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 struct mnt_namespace *ns = p->ns; 651 unsigned res = POLLIN | POLLRDNORM; 652 653 poll_wait(file, &ns->poll, wait); 654 655 spin_lock(&vfsmount_lock); 656 if (p->event != ns->event) { 657 p->event = ns->event; 658 res |= POLLERR | POLLPRI; 659 } 660 spin_unlock(&vfsmount_lock); 661 662 return res; 663 } 664 665 static int mounts_open(struct inode *inode, struct file *file) 666 { 667 return mounts_open_common(inode, file, &mounts_op); 668 } 669 670 static const struct file_operations proc_mounts_operations = { 671 .open = mounts_open, 672 .read = seq_read, 673 .llseek = seq_lseek, 674 .release = mounts_release, 675 .poll = mounts_poll, 676 }; 677 678 static int mountinfo_open(struct inode *inode, struct file *file) 679 { 680 return mounts_open_common(inode, file, &mountinfo_op); 681 } 682 683 static const struct file_operations proc_mountinfo_operations = { 684 .open = mountinfo_open, 685 .read = seq_read, 686 .llseek = seq_lseek, 687 .release = mounts_release, 688 .poll = mounts_poll, 689 }; 690 691 static int mountstats_open(struct inode *inode, struct file *file) 692 { 693 return mounts_open_common(inode, file, &mountstats_op); 694 } 695 696 static const struct file_operations proc_mountstats_operations = { 697 .open = mountstats_open, 698 .read = seq_read, 699 .llseek = seq_lseek, 700 .release = mounts_release, 701 }; 702 703 #define PROC_BLOCK_SIZE (3*1024) /* 4K page size but our output routines use some slack for overruns */ 704 705 static ssize_t proc_info_read(struct file * file, char __user * buf, 706 size_t count, loff_t *ppos) 707 { 708 struct inode * inode = file->f_path.dentry->d_inode; 709 unsigned long page; 710 ssize_t length; 711 struct task_struct *task = get_proc_task(inode); 712 713 length = -ESRCH; 714 if (!task) 715 goto out_no_task; 716 717 if (count > PROC_BLOCK_SIZE) 718 count = PROC_BLOCK_SIZE; 719 720 length = -ENOMEM; 721 if (!(page = __get_free_page(GFP_TEMPORARY))) 722 goto out; 723 724 length = PROC_I(inode)->op.proc_read(task, (char*)page); 725 726 if (length >= 0) 727 length = simple_read_from_buffer(buf, count, ppos, (char *)page, length); 728 free_page(page); 729 out: 730 put_task_struct(task); 731 out_no_task: 732 return length; 733 } 734 735 static const struct file_operations proc_info_file_operations = { 736 .read = proc_info_read, 737 }; 738 739 static int proc_single_show(struct seq_file *m, void *v) 740 { 741 struct inode *inode = m->private; 742 struct pid_namespace *ns; 743 struct pid *pid; 744 struct task_struct *task; 745 int ret; 746 747 ns = inode->i_sb->s_fs_info; 748 pid = proc_pid(inode); 749 task = get_pid_task(pid, PIDTYPE_PID); 750 if (!task) 751 return -ESRCH; 752 753 ret = PROC_I(inode)->op.proc_show(m, ns, pid, task); 754 755 put_task_struct(task); 756 return ret; 757 } 758 759 static int proc_single_open(struct inode *inode, struct file *filp) 760 { 761 int ret; 762 ret = single_open(filp, proc_single_show, NULL); 763 if (!ret) { 764 struct seq_file *m = filp->private_data; 765 766 m->private = inode; 767 } 768 return ret; 769 } 770 771 static const struct file_operations proc_single_file_operations = { 772 .open = proc_single_open, 773 .read = seq_read, 774 .llseek = seq_lseek, 775 .release = single_release, 776 }; 777 778 static int mem_open(struct inode* inode, struct file* file) 779 { 780 file->private_data = (void*)((long)current->self_exec_id); 781 return 0; 782 } 783 784 static ssize_t mem_read(struct file * file, char __user * buf, 785 size_t count, loff_t *ppos) 786 { 787 struct task_struct *task = get_proc_task(file->f_path.dentry->d_inode); 788 char *page; 789 unsigned long src = *ppos; 790 int ret = -ESRCH; 791 struct mm_struct *mm; 792 793 if (!task) 794 goto out_no_task; 795 796 if (check_mem_permission(task)) 797 goto out; 798 799 ret = -ENOMEM; 800 page = (char *)__get_free_page(GFP_TEMPORARY); 801 if (!page) 802 goto out; 803 804 ret = 0; 805 806 mm = get_task_mm(task); 807 if (!mm) 808 goto out_free; 809 810 ret = -EIO; 811 812 if (file->private_data != (void*)((long)current->self_exec_id)) 813 goto out_put; 814 815 ret = 0; 816 817 while (count > 0) { 818 int this_len, retval; 819 820 this_len = (count > PAGE_SIZE) ? PAGE_SIZE : count; 821 retval = access_process_vm(task, src, page, this_len, 0); 822 if (!retval || check_mem_permission(task)) { 823 if (!ret) 824 ret = -EIO; 825 break; 826 } 827 828 if (copy_to_user(buf, page, retval)) { 829 ret = -EFAULT; 830 break; 831 } 832 833 ret += retval; 834 src += retval; 835 buf += retval; 836 count -= retval; 837 } 838 *ppos = src; 839 840 out_put: 841 mmput(mm); 842 out_free: 843 free_page((unsigned long) page); 844 out: 845 put_task_struct(task); 846 out_no_task: 847 return ret; 848 } 849 850 #define mem_write NULL 851 852 #ifndef mem_write 853 /* This is a security hazard */ 854 static ssize_t mem_write(struct file * file, const char __user *buf, 855 size_t count, loff_t *ppos) 856 { 857 int copied; 858 char *page; 859 struct task_struct *task = get_proc_task(file->f_path.dentry->d_inode); 860 unsigned long dst = *ppos; 861 862 copied = -ESRCH; 863 if (!task) 864 goto out_no_task; 865 866 if (check_mem_permission(task)) 867 goto out; 868 869 copied = -ENOMEM; 870 page = (char *)__get_free_page(GFP_TEMPORARY); 871 if (!page) 872 goto out; 873 874 copied = 0; 875 while (count > 0) { 876 int this_len, retval; 877 878 this_len = (count > PAGE_SIZE) ? PAGE_SIZE : count; 879 if (copy_from_user(page, buf, this_len)) { 880 copied = -EFAULT; 881 break; 882 } 883 retval = access_process_vm(task, dst, page, this_len, 1); 884 if (!retval) { 885 if (!copied) 886 copied = -EIO; 887 break; 888 } 889 copied += retval; 890 buf += retval; 891 dst += retval; 892 count -= retval; 893 } 894 *ppos = dst; 895 free_page((unsigned long) page); 896 out: 897 put_task_struct(task); 898 out_no_task: 899 return copied; 900 } 901 #endif 902 903 loff_t mem_lseek(struct file *file, loff_t offset, int orig) 904 { 905 switch (orig) { 906 case 0: 907 file->f_pos = offset; 908 break; 909 case 1: 910 file->f_pos += offset; 911 break; 912 default: 913 return -EINVAL; 914 } 915 force_successful_syscall_return(); 916 return file->f_pos; 917 } 918 919 static const struct file_operations proc_mem_operations = { 920 .llseek = mem_lseek, 921 .read = mem_read, 922 .write = mem_write, 923 .open = mem_open, 924 }; 925 926 static ssize_t environ_read(struct file *file, char __user *buf, 927 size_t count, loff_t *ppos) 928 { 929 struct task_struct *task = get_proc_task(file->f_dentry->d_inode); 930 char *page; 931 unsigned long src = *ppos; 932 int ret = -ESRCH; 933 struct mm_struct *mm; 934 935 if (!task) 936 goto out_no_task; 937 938 if (!ptrace_may_access(task, PTRACE_MODE_READ)) 939 goto out; 940 941 ret = -ENOMEM; 942 page = (char *)__get_free_page(GFP_TEMPORARY); 943 if (!page) 944 goto out; 945 946 ret = 0; 947 948 mm = get_task_mm(task); 949 if (!mm) 950 goto out_free; 951 952 while (count > 0) { 953 int this_len, retval, max_len; 954 955 this_len = mm->env_end - (mm->env_start + src); 956 957 if (this_len <= 0) 958 break; 959 960 max_len = (count > PAGE_SIZE) ? PAGE_SIZE : count; 961 this_len = (this_len > max_len) ? max_len : this_len; 962 963 retval = access_process_vm(task, (mm->env_start + src), 964 page, this_len, 0); 965 966 if (retval <= 0) { 967 ret = retval; 968 break; 969 } 970 971 if (copy_to_user(buf, page, retval)) { 972 ret = -EFAULT; 973 break; 974 } 975 976 ret += retval; 977 src += retval; 978 buf += retval; 979 count -= retval; 980 } 981 *ppos = src; 982 983 mmput(mm); 984 out_free: 985 free_page((unsigned long) page); 986 out: 987 put_task_struct(task); 988 out_no_task: 989 return ret; 990 } 991 992 static const struct file_operations proc_environ_operations = { 993 .read = environ_read, 994 }; 995 996 static ssize_t oom_adjust_read(struct file *file, char __user *buf, 997 size_t count, loff_t *ppos) 998 { 999 struct task_struct *task = get_proc_task(file->f_path.dentry->d_inode); 1000 char buffer[PROC_NUMBUF]; 1001 size_t len; 1002 int oom_adjust = OOM_DISABLE; 1003 unsigned long flags; 1004 1005 if (!task) 1006 return -ESRCH; 1007 1008 if (lock_task_sighand(task, &flags)) { 1009 oom_adjust = task->signal->oom_adj; 1010 unlock_task_sighand(task, &flags); 1011 } 1012 1013 put_task_struct(task); 1014 1015 len = snprintf(buffer, sizeof(buffer), "%i\n", oom_adjust); 1016 1017 return simple_read_from_buffer(buf, count, ppos, buffer, len); 1018 } 1019 1020 static ssize_t oom_adjust_write(struct file *file, const char __user *buf, 1021 size_t count, loff_t *ppos) 1022 { 1023 struct task_struct *task; 1024 char buffer[PROC_NUMBUF]; 1025 long oom_adjust; 1026 unsigned long flags; 1027 int err; 1028 1029 memset(buffer, 0, sizeof(buffer)); 1030 if (count > sizeof(buffer) - 1) 1031 count = sizeof(buffer) - 1; 1032 if (copy_from_user(buffer, buf, count)) 1033 return -EFAULT; 1034 1035 err = strict_strtol(strstrip(buffer), 0, &oom_adjust); 1036 if (err) 1037 return -EINVAL; 1038 if ((oom_adjust < OOM_ADJUST_MIN || oom_adjust > OOM_ADJUST_MAX) && 1039 oom_adjust != OOM_DISABLE) 1040 return -EINVAL; 1041 1042 task = get_proc_task(file->f_path.dentry->d_inode); 1043 if (!task) 1044 return -ESRCH; 1045 if (!lock_task_sighand(task, &flags)) { 1046 put_task_struct(task); 1047 return -ESRCH; 1048 } 1049 1050 if (oom_adjust < task->signal->oom_adj && !capable(CAP_SYS_RESOURCE)) { 1051 unlock_task_sighand(task, &flags); 1052 put_task_struct(task); 1053 return -EACCES; 1054 } 1055 1056 task->signal->oom_adj = oom_adjust; 1057 1058 unlock_task_sighand(task, &flags); 1059 put_task_struct(task); 1060 1061 return count; 1062 } 1063 1064 static const struct file_operations proc_oom_adjust_operations = { 1065 .read = oom_adjust_read, 1066 .write = oom_adjust_write, 1067 }; 1068 1069 #ifdef CONFIG_AUDITSYSCALL 1070 #define TMPBUFLEN 21 1071 static ssize_t proc_loginuid_read(struct file * file, char __user * buf, 1072 size_t count, loff_t *ppos) 1073 { 1074 struct inode * inode = file->f_path.dentry->d_inode; 1075 struct task_struct *task = get_proc_task(inode); 1076 ssize_t length; 1077 char tmpbuf[TMPBUFLEN]; 1078 1079 if (!task) 1080 return -ESRCH; 1081 length = scnprintf(tmpbuf, TMPBUFLEN, "%u", 1082 audit_get_loginuid(task)); 1083 put_task_struct(task); 1084 return simple_read_from_buffer(buf, count, ppos, tmpbuf, length); 1085 } 1086 1087 static ssize_t proc_loginuid_write(struct file * file, const char __user * buf, 1088 size_t count, loff_t *ppos) 1089 { 1090 struct inode * inode = file->f_path.dentry->d_inode; 1091 char *page, *tmp; 1092 ssize_t length; 1093 uid_t loginuid; 1094 1095 if (!capable(CAP_AUDIT_CONTROL)) 1096 return -EPERM; 1097 1098 if (current != pid_task(proc_pid(inode), PIDTYPE_PID)) 1099 return -EPERM; 1100 1101 if (count >= PAGE_SIZE) 1102 count = PAGE_SIZE - 1; 1103 1104 if (*ppos != 0) { 1105 /* No partial writes. */ 1106 return -EINVAL; 1107 } 1108 page = (char*)__get_free_page(GFP_TEMPORARY); 1109 if (!page) 1110 return -ENOMEM; 1111 length = -EFAULT; 1112 if (copy_from_user(page, buf, count)) 1113 goto out_free_page; 1114 1115 page[count] = '\0'; 1116 loginuid = simple_strtoul(page, &tmp, 10); 1117 if (tmp == page) { 1118 length = -EINVAL; 1119 goto out_free_page; 1120 1121 } 1122 length = audit_set_loginuid(current, loginuid); 1123 if (likely(length == 0)) 1124 length = count; 1125 1126 out_free_page: 1127 free_page((unsigned long) page); 1128 return length; 1129 } 1130 1131 static const struct file_operations proc_loginuid_operations = { 1132 .read = proc_loginuid_read, 1133 .write = proc_loginuid_write, 1134 }; 1135 1136 static ssize_t proc_sessionid_read(struct file * file, char __user * buf, 1137 size_t count, loff_t *ppos) 1138 { 1139 struct inode * inode = file->f_path.dentry->d_inode; 1140 struct task_struct *task = get_proc_task(inode); 1141 ssize_t length; 1142 char tmpbuf[TMPBUFLEN]; 1143 1144 if (!task) 1145 return -ESRCH; 1146 length = scnprintf(tmpbuf, TMPBUFLEN, "%u", 1147 audit_get_sessionid(task)); 1148 put_task_struct(task); 1149 return simple_read_from_buffer(buf, count, ppos, tmpbuf, length); 1150 } 1151 1152 static const struct file_operations proc_sessionid_operations = { 1153 .read = proc_sessionid_read, 1154 }; 1155 #endif 1156 1157 #ifdef CONFIG_FAULT_INJECTION 1158 static ssize_t proc_fault_inject_read(struct file * file, char __user * buf, 1159 size_t count, loff_t *ppos) 1160 { 1161 struct task_struct *task = get_proc_task(file->f_dentry->d_inode); 1162 char buffer[PROC_NUMBUF]; 1163 size_t len; 1164 int make_it_fail; 1165 1166 if (!task) 1167 return -ESRCH; 1168 make_it_fail = task->make_it_fail; 1169 put_task_struct(task); 1170 1171 len = snprintf(buffer, sizeof(buffer), "%i\n", make_it_fail); 1172 1173 return simple_read_from_buffer(buf, count, ppos, buffer, len); 1174 } 1175 1176 static ssize_t proc_fault_inject_write(struct file * file, 1177 const char __user * buf, size_t count, loff_t *ppos) 1178 { 1179 struct task_struct *task; 1180 char buffer[PROC_NUMBUF], *end; 1181 int make_it_fail; 1182 1183 if (!capable(CAP_SYS_RESOURCE)) 1184 return -EPERM; 1185 memset(buffer, 0, sizeof(buffer)); 1186 if (count > sizeof(buffer) - 1) 1187 count = sizeof(buffer) - 1; 1188 if (copy_from_user(buffer, buf, count)) 1189 return -EFAULT; 1190 make_it_fail = simple_strtol(strstrip(buffer), &end, 0); 1191 if (*end) 1192 return -EINVAL; 1193 task = get_proc_task(file->f_dentry->d_inode); 1194 if (!task) 1195 return -ESRCH; 1196 task->make_it_fail = make_it_fail; 1197 put_task_struct(task); 1198 1199 return count; 1200 } 1201 1202 static const struct file_operations proc_fault_inject_operations = { 1203 .read = proc_fault_inject_read, 1204 .write = proc_fault_inject_write, 1205 }; 1206 #endif 1207 1208 1209 #ifdef CONFIG_SCHED_DEBUG 1210 /* 1211 * Print out various scheduling related per-task fields: 1212 */ 1213 static int sched_show(struct seq_file *m, void *v) 1214 { 1215 struct inode *inode = m->private; 1216 struct task_struct *p; 1217 1218 p = get_proc_task(inode); 1219 if (!p) 1220 return -ESRCH; 1221 proc_sched_show_task(p, m); 1222 1223 put_task_struct(p); 1224 1225 return 0; 1226 } 1227 1228 static ssize_t 1229 sched_write(struct file *file, const char __user *buf, 1230 size_t count, loff_t *offset) 1231 { 1232 struct inode *inode = file->f_path.dentry->d_inode; 1233 struct task_struct *p; 1234 1235 p = get_proc_task(inode); 1236 if (!p) 1237 return -ESRCH; 1238 proc_sched_set_task(p); 1239 1240 put_task_struct(p); 1241 1242 return count; 1243 } 1244 1245 static int sched_open(struct inode *inode, struct file *filp) 1246 { 1247 int ret; 1248 1249 ret = single_open(filp, sched_show, NULL); 1250 if (!ret) { 1251 struct seq_file *m = filp->private_data; 1252 1253 m->private = inode; 1254 } 1255 return ret; 1256 } 1257 1258 static const struct file_operations proc_pid_sched_operations = { 1259 .open = sched_open, 1260 .read = seq_read, 1261 .write = sched_write, 1262 .llseek = seq_lseek, 1263 .release = single_release, 1264 }; 1265 1266 #endif 1267 1268 static ssize_t comm_write(struct file *file, const char __user *buf, 1269 size_t count, loff_t *offset) 1270 { 1271 struct inode *inode = file->f_path.dentry->d_inode; 1272 struct task_struct *p; 1273 char buffer[TASK_COMM_LEN]; 1274 1275 memset(buffer, 0, sizeof(buffer)); 1276 if (count > sizeof(buffer) - 1) 1277 count = sizeof(buffer) - 1; 1278 if (copy_from_user(buffer, buf, count)) 1279 return -EFAULT; 1280 1281 p = get_proc_task(inode); 1282 if (!p) 1283 return -ESRCH; 1284 1285 if (same_thread_group(current, p)) 1286 set_task_comm(p, buffer); 1287 else 1288 count = -EINVAL; 1289 1290 put_task_struct(p); 1291 1292 return count; 1293 } 1294 1295 static int comm_show(struct seq_file *m, void *v) 1296 { 1297 struct inode *inode = m->private; 1298 struct task_struct *p; 1299 1300 p = get_proc_task(inode); 1301 if (!p) 1302 return -ESRCH; 1303 1304 task_lock(p); 1305 seq_printf(m, "%s\n", p->comm); 1306 task_unlock(p); 1307 1308 put_task_struct(p); 1309 1310 return 0; 1311 } 1312 1313 static int comm_open(struct inode *inode, struct file *filp) 1314 { 1315 int ret; 1316 1317 ret = single_open(filp, comm_show, NULL); 1318 if (!ret) { 1319 struct seq_file *m = filp->private_data; 1320 1321 m->private = inode; 1322 } 1323 return ret; 1324 } 1325 1326 static const struct file_operations proc_pid_set_comm_operations = { 1327 .open = comm_open, 1328 .read = seq_read, 1329 .write = comm_write, 1330 .llseek = seq_lseek, 1331 .release = single_release, 1332 }; 1333 1334 /* 1335 * We added or removed a vma mapping the executable. The vmas are only mapped 1336 * during exec and are not mapped with the mmap system call. 1337 * Callers must hold down_write() on the mm's mmap_sem for these 1338 */ 1339 void added_exe_file_vma(struct mm_struct *mm) 1340 { 1341 mm->num_exe_file_vmas++; 1342 } 1343 1344 void removed_exe_file_vma(struct mm_struct *mm) 1345 { 1346 mm->num_exe_file_vmas--; 1347 if ((mm->num_exe_file_vmas == 0) && mm->exe_file){ 1348 fput(mm->exe_file); 1349 mm->exe_file = NULL; 1350 } 1351 1352 } 1353 1354 void set_mm_exe_file(struct mm_struct *mm, struct file *new_exe_file) 1355 { 1356 if (new_exe_file) 1357 get_file(new_exe_file); 1358 if (mm->exe_file) 1359 fput(mm->exe_file); 1360 mm->exe_file = new_exe_file; 1361 mm->num_exe_file_vmas = 0; 1362 } 1363 1364 struct file *get_mm_exe_file(struct mm_struct *mm) 1365 { 1366 struct file *exe_file; 1367 1368 /* We need mmap_sem to protect against races with removal of 1369 * VM_EXECUTABLE vmas */ 1370 down_read(&mm->mmap_sem); 1371 exe_file = mm->exe_file; 1372 if (exe_file) 1373 get_file(exe_file); 1374 up_read(&mm->mmap_sem); 1375 return exe_file; 