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/config.h> 53 #include <linux/errno.h> 54 #include <linux/time.h> 55 #include <linux/proc_fs.h> 56 #include <linux/stat.h> 57 #include <linux/init.h> 58 #include <linux/capability.h> 59 #include <linux/file.h> 60 #include <linux/string.h> 61 #include <linux/seq_file.h> 62 #include <linux/namei.h> 63 #include <linux/namespace.h> 64 #include <linux/mm.h> 65 #include <linux/smp_lock.h> 66 #include <linux/rcupdate.h> 67 #include <linux/kallsyms.h> 68 #include <linux/mount.h> 69 #include <linux/security.h> 70 #include <linux/ptrace.h> 71 #include <linux/seccomp.h> 72 #include <linux/cpuset.h> 73 #include <linux/audit.h> 74 #include <linux/poll.h> 75 #include "internal.h" 76 77 /* 78 * For hysterical raisins we keep the same inumbers as in the old procfs. 79 * Feel free to change the macro below - just keep the range distinct from 80 * inumbers of the rest of procfs (currently those are in 0x0000--0xffff). 81 * As soon as we'll get a separate superblock we will be able to forget 82 * about magical ranges too. 83 */ 84 85 #define fake_ino(pid,ino) (((pid)<<16)|(ino)) 86 87 enum pid_directory_inos { 88 PROC_TGID_INO = 2, 89 PROC_TGID_TASK, 90 PROC_TGID_STATUS, 91 PROC_TGID_MEM, 92 #ifdef CONFIG_SECCOMP 93 PROC_TGID_SECCOMP, 94 #endif 95 PROC_TGID_CWD, 96 PROC_TGID_ROOT, 97 PROC_TGID_EXE, 98 PROC_TGID_FD, 99 PROC_TGID_ENVIRON, 100 PROC_TGID_AUXV, 101 PROC_TGID_CMDLINE, 102 PROC_TGID_STAT, 103 PROC_TGID_STATM, 104 PROC_TGID_MAPS, 105 PROC_TGID_NUMA_MAPS, 106 PROC_TGID_MOUNTS, 107 PROC_TGID_WCHAN, 108 #ifdef CONFIG_MMU 109 PROC_TGID_SMAPS, 110 #endif 111 #ifdef CONFIG_SCHEDSTATS 112 PROC_TGID_SCHEDSTAT, 113 #endif 114 #ifdef CONFIG_CPUSETS 115 PROC_TGID_CPUSET, 116 #endif 117 #ifdef CONFIG_SECURITY 118 PROC_TGID_ATTR, 119 PROC_TGID_ATTR_CURRENT, 120 PROC_TGID_ATTR_PREV, 121 PROC_TGID_ATTR_EXEC, 122 PROC_TGID_ATTR_FSCREATE, 123 #endif 124 #ifdef CONFIG_AUDITSYSCALL 125 PROC_TGID_LOGINUID, 126 #endif 127 PROC_TGID_OOM_SCORE, 128 PROC_TGID_OOM_ADJUST, 129 PROC_TID_INO, 130 PROC_TID_STATUS, 131 PROC_TID_MEM, 132 #ifdef CONFIG_SECCOMP 133 PROC_TID_SECCOMP, 134 #endif 135 PROC_TID_CWD, 136 PROC_TID_ROOT, 137 PROC_TID_EXE, 138 PROC_TID_FD, 139 PROC_TID_ENVIRON, 140 PROC_TID_AUXV, 141 PROC_TID_CMDLINE, 142 PROC_TID_STAT, 143 PROC_TID_STATM, 144 PROC_TID_MAPS, 145 PROC_TID_NUMA_MAPS, 146 PROC_TID_MOUNTS, 147 PROC_TID_WCHAN, 148 #ifdef CONFIG_MMU 149 PROC_TID_SMAPS, 150 #endif 151 #ifdef CONFIG_SCHEDSTATS 152 PROC_TID_SCHEDSTAT, 153 #endif 154 #ifdef CONFIG_CPUSETS 155 PROC_TID_CPUSET, 156 #endif 157 #ifdef CONFIG_SECURITY 158 PROC_TID_ATTR, 159 PROC_TID_ATTR_CURRENT, 160 PROC_TID_ATTR_PREV, 161 PROC_TID_ATTR_EXEC, 162 PROC_TID_ATTR_FSCREATE, 163 #endif 164 #ifdef CONFIG_AUDITSYSCALL 165 PROC_TID_LOGINUID, 166 #endif 167 PROC_TID_OOM_SCORE, 168 PROC_TID_OOM_ADJUST, 169 170 /* Add new entries before this */ 171 PROC_TID_FD_DIR = 0x8000, /* 0x8000-0xffff */ 172 }; 173 174 struct pid_entry { 175 int type; 176 int len; 177 char *name; 178 mode_t mode; 179 }; 180 181 #define E(type,name,mode) {(type),sizeof(name)-1,(name),(mode)} 182 183 static struct pid_entry tgid_base_stuff[] = { 184 E(PROC_TGID_TASK, "task", S_IFDIR|S_IRUGO|S_IXUGO), 185 E(PROC_TGID_FD, "fd", S_IFDIR|S_IRUSR|S_IXUSR), 186 E(PROC_TGID_ENVIRON, "environ", S_IFREG|S_IRUSR), 187 E(PROC_TGID_AUXV, "auxv", S_IFREG|S_IRUSR), 188 E(PROC_TGID_STATUS, "status", S_IFREG|S_IRUGO), 189 E(PROC_TGID_CMDLINE, "cmdline", S_IFREG|S_IRUGO), 190 E(PROC_TGID_STAT, "stat", S_IFREG|S_IRUGO), 191 E(PROC_TGID_STATM, "statm", S_IFREG|S_IRUGO), 192 E(PROC_TGID_MAPS, "maps", S_IFREG|S_IRUGO), 193 #ifdef CONFIG_NUMA 194 E(PROC_TGID_NUMA_MAPS, "numa_maps", S_IFREG|S_IRUGO), 195 #endif 196 E(PROC_TGID_MEM, "mem", S_IFREG|S_IRUSR|S_IWUSR), 197 #ifdef CONFIG_SECCOMP 198 E(PROC_TGID_SECCOMP, "seccomp", S_IFREG|S_IRUSR|S_IWUSR), 199 #endif 200 E(PROC_TGID_CWD, "cwd", S_IFLNK|S_IRWXUGO), 201 E(PROC_TGID_ROOT, "root", S_IFLNK|S_IRWXUGO), 202 E(PROC_TGID_EXE, "exe", S_IFLNK|S_IRWXUGO), 203 E(PROC_TGID_MOUNTS, "mounts", S_IFREG|S_IRUGO), 204 #ifdef CONFIG_MMU 205 E(PROC_TGID_SMAPS, "smaps", S_IFREG|S_IRUGO), 206 #endif 207 #ifdef CONFIG_SECURITY 208 E(PROC_TGID_ATTR, "attr", S_IFDIR|S_IRUGO|S_IXUGO), 209 #endif 210 #ifdef CONFIG_KALLSYMS 211 E(PROC_TGID_WCHAN, "wchan", S_IFREG|S_IRUGO), 212 #endif 213 #ifdef CONFIG_SCHEDSTATS 214 E(PROC_TGID_SCHEDSTAT, "schedstat", S_IFREG|S_IRUGO), 215 #endif 216 #ifdef CONFIG_CPUSETS 217 E(PROC_TGID_CPUSET, "cpuset", S_IFREG|S_IRUGO), 218 #endif 219 E(PROC_TGID_OOM_SCORE, "oom_score",S_IFREG|S_IRUGO), 220 E(PROC_TGID_OOM_ADJUST,"oom_adj", S_IFREG|S_IRUGO|S_IWUSR), 221 #ifdef CONFIG_AUDITSYSCALL 222 E(PROC_TGID_LOGINUID, "loginuid", S_IFREG|S_IWUSR|S_IRUGO), 223 #endif 224 {0,0,NULL,0} 225 }; 226 static struct pid_entry tid_base_stuff[] = { 227 E(PROC_TID_FD, "fd", S_IFDIR|S_IRUSR|S_IXUSR), 228 E(PROC_TID_ENVIRON, "environ", S_IFREG|S_IRUSR), 229 E(PROC_TID_AUXV, "auxv", S_IFREG|S_IRUSR), 230 E(PROC_TID_STATUS, "status", S_IFREG|S_IRUGO), 231 E(PROC_TID_CMDLINE, "cmdline", S_IFREG|S_IRUGO), 232 E(PROC_TID_STAT, "stat", S_IFREG|S_IRUGO), 233 E(PROC_TID_STATM, "statm", S_IFREG|S_IRUGO), 234 E(PROC_TID_MAPS, "maps", S_IFREG|S_IRUGO), 235 #ifdef CONFIG_NUMA 236 E(PROC_TID_NUMA_MAPS, "numa_maps", S_IFREG|S_IRUGO), 237 #endif 238 E(PROC_TID_MEM, "mem", S_IFREG|S_IRUSR|S_IWUSR), 239 #ifdef CONFIG_SECCOMP 240 E(PROC_TID_SECCOMP, "seccomp", S_IFREG|S_IRUSR|S_IWUSR), 241 #endif 242 E(PROC_TID_CWD, "cwd", S_IFLNK|S_IRWXUGO), 243 E(PROC_TID_ROOT, "root", S_IFLNK|S_IRWXUGO), 244 E(PROC_TID_EXE, "exe", S_IFLNK|S_IRWXUGO), 245 E(PROC_TID_MOUNTS, "mounts", S_IFREG|S_IRUGO), 246 #ifdef CONFIG_MMU 247 E(PROC_TID_SMAPS, "smaps", S_IFREG|S_IRUGO), 248 #endif 249 #ifdef CONFIG_SECURITY 250 E(PROC_TID_ATTR, "attr", S_IFDIR|S_IRUGO|S_IXUGO), 251 #endif 252 #ifdef CONFIG_KALLSYMS 253 E(PROC_TID_WCHAN, "wchan", S_IFREG|S_IRUGO), 254 #endif 255 #ifdef CONFIG_SCHEDSTATS 256 E(PROC_TID_SCHEDSTAT, "schedstat",S_IFREG|S_IRUGO), 257 #endif 258 #ifdef CONFIG_CPUSETS 259 E(PROC_TID_CPUSET, "cpuset", S_IFREG|S_IRUGO), 260 #endif 261 E(PROC_TID_OOM_SCORE, "oom_score",S_IFREG|S_IRUGO), 262 E(PROC_TID_OOM_ADJUST, "oom_adj", S_IFREG|S_IRUGO|S_IWUSR), 263 #ifdef CONFIG_AUDITSYSCALL 264 E(PROC_TID_LOGINUID, "loginuid", S_IFREG|S_IWUSR|S_IRUGO), 265 #endif 266 {0,0,NULL,0} 267 }; 268 269 #ifdef CONFIG_SECURITY 270 static struct pid_entry tgid_attr_stuff[] = { 271 E(PROC_TGID_ATTR_CURRENT, "current", S_IFREG|S_IRUGO|S_IWUGO), 272 E(PROC_TGID_ATTR_PREV, "prev", S_IFREG|S_IRUGO), 273 E(PROC_TGID_ATTR_EXEC, "exec", S_IFREG|S_IRUGO|S_IWUGO), 274 E(PROC_TGID_ATTR_FSCREATE, "fscreate", S_IFREG|S_IRUGO|S_IWUGO), 275 {0,0,NULL,0} 276 }; 277 static struct pid_entry tid_attr_stuff[] = { 278 E(PROC_TID_ATTR_CURRENT, "current", S_IFREG|S_IRUGO|S_IWUGO), 279 E(PROC_TID_ATTR_PREV, "prev", S_IFREG|S_IRUGO), 280 E(PROC_TID_ATTR_EXEC, "exec", S_IFREG|S_IRUGO|S_IWUGO), 281 E(PROC_TID_ATTR_FSCREATE, "fscreate", S_IFREG|S_IRUGO|S_IWUGO), 282 {0,0,NULL,0} 283 }; 284 #endif 285 286 #undef E 287 288 static int proc_fd_link(struct inode *inode, struct dentry **dentry, struct vfsmount **mnt) 289 { 290 struct task_struct *task = proc_task(inode); 291 struct files_struct *files; 292 struct file *file; 293 int fd = proc_type(inode) - PROC_TID_FD_DIR; 294 295 files = get_files_struct(task); 296 if (files) { 297 rcu_read_lock(); 