1 /* 2 * sysctl.c: General linux system control interface 3 * 4 * Begun 24 March 1995, Stephen Tweedie 5 * Added /proc support, Dec 1995 6 * Added bdflush entry and intvec min/max checking, 2/23/96, Tom Dyas. 7 * Added hooks for /proc/sys/net (minor, minor patch), 96/4/1, Mike Shaver. 8 * Added kernel/java-{interpreter,appletviewer}, 96/5/10, Mike Shaver. 9 * Dynamic registration fixes, Stephen Tweedie. 10 * Added kswapd-interval, ctrl-alt-del, printk stuff, 1/8/97, Chris Horn. 11 * Made sysctl support optional via CONFIG_SYSCTL, 1/10/97, Chris 12 * Horn. 13 * Added proc_doulongvec_ms_jiffies_minmax, 09/08/99, Carlos H. Bauer. 14 * Added proc_doulongvec_minmax, 09/08/99, Carlos H. Bauer. 15 * Changed linked lists to use list.h instead of lists.h, 02/24/00, Bill 16 * Wendling. 17 * The list_for_each() macro wasn't appropriate for the sysctl loop. 18 * Removed it and replaced it with older style, 03/23/00, Bill Wendling 19 */ 20 21 #include <linux/config.h> 22 #include <linux/module.h> 23 #include <linux/mm.h> 24 #include <linux/swap.h> 25 #include <linux/slab.h> 26 #include <linux/sysctl.h> 27 #include <linux/proc_fs.h> 28 #include <linux/ctype.h> 29 #include <linux/utsname.h> 30 #include <linux/capability.h> 31 #include <linux/smp_lock.h> 32 #include <linux/init.h> 33 #include <linux/kernel.h> 34 #include <linux/kobject.h> 35 #include <linux/net.h> 36 #include <linux/sysrq.h> 37 #include <linux/highuid.h> 38 #include <linux/writeback.h> 39 #include <linux/hugetlb.h> 40 #include <linux/security.h> 41 #include <linux/initrd.h> 42 #include <linux/times.h> 43 #include <linux/limits.h> 44 #include <linux/dcache.h> 45 #include <linux/syscalls.h> 46 47 #include <asm/uaccess.h> 48 #include <asm/processor.h> 49 50 #ifdef CONFIG_ROOT_NFS 51 #include <linux/nfs_fs.h> 52 #endif 53 54 #if defined(CONFIG_SYSCTL) 55 56 /* External variables not in a header file. */ 57 extern int C_A_D; 58 extern int sysctl_overcommit_memory; 59 extern int sysctl_overcommit_ratio; 60 extern int max_threads; 61 extern int sysrq_enabled; 62 extern int core_uses_pid; 63 extern int suid_dumpable; 64 extern char core_pattern[]; 65 extern int cad_pid; 66 extern int pid_max; 67 extern int min_free_kbytes; 68 extern int printk_ratelimit_jiffies; 69 extern int printk_ratelimit_burst; 70 extern int pid_max_min, pid_max_max; 71 extern int sysctl_drop_caches; 72 extern int percpu_pagelist_fraction; 73 74 #if defined(CONFIG_X86_LOCAL_APIC) && defined(CONFIG_X86) 75 int unknown_nmi_panic; 76 extern int proc_unknown_nmi_panic(ctl_table *, int, struct file *, 77 void __user *, size_t *, loff_t *); 78 #endif 79 80 /* this is needed for the proc_dointvec_minmax for [fs_]overflow UID and GID */ 81 static int maxolduid = 65535; 82 static int minolduid; 83 static int min_percpu_pagelist_fract = 8; 84 85 static int ngroups_max = NGROUPS_MAX; 86 87 #ifdef CONFIG_KMOD 88 extern char modprobe_path[]; 89 #endif 90 #ifdef CONFIG_CHR_DEV_SG 91 extern int sg_big_buff; 92 #endif 93 #ifdef CONFIG_SYSVIPC 94 extern size_t shm_ctlmax; 95 extern size_t shm_ctlall; 96 extern int shm_ctlmni; 97 extern int msg_ctlmax; 98 extern int msg_ctlmnb; 99 extern int msg_ctlmni; 100 extern int sem_ctls[]; 101 #endif 102 103 #ifdef __sparc__ 104 extern char reboot_command []; 105 extern int stop_a_enabled; 106 extern int scons_pwroff; 107 #endif 108 109 #ifdef __hppa__ 110 extern int pwrsw_enabled; 111 extern int unaligned_enabled; 112 #endif 113 114 #ifdef CONFIG_S390 115 #ifdef CONFIG_MATHEMU 116 extern int sysctl_ieee_emulation_warnings; 117 #endif 118 extern int sysctl_userprocess_debug; 119 extern int spin_retry; 120 #endif 121 122 extern int sysctl_hz_timer; 123 124 #ifdef CONFIG_BSD_PROCESS_ACCT 125 extern int acct_parm[]; 126 #endif 127 128 int randomize_va_space = 1; 129 130 static int parse_table(int __user *, int, void __user *, size_t __user *, void __user *, size_t, 131 ctl_table *, void **); 132 static int proc_doutsstring(ctl_table *table, int write, struct file *filp, 133 void __user *buffer, size_t *lenp, loff_t *ppos); 134 135 static ctl_table root_table[]; 136 static struct ctl_table_header root_table_header = 137 { root_table, LIST_HEAD_INIT(root_table_header.ctl_entry) }; 138 139 static ctl_table kern_table[]; 140 static ctl_table vm_table[]; 141 static ctl_table proc_table[]; 142 static ctl_table fs_table[]; 143 static ctl_table debug_table[]; 144 static ctl_table dev_table[]; 145 extern ctl_table random_table[]; 146 #ifdef CONFIG_UNIX98_PTYS 147 