1376 } 1377 1378 void dup_mm_exe_file(struct mm_struct *oldmm, struct mm_struct *newmm) 1379 { 1380 /* It's safe to write the exe_file pointer without exe_file_lock because 1381 * this is called during fork when the task is not yet in /proc */ 1382 newmm->exe_file = get_mm_exe_file(oldmm); 1383 } 1384 1385 static int proc_exe_link(struct inode *inode, struct path *exe_path) 1386 { 1387 struct task_struct *task; 1388 struct mm_struct *mm; 1389 struct file *exe_file; 1390 1391 task = get_proc_task(inode); 1392 if (!task) 1393 return -ENOENT; 1394 mm = get_task_mm(task); 1395 put_task_struct(task); 1396 if (!mm) 1397 return -ENOENT; 1398 exe_file = get_mm_exe_file(mm); 1399 mmput(mm); 1400 if (exe_file) { 1401 *exe_path = exe_file->f_path; 1402 path_get(&exe_file->f_path); 1403 fput(exe_file); 1404 return 0; 1405 } else 1406 return -ENOENT; 1407 } 1408 1409 static void *proc_pid_follow_link(struct dentry *dentry, struct nameidata *nd) 1410 { 1411 struct inode *inode = dentry->d_inode; 1412 int error = -EACCES; 1413 1414 /* We don't need a base pointer in the /proc filesystem */ 1415 path_put(&nd->path); 1416 1417 /* Are we allowed to snoop on the tasks file descriptors? */ 1418 if (!proc_fd_access_allowed(inode)) 1419 goto out; 1420 1421 error = PROC_I(inode)->op.proc_get_link(inode, &nd->path); 1422 out: 1423 return ERR_PTR(error); 1424 } 1425 1426 static int do_proc_readlink(struct path *path, char __user *buffer, int buflen) 1427 { 1428 char *tmp = (char*)__get_free_page(GFP_TEMPORARY); 1429 char *pathname; 1430 int len; 1431 1432 if (!tmp) 1433 return -ENOMEM; 1434 1435 pathname = d_path(path, tmp, PAGE_SIZE); 1436 len = PTR_ERR(pathname); 1437 if (IS_ERR(pathname)) 1438 goto out; 1439 len = tmp + PAGE_SIZE - 1 - pathname; 1440 1441 if (len > buflen) 1442 len = buflen; 1443 if (copy_to_user(buffer, pathname, len)) 1444 len = -EFAULT; 1445 out: 1446 free_page((unsigned long)tmp); 1447 return len; 1448 } 1449 1450 static int proc_pid_readlink(struct dentry * dentry, char __user * buffer, int buflen) 1451 { 1452 int error = -EACCES; 1453 struct inode *inode = dentry->d_inode; 1454 struct path path; 1455 1456 /* Are we allowed to snoop on the tasks file descriptors? */ 1457 if (!proc_fd_access_allowed(inode)) 1458 goto out; 1459 1460 error = PROC_I(inode)->op.proc_get_link(inode, &path); 1461 if (error) 1462 goto out; 1463 1464 error = do_proc_readlink(&path, buffer, buflen); 1465 path_put(&path); 1466 out: 1467 return error; 1468 } 1469 1470 static const struct inode_operations proc_pid_link_inode_operations = { 1471 .readlink = proc_pid_readlink, 1472 .follow_link = proc_pid_follow_link, 1473 .setattr = proc_setattr, 1474 }; 1475 1476 1477 /* building an inode */ 1478 1479 static int task_dumpable(struct task_struct *task) 1480 { 1481 int dumpable = 0; 1482 struct mm_struct *mm; 1483 1484 task_lock(task); 1485 mm = task->mm; 1486 if (mm) 1487 dumpable = get_dumpable(mm); 1488 task_unlock(task); 1489 if(dumpable == 1) 1490 return 1; 1491 return 0; 1492 } 1493 1494 1495 static struct inode *proc_pid_make_inode(struct super_block * sb, struct task_struct *task) 1496 { 1497 struct inode * inode; 1498 struct proc_inode *ei; 1499 const struct cred *cred; 1500 1501 /* We need a new inode */ 1502 1503 inode = new_inode(sb); 1504 if (!inode) 1505 goto out; 1506 1507 /* Common stuff */ 1508 ei = PROC_I(inode); 1509 inode->i_mtime = inode->i_atime = inode->i_ctime = CURRENT_TIME; 1510 inode->i_op = &proc_def_inode_operations; 1511 1512 /* 1513 * grab the reference to task. 1514 */ 1515 ei->pid = get_task_pid(task, PIDTYPE_PID); 1516 if (!ei->pid) 1517 goto out_unlock; 1518 1519 if (task_dumpable(task)) { 1520 rcu_read_lock(); 1521 cred = __task_cred(task); 1522 inode->i_uid = cred->euid; 1523 inode->i_gid = cred->egid; 1524 rcu_read_unlock(); 1525 } 1526 security_task_to_inode(task, inode); 1527 1528 out: 1529 return inode; 1530 1531 out_unlock: 1532 iput(inode); 1533 return NULL; 1534 } 1535 1536 static int pid_getattr(struct vfsmount *mnt, struct dentry *dentry, struct kstat *stat) 1537 { 1538 struct inode *inode = dentry->d_inode; 1539 struct task_struct *task; 1540 const struct cred *cred; 1541 1542 generic_fillattr(inode, stat); 1543 1544 rcu_read_lock(); 1545 stat->uid = 0; 1546 stat->gid = 0; 1547 task = pid_task(proc_pid(inode), PIDTYPE_PID); 1548 if (task) { 1549 if ((inode->i_mode == (S_IFDIR|S_IRUGO|S_IXUGO)) || 1550 task_dumpable(task)) { 1551 cred = __task_cred(task); 1552 stat->uid = cred->euid; 1553 stat->gid = cred->egid; 1554 } 1555 } 1556 rcu_read_unlock(); 1557 return 0; 1558 } 1559 1560 /* dentry stuff */ 1561 1562 /* 1563 * Exceptional case: normally we are not allowed to unhash a busy 1564 * directory. In this case, however, we can do it - no aliasing problems 1565 * due to the way we treat inodes. 1566 * 1567 * Rewrite the inode's ownerships here because the owning task may have 1568 * performed a setuid(), etc. 1569 * 1570 * Before the /proc/pid/status file was created the only way to read 1571 * the effective uid of a /process was to stat /proc/pid. Reading 1572 * /proc/pid/status is slow enough that procps and other packages 1573 * kept stating /proc/pid. To keep the rules in /proc simple I have 1574 * made this apply to all per process world readable and executable 1575 * directories. 1576 */ 1577 static int pid_revalidate(struct dentry *dentry, struct nameidata *nd) 1578 { 1579 struct inode *inode = dentry->d_inode; 1580 struct task_struct *task = get_proc_task(inode); 1581 const struct cred *cred; 1582 1583 if (task) { 1584 if ((inode->i_mode == (S_IFDIR|S_IRUGO|S_IXUGO)) || 1585 task_dumpable(task)) { 1586 rcu_read_lock(); 1587 cred = __task_cred(task); 1588 inode->i_uid = cred->euid; 1589 inode->i_gid = cred->egid; 1590 rcu_read_unlock(); 1591 } else { 1592 inode->i_uid = 0; 1593 inode->i_gid = 0; 1594 } 1595 inode->i_mode &= ~(S_ISUID | S_ISGID); 1596 security_task_to_inode(task, inode); 1597 put_task_struct(task); 1598 return 1; 1599 } 1600 d_drop(dentry); 1601 return 0; 1602 } 1603 1604 static int pid_delete_dentry(struct dentry * dentry) 1605 { 1606 /* Is the task we represent dead? 1607 * If so, then don't put the dentry on the lru list, 1608 * kill it immediately. 1609 */ 1610 return !proc_pid(dentry->d_inode)->tasks[PIDTYPE_PID].first; 1611 } 1612 1613 static const struct dentry_operations pid_dentry_operations = 1614 { 1615 .d_revalidate = pid_revalidate, 1616 .d_delete = pid_delete_dentry, 1617 }; 1618 1619 /* Lookups */ 1620 1621 typedef struct dentry *instantiate_t(struct inode *, struct dentry *, 1622 struct task_struct *, const void *); 1623 1624 /* 1625 * Fill a directory entry. 1626 * 1627 * If possible create the dcache entry and derive our inode number and 1628 * file type from dcache entry. 1629 * 1630 * Since all of the proc inode numbers are dynamically generated, the inode 1631 * numbers do not exist until the inode is cache. This means creating the 1632 * the dcache entry in readdir is necessary to keep the inode numbers 1633 * reported by readdir in sync with the inode numbers reported 1634 * by stat. 1635 */ 1636 static int proc_fill_cache(struct file *filp, void *dirent, filldir_t filldir, 1637 char *name, int len, 1638 instantiate_t instantiate, struct task_struct *task, const void *ptr) 1639 { 1640 struct dentry *child, *dir = filp->f_path.dentry; 1641 struct inode *inode; 1642 struct qstr qname; 1643 ino_t ino = 0; 1644 unsigned type = DT_UNKNOWN; 1645 1646 qname.name = name; 1647 qname.len = len; 1648 qname.hash = full_name_hash(name, len); 1649 1650 child = d_lookup(dir, &qname); 1651 if (!child) { 1652 struct dentry *new; 1653 new = d_alloc(dir, &qname); 1654 if (new) { 1655 child = instantiate(dir->d_inode, new, task, ptr); 1656 if (child) 1657 dput(new); 1658 else 1659 child = new; 1660 } 1661 } 1662 if (!child || IS_ERR(child) || !child->d_inode) 1663 goto end_instantiate; 1664 inode = child->d_inode; 1665 if (inode) { 1666 ino = inode->i_ino; 1667 type = inode->i_mode >> 12; 1668 } 1669 dput(child); 1670 end_instantiate: 1671 if (!ino) 1672 ino = find_inode_number(dir, &qname); 1673 if (!ino) 1674 ino = 1; 1675 return filldir(dirent, name, len, filp->f_pos, ino, type); 1676 } 1677 1678 static unsigned name_to_int(struct dentry *dentry) 1679 { 1680 const char *name = dentry->d_name.name; 1681 int len = dentry->d_name.len; 1682 unsigned n = 0; 1683 1684 if (len > 1 && *name == '0') 1685 goto out; 1686 while (len-- > 0) { 1687 unsigned c = *name++ - '0'; 1688 if (c > 9) 1689 goto out; 1690 if (n >= (~0U-9)/10) 1691 goto out; 1692 n *= 10; 1693 n += c; 1694 } 1695 return n; 1696 out: 1697 return ~0U; 1698 } 1699 1700 #define PROC_FDINFO_MAX 64 1701 1702 static int proc_fd_info(struct inode *inode, struct path *path, char *info) 1703 { 1704 struct task_struct *task = get_proc_task(inode); 1705 struct