298 file = fcheck_files(files, fd); 299 if (file) { 300 *mnt = mntget(file->f_vfsmnt); 301 *dentry = dget(file->f_dentry); 302 rcu_read_unlock(); 303 put_files_struct(files); 304 return 0; 305 } 306 rcu_read_unlock(); 307 put_files_struct(files); 308 } 309 return -ENOENT; 310 } 311 312 static struct fs_struct *get_fs_struct(struct task_struct *task) 313 { 314 struct fs_struct *fs; 315 task_lock(task); 316 fs = task->fs; 317 if(fs) 318 atomic_inc(&fs->count); 319 task_unlock(task); 320 return fs; 321 } 322 323 static int proc_cwd_link(struct inode *inode, struct dentry **dentry, struct vfsmount **mnt) 324 { 325 struct fs_struct *fs = get_fs_struct(proc_task(inode)); 326 int result = -ENOENT; 327 if (fs) { 328 read_lock(&fs->lock); 329 *mnt = mntget(fs->pwdmnt); 330 *dentry = dget(fs->pwd); 331 read_unlock(&fs->lock); 332 result = 0; 333 put_fs_struct(fs); 334 } 335 return result; 336 } 337 338 static int proc_root_link(struct inode *inode, struct dentry **dentry, struct vfsmount **mnt) 339 { 340 struct fs_struct *fs = get_fs_struct(proc_task(inode)); 341 int result = -ENOENT; 342 if (fs) { 343 read_lock(&fs->lock); 344 *mnt = mntget(fs->rootmnt); 345 *dentry = dget(fs->root); 346 read_unlock(&fs->lock); 347 result = 0; 348 put_fs_struct(fs); 349 } 350 return result; 351 } 352 353 354 /* Same as proc_root_link, but this addionally tries to get fs from other 355 * threads in the group */ 356 static int proc_task_root_link(struct inode *inode, struct dentry **dentry, 357 struct vfsmount **mnt) 358 { 359 struct fs_struct *fs; 360 int result = -ENOENT; 361 struct task_struct *leader = proc_task(inode); 362 363 task_lock(leader); 364 fs = leader->fs; 365 if (fs) { 366 atomic_inc(&fs->count); 367 task_unlock(leader); 368 } else { 369 /* Try to get fs from other threads */ 370 task_unlock(leader); 371 read_lock(&tasklist_lock); 372 if (pid_alive(leader)) { 373 struct task_struct *task = leader; 374 375 while ((task = next_thread(task)) != leader) { 376 task_lock(task); 377 fs = task->fs; 378 if (fs) { 379 atomic_inc(&fs->count); 380 task_unlock(task); 381 break; 382 } 383 task_unlock(task); 384 } 385 } 386 read_unlock(&tasklist_lock); 387 } 388 389 if (fs) { 390 read_lock(&fs->lock); 391 *mnt = mntget(fs->rootmnt); 392 *dentry = dget(fs->root); 393 read_unlock(&fs->lock); 394 result = 0; 395 put_fs_struct(fs); 396 } 397 return result; 398 } 399 400 401 #define MAY_PTRACE(task) \ 402 (task == current || \ 403 (task->parent == current && \ 404 (task->ptrace & PT_PTRACED) && \ 405 (task->state == TASK_STOPPED || task->state == TASK_TRACED) && \ 406 security_ptrace(current,task) == 0)) 407 408 static int proc_pid_environ(struct task_struct *task, char * buffer) 409 { 410 int res = 0; 411 struct mm_struct *mm = get_task_mm(task); 412 if (mm) { 413 unsigned int len = mm->env_end - mm->env_start; 414 if (len > PAGE_SIZE) 415 len = PAGE_SIZE; 416 res = access_process_vm(task, mm->env_start, buffer, len, 0); 417 if (!ptrace_may_attach(task)) 418 res = -ESRCH; 419 mmput(mm); 420 } 421 return res; 422 } 423 424 static int proc_pid_cmdline(struct task_struct *task, char * buffer) 425 { 426 int res = 0; 427 unsigned int len; 428 struct mm_struct *mm = get_task_mm(task); 429 if (!mm) 430 goto out; 431 if (!mm->arg_end) 432 goto out_mm; /* Shh! No looking before we're done */ 433 434 len = mm->arg_end - mm->arg_start; 435 436 if (len > PAGE_SIZE) 437 len = PAGE_SIZE; 438 439 res = access_process_vm(task, mm->arg_start, buffer, len, 0); 440 441 // If the nul at the end of args has been overwritten, then 442 // assume application is using setproctitle(3). 443 if (res > 0 && buffer[res-1] != '\0' && len < PAGE_SIZE) { 444 len = strnlen(buffer, res); 445 if (len < res) { 446 res = len; 447 } else { 448 len = mm->env_end - mm->env_start; 449 if (len > PAGE_SIZE - res) 450 len = PAGE_SIZE - res; 451 res += access_process_vm(task, mm->env_start, buffer+res, len, 0); 452 res = strnlen(buffer, res); 453 } 454 } 455 out_mm: 456 mmput(mm); 457 out: 458 return res; 459 } 460 461 static int proc_pid_auxv(struct task_struct *task, char *buffer) 462 { 463 int res = 0; 464 struct mm_struct *mm = get_task_mm(task); 465 if (mm) { 466 unsigned int nwords = 0; 467 do 468 nwords += 2; 469 while (mm->saved_auxv[nwords - 2] != 0); /* AT_NULL */ 470 res = nwords * sizeof(mm->saved_auxv[0]); 471 if (res > PAGE_SIZE) 472 res = PAGE_SIZE; 473 memcpy(buffer, mm->saved_auxv, res); 474 mmput(mm); 475 } 476 return res; 477 } 478 479 480 #ifdef CONFIG_KALLSYMS 481 /* 482 * Provides a wchan file via kallsyms in a proper one-value-per-file format. 483 * Returns the resolved symbol. If that fails, simply return the address. 484 */ 485 static int proc_pid_wchan(struct task_struct *task, char *buffer) 486 { 487 char *modname; 488 const char *sym_name; 489 unsigned long wchan, size, offset; 490 char namebuf[KSYM_NAME_LEN+1]; 491 492 wchan = get_wchan(task); 493 494 sym_name = kallsyms_lookup(wchan, &size, &offset, &modname, namebuf); 495 if (sym_name) 496 return sprintf(buffer, "%s", sym_name); 497 return sprintf(buffer, "%lu", wchan); 498 } 499 #endif /* CONFIG_KALLSYMS */ 500 501 #ifdef CONFIG_SCHEDSTATS 502 /* 503 * Provides /proc/PID/schedstat 504 */ 505 static int proc_pid_schedstat(struct task_struct *task, char *buffer) 506 { 507 return sprintf(buffer, "%lu %lu %lu\n", 508 task->sched_info.cpu_time, 509 task->sched_info.run_delay, 510 task->sched_info.pcnt); 511 } 512 #endif 513 514 /* The badness from the OOM killer */ 515 unsigned long badness(struct task_struct *p, unsigned long uptime); 516 static int proc_oom_score(struct task_struct *task, char *buffer) 517 { 518 unsigned long points; 519 struct timespec uptime; 520 521 do_posix_clock_monotonic_gettime(&uptime); 522 points = badness(task, uptime.tv_sec); 523 return sprintf(buffer, "%lu\n", points); 524 } 525 526 /************************************************************************/ 527 /* Here the fs part begins */ 528 /************************************************************************/ 529 530 /* permission checks */ 531 532 /* If the process being read is separated by chroot from the reading process, 533 * don't let the reader access the threads. 534 */ 535 static int proc_check_chroot(struct dentry *root, struct vfsmount *vfsmnt) 536 { 537 struct dentry *de, *base; 538 struct vfsmount *our_vfsmnt, *mnt; 539 int res = 0; 540 read_lock(¤t->fs->lock); 541 our_vfsmnt = mntget(current->fs->rootmnt); 542 base = dget(current->fs->root); 543 read_unlock(¤t->fs->lock); 544 545 spin_lock(&vfsmount_lock); 546 de = root; 547 mnt = vfsmnt; 548 549 while (vfsmnt != our_vfsmnt) { 550 if (vfsmnt == vfsmnt->mnt_parent) 551 goto out; 552 de = vfsmnt->mnt_mountpoint; 553 vfsmnt = vfsmnt->mnt_parent; 554 } 555 556 if (!is_subdir(de, base)) 557 goto out; 558 spin_unlock(&vfsmount_lock); 559 560 exit: 561 dput(base); 562 mntput(our_vfsmnt); 563 dput(root); 564 mntput(mnt); 565 return res; 566 out: 567 spin_unlock(&vfsmount_lock); 568 res = -EACCES; 569 goto exit; 570 } 571 572 static int proc_check_root(struct inode *inode) 573 { 574 struct dentry *root; 575 struct vfsmount *vfsmnt; 576 577 if (proc_root_link(inode, &root, &vfsmnt)) /* Ewww... */ 578 return -ENOENT; 579 return proc_check_chroot(root, vfsmnt); 580 } 581 582 static int proc_permission(struct inode *inode, int mask, struct nameidata *nd) 583 { 584 if (generic_permission(inode, mask, NULL) != 