extern ctl_table pty_table[]; 148 #endif 149 #ifdef CONFIG_INOTIFY 150 extern ctl_table inotify_table[]; 151 #endif 152 153 #ifdef HAVE_ARCH_PICK_MMAP_LAYOUT 154 int sysctl_legacy_va_layout; 155 #endif 156 157 /* /proc declarations: */ 158 159 #ifdef CONFIG_PROC_FS 160 161 static ssize_t proc_readsys(struct file *, char __user *, size_t, loff_t *); 162 static ssize_t proc_writesys(struct file *, const char __user *, size_t, loff_t *); 163 static int proc_opensys(struct inode *, struct file *); 164 165 struct file_operations proc_sys_file_operations = { 166 .open = proc_opensys, 167 .read = proc_readsys, 168 .write = proc_writesys, 169 }; 170 171 extern struct proc_dir_entry *proc_sys_root; 172 173 static void register_proc_table(ctl_table *, struct proc_dir_entry *, void *); 174 static void unregister_proc_table(ctl_table *, struct proc_dir_entry *); 175 #endif 176 177 /* The default sysctl tables: */ 178 179 static ctl_table root_table[] = { 180 { 181 .ctl_name = CTL_KERN, 182 .procname = "kernel", 183 .mode = 0555, 184 .child = kern_table, 185 }, 186 { 187 .ctl_name = CTL_VM, 188 .procname = "vm", 189 .mode = 0555, 190 .child = vm_table, 191 }, 192 #ifdef CONFIG_NET 193 { 194 .ctl_name = CTL_NET, 195 .procname = "net", 196 .mode = 0555, 197 .child = net_table, 198 }, 199 #endif 200 { 201 .ctl_name = CTL_PROC, 202 .procname = "proc", 203 .mode = 0555, 204 .child = proc_table, 205 }, 206 { 207 .ctl_name = CTL_FS, 208 .procname = "fs", 209 .mode = 0555, 210 .child = fs_table, 211 }, 212 { 213 .ctl_name = CTL_DEBUG, 214 .procname = "debug", 215 .mode = 0555, 216 .child = debug_table, 217 }, 218 { 219 .ctl_name = CTL_DEV, 220 .procname = "dev", 221 .mode = 0555, 222 .child = dev_table, 223 }, 224 225 { .ctl_name = 0 } 226 }; 227 228 static ctl_table kern_table[] = { 229 { 230 .ctl_name = KERN_OSTYPE, 231 .procname = "ostype", 232 .data = system_utsname.sysname, 233 .maxlen = sizeof(system_utsname.sysname), 234 .mode = 0444, 235 .proc_handler = &proc_doutsstring, 236 .strategy = &sysctl_string, 237 }, 238 { 239 .ctl_name = KERN_OSRELEASE, 240 .procname = "osrelease", 241 .data = system_utsname.release, 242 .maxlen = sizeof(system_utsname.release), 243 .mode = 0444, 244 .proc_handler = &proc_doutsstring, 245 .strategy = &sysctl_string, 246 }, 247 { 248 .ctl_name = KERN_VERSION, 249 .procname = "version", 250 .data = system_utsname.version, 251 .maxlen = sizeof(system_utsname.version), 252 .mode = 0444, 253 .proc_handler = &proc_doutsstring, 254 .strategy = &sysctl_string, 255 }, 256 { 257 .ctl_name = KERN_NODENAME, 258 .procname = "hostname", 259 .data = system_utsname.nodename, 260 .maxlen = sizeof(system_utsname.nodename), 261 .mode = 0644, 262 .proc_handler = &proc_doutsstring, 263 .strategy = &sysctl_string, 264 }, 265 { 266 .ctl_name = KERN_DOMAINNAME, 267 .procname = "domainname", 268 .data = system_utsname.domainname, 269 .maxlen = sizeof(system_utsname.domainname), 270 .mode = 0644, 271 .proc_handler = &proc_doutsstring, 272 .strategy = &sysctl_string, 273 }, 274 { 275 .ctl_name = KERN_PANIC, 276 .procname = "panic", 277 .data = &panic_timeout, 278 .maxlen = sizeof(int), 279 .mode = 0644, 280 .proc_handler = &proc_dointvec, 281 }, 282 { 283 .ctl_name = KERN_CORE_USES_PID, 284 .procname = "core_uses_pid", 285 .data = &core_uses_pid, 286 .maxlen = sizeof(int), 287 .mode = 0644, 288 .proc_handler = &proc_dointvec, 289 }, 290 { 291 .ctl_name = KERN_CORE_PATTERN, 292 .procname = "core_pattern", 293 .data = core_pattern, 294 .maxlen = 64, 295 .mode = 0644, 296 .proc_handler = &proc_dostring, 297 .strategy = &sysctl_string, 298 }, 299 { 300 .ctl_name = KERN_TAINTED, 301 .procname = "tainted", 302 .data = &tainted, 303 .maxlen = sizeof(int), 304 .mode = 0444, 305 .proc_handler = &proc_dointvec, 306 }, 307 { 308 .ctl_name = KERN_CAP_BSET, 309 .procname = "cap-bound", 310 .data = &cap_bset, 311 .maxlen = sizeof(kernel_cap_t), 312 .mode = 0600, 313 .proc_handler = &proc_dointvec_bset, 314 }, 315 #ifdef CONFIG_BLK_DEV_INITRD 316 { 317 .ctl_name = KERN_REALROOTDEV, 318 .procname = "real-root-dev", 319 .data = &real_root_dev, 320 .maxlen = sizeof(int), 321 .mode = 0644, 322 .proc_handler = &proc_dointvec, 323 }, 324 #endif 325 #ifdef __sparc__ 326 { 327 .ctl_name = KERN_SPARC_REBOOT, 328 .procname = "reboot-cmd", 329 .data = reboot_command, 330 .maxlen = 256, 331 .mode = 0644, 332 .proc_handler = &proc_dostring, 333 .strategy = &sysctl_string, 334 }, 335 { 336 .ctl_name = KERN_SPARC_STOP_A, 337 .procname = "stop-a", 338 .data = &stop_a_enabled, 339 .maxlen = sizeof (int), 340 .mode = 0644, 341 .proc_handler = &proc_dointvec, 342 }, 343 { 344 .ctl_name = KERN_SPARC_SCONS_PWROFF, 345 .procname = "scons-poweroff", 346 .data = &scons_pwroff, 347 .maxlen = sizeof (int), 348 .mode = 0644, 349 .proc_handler = &proc_dointvec, 350 }, 351 #endif 352 #ifdef __hppa__ 353 { 354 .ctl_name = KERN_HPPA_PWRSW, 355 .procname = "soft-power", 356 .data = &pwrsw_enabled, 357 .maxlen = sizeof (int), 358 .mode = 0644, 359 .proc_handler = &proc_dointvec, 360 }, 361 { 362 .ctl_name = KERN_HPPA_UNALIGNED, 363 .procname = "unaligned-trap", 364 .data = &unaligned_enabled, 365 .maxlen = sizeof (int), 366 .mode = 0644, 367 .proc_handler = &proc_dointvec, 368 }, 369 #endif 370 { 371 .ctl_name = KERN_CTLALTDEL, 372 .procname = "ctrl-alt-del", 373 .data = &C_A_D, 374 .maxlen = sizeof(int), 375 .mode = 0644, 376 .proc_handler = &proc_dointvec, 377 }, 378 { 379 .ctl_name = KERN_PRINTK, 380 .procname = "printk", 381 .data = &console_loglevel, 382 .maxlen = 4*sizeof(int), 383 .mode = 0644, 384 .proc_handler = &proc_dointvec, 385 }, 386 #ifdef CONFIG_KMOD 387 { 388 .ctl_name = KERN_MODPROBE, 389 .procname = "modprobe", 390 .data = &modprobe_path, 391 .maxlen = KMOD_PATH_LEN, 392 .mode = 0644, 393 .proc_handler = &proc_dostring, 394 .strategy = &sysctl_string, 395 }, 396 #endif 397 #ifdef CONFIG_HOTPLUG 398 { 399 .ctl_name = KERN_HOTPLUG, 400 .procname = "hotplug", 401 .data = &uevent_helper, 402 .maxlen = UEVENT_HELPER_PATH_LEN, 403 .mode = 0644, 404 .proc_handler = &proc_dostring, 405 .strategy = &sysctl_string, 406 }, 407 #endif 408 #ifdef CONFIG_CHR_DEV_SG 409 { 410 .ctl_name = KERN_SG_BIG_BUFF, 411 .procname = "sg-big-buff", 412 .data = &sg_big_buff, 413 .maxlen = sizeof (int), 414 .mode = 0444, 415 .proc_handler = &proc_dointvec, 416 }, 417 #endif 418 #ifdef CONFIG_BSD_PROCESS_ACCT 419 { 420 .ctl_name = KERN_ACCT, 421 .procname = "acct", 422 .data = &acct_parm, 423 .maxlen = 3*sizeof(int), 424 .mode = 0644, 425 .proc_handler = &proc_dointvec, 426 }, 427 #endif 428 #ifdef CONFIG_SYSVIPC 429 { 430 .ctl_name = KERN_SHMMAX, 431 .procname = "shmmax", 432 .data = &shm_ctlmax, 433 .maxlen = sizeof (size_t), 434 .mode = 0644, 435 .proc_handler = &proc_doulongvec_minmax, 436 }, 437 { 438 .ctl_name = KERN_SHMALL, 439 .procname = "shmall", 440 .data = &shm_ctlall, 441 .maxlen = sizeof (size_t), 442 .mode = 0644, 443 .proc_handler = &proc_doulongvec_minmax, 444 }, 445 { 446 .ctl_name = KERN_SHMMNI, 447 .procname = "shmmni", 448 .data = &shm_ctlmni, 449 .maxlen = sizeof (int), 450 .mode = 0644, 451 .proc_handler = &proc_dointvec, 452 }, 453 { 454 .ctl_name = KERN_MSGMAX, 455 .procname = "msgmax", 456 .data = &msg_ctlmax, 457 .maxlen = sizeof (int), 458 .mode = 0644, 459 .proc_handler = &proc_dointvec, 460 }, 461 { 462 .ctl_name = KERN_MSGMNI, 463 .procname = "msgmni", 464 .data = &msg_ctlmni, 465 .maxlen = sizeof (int), 466 .mode = 0644, 467 .proc_handler = &proc_dointvec, 468 }, 469 { 470 .ctl_name = KERN_MSGMNB, 471 .procname = "msgmnb", 472 .data = &msg_ctlmnb, 473 .maxlen = sizeof (int), 474 .mode = 0644, 475 .proc_handler = &proc_dointvec, 476 }, 477 { 478 .ctl_name = KERN_SEM, 479 .procname = "sem", 480 .data = &sem_ctls, 481 .maxlen = 4*sizeof (int), 482 .mode = 0644, 483 .proc_handler = &proc_dointvec, 484 }, 485 #endif 486 #ifdef CONFIG_MAGIC_SYSRQ 487 { 488 .ctl_name = KERN_SYSRQ, 489 .procname = "sysrq", 490 .data = &sysrq_enabled, 491 .maxlen = sizeof (int), 492 .mode = 0644, 493 .proc_handler = &proc_dointvec, 494 }, 495 #endif 496 { 497 .ctl_name = KERN_CADPID, 498 .procname = "cad_pid", 499 .data = &cad_pid, 500 .maxlen = sizeof (int), 501 .mode = 0600, 502 .proc_handler = &proc_dointvec, 503 }, 504 { 505 .ctl_name = KERN_MAX_THREADS, 506 .procname = "threads-max", 507 .data = &max_threads, 508 .maxlen = sizeof(int), 509 .mode = 0644, 510 .proc_handler = &proc_dointvec, 511 }, 512 { 513 .ctl_name = KERN_RANDOM, 514 .procname = "random", 515 .mode = 0555, 516 .child = random_table, 517 }, 518 #ifdef CONFIG_UNIX98_PTYS 519 { 520 .ctl_name = KERN_PTY, 521 .procname = "pty", 522 .mode = 0555, 523 .child = pty_table, 524 }, 525 #endif 526 { 527 .ctl_name = KERN_OVERFLOWUID, 528 .procname = "overflowuid", 529 .data = &overflowuid, 530 .maxlen = sizeof(int), 531 .mode = 0644, 532 .proc_handler = &proc_dointvec_minmax, 533 .strategy = &sysctl_intvec, 534 .extra1 = &minolduid, 535 .extra2 = &maxolduid, 536 }, 537 { 538 .ctl_name = KERN_OVERFLOWGID, 539 .procname = "overflowgid", 540 .data = &overflowgid, 541 .maxlen = sizeof(int), 542 .mode = 0644, 543 .proc_handler = &proc_dointvec_minmax, 544 .strategy = &sysctl_intvec, 545 .extra1 = &minolduid, 546 .extra2 = &maxolduid, 547 }, 548 #ifdef CONFIG_S390 549 #ifdef CONFIG_MATHEMU 550 { 551 .ctl_name = KERN_IEEE_EMULATION_WARNINGS, 552 .procname = "ieee_emulation_warnings", 553 .data = &sysctl_ieee_emulation_warnings, 554 .maxlen = sizeof(int), 555 .mode = 0644, 556 .proc_handler = &proc_dointvec, 557 }, 558 #endif 559 #ifdef CONFIG_NO_IDLE_HZ 560 { 561 .ctl_name = KERN_HZ_TIMER, 562 .procname = "hz_timer", 563 .data = &sysctl_hz_timer, 564 .maxlen = sizeof(int), 565 .mode = 0644, 566 .proc_handler = &proc_dointvec, 567 }, 568 #endif 569 { 570 .ctl_name = KERN_S390_USER_DEBUG_LOGGING, 571 .procname = "userprocess_debug", 572 .data = &sysctl_userprocess_debug, 573 .maxlen = sizeof(int), 574 .mode = 0644, 575 .proc_handler = &proc_dointvec, 576 }, 577 #endif 578 { 579 .ctl_name = KERN_PIDMAX, 580 .procname = "pid_max", 581 .data = &pid_max, 582 .maxlen = sizeof (int), 583 .mode = 0644, 584 .proc_handler = &proc_dointvec_minmax, 585 .strategy = sysctl_intvec, 586 .extra1 = &pid_max_min, 587 .extra2 = &pid_max_max, 588 }, 589 { 590 .ctl_name = KERN_PANIC_ON_OOPS, 591 .procname = "panic_on_oops", 592 .data = &panic_on_oops, 593 .maxlen = sizeof(int), 594 .mode = 0644, 595 .proc_handler = &proc_dointvec, 596 }, 597 { 598 .ctl_name = KERN_PRINTK_RATELIMIT, 599 .procname = "printk_ratelimit", 600 .data = &printk_ratelimit_jiffies, 601 .maxlen = sizeof(int), 602 .mode = 0644, 603 .proc_handler = &proc_dointvec_jiffies, 604 .strategy = &sysctl_jiffies, 605 }, 606 { 607 .ctl_name = KERN_PRINTK_RATELIMIT_BURST, 608 .procname = "printk_ratelimit_burst", 609 .data = &printk_ratelimit_burst, 610 .maxlen = sizeof(int), 611 .mode = 0644, 612 .proc_handler = &proc_dointvec, 613 }, 614 { 615 .ctl_name = KERN_NGROUPS_MAX, 616 .procname = "ngroups_max", 617 .data = &ngroups_max, 618 .maxlen = sizeof (int), 619 .mode = 0444, 620 .proc_handler = &proc_dointvec, 621 }, 622 #if defined(CONFIG_X86_LOCAL_APIC) && defined(CONFIG_X86) 623 { 624 .ctl_name = KERN_UNKNOWN_NMI_PANIC, 625 .procname = "unknown_nmi_panic", 626 .data = &unknown_nmi_panic, 627 .maxlen = sizeof (int), 628 .mode = 0644, 629 .proc_handler = &proc_unknown_nmi_panic, 630 }, 631 #endif 632 #if defined(CONFIG_X86) 633 { 634 .ctl_name = KERN_BOOTLOADER_TYPE, 635 .procname = "bootloader_type", 636 .data = &bootloader_type, 637 .maxlen = sizeof (int), 638 .mode = 0444, 639 .proc_handler = &proc_dointvec, 640 }, 641 #endif 642 { 643 .ctl_name = KERN_RANDOMIZE, 644 .procname = "randomize_va_space", 645 .data = &randomize_va_space, 646 .maxlen = sizeof(int), 647 .mode = 0644, 648 .proc_handler = &proc_dointvec, 649 }, 650 #if defined(CONFIG_S390) 651 { 652 .ctl_name = KERN_SPIN_RETRY, 653 .procname = "spin_retry", 654 .data = &spin_retry, 655 .maxlen = sizeof (int), 656 .mode = 0644, 657 .proc_handler = &proc_dointvec, 658 }, 659 #endif 660 { .ctl_name = 0 } 661 }; 662 663 /* Constants for minimum and maximum testing in vm_table. 664 We use these as one-element integer vectors. */ 665 static int zero; 666 static int one_hundred = 100; 667 668 669 static ctl_table vm_table[] = { 670 { 671 .ctl_name = VM_OVERCOMMIT_MEMORY, 672 .procname = "overcommit_memory", 673 .data = &sysctl_overcommit_memory, 674 .maxlen = sizeof(sysctl_overcommit_memory), 675 .mode = 0644, 676 .proc_handler = &proc_dointvec, 677 }, 678 { 679 .ctl_name = VM_OVERCOMMIT_RATIO, 680 .procname = "overcommit_ratio", 681 .data = &sysctl_overcommit_ratio, 682 .maxlen = sizeof(sysctl_overcommit_ratio), 683 .mode = 0644, 684 .proc_handler = &proc_dointvec, 685 }, 686 { 687 .ctl_name = VM_PAGE_CLUSTER, 688 .procname = "page-cluster", 689 .data = &page_cluster, 690 .maxlen = sizeof(int), 691 .mode = 0644, 692 .proc_handler = &proc_dointvec, 693 }, 694 { 695 .ctl_name = VM_DIRTY_BACKGROUND, 696 .procname = "dirty_background_ratio", 697 .data = &dirty_background_ratio, 698 .maxlen = sizeof(dirty_background_ratio), 699 .mode = 0644, 700 .proc_handler = &proc_dointvec_minmax, 701 .strategy = &sysctl_intvec, 702 .extra1 = &zero, 703 .extra2 = &one_hundred, 704 }, 705 { 706 .ctl_name = VM_DIRTY_RATIO, 707 .procname = "dirty_ratio", 708 .data = &vm_dirty_ratio, 709 .maxlen = sizeof(vm_dirty_ratio), 710 .mode = 0644, 711 .proc_handler = &proc_dointvec_minmax, 712 .strategy = &sysctl_intvec, 