files_struct *files = NULL; 1706 struct file *file; 1707 int fd = proc_fd(inode); 1708 1709 if (task) { 1710 files = get_files_struct(task); 1711 put_task_struct(task); 1712 } 1713 if (files) { 1714 /* 1715 * We are not taking a ref to the file structure, so we must 1716 * hold ->file_lock. 1717 */ 1718 spin_lock(&files->file_lock); 1719 file = fcheck_files(files, fd); 1720 if (file) { 1721 if (path) { 1722 *path = file->f_path; 1723 path_get(&file->f_path); 1724 } 1725 if (info) 1726 snprintf(info, PROC_FDINFO_MAX, 1727 "pos:\t%lli\n" 1728 "flags:\t0%o\n", 1729 (long long) file->f_pos, 1730 file->f_flags); 1731 spin_unlock(&files->file_lock); 1732 put_files_struct(files); 1733 return 0; 1734 } 1735 spin_unlock(&files->file_lock); 1736 put_files_struct(files); 1737 } 1738 return -ENOENT; 1739 } 1740 1741 static int proc_fd_link(struct inode *inode, struct path *path) 1742 { 1743 return proc_fd_info(inode, path, NULL); 1744 } 1745 1746 static int tid_fd_revalidate(struct dentry *dentry, struct nameidata *nd) 1747 { 1748 struct inode *inode = dentry->d_inode; 1749 struct task_struct *task = get_proc_task(inode); 1750 int fd = proc_fd(inode); 1751 struct files_struct *files; 1752 const struct cred *cred; 1753 1754 if (task) { 1755 files = get_files_struct(task); 1756 if (files) { 1757 rcu_read_lock(); 1758 if (fcheck_files(files, fd)) { 1759 rcu_read_unlock(); 1760 put_files_struct(files); 1761 if (task_dumpable(task)) { 1762 rcu_read_lock(); 1763 cred = __task_cred(task); 1764 inode->i_uid = cred->euid; 1765 inode->i_gid = cred->egid; 1766 rcu_read_unlock(); 1767 } else { 1768 inode->i_uid = 0; 1769 inode->i_gid = 0; 1770 } 1771 inode->i_mode &= ~(S_ISUID | S_ISGID); 1772 security_task_to_inode(task, inode); 1773 put_task_struct(task); 1774 return 1; 1775 } 1776 rcu_read_unlock(); 1777 put_files_struct(files); 1778 } 1779 put_task_struct(task); 1780 } 1781 d_drop(dentry); 1782 return 0; 1783 } 1784 1785 static const struct dentry_operations tid_fd_dentry_operations = 1786 { 1787 .d_revalidate = tid_fd_revalidate, 1788 .d_delete = pid_delete_dentry, 1789 }; 1790 1791 static struct dentry *proc_fd_instantiate(struct inode *dir, 1792 struct dentry *dentry, struct task_struct *task, const void *ptr) 1793 { 1794 unsigned fd = *(const unsigned *)ptr; 1795 struct file *file; 1796 struct files_struct *files; 1797 struct inode *inode; 1798 struct proc_inode *ei; 1799 struct dentry *error = ERR_PTR(-ENOENT); 1800 1801 inode = proc_pid_make_inode(dir->i_sb, task); 1802 if (!inode) 1803 goto out; 1804 ei = PROC_I(inode); 1805 ei->fd = fd; 1806 files = get_files_struct(task); 1807 if (!files) 1808 goto out_iput; 1809 inode->i_mode = S_IFLNK; 1810 1811 /* 1812 * We are not taking a ref to the file structure, so we must 1813 * hold ->file_lock. 1814 */ 1815 spin_lock(&files->file_lock); 1816 file = fcheck_files(files, fd); 1817 if (!file) 1818 goto out_unlock; 1819 if (file->f_mode & FMODE_READ) 1820 inode->i_mode |= S_IRUSR | S_IXUSR; 1821 if (file->f_mode & FMODE_WRITE) 1822 inode->i_mode |= S_IWUSR | S_IXUSR; 1823 spin_unlock(&files->file_lock); 1824 put_files_struct(files); 1825 1826 inode->i_op = &proc_pid_link_inode_operations; 1827 inode->i_size = 64; 1828 ei->op.proc_get_link = proc_fd_link; 1829 dentry->d_op = &tid_fd_dentry_operations; 1830 d_add(dentry, inode); 1831 /* Close the race of the process dying before we return the dentry */ 1832 if (tid_fd_revalidate(dentry, NULL)) 1833 error = NULL; 1834 1835 out: 1836 return error; 1837 out_unlock: 1838 spin_unlock(&files->file_lock); 1839 put_files_struct(files); 1840 out_iput: 1841 iput(inode); 1842 goto out; 1843 } 1844 1845 static struct dentry *proc_lookupfd_common(struct inode *dir, 1846 struct dentry *dentry, 1847 instantiate_t instantiate) 1848 { 1849 struct task_struct *task = get_proc_task(dir); 1850 unsigned fd = name_to_int(dentry); 1851 struct dentry *result = ERR_PTR(-ENOENT); 1852 1853 if (!task) 1854 goto out_no_task; 1855 if (fd == ~0U) 1856 goto out; 1857 1858 result = instantiate(dir, dentry, task, &fd); 1859 out: 1860 put_task_struct(task); 1861 out_no_task: 1862 return result; 1863 } 1864 1865 static int proc_readfd_common(struct file * filp, void * dirent, 1866 filldir_t filldir, instantiate_t instantiate) 1867 { 1868 struct dentry *dentry = filp->f_path.dentry; 1869 struct inode *inode = dentry->d_inode; 1870 struct task_struct *p = get_proc_task(inode); 1871 unsigned int fd, ino; 1872 int retval; 1873 struct files_struct * files; 1874 1875 retval = -ENOENT; 1876 if (!p) 1877 goto out_no_task; 1878 retval = 0; 1879 1880 fd = filp->f_pos; 1881 switch (fd) { 1882 case 0: 1883 if (filldir(dirent, ".", 1, 0, inode->i_ino, DT_DIR) < 0) 1884 goto out; 1885 filp->f_pos++; 1886 case 1: 1887 ino = parent_ino(dentry); 1888 if (filldir(dirent, "..", 2, 1, ino, DT_DIR) < 0) 1889 goto out; 1890 filp->f_pos++; 1891 default: 1892 files = get_files_struct(p); 1893 if (!files) 1894 goto out; 1895 rcu_read_lock(); 1896 for (fd = filp->f_pos-2; 1897 fd < files_fdtable(files)->max_fds; 1898 fd++, filp->f_pos++) { 1899 char name[PROC_NUMBUF]; 1900 int len; 1901 1902 if (!fcheck_files(files, fd)) 1903 continue; 1904 rcu_read_unlock(); 1905 1906 len = snprintf(name, sizeof(name), "%d", fd); 1907 if (proc_fill_cache(filp, dirent, filldir, 1908 name, len, instantiate, 1909 p, &fd) < 0) { 1910 rcu_read_lock(); 1911 break; 1912 } 1913 rcu_read_lock(); 1914 } 1915 rcu_read_unlock(); 1916 put_files_struct(files); 1917 } 1918 out: 1919 put_task_struct(p); 1920 out_no_task: 1921 return retval; 1922 } 1923 1924 static struct dentry *proc_lookupfd(struct inode *dir, struct dentry *dentry, 1925 struct nameidata *nd) 1926 { 1927 return proc_lookupfd_common(dir, dentry, proc_fd_instantiate); 1928 } 1929 1930 static int proc_readfd(struct file *filp, void *dirent, filldir_t filldir) 1931 { 1932 return proc_readfd_common(filp, dirent, filldir, proc_fd_instantiate); 1933 } 1934 1935 static ssize_t proc_fdinfo_read(struct file *file, char __user *buf, 1936 size_t len, loff_t *ppos) 1937 { 1938 char tmp[PROC_FDINFO_MAX]; 1939 int err = proc_fd_info(file->f_path.dentry->d_inode, NULL, tmp); 1940 if (!err) 1941 err = simple_read_from_buffer(buf, len, ppos, tmp, strlen(tmp)); 1942 return err; 1943 } 1944 1945 static const struct file_operations proc_fdinfo_file_operations = { 1946 .open = nonseekable_open, 1947 .read = proc_fdinfo_read, 1948 }; 1949 1950 static const struct file_operations proc_fd_operations = { 1951 .read = generic_read_dir, 1952 .readdir = proc_readfd, 1953 }; 1954 1955 /* 1956 * /proc/pid/fd needs a special permission handler so that a process can still 1957 * access /proc/self/fd after it has executed a setuid(). 1958 */ 1959 static int proc_fd_permission(struct inode *inode, int mask) 1960 { 1961 int rv; 1962 1963 rv = generic_permission(inode, mask, NULL); 1964 if (rv == 0) 1965 return 0; 1966 if (task_pid(current) == proc_pid(inode)) 1967 rv = 0; 1968 return rv; 1969 } 1970 1971 /* 1972 * proc directories can do almost nothing.. 1973 */ 1974 static const struct inode_operations proc_fd_inode_operations = { 1975 .lookup = proc_lookupfd, 1976 .permission = proc_fd_permission, 1977 .setattr = proc_setattr, 1978 }; 1979 1980 static struct dentry *proc_fdinfo_instantiate(struct inode *dir, 1981 struct dentry *dentry, struct task_struct *task, const void *ptr) 1982 { 1983 unsigned fd = *(unsigned *)ptr; 1984 struct inode *inode; 1985 struct proc_inode *ei; 1986 struct dentry *error = ERR_PTR(-ENOENT); 1987 1988 inode = proc_pid_make_inode(dir->i_sb, task); 1989 if (!inode) 1990 goto out; 1991 ei = PROC_I(inode); 1992 ei->fd = fd; 1993 inode->i_mode = S_IFREG | S_IRUSR; 1994 inode->i_fop = &proc_fdinfo_file_operations; 1995 dentry->d_op = &tid_fd_dentry_operations; 1996 d_add(dentry, inode); 1997 /* Close the race of the process dying before we return the dentry */ 1998 if (tid_fd_revalidate(dentry, NULL)) 1999 error = NULL; 2000 2001 out: 2002 return error; 2003 } 2004 2005 static struct dentry *proc_lookupfdinfo(struct inode *dir, 2006 struct dentry *dentry, 2007 struct nameidata *nd) 2008 { 2009 return proc_lookupfd_common(dir, dentry, proc_fdinfo_instantiate); 2010 } 2011 2012 static int proc_readfdinfo(struct file *filp, void *dirent, filldir_t filldir) 2013 { 2014 return proc_readfd_common(filp, dirent, filldir, 2015 proc_fdinfo_instantiate); 2016 } 2017 2018 static const struct file_operations proc_fdinfo_operations = { 2019 .read = generic_read_dir, 2020 .readdir = proc_readfdinfo, 2021 }; 2022 2023 /* 2024 * proc directories can do almost nothing.. 