0) 585 return -EACCES; 586 return proc_check_root(inode); 587 } 588 589 static int proc_task_permission(struct inode *inode, int mask, struct nameidata *nd) 590 { 591 struct dentry *root; 592 struct vfsmount *vfsmnt; 593 594 if (generic_permission(inode, mask, NULL) != 0) 595 return -EACCES; 596 597 if (proc_task_root_link(inode, &root, &vfsmnt)) 598 return -ENOENT; 599 600 return proc_check_chroot(root, vfsmnt); 601 } 602 603 extern struct seq_operations proc_pid_maps_op; 604 static int maps_open(struct inode *inode, struct file *file) 605 { 606 struct task_struct *task = proc_task(inode); 607 int ret = seq_open(file, &proc_pid_maps_op); 608 if (!ret) { 609 struct seq_file *m = file->private_data; 610 m->private = task; 611 } 612 return ret; 613 } 614 615 static struct file_operations proc_maps_operations = { 616 .open = maps_open, 617 .read = seq_read, 618 .llseek = seq_lseek, 619 .release = seq_release, 620 }; 621 622 #ifdef CONFIG_NUMA 623 extern struct seq_operations proc_pid_numa_maps_op; 624 static int numa_maps_open(struct inode *inode, struct file *file) 625 { 626 struct task_struct *task = proc_task(inode); 627 int ret = seq_open(file, &proc_pid_numa_maps_op); 628 if (!ret) { 629 struct seq_file *m = file->private_data; 630 m->private = task; 631 } 632 return ret; 633 } 634 635 static struct file_operations proc_numa_maps_operations = { 636 .open = numa_maps_open, 637 .read = seq_read, 638 .llseek = seq_lseek, 639 .release = seq_release, 640 }; 641 #endif 642 643 #ifdef CONFIG_MMU 644 extern struct seq_operations proc_pid_smaps_op; 645 static int smaps_open(struct inode *inode, struct file *file) 646 { 647 struct task_struct *task = proc_task(inode); 648 int ret = seq_open(file, &proc_pid_smaps_op); 649 if (!ret) { 650 struct seq_file *m = file->private_data; 651 m->private = task; 652 } 653 return ret; 654 } 655 656 static struct file_operations proc_smaps_operations = { 657 .open = smaps_open, 658 .read = seq_read, 659 .llseek = seq_lseek, 660 .release = seq_release, 661 }; 662 #endif 663 664 extern struct seq_operations mounts_op; 665 struct proc_mounts { 666 struct seq_file m; 667 int event; 668 }; 669 670 static int mounts_open(struct inode *inode, struct file *file) 671 { 672 struct task_struct *task = proc_task(inode); 673 struct namespace *namespace; 674 struct proc_mounts *p; 675 int ret = -EINVAL; 676 677 task_lock(task); 678 namespace = task->namespace; 679 if (namespace) 680 get_namespace(namespace); 681 task_unlock(task); 682 683 if (namespace) { 684 ret = -ENOMEM; 685 p = kmalloc(sizeof(struct proc_mounts), GFP_KERNEL); 686 if (p) { 687 file->private_data = &p->m; 688 ret = seq_open(file, &mounts_op); 689 if (!ret) { 690 p->m.private = namespace; 691 p->event = namespace->event; 692 return 0; 693 } 694 kfree(p); 695 } 696 put_namespace(namespace); 697 } 698 return ret; 699 } 700 701 static int mounts_release(struct inode *inode, struct file *file) 702 { 703 struct seq_file *m = file->private_data; 704 struct namespace *namespace = m->private; 705 put_namespace(namespace); 706 return seq_release(inode, file); 707 } 708 709 static unsigned mounts_poll(struct file *file, poll_table *wait) 710 { 711 struct proc_mounts *p = file->private_data; 712 struct namespace *ns = p->m.private; 713 unsigned res = 0; 714 715 poll_wait(file, &ns->poll, wait); 716 717 spin_lock(&vfsmount_lock); 718 if (p->event != ns->event) { 719 p->event = ns->event; 720 res = POLLERR; 721 } 722 spin_unlock(&vfsmount_lock); 723 724 return res; 725 } 726 727 static struct file_operations proc_mounts_operations = { 728 .open = mounts_open, 729 .read = seq_read, 730 .llseek = seq_lseek, 731 .release = mounts_release, 732 .poll = mounts_poll, 733 }; 734 735 #define PROC_BLOCK_SIZE (3*1024) /* 4K page size but our output routines use some slack for overruns */ 736 737 static ssize_t proc_info_read(struct file * file, char __user * buf, 738 size_t count, loff_t *ppos) 739 { 740 struct inode * inode = file->f_dentry->d_inode; 741 unsigned long page; 742 ssize_t length; 743 struct task_struct *task = proc_task(inode); 744 745 if (count > PROC_BLOCK_SIZE) 746 count = PROC_BLOCK_SIZE; 747 if (!(page = __get_free_page(GFP_KERNEL))) 748 return -ENOMEM; 749 750 length = PROC_I(inode)->op.proc_read(task, (char*)page); 751 752 if (length >= 0) 753 length = simple_read_from_buffer(buf, count, ppos, (char *)page, length); 754 free_page(page); 755 return length; 756 } 757 758 static struct file_operations proc_info_file_operations = { 759 .read = proc_info_read, 760 }; 761 762 static int mem_open(struct inode* inode, struct file* file) 763 { 764 file->private_data = (void*)((long)current->self_exec_id); 765 return 0; 766 } 767 768 static ssize_t mem_read(struct file * file, char __user * buf, 769 size_t count, loff_t *ppos) 770 { 771 struct task_struct *task = proc_task(file->f_dentry->d_inode); 772 char *page; 773 unsigned long src = *ppos; 774 int ret = -ESRCH; 775 struct mm_struct *mm; 776 777 if (!MAY_PTRACE(task) || !ptrace_may_attach(task)) 778 goto out; 779 780 ret = -ENOMEM; 781 page = (char *)__get_free_page(GFP_USER); 782 if (!page) 783 goto out; 784 785 ret = 0; 786 787 mm = get_task_mm(task); 788 if (!mm) 789 goto out_free; 790 791 ret = -EIO; 792 793 if (file->private_data != (void*)((long)current->self_exec_id)) 794 goto out_put; 795 796 ret = 0; 797 798 while (count > 0) { 799 int this_len, retval; 800 801 this_len = (count > PAGE_SIZE) ? PAGE_SIZE : count; 802 retval = access_process_vm(task, src, page, this_len, 0); 803 if (!retval || !MAY_PTRACE(task) || !ptrace_may_attach(task)) { 804 if (!ret) 805 ret = -EIO; 806 break; 807 } 808 809 if (copy_to_user(buf, page, retval)) { 810 ret = -EFAULT; 811 break; 812 } 813 814 ret += retval; 815 src += retval; 816 buf += retval; 817 count -= retval; 818 } 819 *ppos = src; 820 821 out_put: 822 mmput(mm); 823 out_free: 824 free_page((unsigned long) page); 825 out: 826 return ret; 827 } 828 829 #define mem_write NULL 830 831 #ifndef mem_write 832 /* This is a security hazard */ 833 static ssize_t mem_write(struct file * file, const char * buf, 834 size_t count, loff_t *ppos) 835 { 836 int copied = 0; 837 char *page; 838 struct task_struct *task = proc_task(file->f_dentry->d_inode); 839 unsigned long dst = *ppos; 840 841 if (!MAY_PTRACE(task) || !ptrace_may_attach(task)) 842 return -ESRCH; 843 844 page = (char *)__get_free_page(GFP_USER); 845 if (!page) 846 return -ENOMEM; 847 848 while (count > 0) { 849 int this_len, retval; 850 851 this_len = (count > PAGE_SIZE) ? PAGE_SIZE : count; 852 if (copy_from_user(page, buf, this_len)) { 853 copied = -EFAULT; 854 break; 855 } 856 retval = access_process_vm(task, dst, page, this_len, 1); 857 if (!retval) { 858 if (!copied) 859 copied = -EIO; 860 break; 861 } 862 copied += retval; 863 buf += retval; 864 dst += retval; 865 count -= retval; 866 } 867 *ppos = dst; 868 free_page((unsigned long) page); 869 return copied; 870 } 871 #endif 872 873 static loff_t mem_lseek(struct file * file, loff_t offset, int orig) 874 { 875 switch (orig) { 876 case 0: 877 file->f_pos = offset; 878 break; 879 case 1: 880 file->f_pos += offset; 881 break; 882 default: 883 return -EINVAL; 884 } 885 force_successful_syscall_return(); 886 return file->f_pos; 887 } 888 889 static struct file_operations proc_mem_operations = { 890 .llseek = mem_lseek, 891 .read = mem_read, 892 .write = mem_write, 