713 .extra1 = &zero, 714 .extra2 = &one_hundred, 715 }, 716 { 717 .ctl_name = VM_DIRTY_WB_CS, 718 .procname = "dirty_writeback_centisecs", 719 .data = &dirty_writeback_centisecs, 720 .maxlen = sizeof(dirty_writeback_centisecs), 721 .mode = 0644, 722 .proc_handler = &dirty_writeback_centisecs_handler, 723 }, 724 { 725 .ctl_name = VM_DIRTY_EXPIRE_CS, 726 .procname = "dirty_expire_centisecs", 727 .data = &dirty_expire_centisecs, 728 .maxlen = sizeof(dirty_expire_centisecs), 729 .mode = 0644, 730 .proc_handler = &proc_dointvec, 731 }, 732 { 733 .ctl_name = VM_NR_PDFLUSH_THREADS, 734 .procname = "nr_pdflush_threads", 735 .data = &nr_pdflush_threads, 736 .maxlen = sizeof nr_pdflush_threads, 737 .mode = 0444 /* read-only*/, 738 .proc_handler = &proc_dointvec, 739 }, 740 { 741 .ctl_name = VM_SWAPPINESS, 742 .procname = "swappiness", 743 .data = &vm_swappiness, 744 .maxlen = sizeof(vm_swappiness), 745 .mode = 0644, 746 .proc_handler = &proc_dointvec_minmax, 747 .strategy = &sysctl_intvec, 748 .extra1 = &zero, 749 .extra2 = &one_hundred, 750 }, 751 #ifdef CONFIG_HUGETLB_PAGE 752 { 753 .ctl_name = VM_HUGETLB_PAGES, 754 .procname = "nr_hugepages", 755 .data = &max_huge_pages, 756 .maxlen = sizeof(unsigned long), 757 .mode = 0644, 758 .proc_handler = &hugetlb_sysctl_handler, 759 .extra1 = (void *)&hugetlb_zero, 760 .extra2 = (void *)&hugetlb_infinity, 761 }, 762 { 763 .ctl_name = VM_HUGETLB_GROUP, 764 .procname = "hugetlb_shm_group", 765 .data = &sysctl_hugetlb_shm_group, 766 .maxlen = sizeof(gid_t), 767 .mode = 0644, 768 .proc_handler = &proc_dointvec, 769 }, 770 #endif 771 { 772 .ctl_name = VM_LOWMEM_RESERVE_RATIO, 773 .procname = "lowmem_reserve_ratio", 774 .data = &sysctl_lowmem_reserve_ratio, 775 .maxlen = sizeof(sysctl_lowmem_reserve_ratio), 776 .mode = 0644, 777 .proc_handler = &lowmem_reserve_ratio_sysctl_handler, 778 .strategy = &sysctl_intvec, 779 }, 780 { 781 .ctl_name = VM_DROP_PAGECACHE, 782 .procname = "drop_caches", 783 .data = &sysctl_drop_caches, 784 .maxlen = sizeof(int), 785 .mode = 0644, 786 .proc_handler = drop_caches_sysctl_handler, 787 .strategy = &sysctl_intvec, 788 }, 789 { 790 .ctl_name = VM_MIN_FREE_KBYTES, 791 .procname = "min_free_kbytes", 792 .data = &min_free_kbytes, 793 .maxlen = sizeof(min_free_kbytes), 794 .mode = 0644, 795 .proc_handler = &min_free_kbytes_sysctl_handler, 796 .strategy = &sysctl_intvec, 797 .extra1 = &zero, 798 }, 799 { 800 .ctl_name = VM_PERCPU_PAGELIST_FRACTION, 801 .procname = "percpu_pagelist_fraction", 802 .data = &percpu_pagelist_fraction, 803 .maxlen = sizeof(percpu_pagelist_fraction), 804 .mode = 0644, 805 .proc_handler = &percpu_pagelist_fraction_sysctl_handler, 806 .strategy = &sysctl_intvec, 807 .extra1 = &min_percpu_pagelist_fract, 808 }, 809 #ifdef CONFIG_MMU 810 { 811 .ctl_name = VM_MAX_MAP_COUNT, 812 .procname = "max_map_count", 813 .data = &sysctl_max_map_count, 814 .maxlen = sizeof(sysctl_max_map_count), 815 .mode = 0644, 816 .proc_handler = &proc_dointvec 817 }, 818 #endif 819 { 820 .ctl_name = VM_LAPTOP_MODE, 821 .procname = "laptop_mode", 822 .data = &laptop_mode, 823 .maxlen = sizeof(laptop_mode), 824 .mode = 0644, 825 .proc_handler = &proc_dointvec, 826 .strategy = &sysctl_intvec, 827 .extra1 = &zero, 828 }, 829 { 830 .ctl_name = VM_BLOCK_DUMP, 831 .procname = "block_dump", 832 .data = &block_dump, 833 .maxlen = sizeof(block_dump), 834 .mode = 0644, 835 .proc_handler = &proc_dointvec, 836 .strategy = &sysctl_intvec, 837 .extra1 = &zero, 838 }, 839 { 840 .ctl_name = VM_VFS_CACHE_PRESSURE, 841 .procname = "vfs_cache_pressure", 842 .data = &sysctl_vfs_cache_pressure, 843 .maxlen = sizeof(sysctl_vfs_cache_pressure), 844 .mode = 0644, 845 .proc_handler = &proc_dointvec, 846 .strategy = &sysctl_intvec, 847 .extra1 = &zero, 848 }, 849 #ifdef HAVE_ARCH_PICK_MMAP_LAYOUT 850 { 851 .ctl_name = VM_LEGACY_VA_LAYOUT, 852 .procname = "legacy_va_layout", 853 .data = &sysctl_legacy_va_layout, 854 .maxlen = sizeof(sysctl_legacy_va_layout), 855 .mode = 0644, 856 .proc_handler = &proc_dointvec, 857 .strategy = &sysctl_intvec, 858 .extra1 = &zero, 859 }, 860 #endif 861 #ifdef CONFIG_SWAP 862 { 863 .ctl_name = VM_SWAP_TOKEN_TIMEOUT, 864 .procname = "swap_token_timeout", 865 .data = &swap_token_default_timeout, 866 .maxlen = sizeof(swap_token_default_timeout), 867 .mode = 0644, 868 .proc_handler = &proc_dointvec_jiffies, 869 .strategy = &sysctl_jiffies, 870 }, 871 #endif 872 { .ctl_name = 0 } 873 }; 874 875 static ctl_table proc_table[] = { 876 { .ctl_name = 0 } 877 }; 878 879 static ctl_table fs_table[] = { 880 { 881 .ctl_name = FS_NRINODE, 882 .procname = "inode-nr", 883 .data = &inodes_stat, 884 .maxlen = 2*sizeof(int), 885 .mode = 0444, 886 .proc_handler = &proc_dointvec, 887 }, 888 { 889 .ctl_name = FS_STATINODE, 890 .procname = "inode-state", 891 .data = &inodes_stat, 892 .maxlen = 7*sizeof(int), 893 .mode = 0444, 894 .proc_handler = &proc_dointvec, 895 }, 896 { 897 .ctl_name = FS_NRFILE, 898 .procname = "file-nr", 899 .data = &files_stat, 900 .maxlen = 3*sizeof(int), 901 .mode = 0444, 902 .proc_handler = &proc_dointvec, 903 }, 904 { 905 .ctl_name = FS_MAXFILE, 906 .procname = "file-max", 907 .data = &files_stat.max_files, 908 .maxlen = sizeof(int), 909 .mode = 0644, 910 .proc_handler = &proc_dointvec, 911 }, 912 { 913 .ctl_name = FS_DENTRY, 914 .procname = "dentry-state", 915 .data = &dentry_stat, 916 .maxlen = 6*sizeof(int), 917 .mode = 0444, 918 .proc_handler = &proc_dointvec, 919 }, 920 { 921 .ctl_name = FS_OVERFLOWUID, 922 .procname = "overflowuid", 923 .data = &fs_overflowuid, 924 .maxlen = sizeof(int), 925 .mode = 0644, 926 .proc_handler = &proc_dointvec_minmax, 927 .strategy = &sysctl_intvec, 928 .extra1 = &minolduid, 929 .extra2 = &maxolduid, 930 }, 931 { 932 .ctl_name = FS_OVERFLOWGID, 933 .procname = "overflowgid", 934 .data = &fs_overflowgid, 935 .maxlen = sizeof(int), 936 .mode = 0644, 937 .proc_handler = &proc_dointvec_minmax, 938 .strategy = &sysctl_intvec, 939 .extra1 = &minolduid, 940 .extra2 = &maxolduid, 941 }, 942 { 943 .ctl_name = FS_LEASES, 944 .procname = "leases-enable", 945 .data = &leases_enable, 946 .maxlen = sizeof(int), 947 .mode = 0644, 948 .proc_handler = &proc_dointvec, 949 }, 950 #ifdef CONFIG_DNOTIFY 951 { 952 .ctl_name = FS_DIR_NOTIFY, 953 .procname = "dir-notify-enable", 954 .data = &dir_notify_enable, 955 .maxlen = sizeof(int), 956 .mode = 0644, 957 .proc_handler = &proc_dointvec, 958 }, 959 #endif 960 #ifdef CONFIG_MMU 961 { 962 .ctl_name = FS_LEASE_TIME, 963 .procname = "lease-break-time", 964 .data = &lease_break_time, 965 .maxlen = sizeof(int), 966 .mode = 0644, 967 .proc_handler = &proc_dointvec, 968 }, 969 { 970 .ctl_name = FS_AIO_NR, 971 .procname = "aio-nr", 972 .data = &aio_nr, 973 .maxlen = sizeof(aio_nr), 974 .mode = 0444, 975 .proc_handler = &proc_doulongvec_minmax, 976 }, 977 { 978 .ctl_name = FS_AIO_MAX_NR, 979 .procname = "aio-max-nr", 980 .data = &aio_max_nr, 981 .maxlen = sizeof(aio_max_nr), 982 .mode = 0644, 983 .proc_handler = &proc_doulongvec_minmax, 984 }, 985 #ifdef CONFIG_INOTIFY 986 { 987 .ctl_name = FS_INOTIFY, 988 .procname = "inotify", 989 .mode = 0555, 990 .child = inotify_table, 991 }, 992 #endif 993 #endif 994 { 995 .ctl_name = KERN_SETUID_DUMPABLE, 996 .procname = "suid_dumpable", 997 .data = &suid_dumpable, 998 .maxlen = sizeof(int), 999 .mode = 0644, 1000 .proc_handler = &proc_dointvec, 1001 }, 1002 { .ctl_name = 0 } 1003 }; 1004 1005 static ctl_table debug_table[] = { 1006 { .ctl_name = 0 } 1007 }; 1008 1009 static ctl_table dev_table[] = { 1010 { .ctl_name = 0 } 1011 }; 1012 1013 extern void init_irq_proc (void); 1014 1015 static DEFINE_SPINLOCK(sysctl_lock); 1016 1017 /* called under sysctl_lock */ 1018 static int use_table(struct ctl_table_header *p) 1019 { 1020 if (unlikely(p->unregistering)) 1021 return 0; 1022 p->used++; 1023 return 1; 1024 } 1025 1026 /* called under sysctl_lock */ 1027 static void unuse_table(struct ctl_table_header *p) 1028 { 1029 if (!--p->used) 1030 if (unlikely(p->unregistering)) 1031 complete(p->unregistering); 1032 } 1033 1034 /* called under sysctl_lock, will reacquire if has to wait */ 1035 static void start_unregistering(struct ctl_table_header *p) 1036 { 1037 /* 1038 * if p->used is 0, nobody will ever touch that entry again; 1039 * we'll eliminate all paths to it before dropping sysctl_lock 1040 */ 1041 if (unlikely(p->used)) { 1042 struct completion wait; 1043 init_completion(&wait); 1044 p->unregistering = &wait; 1045 spin_unlock(&sysctl_lock); 1046 wait_for_completion(&wait); 1047 spin_lock(&sysctl_lock); 1048 } 1049 /* 1050 * do not remove from the list until nobody holds it; walking the 1051 * list in do_sysctl() relies on that. 1052 */ 1053 list_del_init(&p->ctl_entry); 1054 } 1055 1056 void __init sysctl_init(void) 1057 { 1058 #ifdef CONFIG_PROC_FS 1059 register_proc_table(root_table, proc_sys_root, &root_table_header); 1060 init_irq_proc(); 1061 #endif 1062 } 1063 1064 int do_sysctl(int __user *name, int nlen, void __user *oldval, size_t __user *oldlenp, 1065 void __user *newval, size_t newlen) 1066 { 1067 struct list_head *tmp; 1068 int error = -ENOTDIR; 1069 1070 if (nlen <= 0 || nlen >= CTL_MAXNAME) 1071 return -ENOTDIR; 1072 if (oldval) { 1073 int old_len; 1074 if (!oldlenp || get_user(old_len, oldlenp)) 1075 return -EFAULT; 1076 } 1077 spin_lock(&sysctl_lock); 1078 tmp = &root_table_header.ctl_entry; 1079 do { 1080 struct ctl_table_header *head = 1081 list_entry(tmp, struct ctl_table_header, ctl_entry); 1082 void *context = NULL; 1083 1084 if (!use_table(head)) 1085 continue; 1086 1087 spin_unlock(&sysctl_lock); 1088 1089 error = parse_table(name, nlen, oldval, oldlenp, 1090 newval, newlen, head->ctl_table, 1091 &context); 1092 kfree(context); 1093 1094 spin_lock(&sysctl_lock); 1095 unuse_table(head); 1096 if (error != -ENOTDIR) 1097 break; 1098 } while ((tmp = tmp->next) != &root_table_header.ctl_entry); 1099 spin_unlock(&sysctl_lock); 1100 return error; 1101 } 1102 1103 asmlinkage long sys_sysctl(struct __sysctl_args __user *args) 1104 { 1105 struct __sysctl_args tmp; 1106 int error; 1107 1108 if (copy_from_user(&tmp, args, sizeof(tmp))) 1109 return -EFAULT; 1110 1111 lock_kernel(); 1112 error = do_sysctl(tmp.name, tmp.nlen, tmp.oldval, tmp.oldlenp, 1113 tmp.newval, tmp.newlen); 1114 unlock_kernel(); 1115 return error; 1116 } 1117 1118 /* 1119 * ctl_perm does NOT grant the superuser all rights automatically, because 1120 * some sysctl variables are readonly even to root. 1121 */ 1122 1123 static int test_perm(int mode, int op) 1124 { 1125 if (!current->euid) 1126 mode >>= 6; 1127 else if (in_egroup_p(0)) 1128 mode >>= 3; 1129 if ((mode & op & 0007) == op) 1130 return 0; 1131 return -EACCES; 1132 } 1133 1134 static inline int ctl_perm(ctl_table *table, int op) 1135 { 1136 int error; 1137 error = security_sysctl(table, op); 1138 if (error) 1139 return error; 1140 return test_perm(table->mode, op); 1141 } 1142 1143 static int parse_table(int __user *name, int nlen, 1144 void __user *oldval, size_t __user *oldlenp, 1145 void __user *newval, size_t newlen, 1146 ctl_table *table, void **context) 1147 { 1148 int n; 1149 repeat: 1150 if (!nlen) 1151 return -ENOTDIR; 1152 if (get_user(n, name)) 1153 return -EFAULT; 1154 for ( ; table->ctl_name; table++) { 1155 if (n == table->ctl_name || table->ctl_name == CTL_ANY) { 1156 int error; 1157 if (table->child) { 1158 if (ctl_perm(table, 001)) 1159 return -EPERM; 1160 if (table->strategy) { 1161 error = table->strategy( 1162 table, name, nlen, 1163 oldval, oldlenp, 1164 newval, newlen, context); 1165 if (error) 1166 return error; 1167 } 1168 name++; 1169 nlen--; 1170 table = table->child; 1171 goto repeat; 1172 } 1173 error = do_sysctl_strategy(table, name, nlen, 1174 oldval, oldlenp, 1175 newval, newlen, context); 1176 return error; 1177 } 1178 } 1179 return -ENOTDIR; 1180 } 1181 1182 /* Perform the actual read/write of a sysctl table entry. */ 1183 int do_sysctl_strategy (ctl_table *table, 1184 int __user *name, int nlen, 1185 void __user *oldval, size_t __user *oldlenp, 1186 void __user *newval, size_t newlen, void **context) 1187 { 1188 int op = 0, rc; 1189 size_t len; 1190 1191 if (oldval) 1192 op |= 004; 1193 if (newval) 1194 op |= 002; 1195 if (ctl_perm(table, op)) 1196 return -EPERM; 1197 1198 if (table->strategy) { 1199 rc = table->strategy(table, name, nlen, oldval, oldlenp, 1200 newval, newlen, context); 1201 if (rc < 0) 1202 return rc; 1203 if (rc > 0) 1204 return 0; 1205 } 1206 1207 /* If there is no strategy routine, or if the strategy returns 1208 * zero, proceed with automatic r/w */ 1209 if (table->data && table->maxlen) { 1210 if (oldval && oldlenp) { 1211 if (get_user(len, oldlenp)) 1212 return -EFAULT; 1213 if (len) { 1214 if (len > table->maxlen) 1215 len = table->maxlen; 1216 if(copy_to_user(oldval, table->data, len)) 1217 return -EFAULT; 1218 if(put_user(len, oldlenp)) 1219 return -EFAULT; 1220 } 1221 } 1222 if (newval && newlen) { 1223 len = newlen; 1224 if (len > table->maxlen) 1225 len = table->maxlen; 1226 if(copy_from_user(table->data, newval, len)) 1227 return -EFAULT; 1228 } 1229 } 1230 return 0; 1231 } 1232 1233 /** 1234 * register_sysctl_table - register a sysctl hierarchy 1235 * @table: the top-level table structure 1236 * @insert_at_head: whether the entry should be inserted in front or at the end 1237 * 1238 * Register a sysctl table hierarchy. @table should be a filled in ctl_table 1239 * array. An entry with a ctl_name of 0 terminates the table. 