2025 */ 2026 static const struct inode_operations proc_fdinfo_inode_operations = { 2027 .lookup = proc_lookupfdinfo, 2028 .setattr = proc_setattr, 2029 }; 2030 2031 2032 static struct dentry *proc_pident_instantiate(struct inode *dir, 2033 struct dentry *dentry, struct task_struct *task, const void *ptr) 2034 { 2035 const struct pid_entry *p = ptr; 2036 struct inode *inode; 2037 struct proc_inode *ei; 2038 struct dentry *error = ERR_PTR(-ENOENT); 2039 2040 inode = proc_pid_make_inode(dir->i_sb, task); 2041 if (!inode) 2042 goto out; 2043 2044 ei = PROC_I(inode); 2045 inode->i_mode = p->mode; 2046 if (S_ISDIR(inode->i_mode)) 2047 inode->i_nlink = 2; /* Use getattr to fix if necessary */ 2048 if (p->iop) 2049 inode->i_op = p->iop; 2050 if (p->fop) 2051 inode->i_fop = p->fop; 2052 ei->op = p->op; 2053 dentry->d_op = &pid_dentry_operations; 2054 d_add(dentry, inode); 2055 /* Close the race of the process dying before we return the dentry */ 2056 if (pid_revalidate(dentry, NULL)) 2057 error = NULL; 2058 out: 2059 return error; 2060 } 2061 2062 static struct dentry *proc_pident_lookup(struct inode *dir, 2063 struct dentry *dentry, 2064 const struct pid_entry *ents, 2065 unsigned int nents) 2066 { 2067 struct dentry *error; 2068 struct task_struct *task = get_proc_task(dir); 2069 const struct pid_entry *p, *last; 2070 2071 error = ERR_PTR(-ENOENT); 2072 2073 if (!task) 2074 goto out_no_task; 2075 2076 /* 2077 * Yes, it does not scale. And it should not. Don't add 2078 * new entries into /proc/<tgid>/ without very good reasons. 2079 */ 2080 last = &ents[nents - 1]; 2081 for (p = ents; p <= last; p++) { 2082 if (p->len != dentry->d_name.len) 2083 continue; 2084 if (!memcmp(dentry->d_name.name, p->name, p->len)) 2085 break; 2086 } 2087 if (p > last) 2088 goto out; 2089 2090 error = proc_pident_instantiate(dir, dentry, task, p); 2091 out: 2092 put_task_struct(task); 2093 out_no_task: 2094 return error; 2095 } 2096 2097 static int proc_pident_fill_cache(struct file *filp, void *dirent, 2098 filldir_t filldir, struct task_struct *task, const struct pid_entry *p) 2099 { 2100 return proc_fill_cache(filp, dirent, filldir, p->name, p->len, 2101 proc_pident_instantiate, task, p); 2102 } 2103 2104 static int proc_pident_readdir(struct file *filp, 2105 void *dirent, filldir_t filldir, 2106 const struct pid_entry *ents, unsigned int nents) 2107 { 2108 int i; 2109 struct dentry *dentry = filp->f_path.dentry; 2110 struct inode *inode = dentry->d_inode; 2111 struct task_struct *task = get_proc_task(inode); 2112 const struct pid_entry *p, *last; 2113 ino_t ino; 2114 int ret; 2115 2116 ret = -ENOENT; 2117 if (!task) 2118 goto out_no_task; 2119 2120 ret = 0; 2121 i = filp->f_pos; 2122 switch (i) { 2123 case 0: 2124 ino = inode->i_ino; 2125 if (filldir(dirent, ".", 1, i, ino, DT_DIR) < 0) 2126 goto out; 2127 i++; 2128 filp->f_pos++; 2129 /* fall through */ 2130 case 1: 2131 ino = parent_ino(dentry); 2132 if (filldir(dirent, "..", 2, i, ino, DT_DIR) < 0) 2133 goto out; 2134 i++; 2135 filp->f_pos++; 2136 /* fall through */ 2137 default: 2138 i -= 2; 2139 if (i >= nents) { 2140 ret = 1; 2141 goto out; 2142 } 2143 p = ents + i; 2144 last = &ents[nents - 1]; 2145 while (p <= last) { 2146 if (proc_pident_fill_cache(filp, dirent, filldir, task, p) < 0) 2147 goto out; 2148 filp->f_pos++; 2149 p++; 2150 } 2151 } 2152 2153 ret = 1; 2154 out: 2155 put_task_struct(task); 2156 out_no_task: 2157 return ret; 2158 } 2159 2160 #ifdef CONFIG_SECURITY 2161 static ssize_t proc_pid_attr_read(struct file * file, char __user * buf, 2162 size_t count, loff_t *ppos) 2163 { 2164 struct inode * inode = file->f_path.dentry->d_inode; 2165 char *p = NULL; 2166 ssize_t length; 2167 struct task_struct *task = get_proc_task(inode); 2168 2169 if (!task) 2170 return -ESRCH; 2171 2172 length = security_getprocattr(task, 2173 (char*)file->f_path.dentry->d_name.name, 2174 &p); 2175 put_task_struct(task); 2176 if (length > 0) 2177 length = simple_read_from_buffer(buf, count, ppos, p, length); 2178 kfree(p); 2179 return length; 2180 } 2181 2182 static ssize_t proc_pid_attr_write(struct file * file, const char __user * buf, 2183 size_t count, loff_t *ppos) 2184 { 2185 struct inode * inode = file->f_path.dentry->d_inode; 2186 char *page; 2187 ssize_t length; 2188 struct task_struct *task = get_proc_task(inode); 2189 2190 length = -ESRCH; 2191 if (!task) 2192 goto out_no_task; 2193 if (count > PAGE_SIZE) 2194 count = PAGE_SIZE; 2195 2196 /* No partial writes. */ 2197 length = -EINVAL; 2198 if (*ppos != 0) 2199 goto out; 2200 2201 length = -ENOMEM; 2202 page = (char*)__get_free_page(GFP_TEMPORARY); 2203 if (!page) 2204 goto out; 2205 2206 length = -EFAULT; 2207 if (copy_from_user(page, buf, count)) 2208 goto out_free; 2209 2210 /* Guard against adverse ptrace interaction */ 2211 length = mutex_lock_interruptible(&task->cred_guard_mutex); 2212 if (length < 0) 2213 goto out_free; 2214 2215 length = security_setprocattr(task, 2216 (char*)file->f_path.dentry->d_name.name, 2217 (void*)page, count); 2218 mutex_unlock(&task->cred_guard_mutex); 2219 out_free: 2220 free_page((unsigned long) page); 2221 out: 2222 put_task_struct(task); 2223 out_no_task: 2224 return length; 2225 } 2226 2227 static const struct file_operations proc_pid_attr_operations = { 2228 .read = proc_pid_attr_read, 2229 .write = proc_pid_attr_write, 2230 }; 2231 2232 static const struct pid_entry attr_dir_stuff[] = { 2233 REG("current", S_IRUGO|S_IWUGO, proc_pid_attr_operations), 2234 REG("prev", S_IRUGO, proc_pid_attr_operations), 2235 REG("exec", S_IRUGO|S_IWUGO, proc_pid_attr_operations), 2236 REG("fscreate", S_IRUGO|S_IWUGO, proc_pid_attr_operations), 2237 REG("keycreate", S_IRUGO|S_IWUGO, proc_pid_attr_operations), 2238 REG("sockcreate", S_IRUGO|S_IWUGO, proc_pid_attr_operations), 2239 }; 2240 2241 static int proc_attr_dir_readdir(struct file * filp, 2242 void * dirent, filldir_t filldir) 2243 { 2244 return proc_pident_readdir(filp,dirent,filldir, 2245 attr_dir_stuff,ARRAY_SIZE(attr_dir_stuff)); 2246 } 2247 2248 static const struct file_operations proc_attr_dir_operations = { 2249 .read = generic_read_dir, 2250 .readdir = proc_attr_dir_readdir, 2251 }; 2252 2253 static struct dentry *proc_attr_dir_lookup(struct inode *dir, 2254 struct dentry *dentry, struct nameidata *nd) 2255 { 2256 return proc_pident_lookup(dir, dentry, 2257 attr_dir_stuff, ARRAY_SIZE(attr_dir_stuff)); 2258 } 2259 2260 static const struct inode_operations proc_attr_dir_inode_operations = { 2261 .lookup = proc_attr_dir_lookup, 2262 .getattr = pid_getattr, 2263 .setattr = proc_setattr, 2264 }; 2265 2266 #endif 2267 2268 #ifdef CONFIG_ELF_CORE 2269 static ssize_t proc_coredump_filter_read(struct file *file, char __user *buf, 2270 size_t count, loff_t *ppos) 2271 { 2272 struct task_struct *task = get_proc_task(file->f_dentry->d_inode); 2273 struct mm_struct *mm; 2274 char buffer[PROC_NUMBUF]; 2275 size_t len; 2276 int ret; 2277 2278 if (!task) 2279 return -ESRCH; 2280 2281 ret = 0; 2282 mm = get_task_mm(task); 2283 if (mm) { 2284 len = snprintf(buffer, sizeof(buffer), "%08lx\n", 2285 ((mm->flags & MMF_DUMP_FILTER_MASK) >> 2286 MMF_DUMP_FILTER_SHIFT)); 2287 mmput(mm); 2288 ret = simple_read_from_buffer(buf, count, ppos, buffer, len); 2289 } 2290 2291 put_task_struct(task); 2292 2293 return ret; 2294 } 2295 2296 static ssize_t proc_coredump_filter_write(struct file *file, 2297 const char __user *buf, 2298 size_t count, 2299 loff_t *ppos) 2300 { 2301 struct task_struct *task; 2302 struct mm_struct *mm; 2303 char buffer[PROC_NUMBUF], *end; 2304 unsigned int val; 2305 int ret; 2306 int i; 2307 unsigned long mask; 2308 2309 ret = -EFAULT; 2310 memset(buffer, 0, sizeof(buffer)); 2311 if (count > sizeof(buffer) - 1) 2312 count = sizeof(buffer) - 1; 2313 if (copy_from_user(buffer, buf, count)) 2314 goto out_no_task; 2315 2316 ret = -EINVAL; 2317 val = (unsigned int)simple_strtoul(buffer, &end, 0); 2318 if (*end == '\n') 2319 end++; 2320 if (end - buffer == 0) 2321 goto out_no_task; 2322 2323 ret = -ESRCH; 2324 task = get_proc_task(file->f_dentry->d_inode); 2325 if (!task) 2326 goto out_no_task; 2327 2328 ret = end - buffer; 2329 mm = get_task_mm(task); 2330 if (!mm) 2331 goto out_no_mm; 2332 2333 for (i = 0, mask = 1; i < MMF_DUMP_FILTER_BITS; i++, mask <<= 1) { 2334 if (val & mask) 2335 set_bit(i + MMF_DUMP_FILTER_SHIFT, &mm->flags); 2336 else 2337 clear_bit(i + MMF_DUMP_FILTER_SHIFT, &mm->flags); 2338 } 2339 2340 mmput(mm); 2341 out_no_mm: 2342 put_task_struct(task); 2343 out_no_task: 2344 return ret; 2345 } 2346 2347 static const struct file_operations proc_coredump_filter_operations = { 2348 .read = proc_coredump_filter_read, 2349 .write = proc_coredump_filter_write, 2350 }; 2351 #endif 2352 2353 /* 2354 * /proc/self: 2355 */ 2356 static int proc_self_readlink(struct dentry *dentry, char __user *buffer, 2357 int buflen) 2358 { 2359 struct pid_namespace *ns = dentry->d_sb->s_fs_info; 2360 pid_t tgid = task_tgid_nr_ns(current, ns); 2361 char tmp[PROC_NUMBUF]; 2362 if (!tgid) 2363 return -ENOENT; 2364 sprintf(tmp, "%d", tgid); 2365 return vfs_readlink(dentry,buffer,buflen,tmp); 2366 } 2367 2368 static void *proc_self_follow_link(struct dentry *dentry, struct nameidata *nd) 2369 { 2370 struct pid_namespace *ns = dentry->d_sb->s_fs_info; 2371 pid_t tgid = task_tgid_nr_ns(current, ns); 2372 char tmp[PROC_NUMBUF]; 2373 if (!tgid) 2374 return ERR_PTR(-ENOENT); 2375 sprintf(tmp, "%d", task_tgid_nr_ns(current, ns)); 2376 return ERR_PTR(vfs_follow_link(nd,tmp)); 2377 } 2378 2379 static const struct inode_operations proc_self_inode_operations = { 2380 .readlink = proc_self_readlink, 2381 .follow_link = proc_self_follow_link, 2382 }; 2383 2384 /* 2385 * proc base 2386 * 2387 * These are the directory entries in the root directory of /proc 2388 * that properly belong to the /proc filesystem, as they describe 2389 * describe something that is process related. 