893 .open = mem_open, 894 }; 895 896 static ssize_t oom_adjust_read(struct file *file, char __user *buf, 897 size_t count, loff_t *ppos) 898 { 899 struct task_struct *task = proc_task(file->f_dentry->d_inode); 900 char buffer[8]; 901 size_t len; 902 int oom_adjust = task->oomkilladj; 903 loff_t __ppos = *ppos; 904 905 len = sprintf(buffer, "%i\n", oom_adjust); 906 if (__ppos >= len) 907 return 0; 908 if (count > len-__ppos) 909 count = len-__ppos; 910 if (copy_to_user(buf, buffer + __ppos, count)) 911 return -EFAULT; 912 *ppos = __ppos + count; 913 return count; 914 } 915 916 static ssize_t oom_adjust_write(struct file *file, const char __user *buf, 917 size_t count, loff_t *ppos) 918 { 919 struct task_struct *task = proc_task(file->f_dentry->d_inode); 920 char buffer[8], *end; 921 int oom_adjust; 922 923 if (!capable(CAP_SYS_RESOURCE)) 924 return -EPERM; 925 memset(buffer, 0, 8); 926 if (count > 6) 927 count = 6; 928 if (copy_from_user(buffer, buf, count)) 929 return -EFAULT; 930 oom_adjust = simple_strtol(buffer, &end, 0); 931 if ((oom_adjust < -16 || oom_adjust > 15) && oom_adjust != OOM_DISABLE) 932 return -EINVAL; 933 if (*end == '\n') 934 end++; 935 task->oomkilladj = oom_adjust; 936 if (end - buffer == 0) 937 return -EIO; 938 return end - buffer; 939 } 940 941 static struct file_operations proc_oom_adjust_operations = { 942 .read = oom_adjust_read, 943 .write = oom_adjust_write, 944 }; 945 946 static struct inode_operations proc_mem_inode_operations = { 947 .permission = proc_permission, 948 }; 949 950 #ifdef CONFIG_AUDITSYSCALL 951 #define TMPBUFLEN 21 952 static ssize_t proc_loginuid_read(struct file * file, char __user * buf, 953 size_t count, loff_t *ppos) 954 { 955 struct inode * inode = file->f_dentry->d_inode; 956 struct task_struct *task = proc_task(inode); 957 ssize_t length; 958 char tmpbuf[TMPBUFLEN]; 959 960 length = scnprintf(tmpbuf, TMPBUFLEN, "%u", 961 audit_get_loginuid(task->audit_context)); 962 return simple_read_from_buffer(buf, count, ppos, tmpbuf, length); 963 } 964 965 static ssize_t proc_loginuid_write(struct file * file, const char __user * buf, 966 size_t count, loff_t *ppos) 967 { 968 struct inode * inode = file->f_dentry->d_inode; 969 char *page, *tmp; 970 ssize_t length; 971 struct task_struct *task = proc_task(inode); 972 uid_t loginuid; 973 974 if (!capable(CAP_AUDIT_CONTROL)) 975 return -EPERM; 976 977 if (current != task) 978 return -EPERM; 979 980 if (count > PAGE_SIZE) 981 count = PAGE_SIZE; 982 983 if (*ppos != 0) { 984 /* No partial writes. */ 985 return -EINVAL; 986 } 987 page = (char*)__get_free_page(GFP_USER); 988 if (!page) 989 return -ENOMEM; 990 length = -EFAULT; 991 if (copy_from_user(page, buf, count)) 992 goto out_free_page; 993 994 loginuid = simple_strtoul(page, &tmp, 10); 995 if (tmp == page) { 996 length = -EINVAL; 997 goto out_free_page; 998 999 } 1000 length = audit_set_loginuid(task, loginuid); 1001 if (likely(length == 0)) 1002 length = count; 1003 1004 out_free_page: 1005 free_page((unsigned long) page); 1006 return length; 1007 } 1008 1009 static struct file_operations proc_loginuid_operations = { 1010 .read = proc_loginuid_read, 1011 .write = proc_loginuid_write, 1012 }; 1013 #endif 1014 1015 #ifdef CONFIG_SECCOMP 1016 static ssize_t seccomp_read(struct file *file, char __user *buf, 1017 size_t count, loff_t *ppos) 1018 { 1019 struct task_struct *tsk = proc_task(file->f_dentry->d_inode); 1020 char __buf[20]; 1021 loff_t __ppos = *ppos; 1022 size_t len; 1023 1024 /* no need to print the trailing zero, so use only len */ 1025 len = sprintf(__buf, "%u\n", tsk->seccomp.mode); 1026 if (__ppos >= len) 1027 return 0; 1028 if (count > len - __ppos) 1029 count = len - __ppos; 1030 if (copy_to_user(buf, __buf + __ppos, count)) 1031 return -EFAULT; 1032 *ppos = __ppos + count; 1033 return count; 1034 } 1035 1036 static ssize_t seccomp_write(struct file *file, const char __user *buf, 1037 size_t count, loff_t *ppos) 1038 { 1039 struct task_struct *tsk = proc_task(file->f_dentry->d_inode); 1040 char __buf[20], *end; 1041 unsigned int seccomp_mode; 1042 1043 /* can set it only once to be even more secure */ 1044 if (unlikely(tsk->seccomp.mode)) 1045 return -EPERM; 1046 1047 memset(__buf, 0, sizeof(__buf)); 1048 count = min(count, sizeof(__buf) - 1); 1049 if (copy_from_user(__buf, buf, count)) 1050 return -EFAULT; 1051 seccomp_mode = simple_strtoul(__buf, &end, 0); 1052 if (*end == '\n') 1053 end++; 1054 if (seccomp_mode && seccomp_mode <= NR_SECCOMP_MODES) { 1055 tsk->seccomp.mode = seccomp_mode; 1056 set_tsk_thread_flag(tsk, TIF_SECCOMP); 1057 } else 1058 return -EINVAL; 1059 if (unlikely(!(end - __buf))) 1060 return -EIO; 1061 return end - __buf; 1062 } 1063 1064 static struct file_operations proc_seccomp_operations = { 1065 .read = seccomp_read, 1066 .write = seccomp_write, 1067 }; 1068 #endif /* CONFIG_SECCOMP */ 1069 1070 static void *proc_pid_follow_link(struct dentry *dentry, struct nameidata *nd) 1071 { 1072 struct inode *inode = dentry->d_inode; 1073 int error = -EACCES; 1074 1075 /* We don't need a base pointer in the /proc filesystem */ 1076 path_release(nd); 1077 1078 if (current->fsuid != inode->i_uid && !capable(CAP_DAC_OVERRIDE)) 1079 goto out; 1080 error = proc_check_root(inode); 1081 if (error) 1082 goto out; 1083 1084 error = PROC_I(inode)->op.proc_get_link(inode, &nd->dentry, &nd->mnt); 1085 nd->last_type = LAST_BIND; 1086 out: 1087 return ERR_PTR(error); 1088 } 1089 1090 static int do_proc_readlink(struct dentry *dentry, struct vfsmount *mnt, 1091 char __user *buffer, int buflen) 1092 { 1093 struct inode * inode; 1094 char *tmp = (char*)__get_free_page(GFP_KERNEL), *path; 1095 int len; 1096 1097 if (!tmp) 1098 return -ENOMEM; 1099 1100 inode = dentry->d_inode; 1101 path = d_path(dentry, mnt, tmp, PAGE_SIZE); 1102 len = PTR_ERR(path); 1103 if (IS_ERR(path)) 1104 goto out; 1105 len = tmp + PAGE_SIZE - 1 - path; 1106 1107 if (len > buflen) 1108 len = buflen; 1109 if (copy_to_user(buffer, path, len)) 1110 len = -EFAULT; 1111 out: 1112 free_page((unsigned long)tmp); 1113 return len; 1114 } 1115 1116 static int proc_pid_readlink(struct dentry * dentry, char __user * buffer, int buflen) 1117 { 1118 int error = -EACCES; 1119 struct inode *inode = dentry->d_inode; 1120 struct dentry *de; 1121 struct vfsmount *mnt = NULL; 1122 1123 lock_kernel(); 1124 1125 if (current->fsuid != inode->i_uid && !capable(CAP_DAC_OVERRIDE)) 1126 goto out; 1127 error = proc_check_root(inode); 1128 if (error) 1129 goto out; 1130 1131 error = PROC_I(inode)->op.proc_get_link(inode, &de, &mnt); 1132 if (error) 1133 goto out; 1134 1135 error = do_proc_readlink(de, mnt, buffer, buflen); 1136 dput(de); 1137 mntput(mnt); 1138 out: 1139 unlock_kernel(); 1140 return error; 1141 } 1142 1143 static struct inode_operations proc_pid_link_inode_operations = { 1144 .readlink = proc_pid_readlink, 1145 .follow_link = proc_pid_follow_link 1146 }; 1147 1148 #define NUMBUF 10 1149 1150 static int proc_readfd(struct file * filp, void * dirent, filldir_t filldir) 1151 { 1152 struct inode *inode = filp->f_dentry->d_inode; 1153 struct task_struct *p = proc_task(inode); 1154 unsigned int fd, tid, ino; 1155 int retval; 1156 char buf[NUMBUF]; 1157 struct files_struct * files; 1158 struct fdtable *fdt; 1159 1160 retval = -ENOENT; 1161 if (!pid_alive(p)) 1162 goto out; 1163 retval = 0; 1164 tid = p->pid; 1165 1166 fd = filp->f_pos; 1167 