(task); 3055 out: 3056 put_task_struct(leader); 3057 out_no_task: 3058 return result; 3059 } 3060 3061 /* 3062 * Find the first tid of a thread group to return to user space. 3063 * 3064 * Usually this is just the thread group leader, but if the users 3065 * buffer was too small or there was a seek into the middle of the 3066 * directory we have more work todo. 3067 * 3068 * In the case of a short read we start with find_task_by_pid. 3069 * 3070 * In the case of a seek we start with the leader and walk nr 3071 * threads past it. 3072 */ 3073 static struct task_struct *first_tid(struct task_struct *leader, 3074 int tid, int nr, struct pid_namespace *ns) 3075 { 3076 struct task_struct *pos; 3077 3078 rcu_read_lock(); 3079 /* Attempt to start with the pid of a thread */ 3080 if (tid && (nr > 0)) { 3081 pos = find_task_by_pid_ns(tid, ns); 3082 if (pos && (pos->group_leader == leader)) 3083 goto found; 3084 } 3085 3086 /* If nr exceeds the number of threads there is nothing todo */ 3087 pos = NULL; 3088 if (nr && nr >= get_nr_threads(leader)) 3089 goto out; 3090 3091 /* If we haven't found our starting place yet start 3092 * with the leader and walk nr threads forward. 3093 */ 3094 for (pos = leader; nr > 0; --nr) { 3095 pos = next_thread(pos); 3096 if (pos == leader) { 3097 pos = NULL; 3098 goto out; 3099 } 3100 } 3101 found: 3102 get_task_struct(pos); 3103 out: 3104 rcu_read_unlock(); 3105 return pos; 3106 } 3107 3108 /* 3109 * Find the next thread in the thread list. 3110 * Return NULL if there is an error or no next thread. 3111 * 3112 * The reference to the input task_struct is released. 3113 */ 3114 static struct task_struct *next_tid(struct task_struct *start) 3115 { 3116 struct task_struct *pos = NULL; 3117 rcu_read_lock(); 3118 if (pid_alive(start)) { 3119 pos = next_thread(start); 3120 if (thread_group_leader(pos)) 3121 pos = NULL; 3122 else 3123 get_task_struct(pos); 3124 } 3125 rcu_read_unlock(); 3126 put_task_struct(start); 3127 return pos; 3128 } 3129 3130 static int proc_task_fill_cache(struct file *filp, void *dirent, filldir_t filldir, 3131 struct task_struct *task, int tid) 3132 { 3133 char name[PROC_NUMBUF]; 3134 int len = snprintf(name, sizeof(name), "%d", tid); 3135 return proc_fill_cache(filp, dirent, filldir, name, len, 3136 proc_task_instantiate, task, NULL); 3137 } 3138 3139 /* for the /proc/TGID/task/ directories */ 3140 static int proc_task_readdir(struct file * filp, void * dirent, filldir_t filldir) 3141 { 3142 struct dentry *dentry = filp->f_path.dentry; 3143 struct inode *inode = dentry->d_inode; 3144 struct task_struct *leader = NULL; 3145 struct task_struct *task; 3146 int retval = -ENOENT; 3147 ino_t ino; 3148 int tid; 3149 struct pid_namespace *ns; 3150 3151 task = get_proc_task(inode); 3152 if (!task) 3153 goto out_no_task; 3154 rcu_read_lock(); 3155 if (pid_alive(task)) { 3156 leader = task->group_leader; 3157 get_task_struct(leader); 3158 } 3159 rcu_read_unlock(); 3160 put_task_struct(task); 3161 if (!leader) 3162 goto out_no_task; 3163 retval = 0; 3164 3165 switch ((unsigned long)filp->f_pos) { 3166 case 0: 3167 ino = inode->i_ino; 3168 if (filldir(dirent, ".", 1, filp->f_pos, ino, DT_DIR) < 0) 3169 goto out; 3170 filp->f_pos++; 3171 /* fall through */ 3172 case 1: 3173 ino = parent_ino(dentry); 3174 if (filldir(dirent, "..", 2, filp->f_pos, ino, DT_DIR) < 0) 3175 goto out; 3176 filp->f_pos++; 3177 /* fall through */ 3178 } 3179 3180 /* f_version caches the tgid value that the last readdir call couldn't 3181 * return. lseek aka telldir automagically resets f_version to 0. 3182 */ 3183 ns = filp->f_dentry->d_sb->s_fs_info; 3184 tid = (int)filp->f_version; 3185 filp->f_version = 0; 3186 for (task = first_tid(leader, tid, filp->f_pos - 2, ns); 3187 task; 3188 task = next_tid(task), filp->f_pos++) { 3189 tid = task_pid_nr_ns(task, ns); 3190 if (proc_task_fill_cache(filp, dirent, filldir, task, tid) < 0) { 3191 /* returning this tgid failed, save it as the first 3192 * pid for the next readir call */ 3193 filp->f_version = (u64)tid; 3194 put_task_struct(task); 3195 break; 3196 } 3197 } 3198 out: 3199 put_task_struct(leader); 3200 out_no_task: 3201 return retval; 3202 } 3203 3204 static int proc_task_getattr(struct vfsmount *mnt, struct dentry *dentry, struct kstat *stat) 3205 { 3206 struct inode *inode = dentry->d_inode; 3207 struct task_struct *p = get_proc_task(inode); 3208 generic_fillattr(inode, stat); 3209 3210 if (p) { 3211 stat->nlink += get_nr_threads(p); 3212 put_task_struct(p); 3213 } 3214 3215 return 0; 3216 } 3217 3218 static const struct inode_operations proc_task_inode_operations = { 3219 .lookup = proc_task_lookup, 3220 .getattr = proc_task_getattr, 3221 .setattr = proc_setattr, 3222 }; 3223 3224 static const struct file_operations proc_task_operations = { 3225 .read = generic_read_dir, 3226 .readdir = proc_task_readdir, 3227 }; 3228