2390 */ 2391 static const struct pid_entry proc_base_stuff[] = { 2392 NOD("self", S_IFLNK|S_IRWXUGO, 2393 &proc_self_inode_operations, NULL, {}), 2394 }; 2395 2396 /* 2397 * Exceptional case: normally we are not allowed to unhash a busy 2398 * directory. In this case, however, we can do it - no aliasing problems 2399 * due to the way we treat inodes. 2400 */ 2401 static int proc_base_revalidate(struct dentry *dentry, struct nameidata *nd) 2402 { 2403 struct inode *inode = dentry->d_inode; 2404 struct task_struct *task = get_proc_task(inode); 2405 if (task) { 2406 put_task_struct(task); 2407 return 1; 2408 } 2409 d_drop(dentry); 2410 return 0; 2411 } 2412 2413 static const struct dentry_operations proc_base_dentry_operations = 2414 { 2415 .d_revalidate = proc_base_revalidate, 2416 .d_delete = pid_delete_dentry, 2417 }; 2418 2419 static struct dentry *proc_base_instantiate(struct inode *dir, 2420 struct dentry *dentry, struct task_struct *task, const void *ptr) 2421 { 2422 const struct pid_entry *p = ptr; 2423 struct inode *inode; 2424 struct proc_inode *ei; 2425 struct dentry *error = ERR_PTR(-EINVAL); 2426 2427 /* Allocate the inode */ 2428 error = ERR_PTR(-ENOMEM); 2429 inode = new_inode(dir->i_sb); 2430 if (!inode) 2431 goto out; 2432 2433 /* Initialize the inode */ 2434 ei = PROC_I(inode); 2435 inode->i_mtime = inode->i_atime = inode->i_ctime = CURRENT_TIME; 2436 2437 /* 2438 * grab the reference to the task. 2439 */ 2440 ei->pid = get_task_pid(task, PIDTYPE_PID); 2441 if (!ei->pid) 2442 goto out_iput; 2443 2444 inode->i_mode = p->mode; 2445 if (S_ISDIR(inode->i_mode)) 2446 inode->i_nlink = 2; 2447 if (S_ISLNK(inode->i_mode)) 2448 inode->i_size = 64; 2449 if (p->iop) 2450 inode->i_op = p->iop; 2451 if (p->fop) 2452 inode->i_fop = p->fop; 2453 ei->op = p->op; 2454 dentry->d_op = &proc_base_dentry_operations; 2455 d_add(dentry, inode); 2456 error = NULL; 2457 out: 2458 return error; 2459 out_iput: 2460 iput(inode); 2461 goto out; 2462 } 2463 2464 static struct dentry *proc_base_lookup(struct inode *dir, struct dentry *dentry) 2465 { 2466 struct dentry *error; 2467 struct task_struct *task = get_proc_task(dir); 2468 const struct pid_entry *p, *last; 2469 2470 error = ERR_PTR(-ENOENT); 2471 2472 if (!task) 2473 goto out_no_task; 2474 2475 /* Lookup the directory entry */ 2476 last = &proc_base_stuff[ARRAY_SIZE(proc_base_stuff) - 1]; 2477 for (p = proc_base_stuff; p <= last; p++) { 2478 if (p->len != dentry->d_name.len) 2479 continue; 2480 if (!memcmp(dentry->d_name.name, p->name, p->len)) 2481 break; 2482 } 2483 if (p > last) 2484 goto out; 2485 2486 error = proc_base_instantiate(dir, dentry, task, p); 2487 2488 out: 2489 put_task_struct(task); 2490 out_no_task: 2491 return error; 2492 } 2493 2494 static int proc_base_fill_cache(struct file *filp, void *dirent, 2495 filldir_t filldir, struct task_struct *task, const struct pid_entry *p) 2496 { 2497 return proc_fill_cache(filp, dirent, filldir, p->name, p->len, 2498 proc_base_instantiate, task, p); 2499 } 2500 2501 #ifdef CONFIG_TASK_IO_ACCOUNTING 2502 static int do_io_accounting(struct task_struct *task, char *buffer, int whole) 2503 { 2504 struct task_io_accounting acct = task->ioac; 2505 unsigned long flags; 2506 2507 if (whole && lock_task_sighand(task, &flags)) { 2508 struct task_struct *t = task; 2509 2510 task_io_accounting_add(&acct, &task->signal->ioac); 2511 while_each_thread(task, t) 2512 task_io_accounting_add(&acct, &t->ioac); 2513 2514 unlock_task_sighand(task, &flags); 2515 } 2516 return sprintf(buffer, 2517 "rchar: %llu\n" 2518 "wchar: %llu\n" 2519 "syscr: %llu\n" 2520 "syscw: %llu\n" 2521 "read_bytes: %llu\n" 2522 "write_bytes: %llu\n" 2523 "cancelled_write_bytes: %llu\n", 2524 (unsigned long long)acct.rchar, 2525 (unsigned long long)acct.wchar, 2526 (unsigned long long)acct.syscr, 2527 (unsigned long long)acct.syscw, 2528 (unsigned long long)acct.read_bytes, 2529 (unsigned long long)acct.write_bytes, 2530 (unsigned long long)acct.cancelled_write_bytes); 2531 } 2532 2533 static int proc_tid_io_accounting(struct task_struct *task, char *buffer) 2534 { 2535 return do_io_accounting(task, buffer, 0); 2536 } 2537 2538 static int proc_tgid_io_accounting(struct task_struct *task, char *buffer) 2539 { 2540 return do_io_accounting(task, buffer, 1); 2541 } 2542 #endif /* CONFIG_TASK_IO_ACCOUNTING */ 2543 2544 static int proc_pid_personality(struct seq_file *m, struct pid_namespace *ns, 2545 struct pid *pid, struct task_struct *task) 2546 { 2547 seq_printf(m, "%08x\n", task->personality); 2548 return 0; 2549 } 2550 2551 /* 2552 * Thread groups 2553 */ 2554 static const struct file_operations proc_task_operations; 2555 static const struct inode_operations proc_task_inode_operations; 2556 2557 static const struct pid_entry tgid_base_stuff[] = { 2558 DIR("task", S_IRUGO|S_IXUGO, proc_task_inode_operations, proc_task_operations), 2559 DIR("fd", S_IRUSR|S_IXUSR, proc_fd_inode_operations, proc_fd_operations), 2560 DIR("fdinfo", S_IRUSR|S_IXUSR, proc_fdinfo_inode_operations, proc_fdinfo_operations), 2561 #ifdef CONFIG_NET 2562 DIR("net", S_IRUGO|S_IXUGO, proc_net_inode_operations, proc_net_operations), 2563 #endif 2564 REG("environ", S_IRUSR, proc_environ_operations), 2565 INF("auxv", S_IRUSR, proc_pid_auxv), 2566 ONE("status", S_IRUGO, proc_pid_status), 2567 ONE("personality", S_IRUSR, proc_pid_personality), 2568 INF("limits", S_IRUSR, proc_pid_limits), 2569 #ifdef CONFIG_SCHED_DEBUG 2570 REG("sched", S_IRUGO|S_IWUSR, proc_pid_sched_operations), 2571 #endif 2572 REG("comm", S_IRUGO|S_IWUSR, proc_pid_set_comm_operations), 2573 #ifdef CONFIG_HAVE_ARCH_TRACEHOOK 2574 INF("syscall", S_IRUSR, proc_pid_syscall), 2575 #endif 2576 INF("cmdline", S_IRUGO, proc_pid_cmdline), 2577 ONE("stat", S_IRUGO, proc_tgid_stat), 2578 ONE("statm", S_IRUGO, proc_pid_statm), 2579 REG("maps", S_IRUGO, proc_maps_operations), 2580 #ifdef CONFIG_NUMA 2581 REG("numa_maps", S_IRUGO, proc_numa_maps_operations), 2582 #endif 2583 REG("mem", S_IRUSR|S_IWUSR, proc_mem_operations), 2584 LNK("cwd", proc_cwd_link), 2585 LNK("root", proc_root_link), 2586 LNK("exe", proc_exe_link), 2587 REG("mounts", S_IRUGO, proc_mounts_operations), 2588 REG("mountinfo", S_IRUGO, proc_mountinfo_operations), 2589 REG("mountstats", S_IRUSR, proc_mountstats_operations), 2590 #ifdef CONFIG_PROC_PAGE_MONITOR 2591 REG("clear_refs", S_IWUSR, proc_clear_refs_operations), 2592 REG("smaps", S_IRUGO, proc_smaps_operations), 2593 REG("pagemap", S_IRUSR, proc_pagemap_operations), 2594 #endif 2595 #ifdef CONFIG_SECURITY 2596 DIR("attr", S_IRUGO|S_IXUGO, proc_attr_dir_inode_operations, proc_attr_dir_operations), 2597 #endif 2598 #ifdef CONFIG_KALLSYMS 2599 INF("wchan", S_IRUGO, proc_pid_wchan), 2600 #endif 2601 #ifdef CONFIG_STACKTRACE 2602 ONE("stack", S_IRUSR, proc_pid_stack), 2603 #endif 2604 #ifdef CONFIG_SCHEDSTATS 2605 INF("schedstat", S_IRUGO, proc_pid_schedstat), 2606 #endif 2607 #ifdef CONFIG_LATENCYTOP 2608 REG("latency", S_IRUGO, proc_lstats_operations), 2609 #endif 2610 #ifdef CONFIG_PROC_PID_CPUSET 2611 REG("cpuset", S_IRUGO, proc_cpuset_operations), 2612 #endif 2613 #ifdef CONFIG_CGROUPS 2614 REG("cgroup", S_IRUGO, proc_cgroup_operations), 2615 #endif 2616 INF("oom_score", S_IRUGO, proc_oom_score), 2617 REG("oom_adj", S_IRUGO|S_IWUSR, proc_oom_adjust_operations), 2618 #ifdef CONFIG_AUDITSYSCALL 2619 REG("loginuid", S_IWUSR|S_IRUGO, proc_loginuid_operations), 2620 REG("sessionid", S_IRUGO, proc_sessionid_operations), 2621 #endif 2622 #ifdef CONFIG_FAULT_INJECTION 2623 REG("make-it-fail", S_IRUGO|S_IWUSR, proc_fault_inject_operations), 2624 #endif 2625 #ifdef CONFIG_ELF_CORE 2626 REG("coredump_filter", S_IRUGO|S_IWUSR, proc_coredump_filter_operations), 2627 #endif 2628 #ifdef CONFIG_TASK_IO_ACCOUNTING 2629 INF("io", S_IRUGO, proc_tgid_io_accounting), 2630 #endif 2631 }; 2632 2633 static int proc_tgid_base_readdir(struct file * filp, 2634 void * dirent, filldir_t filldir) 2635 { 2636 return proc_pident_readdir(filp,dirent,filldir, 2637 tgid_base_stuff,ARRAY_SIZE(tgid_base_stuff)); 2638 } 2639 2640 