switch (fd) { 1168 case 0: 1169 if (filldir(dirent, ".", 1, 0, inode->i_ino, DT_DIR) < 0) 1170 goto out; 1171 filp->f_pos++; 1172 case 1: 1173 ino = fake_ino(tid, PROC_TID_INO); 1174 if (filldir(dirent, "..", 2, 1, ino, DT_DIR) < 0) 1175 goto out; 1176 filp->f_pos++; 1177 default: 1178 files = get_files_struct(p); 1179 if (!files) 1180 goto out; 1181 rcu_read_lock(); 1182 fdt = files_fdtable(files); 1183 for (fd = filp->f_pos-2; 1184 fd < fdt->max_fds; 1185 fd++, filp->f_pos++) { 1186 unsigned int i,j; 1187 1188 if (!fcheck_files(files, fd)) 1189 continue; 1190 rcu_read_unlock(); 1191 1192 j = NUMBUF; 1193 i = fd; 1194 do { 1195 j--; 1196 buf[j] = '0' + (i % 10); 1197 i /= 10; 1198 } while (i); 1199 1200 ino = fake_ino(tid, PROC_TID_FD_DIR + fd); 1201 if (filldir(dirent, buf+j, NUMBUF-j, fd+2, ino, DT_LNK) < 0) { 1202 rcu_read_lock(); 1203 break; 1204 } 1205 rcu_read_lock(); 1206 } 1207 rcu_read_unlock(); 1208 put_files_struct(files); 1209 } 1210 out: 1211 return retval; 1212 } 1213 1214 static int proc_pident_readdir(struct file *filp, 1215 void *dirent, filldir_t filldir, 1216 struct pid_entry *ents, unsigned int nents) 1217 { 1218 int i; 1219 int pid; 1220 struct dentry *dentry = filp->f_dentry; 1221 struct inode *inode = dentry->d_inode; 1222 struct pid_entry *p; 1223 ino_t ino; 1224 int ret; 1225 1226 ret = -ENOENT; 1227 if (!pid_alive(proc_task(inode))) 1228 goto out; 1229 1230 ret = 0; 1231 pid = proc_task(inode)->pid; 1232 i = filp->f_pos; 1233 switch (i) { 1234 case 0: 1235 ino = inode->i_ino; 1236 if (filldir(dirent, ".", 1, i, ino, DT_DIR) < 0) 1237 goto out; 1238 i++; 1239 filp->f_pos++; 1240 /* fall through */ 1241 case 1: 1242 ino = parent_ino(dentry); 1243 if (filldir(dirent, "..", 2, i, ino, DT_DIR) < 0) 1244 goto out; 1245 i++; 1246 filp->f_pos++; 1247 /* fall through */ 1248 default: 1249 i -= 2; 1250 if (i >= nents) { 1251 ret = 1; 1252 goto out; 1253 } 1254 p = ents + i; 1255 while (p->name) { 1256 if (filldir(dirent, p->name, p->len, filp->f_pos, 1257 fake_ino(pid, p->type), p->mode >> 12) < 0) 1258 goto out; 1259 filp->f_pos++; 1260 p++; 1261 } 1262 } 1263 1264 ret = 1; 1265 out: 1266 return ret; 1267 } 1268 1269 static int proc_tgid_base_readdir(struct file * filp, 1270 void * dirent, filldir_t filldir) 1271 { 1272 return proc_pident_readdir(filp,dirent,filldir, 1273 tgid_base_stuff,ARRAY_SIZE(tgid_base_stuff)); 1274 } 1275 1276 static int proc_tid_base_readdir(struct file * filp, 1277 void * dirent, filldir_t filldir) 1278 { 1279 return proc_pident_readdir(filp,dirent,filldir, 1280 tid_base_stuff,ARRAY_SIZE(tid_base_stuff)); 1281 } 1282 1283 /* building an inode */ 1284 1285 static int task_dumpable(struct task_struct *task) 1286 { 1287 int dumpable = 0; 1288 struct mm_struct *mm; 1289 1290 task_lock(task); 1291 mm = task->mm; 1292 if (mm) 1293 dumpable = mm->dumpable; 1294 task_unlock(task); 1295 if(dumpable == 1) 1296 return 1; 1297 return 0; 1298 } 1299 1300 1301 static struct inode *proc_pid_make_inode(struct super_block * sb, struct task_struct *task, int ino) 1302 { 1303 struct inode * inode; 1304 struct proc_inode *ei; 1305 1306 /* We need a new inode */ 1307 1308 inode = new_inode(sb); 1309 if (!inode) 1310 goto out; 1311 1312 /* Common stuff */ 1313 ei = PROC_I(inode); 1314 ei->task = NULL; 1315 inode->i_mtime = inode->i_atime = inode->i_ctime = CURRENT_TIME; 1316 inode->i_ino = fake_ino(task->pid, ino); 1317 1318 if (!pid_alive(task)) 1319 goto out_unlock; 1320 1321 /* 1322 * grab the reference to task. 1323 */ 1324 get_task_struct(task); 1325 ei->task = task; 1326 ei->type = ino; 1327 inode->i_uid = 0; 1328 inode->i_gid = 0; 1329 if (ino == PROC_TGID_INO || ino == PROC_TID_INO || task_dumpable(task)) { 1330 inode->i_uid = task->euid; 1331 inode->i_gid = task->egid; 1332 } 1333 security_task_to_inode(task, inode); 1334 1335 out: 1336 return inode; 1337 1338 out_unlock: 1339 ei->pde = NULL; 1340 iput(inode); 1341 return NULL; 1342 } 1343 1344 /* dentry stuff */ 1345 1346 /* 1347 * Exceptional case: normally we are not allowed to unhash a busy 1348 * directory. In this case, however, we can do it - no aliasing problems 1349 * due to the way we treat inodes. 1350 * 1351 * Rewrite the inode's ownerships here because the owning task may have 1352 * performed a setuid(), etc. 1353 */ 1354 static int pid_revalidate(struct dentry *dentry, struct nameidata *nd) 1355 { 1356 struct inode *inode = dentry->d_inode; 1357 struct task_struct *task = proc_task(inode); 1358 if (pid_alive(task)) { 1359 if (proc_type(inode) == PROC_TGID_INO || proc_type(inode) == PROC_TID_INO || task_dumpable(task)) { 1360 inode->i_uid = task->euid; 1361 inode->i_gid = task->egid; 1362 } else { 1363 inode->i_uid = 0; 1364 inode->i_gid = 0; 1365 } 1366 security_task_to_inode(task, inode); 1367 return 1; 1368 } 1369 d_drop(dentry); 1370 return 0; 1371 } 1372 1373 static int tid_fd_revalidate(struct dentry *dentry, struct nameidata *nd) 1374 { 1375 struct inode *inode = dentry->d_inode; 1376 struct task_struct *task = proc_task(inode); 1377 int fd = proc_type(inode) - PROC_TID_FD_DIR; 1378 struct files_struct *files; 1379 1380 files = get_files_struct(task); 1381 if (files) { 1382 rcu_read_lock(); 1383 if (fcheck_files(files, fd)) { 1384 rcu_read_unlock(); 1385 put_files_struct(files); 1386 if (task_dumpable(task)) { 1387 inode->i_uid = task->euid; 1388 inode->i_gid = task->egid; 1389 } else { 1390 inode->i_uid = 0; 1391 inode->i_gid = 0; 1392 } 1393 security_task_to_inode(task, inode); 1394 return 1; 1395 } 1396 rcu_read_unlock(); 1397 put_files_struct(files); 1398 } 1399 d_drop(dentry); 1400 return 0; 1401 } 1402 1403 static void pid_base_iput(struct dentry *dentry, struct inode *inode) 1404 { 1405 struct task_struct *task = proc_task(inode); 1406 spin_lock(&task->proc_lock); 1407 if (task->proc_dentry == dentry) 1408 task->proc_dentry = NULL; 1409 spin_unlock(&task->proc_lock); 1410 iput(inode); 1411 } 1412 1413 static int pid_delete_dentry(struct dentry * dentry) 1414 { 1415 /* Is the task we represent dead? 1416 * If so, then don't put the dentry on the lru list, 1417 * kill it immediately. 1418 */ 1419 return !pid_alive(proc_task(dentry->d_inode)); 1420 } 1421 1422 static struct dentry_operations tid_fd_dentry_operations = 1423 { 1424 .d_revalidate = tid_fd_revalidate, 1425 .d_delete = pid_delete_dentry, 1426 }; 1427 1428 static struct dentry_operations pid_dentry_operations = 1429 { 1430 .d_revalidate = pid_revalidate, 1431 .d_delete = pid_delete_dentry, 1432 }; 1433 1434 static struct dentry_operations pid_base_dentry_operations = 1435 { 1436 .d_revalidate = pid_revalidate, 1437 .d_iput = pid_base_iput, 1438 .d_delete = pid_delete_dentry, 1439 }; 1440 1441 /* Lookups */ 1442 1443 static unsigned name_to_int(struct dentry *dentry) 1444 { 1445 const char *name = dentry->d_name.name; 1446 int len = dentry->d_name.len; 1447 unsigned n = 0; 1448 1449 if (len > 1 && *name == '0') 1450 goto out; 1451 while (len-- > 0) { 1452 unsigned c = *name++ - '0'; 1453 if (c > 9) 1454 goto out; 1455 if (n >= (~0U-9)/10) 1456 goto out; 1457 n *= 10; 1458 n += c; 1459 } 1460 return n; 1461 out: 1462 return ~0U; 1463 } 1464 1465 /* SMP-safe */ 1466 static struct dentry *proc_lookupfd(struct inode * dir, struct dentry * dentry, struct nameidata *nd) 1467 { 1468 struct task_struct *task = proc_task(dir); 1469 unsigned fd = name_to_int(dentry); 1470 struct file * file; 1471 struct files_struct * files; 1472 struct inode *inode; 1473 struct proc_inode *ei; 1474 1475 if (fd == ~0U) 1476 goto out; 1477 if (!pid_alive(task)) 1478 goto out; 1479 1480 inode = proc_pid_make_inode(dir->i_sb, task, PROC_TID_FD_DIR+fd); 1481 if (!inode) 1482 goto out; 1483 ei = PROC_I(inode); 1484 files = get_files_struct(task); 1485 if (!files) 1486 goto out_unlock; 1487 inode->i_mode = S_IFLNK; 1488 rcu_read_lock(); 1489 file = fcheck_files(files, fd); 1490 if (!file) 1491 goto out_unlock2; 1492 if (file->f_mode & 1) 1493 inode->i_mode |= S_IRUSR | S_IXUSR; 1494 if (file->f_mode & 2) 1495 inode->i_mode |= S_IWUSR | S_IXUSR; 1496 rcu_read_unlock(); 1497 put_files_struct(files); 1498 inode->i_op = &proc_pid_link_inode_operations; 1499 inode->i_size = 64; 1500 ei->op.proc_get_link = proc_fd_link; 1501 dentry->d_op = &tid_fd_dentry_operations; 1502 d_add(dentry, inode); 1503 return NULL; 1504 1505 out_unlock2: 1506 rcu_read_unlock(); 1507 put_files_struct(files); 1508 out_unlock: 1509 iput(inode); 1510 out: 1511 return ERR_PTR(-ENOENT); 1512 } 1513 1514 static int proc_task_readdir(struct file * filp, void * dirent, filldir_t filldir); 1515 static struct dentry *proc_task_lookup(struct inode *dir, struct dentry * dentry, struct nameidata *nd); 1516 1517 static struct file_operations proc_fd_operations = { 1518 .read = generic_read_dir, 1519 .readdir = proc_readfd, 1520 }; 1521 1522 static struct file_operations proc_task_operations = { 1523 .read = generic_read_dir, 1524 .readdir = proc_task_readdir, 1525 }; 1526 1527 /* 1528 * proc directories can do almost nothing.. 1529 */ 1530 static struct inode_operations proc_fd_inode_operations = { 1531 .lookup = proc_lookupfd, 1532 .permission = proc_permission, 1533 }; 1534 1535 static struct inode_operations proc_task_inode_operations = { 1536 .lookup = proc_task_lookup, 1537 .permission = proc_task_permission, 1538 }; 1539 1540 #ifdef CONFIG_SECURITY 1541 static ssize_t proc_pid_attr_read(struct file * file, char __user * buf, 1542 size_t count, loff_t *ppos) 1543 { 1544 struct inode * inode = file->f_dentry->d_inode; 1545 unsigned long page; 1546 ssize_t length; 1547 struct task_struct *task = proc_task(inode); 1548 1549 if (count > PAGE_SIZE) 1550 count = PAGE_SIZE; 1551 if (!(page = __get_free_page(GFP_KERNEL))) 1552 return -ENOMEM; 1553 1554 length = security_getprocattr(task, 1555 (char*)file->f_dentry->d_name.name, 1556 (void*)page, count); 1557 if (length >= 0) 1558 length = simple_read_from_buffer(buf, count, ppos, (char *)page, length); 1559 free_page(page); 1560 return length; 1561 } 1562 1563 static ssize_t proc_pid_attr_write(struct file * file, const char __user * buf, 1564 size_t count, loff_t *ppos) 1565 { 1566 struct inode * inode = file->f_dentry->d_inode; 1567 char *page; 1568 ssize_t length; 1569 struct task_struct *task = proc_task(inode); 1570 1571 if (count > PAGE_SIZE) 1572 count = PAGE_SIZE; 1573 if (*ppos != 0) { 1574 /* No partial writes. */ 1575 return -EINVAL; 1576 } 1577 page = (char*)__get_free_page(GFP_USER); 1578 if (!page) 1579 return -ENOMEM; 1580 length = -EFAULT; 1581 if (copy_from_user(page, buf, count)) 1582 goto out; 1583 1584 length = security_setprocattr(task, 1585 (char*)file->f_dentry->d_name.name, 1586 (void*)page, count); 1587 out: 1588 free_page((unsigned long) page); 1589 return length; 1590 } 1591 1592 static struct file_operations proc_pid_attr_operations = { 1593 .read = proc_pid_attr_read, 1594 .write = proc_pid_attr_write, 1595 }; 1596 1597 static struct file_operations proc_tid_attr_operations; 1598 static struct inode_operations proc_tid_attr_inode_operations; 1599 static struct file_operations proc_tgid_attr_operations; 1600 static struct inode_operations proc_tgid_attr_inode_operations; 1601 #endif 1602 1603 static int get_tid_list(int index, unsigned int *tids, struct inode *dir); 1604 1605 /* SMP-safe */ 1606 static struct dentry *proc_pident_lookup(struct inode *dir, 1607 struct dentry *dentry, 1608 struct pid_entry *ents) 1609 { 1610 struct inode *inode; 1611 int error; 1612 struct task_struct *task = proc_task(dir); 1613 struct pid_entry *p; 1614 struct proc_inode *ei; 1615 1616 error = -ENOENT; 1617 inode = NULL; 1618 1619 if (!pid_alive(task)) 1620 goto out; 1621 1622 for (p = ents; p->name; p++) { 1623 if (p->len != dentry->d_name.len) 1624 continue; 1625 if (!memcmp(dentry->d_name.name, p->name, p->len)) 1626 break; 1627 } 1628 if (!p->name) 1629 goto out; 1630 1631 error = -EINVAL; 1632 inode = proc_pid_make_inode(dir->i_sb, task, p->type); 1633 if (!inode) 1634 goto out; 1635 1636 ei = PROC_I(inode); 1637 inode->i_mode = p->mode; 1638 /* 1639 * Yes, it does not scale. And it should not. Don't add 1640 * new entries into /proc/<tgid>/ without very good reasons. 1641 */ 1642 switch(p->type) { 1643 case PROC_TGID_TASK: 1644 inode->i_nlink = 2 + get_tid_list(2, NULL, dir); 1645 inode->i_op = &proc_task_inode_operations; 1646 inode->i_fop = &proc_task_operations; 1647 break; 1648 case PROC_TID_FD: 1649 case PROC_TGID_FD: 1650 inode->i_nlink = 2; 1651 inode->i_op = &proc_fd_inode_operations; 1652 inode->i_fop = &proc_fd_operations; 1653 break; 1654 case PROC_TID_EXE: 1655 case PROC_TGID_EXE: 1656 inode->i_op = &proc_pid_link_inode_operations; 1657 ei->op.proc_get_link = proc_exe_link; 1658 break; 1659 case PROC_TID_CWD: 1660 case PROC_TGID_CWD: 1661 inode->i_op = &proc_pid_link_inode_operations; 1662 ei->op.proc_get_link = proc_cwd_link; 1663 break; 1664 case PROC_TID_ROOT: 1665 case PROC_TGID_ROOT: 1666 inode->i_op = &proc_pid_link_inode_operations; 1667 ei->op.proc_get_link = proc_root_link; 1668 break; 1669 case PROC_TID_ENVIRON: 1670 case PROC_TGID_ENVIRON: 1671 inode->i_fop = &proc_info_file_operations; 1672 ei->op.proc_read = proc_pid_environ; 1673 break; 1674 case PROC_TID_AUXV: 1675 case PROC_TGID_AUXV: 1676 inode->i_fop = &proc_info_file_operations; 1677 ei->op.proc_read = proc_pid_auxv; 1678 break; 1679 case PROC_TID_STATUS: 1680 case PROC_TGID_STATUS: 1681 inode->i_fop = &proc_info_file_operations; 1682 ei->op.proc_read = proc_pid_status; 1683 break; 1684 case PROC_TID_STAT: 1685 inode->i_fop = &proc_info_file_operations; 1686 ei->op.proc_read = proc_tid_stat; 1687 break; 1688 case PROC_TGID_STAT: 1689 inode->i_fop = &proc_info_file_operations; 1690 ei->op.proc_read = proc_tgid_stat; 1691 break; 1692 case PROC_TID_CMDLINE: 1693 case PROC_TGID_CMDLINE: 1694 inode->i_fop = &proc_info_file_operations; 1695 ei->op.proc_read = proc_pid_cmdline; 1696 break; 1697 case PROC_TID_STATM: 1698 case PROC_TGID_STATM: 1699 inode->i_fop = &proc_info_file_operations; 1700 ei->op.proc_read = proc_pid_statm; 1701 break; 1702 case PROC_TID_MAPS: 1703 case PROC_TGID_MAPS: 1704 inode->i_fop = &proc_maps_operations; 1705 break; 1706 #ifdef CONFIG_NUMA 1707 case PROC_TID_NUMA_MAPS: 1708 case PROC_TGID_NUMA_MAPS: 1709 inode->i_fop = &proc_numa_maps_operations; 1710 break; 1711 #endif 1712 case PROC_TID_MEM: 1713 case PROC_TGID_MEM: 1714 inode->i_op = &proc_mem_inode_operations; 1715 inode->i_fop = &proc_mem_operations; 1716 break; 1717 #ifdef CONFIG_SECCOMP 1718 case PROC_TID_SECCOMP: 1719 case PROC_TGID_SECCOMP: 1720 inode->i_fop = &proc_seccomp_operations; 1721 break; 1722 #endif /* CONFIG_SECCOMP */ 1723 case PROC_TID_MOUNTS: 1724 case PROC_TGID_MOUNTS: 1725 inode->i_fop = &proc_mounts_operations; 1726 break; 1727 #ifdef CONFIG_MMU 1728 case PROC_TID_SMAPS: 1729 case PROC_TGID_SMAPS: 1730 inode->i_fop = &proc_smaps_operations; 1731 break; 1732 #endif 1733 #ifdef CONFIG_SECURITY 1734 case PROC_TID_ATTR: 1735 inode->i_nlink = 2; 1736 inode->i_op = &proc_tid_attr_inode_operations; 1737 inode->i_fop = &proc_tid_attr_operations; 1738 break; 1739 case PROC_TGID_ATTR: 1740 inode->i_nlink = 2; 1741 inode->i_op = &proc_tgid_attr_inode_operations; 1742 inode->i_fop = &proc_tgid_attr_operations; 1743 break; 1744 case PROC_TID_ATTR_CURRENT: 1745 case PROC_TGID_ATTR_CURRENT: 1746 case PROC_TID_ATTR_PREV: 1747 case PROC_TGID_ATTR_PREV: 1748 case PROC_TID_ATTR_EXEC: 1749 case PROC_TGID_ATTR_EXEC: 1750 case PROC_TID_ATTR_FSCREATE: 1751 case PROC_TGID_ATTR_FSCREATE: 1752 inode->i_fop = &proc_pid_attr_operations; 1753 break; 1754 #endif 1755 #ifdef CONFIG_KALLSYMS 1756 case PROC_TID_WCHAN: 1757 case PROC_TGID_WCHAN: 1758 inode->i_fop = &proc_info_file_operations; 1759 ei->op.proc_read = proc_pid_wchan; 1760 break; 1761 #endif 1762 #ifdef CONFIG_SCHEDSTATS 1763 case PROC_TID_SCHEDSTAT: 1764 case PROC_TGID_SCHEDSTAT: 1765 inode->i_fop = &proc_info_file_operations; 1766 ei->op.proc_read = proc_pid_schedstat; 1767 break; 1768 #endif 1769 #ifdef CONFIG_CPUSETS 1770 case PROC_TID_CPUSET: 1771 case PROC_TGID_CPUSET: 1772 inode->i_fop = &proc_cpuset_operations; 1773 break; 1774 #endif 1775 case PROC_TID_OOM_SCORE: 1776 case PROC_TGID_OOM_SCORE: 1777 inode->i_fop = &proc_info_file_operations; 1778 ei->op.proc_read = proc_oom_score; 1779 break; 1780 case PROC_TID_OOM_ADJUST: 1781 case PROC_TGID_OOM_ADJUST: 1782 inode->i_fop = &proc_oom_adjust_operations; 1783 break; 1784 #ifdef CONFIG_AUDITSYSCALL 1785 case PROC_TID_LOGINUID: 1786 case PROC_TGID_LOGINUID: 1787 inode->i_fop = &proc_loginuid_operations; 1788 break; 1789 #endif 1790 default: 1791 printk("procfs: impossible type (%d)",p->type); 1792 iput(inode); 1793 return ERR_PTR(-EINVAL); 1794 } 1795 dentry->d_op = &pid_dentry_operations; 1796 d_add(dentry, inode); 1797 return NULL; 1798 1799 out: 1800 return ERR_PTR(error); 1801 } 1802 1803 static struct dentry *proc_tgid_base_lookup(struct inode *dir, struct dentry *dentry, struct nameidata *nd){ 1804 return proc_pident_lookup(dir, dentry, tgid_base_stuff); 1805 } 1806 1807 static struct dentry *proc_tid_base_lookup(struct inode *dir, struct dentry *dentry, struct nameidata *nd){ 1808 return proc_pident_lookup(dir, dentry, tid_base_stuff); 1809 } 1810 1811 static struct file_operations proc_tgid_base_operations = { 1812 .read = generic_read_dir, 1813 .readdir = proc_tgid_base_readdir, 1814 }; 1815 1816 static struct file_operations proc_tid_base_operations = { 1817 .read = generic_read_dir, 1818 .readdir = proc_tid_base_readdir, 1819 }; 1820 1821 static struct inode_operations proc_tgid_base_inode_operations = { 1822 .lookup = proc_tgid_base_lookup, 1823 }; 1824 1825 static struct inode_operations proc_tid_base_inode_operations = { 1826 .lookup = proc_tid_base_lookup, 1827 }; 1828 1829 #ifdef CONFIG_SECURITY 1830 static int proc_tgid_attr_readdir(struct file * filp, 1831 void * dirent, filldir_t filldir) 1832 { 1833 return proc_pident_readdir(filp,dirent,filldir, 1834 tgid_attr_stuff,ARRAY_SIZE(tgid_attr_stuff)); 1835 } 1836 1837 static int proc_tid_attr_readdir(struct file * filp, 1838 void * dirent, filldir_t filldir) 1839 { 1840 return proc_pident_readdir(filp,dirent,filldir, 1841 tid_attr_stuff,ARRAY_SIZE(tid_attr_stuff)); 1842 } 1843 1844 static struct file_operations proc_tgid_attr_operations = { 1845 .read = generic_read_dir, 1846 .readdir = proc_tgid_attr_readdir, 1847 }; 1848 1849 static struct file_operations proc_tid_attr_operations = { 1850 .read = generic_read_dir, 1851 .readdir = proc_tid_attr_readdir, 1852 }; 1853 1854 static struct dentry *proc_tgid_attr_lookup(struct inode *dir, 1855 struct dentry *dentry, struct nameidata *nd) 1856 { 1857 return proc_pident_lookup(dir, dentry, tgid_attr_stuff); 1858 } 1859 1860 static struct dentry *proc_tid_attr_lookup(struct inode *dir, 1861 struct dentry *dentry, struct nameidata *nd) 1862 { 1863 return proc_pident_lookup(dir, dentry, tid_attr_stuff); 1864 } 1865 1866 static struct inode_operations proc_tgid_attr_inode_operations = { 1867 .lookup = proc_tgid_attr_lookup, 1868 }; 1869 1870 static struct inode_operations proc_tid_attr_inode_operations = { 1871 .lookup = proc_tid_attr_lookup, 1872 }; 1873 #endif 1874 1875 /* 1876 * /proc/self: 1877 */ 1878 static int proc_self_readlink(struct dentry *dentry, char __user *buffer, 1879 int buflen) 1880 { 1881 char tmp[30]; 1882 sprintf(tmp, "%d", current->tgid); 1883 return vfs_readlink(dentry,buffer,buflen,tmp); 1884 } 1885 1886 static void *proc_self_follow_link(struct dentry *dentry, struct nameidata *nd) 1887 { 1888 char tmp[30]; 1889 sprintf(tmp, "%d", current->tgid); 1890 return ERR_PTR(vfs_follow_link(nd,tmp)); 1891 } 1892 1893 static struct inode_operations proc_self_inode_operations = { 1894 .readlink = proc_self_readlink, 1895 .follow_link = proc_self_follow_link, 1896 }; 1897 1898 /** 1899 * proc_pid_unhash - Unhash /proc/@pid entry from the dcache. 1900 * @p: task that should be flushed. 1901 * 1902 * Drops the /proc/@pid dcache entry from the hash chains. 1903 * 1904 * Dropping /proc/@pid entries and detach_pid must be synchroneous, 1905 * otherwise e.g. /proc/@pid/exe might point to the wrong executable, 1906 * if the pid value is immediately reused. This is enforced by 1907 * - caller must acquire spin_lock(p->proc_lock) 1908 * - must be called before detach_pid() 1909 * - proc_pid_lookup acquires proc_lock, and checks that 1910 * the target is not dead by looking at the attach count 1911 * of PIDTYPE_PID. 1912 */ 1913 1914 struct dentry *proc_pid_unhash(struct task_struct *p) 1915 { 1916 struct dentry *proc_dentry; 1917 1918 proc_dentry = p->proc_dentry; 1919 if (proc_dentry != NULL) { 1920 1921 spin_lock(&dcache_lock); 1922 spin_lock(&proc_dentry->d_lock); 1923 if (!d_unhashed(proc_dentry)) { 1924 dget_locked(proc_dentry); 1925 __d_drop(proc_dentry); 1926 spin_unlock(&proc_dentry->d_lock); 1927 } else { 1928 spin_unlock(&proc_dentry->d_lock); 1929 proc_dentry = NULL; 1930 } 1931 spin_unlock(&dcache_lock); 1932 } 1933 return proc_dentry; 1934 } 1935 1936 /** 1937 * proc_pid_flush - recover memory used by stale /proc/@pid/x entries 1938 * @proc_dentry: directoy to prune. 1939 * 1940 * Shrink the /proc directory that was used by the just killed thread. 