static const struct file_operations proc_tgid_base_operations = { 2641 .read = generic_read_dir, 2642 .readdir = proc_tgid_base_readdir, 2643 }; 2644 2645 static struct dentry *proc_tgid_base_lookup(struct inode *dir, struct dentry *dentry, struct nameidata *nd){ 2646 return proc_pident_lookup(dir, dentry, 2647 tgid_base_stuff, ARRAY_SIZE(tgid_base_stuff)); 2648 } 2649 2650 static const struct inode_operations proc_tgid_base_inode_operations = { 2651 .lookup = proc_tgid_base_lookup, 2652 .getattr = pid_getattr, 2653 .setattr = proc_setattr, 2654 }; 2655 2656 static void proc_flush_task_mnt(struct vfsmount *mnt, pid_t pid, pid_t tgid) 2657 { 2658 struct dentry *dentry, *leader, *dir; 2659 char buf[PROC_NUMBUF]; 2660 struct qstr name; 2661 2662 name.name = buf; 2663 name.len = snprintf(buf, sizeof(buf), "%d", pid); 2664 dentry = d_hash_and_lookup(mnt->mnt_root, &name); 2665 if (dentry) { 2666 shrink_dcache_parent(dentry); 2667 d_drop(dentry); 2668 dput(dentry); 2669 } 2670 2671 name.name = buf; 2672 name.len = snprintf(buf, sizeof(buf), "%d", tgid); 2673 leader = d_hash_and_lookup(mnt->mnt_root, &name); 2674 if (!leader) 2675 goto out; 2676 2677 name.name = "task"; 2678 name.len = strlen(name.name); 2679 dir = d_hash_and_lookup(leader, &name); 2680 if (!dir) 2681 goto out_put_leader; 2682 2683 name.name = buf; 2684 name.len = snprintf(buf, sizeof(buf), "%d", pid); 2685 dentry = d_hash_and_lookup(dir, &name); 2686 if (dentry) { 2687 shrink_dcache_parent(dentry); 2688 d_drop(dentry); 2689 dput(dentry); 2690 } 2691 2692 dput(dir); 2693 out_put_leader: 2694 dput(leader); 2695 out: 2696 return; 2697 } 2698 2699 /** 2700 * proc_flush_task - Remove dcache entries for @task from the /proc dcache. 2701 * @task: task that should be flushed. 2702 * 2703 * When flushing dentries from proc, one needs to flush them from global 2704 * proc (proc_mnt) and from all the namespaces' procs this task was seen 2705 * in. This call is supposed to do all of this job. 2706 * 2707 * Looks in the dcache for 2708 * /proc/@pid 2709 * /proc/@tgid/task/@pid 2710 * if either directory is present flushes it and all of it'ts children 2711 * from the dcache. 2712 * 2713 * It is safe and reasonable to cache /proc entries for a task until 2714 * that task exits. After that they just clog up the dcache with 2715 * useless entries, possibly causing useful dcache entries to be 2716 * flushed instead. This routine is proved to flush those useless 2717 * dcache entries at process exit time. 2718 * 2719 * NOTE: This routine is just an optimization so it does not guarantee 2720 * that no dcache entries will exist at process exit time it 2721 * just makes it very unlikely that any will persist. 2722 */ 2723 2724 void proc_flush_task(struct task_struct *task) 2725 { 2726 int i; 2727 struct pid *pid, *tgid; 2728 struct upid *upid; 2729 2730 pid = task_pid(task); 2731 tgid = task_tgid(task); 2732 2733 for (i = 0; i <= pid->level; i++) { 2734 upid = &pid->numbers[i]; 2735 proc_flush_task_mnt(upid->ns->proc_mnt, upid->nr, 2736 tgid->numbers[i].nr); 2737 } 2738 2739 upid = &pid->numbers[pid->level]; 2740 if (upid->nr == 1) 2741 pid_ns_release_proc(upid->ns); 2742 } 2743 2744 static struct dentry *proc_pid_instantiate(struct inode *dir, 2745 struct dentry * dentry, 2746 struct task_struct *task, const void *ptr) 2747 { 2748 struct dentry *error = ERR_PTR(-ENOENT); 2749 struct inode *inode; 2750 2751 inode = proc_pid_make_inode(dir->i_sb, task); 2752 if (!inode) 2753 goto out; 2754 2755 inode->i_mode = S_IFDIR|S_IRUGO|S_IXUGO; 2756 inode->i_op = &proc_tgid_base_inode_operations; 2757 inode->i_fop = &proc_tgid_base_operations; 2758 inode->i_flags|=S_IMMUTABLE; 2759 2760 inode->i_nlink = 2 + pid_entry_count_dirs(tgid_base_stuff, 2761 ARRAY_SIZE(tgid_base_stuff)); 2762 2763 dentry->d_op = &pid_dentry_operations; 2764 2765 d_add(dentry, inode); 2766 /* Close the race of the process dying before we return the dentry */ 2767 if (pid_revalidate(dentry, NULL)) 2768 error = NULL; 2769 out: 2770 return error; 2771 } 2772 2773 struct dentry *proc_pid_lookup(struct inode *dir, struct dentry * dentry, struct nameidata *nd) 2774 { 2775 struct dentry *result = ERR_PTR(-ENOENT); 2776 struct task_struct *task; 2777 unsigned tgid; 2778 struct pid_namespace *ns; 2779 2780 result = proc_base_lookup(dir, dentry); 2781 if (!IS_ERR(result) || PTR_ERR(result) != -ENOENT) 2782 goto out; 2783 2784 tgid = name_to_int(dentry); 2785 if (tgid == ~0U) 2786 goto out; 2787 2788 ns = dentry->d_sb->s_fs_info; 2789 rcu_read_lock(); 2790 task = find_task_by_pid_ns(tgid, ns); 2791 if (task) 2792 get_task_struct(task); 2793 rcu_read_unlock(); 2794 if (!task) 2795 goto out; 2796 2797 result = proc_pid_instantiate(dir, dentry, task, NULL); 2798 put_task_struct(task); 2799 out: 2800 return result; 2801 } 2802 2803 /* 2804 * Find the first task with tgid >= tgid 2805 * 2806 */ 2807 struct tgid_iter { 2808 unsigned int tgid; 2809 struct task_struct *task; 2810 }; 2811 static struct tgid_iter next_tgid(struct pid_namespace *ns, struct tgid_iter iter) 2812 { 2813 struct pid *pid; 2814 2815 if (iter.task) 2816 put_task_struct(iter.task); 2817 rcu_read_lock(); 2818 retry: 2819 iter.task = NULL; 2820 pid = find_ge_pid(iter.tgid, ns); 2821 if (pid) { 2822 iter.tgid = pid_nr_ns(pid, ns); 2823 iter.task = pid_task(pid, PIDTYPE_PID); 2824 /* What we to know is if the pid we have find is the 2825 * pid of a thread_group_leader. Testing for task 2826 * being a thread_group_leader is the obvious thing 2827 * todo but there is a window when it fails, due to 2828 * the pid transfer logic in de_thread. 2829 * 2830 * So we perform the straight forward test of seeing 2831 * if the pid we have found is the pid of a thread 2832 * group leader, and don't worry if the task we have 2833 * found doesn't happen to be a thread group leader. 2834 * As we don't care in the case of readdir. 2835 */ 2836 if (!iter.task || !has_group_leader_pid(iter.task)) { 2837 iter.tgid += 1; 2838 goto retry; 2839 } 2840 get_task_struct(iter.task); 2841 } 2842 rcu_read_unlock(); 2843 return iter; 2844 } 2845 2846 #define TGID_OFFSET (FIRST_PROCESS_ENTRY + ARRAY_SIZE(proc_base_stuff)) 2847 2848 static int proc_pid_fill_cache(struct file *filp, void *dirent, filldir_t filldir, 2849 struct tgid_iter iter) 2850 { 2851 char name[PROC_NUMBUF]; 2852 int len = snprintf(name, sizeof(name), "%d", iter.tgid); 2853 return proc_fill_cache(filp, dirent, filldir, name, len, 2854 proc_pid_instantiate, iter.task, NULL); 2855 } 2856 2857 /* for the /proc/ directory itself, after non-process stuff has been done */ 2858 int proc_pid_readdir(struct file * filp, void * dirent, filldir_t filldir) 2859 { 2860 unsigned int nr = filp->f_pos - FIRST_PROCESS_ENTRY; 2861 struct task_struct *reaper = get_proc_task(filp->f_path.dentry->d_inode); 2862 struct tgid_iter iter; 2863 struct pid_namespace *ns; 2864 2865 if (!reaper) 2866 goto out_no_task; 2867 2868 for (; nr < ARRAY_SIZE(proc_base_stuff); filp->f_pos++, nr++) { 2869 const struct pid_entry *p = &proc_base_stuff[nr]; 2870 if (proc_base_fill_cache(filp, dirent, filldir, reaper, p) < 0) 2871 goto out; 2872 } 2873 2874 ns = filp->f_dentry->d_sb->s_fs_info; 2875 iter.task = NULL; 2876 iter.tgid = filp->f_pos - TGID_OFFSET; 2877 for (iter = next_tgid(ns, iter); 2878 iter.task; 2879 iter.tgid += 1, iter = next_tgid(ns, iter)) { 2880 filp->f_pos = iter.tgid + TGID_OFFSET; 2881 if (proc_pid_fill_cache(filp, dirent, filldir, iter) < 0) { 2882 put_task_struct(iter.task); 2883 goto out; 2884 } 2885 } 2886 filp->f_pos = PID_MAX_LIMIT + TGID_OFFSET; 2887 out: 2888 put_task_struct(reaper); 2889 out_no_task: 2890 return 0; 2891 } 2892 2893 /* 2894 * Tasks 2895 */ 2896 static const struct pid_entry tid_base_stuff[] = { 2897 DIR("fd", S_IRUSR|S_IXUSR, proc_fd_inode_operations, proc_fd_operations), 2898 DIR("fdinfo", S_IRUSR|S_IXUSR, proc_fdinfo_inode_operations, proc_fd_operations), 2899 REG("environ", S_IRUSR, proc_environ_operations), 2900 INF("auxv", S_IRUSR, proc_pid_auxv), 2901 ONE("status", S_IRUGO, proc_pid_status), 2902 ONE("personality", S_IRUSR, proc_pid_personality), 2903 INF("limits", S_IRUSR, proc_pid_limits), 2904 #ifdef CONFIG_SCHED_DEBUG 2905 REG("sched", S_IRUGO|S_IWUSR, proc_pid_sched_operations), 2906 #endif 2907 REG("comm", S_IRUGO|S_IWUSR, proc_pid_set_comm_operations), 2908 #ifdef CONFIG_HAVE_ARCH_TRACEHOOK 2909 INF("syscall", S_IRUSR, proc_pid_syscall), 2910 #endif 2911 INF("cmdline", S_IRUGO, proc_pid_cmdline), 2912 ONE("stat", S_IRUGO, proc_tid_stat), 2913 ONE("statm", S_IRUGO, proc_pid_statm), 2914 REG("maps", S_IRUGO, proc_maps_operations), 2915 #ifdef CONFIG_NUMA 2916 REG("numa_maps", S_IRUGO, proc_numa_maps_operations), 2917 #endif 2918 REG("mem", S_IRUSR|S_IWUSR, proc_mem_operations), 2919 LNK("cwd", proc_cwd_link), 2920 LNK("root", proc_root_link), 2921 