1941 */ 1942 1943 void proc_pid_flush(struct dentry *proc_dentry) 1944 { 1945 might_sleep(); 1946 if(proc_dentry != NULL) { 1947 shrink_dcache_parent(proc_dentry); 1948 dput(proc_dentry); 1949 } 1950 } 1951 1952 /* SMP-safe */ 1953 struct dentry *proc_pid_lookup(struct inode *dir, struct dentry * dentry, struct nameidata *nd) 1954 { 1955 struct task_struct *task; 1956 struct inode *inode; 1957 struct proc_inode *ei; 1958 unsigned tgid; 1959 int died; 1960 1961 if (dentry->d_name.len == 4 && !memcmp(dentry->d_name.name,"self",4)) { 1962 inode = new_inode(dir->i_sb); 1963 if (!inode) 1964 return ERR_PTR(-ENOMEM); 1965 ei = PROC_I(inode); 1966 inode->i_mtime = inode->i_atime = inode->i_ctime = CURRENT_TIME; 1967 inode->i_ino = fake_ino(0, PROC_TGID_INO); 1968 ei->pde = NULL; 1969 inode->i_mode = S_IFLNK|S_IRWXUGO; 1970 inode->i_uid = inode->i_gid = 0; 1971 inode->i_size = 64; 1972 inode->i_op = &proc_self_inode_operations; 1973 d_add(dentry, inode); 1974 return NULL; 1975 } 1976 tgid = name_to_int(dentry); 1977 if (tgid == ~0U) 1978 goto out; 1979 1980 read_lock(&tasklist_lock); 1981 task = find_task_by_pid(tgid); 1982 if (task) 1983 get_task_struct(task); 1984 read_unlock(&tasklist_lock); 1985 if (!task) 1986 goto out; 1987 1988 inode = proc_pid_make_inode(dir->i_sb, task, PROC_TGID_INO); 1989 1990 1991 if (!inode) { 1992 put_task_struct(task); 1993 goto out; 1994 } 1995 inode->i_mode = S_IFDIR|S_IRUGO|S_IXUGO; 1996 inode->i_op = &proc_tgid_base_inode_operations; 1997 inode->i_fop = &proc_tgid_base_operations; 1998 inode->i_flags|=S_IMMUTABLE; 1999 #ifdef CONFIG_SECURITY 2000 inode->i_nlink = 5; 2001 #else 2002 inode->i_nlink = 4; 2003 #endif 2004 2005 dentry->d_op = &pid_base_dentry_operations; 2006 2007 died = 0; 2008 d_add(dentry, inode); 2009 spin_lock(&task->proc_lock); 2010 task->proc_dentry = dentry; 2011 if (!pid_alive(task)) { 2012 dentry = proc_pid_unhash(task); 2013 died = 1; 2014 } 2015 spin_unlock(&task->proc_lock); 2016 2017 put_task_struct(task); 2018 if (died) { 2019 proc_pid_flush(dentry); 2020 goto out; 2021 } 2022 return NULL; 2023 out: 2024 return ERR_PTR(-ENOENT); 2025 } 2026 2027 /* SMP-safe */ 2028 static struct dentry *proc_task_lookup(struct inode *dir, struct dentry * dentry, struct nameidata *nd) 2029 { 2030 struct task_struct *task; 2031 struct task_struct *leader = proc_task(dir); 2032 struct inode *inode; 2033 unsigned tid; 2034 2035 tid = name_to_int(dentry); 2036 if (tid == ~0U) 2037 goto out; 2038 2039 read_lock(&tasklist_lock); 2040 task = find_task_by_pid(tid); 2041 if (task) 2042 get_task_struct(task); 2043 read_unlock(&tasklist_lock); 2044 if (!task) 2045 goto out; 2046 if (leader->tgid != task->tgid) 2047 goto out_drop_task; 2048 2049 inode = proc_pid_make_inode(dir->i_sb, task, PROC_TID_INO); 2050 2051 2052 if (!inode) 2053 goto out_drop_task; 2054 inode->i_mode = S_IFDIR|S_IRUGO|S_IXUGO; 2055 inode->i_op = &proc_tid_base_inode_operations; 2056 inode->i_fop = &proc_tid_base_operations; 2057 inode->i_flags|=S_IMMUTABLE; 2058 #ifdef CONFIG_SECURITY 2059 inode->i_nlink = 4; 2060 #else 2061 inode->i_nlink = 3; 2062 #endif 2063 2064 dentry->d_op = &pid_base_dentry_operations; 2065 2066 d_add(dentry, inode); 2067 2068 put_task_struct(task); 2069 return NULL; 2070 out_drop_task: 2071 put_task_struct(task); 2072 out: 2073 return ERR_PTR(-ENOENT); 2074 } 2075 2076 #define PROC_NUMBUF 10 2077 #define PROC_MAXPIDS 20 2078 2079 /* 2080 * Get a few tgid's to return for filldir - we need to hold the 2081 * tasklist lock while doing this, and we must release it before 2082 * we actually do the filldir itself, so we use a temp buffer.. 2083 */ 2084 static int get_tgid_list(int index, unsigned long version, unsigned int *tgids) 2085 { 2086 struct task_struct *p; 2087 int nr_tgids = 0; 2088 2089 index--; 2090 read_lock(&tasklist_lock); 2091 p = NULL; 2092 if (version) { 2093 p = find_task_by_pid(version); 2094 if (p && !thread_group_leader(p)) 2095 p = NULL; 2096 } 2097 2098 if (p) 2099 index = 0; 2100 else 2101 p = next_task(&init_task); 2102 2103 for ( ; p != &init_task; p = next_task(p)) { 2104 int tgid = p->pid; 2105 if (!pid_alive(p)) 2106 continue; 2107 if (--index >= 0) 2108 continue; 2109 tgids[nr_tgids] = tgid; 2110 nr_tgids++; 2111 if (nr_tgids >= PROC_MAXPIDS) 2112 break; 2113 } 2114 read_unlock(&tasklist_lock); 2115 return nr_tgids; 2116 } 2117 2118 /* 2119 * Get a few tid's to return for filldir - we need to hold the 2120 * tasklist lock while doing this, and we must release it before 2121 * we actually do the filldir itself, so we use a temp buffer.. 2122 */ 2123 static int get_tid_list(int index, unsigned int *tids, struct inode *dir) 2124 { 2125 struct task_struct *leader_task = proc_task(dir); 2126 struct task_struct *task = leader_task; 2127 int nr_tids = 0; 2128 2129 index -= 2; 2130 read_lock(&tasklist_lock); 2131 /* 2132 * The starting point task (leader_task) might be an already 2133 * unlinked task, which cannot be used to access the task-list 2134 * via next_thread(). 2135 */ 2136 if (pid_alive(task)) do { 2137 int tid = task->pid; 2138 2139 if (--index >= 0) 2140 continue; 2141 if (tids != NULL) 2142 tids[nr_tids] = tid; 2143 nr_tids++; 2144 if (nr_tids >= PROC_MAXPIDS) 2145 break; 2146 } while ((task = next_thread(task)) != leader_task); 2147 read_unlock(&tasklist_lock); 2148 return nr_tids; 2149 } 2150 2151 /* for the /proc/ directory itself, after non-process stuff has been done */ 2152 int proc_pid_readdir(struct file * filp, void * dirent, filldir_t filldir) 2153 { 2154 unsigned int tgid_array[PROC_MAXPIDS]; 2155 char buf[PROC_NUMBUF]; 2156 unsigned int nr = filp->f_pos - FIRST_PROCESS_ENTRY; 2157 unsigned int nr_tgids, i; 2158 int next_tgid; 2159 2160 if (!nr) { 2161 ino_t ino = fake_ino(0,PROC_TGID_INO); 2162 if (filldir(dirent, "self", 4, filp->f_pos, ino, DT_LNK) < 0) 2163 return 0; 2164 filp->f_pos++; 2165 nr++; 2166 } 2167 2168 /* f_version caches the tgid value that the last readdir call couldn't 2169 * return. lseek aka telldir automagically resets f_version to 0. 2170 */ 2171 next_tgid = filp->f_version; 2172 filp->f_version = 0; 2173 for (;;) { 2174 nr_tgids = get_tgid_list(nr, next_tgid, tgid_array); 2175 if (!nr_tgids) { 2176 /* no more entries ! */ 2177 break; 2178 } 2179 next_tgid = 0; 2180 2181 /* do not use the last found pid, reserve it for next_tgid */ 2182 if (nr_tgids == PROC_MAXPIDS) { 2183 nr_tgids--; 2184 next_tgid = tgid_array[nr_tgids]; 2185 } 2186 2187 for (i=0;i<nr_tgids;i++) { 2188 int tgid = tgid_array[i]; 2189 ino_t ino = fake_ino(tgid,PROC_TGID_INO); 2190 unsigned long j = PROC_NUMBUF; 2191 2192 do 2193 buf[--j] = '0' + (tgid % 10); 2194 while ((tgid /= 10) != 0); 2195 2196 if (filldir(dirent, buf+j, PROC_NUMBUF-j, filp->f_pos, ino, DT_DIR) < 0) { 2197 /* returning this tgid failed, save it as the first 2198 * pid for the next readir call */ 2199 filp->f_version = tgid_array[i]; 2200 goto out; 2201 } 2202 filp->f_pos++; 2203 nr++; 2204 } 2205 } 2206 out: 2207 return 0; 2208 } 2209 2210 /* for the /proc/TGID/task/ directories */ 2211 static int proc_task_readdir(struct file * filp, void * dirent, filldir_t filldir) 2212 { 2213 unsigned int tid_array[PROC_MAXPIDS]; 2214 char buf[PROC_NUMBUF]; 2215 unsigned int nr_tids, i; 2216 struct dentry *dentry = filp->f_dentry; 2217 struct inode *inode = dentry->d_inode; 2218 int retval = -ENOENT; 2219 ino_t ino; 2220 unsigned long pos = filp->f_pos; /* avoiding "long long" filp->f_pos */ 2221 2222 if (!pid_alive(proc_task(inode))) 2223 goto out; 2224 retval = 0; 2225 2226 switch (pos) { 2227 case 0: 2228 ino = inode->i_ino; 2229 if (filldir(dirent, ".", 1, pos, ino, DT_DIR) < 0) 2230 goto out; 2231 pos++; 2232 /* fall through */ 2233 case 1: 2234 ino = parent_ino(dentry); 2235 if (filldir(dirent, "..", 2, pos, ino, DT_DIR) < 0) 2236 goto out; 2237 pos++; 2238 /* fall through */ 2239 } 2240 2241 nr_tids = get_tid_list(pos, tid_array, inode); 2242 inode->i_nlink = pos + nr_tids; 2243 2244 for (i = 0; i < nr_tids; i++) { 2245 unsigned long j = PROC_NUMBUF; 2246 int tid = tid_array[i]; 2247 2248 ino = fake_ino(tid,PROC_TID_INO); 2249 2250 do 2251 buf[--j] = '0' + (tid % 10); 2252 while ((tid /= 10) != 0); 2253 2254 if (filldir(dirent, buf+j, PROC_NUMBUF-j, pos, ino, DT_DIR) < 0) 2255 break; 2256 pos++; 2257 } 2258 out: 2259 filp->f_pos = pos; 2260 return retval; 2261 } 2262