LNK("exe", proc_exe_link), 2922 REG("mounts", S_IRUGO, proc_mounts_operations), 2923 REG("mountinfo", S_IRUGO, proc_mountinfo_operations), 2924 #ifdef CONFIG_PROC_PAGE_MONITOR 2925 REG("clear_refs", S_IWUSR, proc_clear_refs_operations), 2926 REG("smaps", S_IRUGO, proc_smaps_operations), 2927 REG("pagemap", S_IRUSR, proc_pagemap_operations), 2928 #endif 2929 #ifdef CONFIG_SECURITY 2930 DIR("attr", S_IRUGO|S_IXUGO, proc_attr_dir_inode_operations, proc_attr_dir_operations), 2931 #endif 2932 #ifdef CONFIG_KALLSYMS 2933 INF("wchan", S_IRUGO, proc_pid_wchan), 2934 #endif 2935 #ifdef CONFIG_STACKTRACE 2936 ONE("stack", S_IRUSR, proc_pid_stack), 2937 #endif 2938 #ifdef CONFIG_SCHEDSTATS 2939 INF("schedstat", S_IRUGO, proc_pid_schedstat), 2940 #endif 2941 #ifdef CONFIG_LATENCYTOP 2942 REG("latency", S_IRUGO, proc_lstats_operations), 2943 #endif 2944 #ifdef CONFIG_PROC_PID_CPUSET 2945 REG("cpuset", S_IRUGO, proc_cpuset_operations), 2946 #endif 2947 #ifdef CONFIG_CGROUPS 2948 REG("cgroup", S_IRUGO, proc_cgroup_operations), 2949 #endif 2950 INF("oom_score", S_IRUGO, proc_oom_score), 2951 REG("oom_adj", S_IRUGO|S_IWUSR, proc_oom_adjust_operations), 2952 #ifdef CONFIG_AUDITSYSCALL 2953 REG("loginuid", S_IWUSR|S_IRUGO, proc_loginuid_operations), 2954 REG("sessionid", S_IRUSR, proc_sessionid_operations), 2955 #endif 2956 #ifdef CONFIG_FAULT_INJECTION 2957 REG("make-it-fail", S_IRUGO|S_IWUSR, proc_fault_inject_operations), 2958 #endif 2959 #ifdef CONFIG_TASK_IO_ACCOUNTING 2960 INF("io", S_IRUGO, proc_tid_io_accounting), 2961 #endif 2962 }; 2963 2964 static int proc_tid_base_readdir(struct file * filp, 2965 void * dirent, filldir_t filldir) 2966 { 2967 return proc_pident_readdir(filp,dirent,filldir, 2968 tid_base_stuff,ARRAY_SIZE(tid_base_stuff)); 2969 } 2970 2971 static struct dentry *proc_tid_base_lookup(struct inode *dir, struct dentry *dentry, struct nameidata *nd){ 2972 return proc_pident_lookup(dir, dentry, 2973 tid_base_stuff, ARRAY_SIZE(tid_base_stuff)); 2974 } 2975 2976 static const struct file_operations proc_tid_base_operations = { 2977 .read = generic_read_dir, 2978 .readdir = proc_tid_base_readdir, 2979 }; 2980 2981 static const struct inode_operations proc_tid_base_inode_operations = { 2982 .lookup = proc_tid_base_lookup, 2983 .getattr = pid_getattr, 2984 .setattr = proc_setattr, 2985 }; 2986 2987 static struct dentry *proc_task_instantiate(struct inode *dir, 2988 struct dentry *dentry, struct task_struct *task, const void *ptr) 2989 { 2990 struct dentry *error = ERR_PTR(-ENOENT); 2991 struct inode *inode; 2992 inode = proc_pid_make_inode(dir->i_sb, task); 2993 2994 if (!inode) 2995 goto out; 2996 inode->i_mode = S_IFDIR|S_IRUGO|S_IXUGO; 2997 inode->i_op = &proc_tid_base_inode_operations; 2998 inode->i_fop = &proc_tid_base_operations; 2999 inode->i_flags|=S_IMMUTABLE; 3000 3001 inode->i_nlink = 2 + pid_entry_count_dirs(tid_base_stuff, 3002 ARRAY_SIZE(tid_base_stuff)); 3003 3004 dentry->d_op = &pid_dentry_operations; 3005 3006 d_add(dentry, inode); 3007 /* Close the race of the process dying before we return the dentry */ 3008 if (pid_revalidate(dentry, NULL)) 3009 error = NULL; 3010 out: 3011 return error; 3012 } 3013 3014 static struct dentry *proc_task_lookup(struct inode *dir, struct dentry * dentry, struct nameidata *nd) 3015 { 3016 struct dentry *result = ERR_PTR(-ENOENT); 3017 struct task_struct *task; 3018 struct task_struct *leader = get_proc_task(dir); 3019 unsigned tid; 3020 struct pid_namespace *ns; 3021 3022 if (!leader) 3023 goto out_no_task; 3024 3025 tid = name_to_int(dentry); 3026 if (tid == ~0U) 3027 goto out; 3028 3029 ns = dentry->d_sb->s_fs_info; 3030 rcu_read_lock(); 3031 task = find_task_by_pid_ns(tid, ns); 3032 if (task) 3033 get_task_struct(task); 3034 rcu_read_unlock(); 3035 if (!task) 3036 goto out; 3037 if (!same_thread_group(leader, task)) 3038 goto out_drop_task; 3039 3040 result = proc_task_instantiate(dir, dentry, task, NULL); 3041 out_drop_task: 3042 put_task_struct(task); 3043 out: 3044 put_task_struct(leader); 3045 out_no_task: 3046 return result; 3047 } 3048 3049 /* 3050 * Find the first tid of a thread group to return to user space. 3051 * 3052 * Usually this is just the thread group leader, but if the users 3053 * buffer was too small or there was a seek into the middle of the 3054 * directory we have more work todo. 3055 * 3056 * In the case of a short read we start with find_task_by_pid. 3057 * 3058 * In the case of a seek we start with the leader and walk nr 3059 * threads past it. 3060 */ 3061 static struct task_struct *first_tid(struct task_struct *leader, 3062 int tid, int nr, struct pid_namespace *ns) 3063 { 3064 struct task_struct *pos; 3065 3066 rcu_read_lock(); 3067 /* Attempt to start with the pid of a thread */ 3068 if (tid && (nr > 0)) { 3069 pos = find_task_by_pid_ns(tid, ns); 3070 if (pos && (pos->group_leader == leader)) 3071 goto found; 3072 } 3073 3074 /* If nr exceeds the number of threads there is nothing todo */ 3075 pos = NULL; 3076 if (nr && nr >= get_nr_threads(leader)) 3077 goto out; 3078 3079 /* If we haven't found our starting place yet start 3080 * with the leader and walk nr threads forward. 3081 */ 3082 for (pos = leader; nr > 0; --nr) { 3083 pos = next_thread(pos); 3084 if (pos == leader) { 3085 pos = NULL; 3086 goto out; 3087 } 3088 } 3089 found: 3090 get_task_struct(pos); 3091 out: 3092 rcu_read_unlock(); 3093 return pos; 3094 } 3095 3096 /* 3097 * Find the next thread in the thread list. 3098 * Return NULL if there is an error or no next thread. 3099 * 3100 * The reference to the input task_struct is released. 3101 */ 3102 static struct task_struct *next_tid(struct task_struct *start) 3103 { 3104 struct task_struct *pos = NULL; 3105 rcu_read_lock(); 3106 if (pid_alive(start)) { 3107 pos = next_thread(start); 3108 if (thread_group_leader(pos)) 3109 pos = NULL; 3110 else 3111 get_task_struct(pos); 3112 } 3113 rcu_read_unlock(); 3114 put_task_struct(start); 3115 return pos; 3116 } 3117 3118 static int proc_task_fill_cache(struct file *filp, void *dirent, filldir_t filldir, 3119 struct task_struct *task, int tid) 3120 { 3121 char name[PROC_NUMBUF]; 3122 int len = snprintf(name, sizeof(name), "%d", tid); 3123 return proc_fill_cache(filp, dirent, filldir, name, len, 3124 proc_task_instantiate, task, NULL); 3125 } 3126 3127 /* for the /proc/TGID/task/ directories */ 3128 static int proc_task_readdir(struct file * filp, void * dirent, filldir_t filldir) 3129 { 3130 struct dentry *dentry = filp->f_path.dentry; 3131 struct inode *inode = dentry->d_inode; 3132 struct task_struct *leader = NULL; 3133 struct task_struct *task; 3134 int retval = -ENOENT; 3135 ino_t ino; 3136 int tid; 3137 struct pid_namespace *ns; 3138 3139 task = get_proc_task(inode); 3140 if (!task) 3141 goto out_no_task; 3142 rcu_read_lock(); 3143 if (pid_alive(task)) { 3144 leader = task->group_leader; 3145 get_task_struct(leader); 3146 } 3147 rcu_read_unlock(); 3148 put_task_struct(task); 3149 if (!leader) 3150 goto out_no_task; 3151 retval = 0; 3152 3153 switch ((unsigned long)filp->f_pos) { 3154 case 0: 3155 ino = inode->i_ino; 3156 if (filldir(dirent, ".", 1, filp->f_pos, ino, DT_DIR) < 0) 3157 goto out; 3158 filp->f_pos++; 3159 /* fall through */ 3160 case 1: 3161 ino = parent_ino(dentry); 3162 if (filldir(dirent, "..", 2, filp->f_pos, ino, DT_DIR) < 0) 3163 goto out; 3164 filp->f_pos++; 3165 /* fall through */ 3166 } 3167 3168 /* f_version caches the tgid value that the last readdir call couldn't 3169 * return. lseek aka telldir automagically resets f_version to 0. 3170 */ 3171 ns = filp->f_dentry->d_sb->s_fs_info; 3172 tid = (int)filp->f_version; 3173 filp->f_version = 0; 3174 for (task = first_tid(leader, tid, filp->f_pos - 2, ns); 3175 task; 3176 task = next_tid(task), filp->f_pos++) { 3177 tid = task_pid_nr_ns(task, ns); 3178 if (proc_task_fill_cache(filp, dirent, filldir, task, tid) < 0) { 3179 /* returning this tgid failed, save it as the first 3180 * pid for the next readir call */ 3181 filp->f_version = (u64)tid; 3182 put_task_struct(task); 3183 break; 3184 } 3185 } 3186 out: 3187 put_task_struct(leader); 3188 out_no_task: 3189 return retval; 3190 } 3191 3192 static int proc_task_getattr(struct vfsmount *mnt, struct dentry *dentry, struct kstat *stat) 3193 { 3194 struct inode *inode = dentry->d_inode; 3195 struct task_struct *p = get_proc_task(inode); 3196 generic_fillattr(inode, stat); 3197 3198 if (p) { 3199 stat->nlink += get_nr_threads(p); 3200 put_task_struct(p); 3201 } 3202 3203 return 0; 3204 } 3205 3206 static const struct inode_operations proc_task_inode_operations = { 3207 .lookup = proc_task_lookup, 3208 .getattr = proc_task_getattr, 3209 .setattr = proc_setattr, 3210 }; 3211 3212 static const struct file_operations proc_task_operations = { 3213 .read = generic_read_dir, 3214 .readdir = proc_task_readdir, 3215 }; 3216