1240 * 1241 * The members of the &ctl_table structure are used as follows: 1242 * 1243 * ctl_name - This is the numeric sysctl value used by sysctl(2). The number 1244 * must be unique within that level of sysctl 1245 * 1246 * procname - the name of the sysctl file under /proc/sys. Set to %NULL to not 1247 * enter a sysctl file 1248 * 1249 * data - a pointer to data for use by proc_handler 1250 * 1251 * maxlen - the maximum size in bytes of the data 1252 * 1253 * mode - the file permissions for the /proc/sys file, and for sysctl(2) 1254 * 1255 * child - a pointer to the child sysctl table if this entry is a directory, or 1256 * %NULL. 1257 * 1258 * proc_handler - the text handler routine (described below) 1259 * 1260 * strategy - the strategy routine (described below) 1261 * 1262 * de - for internal use by the sysctl routines 1263 * 1264 * extra1, extra2 - extra pointers usable by the proc handler routines 1265 * 1266 * Leaf nodes in the sysctl tree will be represented by a single file 1267 * under /proc; non-leaf nodes will be represented by directories. 1268 * 1269 * sysctl(2) can automatically manage read and write requests through 1270 * the sysctl table. The data and maxlen fields of the ctl_table 1271 * struct enable minimal validation of the values being written to be 1272 * performed, and the mode field allows minimal authentication. 1273 * 1274 * More sophisticated management can be enabled by the provision of a 1275 * strategy routine with the table entry. This will be called before 1276 * any automatic read or write of the data is performed. 1277 * 1278 * The strategy routine may return 1279 * 1280 * < 0 - Error occurred (error is passed to user process) 1281 * 1282 * 0 - OK - proceed with automatic read or write. 1283 * 1284 * > 0 - OK - read or write has been done by the strategy routine, so 1285 * return immediately. 1286 * 1287 * There must be a proc_handler routine for any terminal nodes 1288 * mirrored under /proc/sys (non-terminals are handled by a built-in 1289 * directory handler). Several default handlers are available to 1290 * cover common cases - 1291 * 1292 * proc_dostring(), proc_dointvec(), proc_dointvec_jiffies(), 1293 * proc_dointvec_userhz_jiffies(), proc_dointvec_minmax(), 1294 * proc_doulongvec_ms_jiffies_minmax(), proc_doulongvec_minmax() 1295 * 1296 * It is the handler's job to read the input buffer from user memory 1297 * and process it. The handler should return 0 on success. 1298 * 1299 * This routine returns %NULL on a failure to register, and a pointer 1300 * to the table header on success. 1301 */ 1302 struct ctl_table_header *register_sysctl_table(ctl_table * table, 1303 int insert_at_head) 1304 { 1305 struct ctl_table_header *tmp; 1306 tmp = kmalloc(sizeof(struct ctl_table_header), GFP_KERNEL); 1307 if (!tmp) 1308 return NULL; 1309 tmp->ctl_table = table; 1310 INIT_LIST_HEAD(&tmp->ctl_entry); 1311 tmp->used = 0; 1312 tmp->unregistering = NULL; 1313 spin_lock(&sysctl_lock); 1314 if (insert_at_head) 1315 list_add(&tmp->ctl_entry, &root_table_header.ctl_entry); 1316 else 1317 list_add_tail(&tmp->ctl_entry, &root_table_header.ctl_entry); 1318 spin_unlock(&sysctl_lock); 1319 #ifdef CONFIG_PROC_FS 1320 register_proc_table(table, proc_sys_root, tmp); 1321 #endif 1322 return tmp; 1323 } 1324 1325 /** 1326 * unregister_sysctl_table - unregister a sysctl table hierarchy 1327 * @header: the header returned from register_sysctl_table 1328 * 1329 * Unregisters the sysctl table and all children. proc entries may not 1330 * actually be removed until they are no longer used by anyone. 1331 */ 1332 void unregister_sysctl_table(struct ctl_table_header * header) 1333 { 1334 might_sleep(); 1335 spin_lock(&sysctl_lock); 1336 start_unregistering(header); 1337 #ifdef CONFIG_PROC_FS 1338 unregister_proc_table(header->ctl_table, proc_sys_root); 1339 #endif 1340 spin_unlock(&sysctl_lock); 1341 kfree(header); 1342 } 1343 1344 /* 1345 * /proc/sys support 1346 */ 1347 1348 #ifdef CONFIG_PROC_FS 1349 1350 /* Scan the sysctl entries in table and add them all into /proc */ 1351 static void register_proc_table(ctl_table * table, struct proc_dir_entry *root, void *set) 1352 { 1353 struct proc_dir_entry *de; 1354 int len; 1355 mode_t mode; 1356 1357 for (; table->ctl_name; table++) { 1358 /* Can't do anything without a proc name. */ 1359 if (!table->procname) 1360 continue; 1361 /* Maybe we can't do anything with it... */ 1362 if (!table->proc_handler && !table->child) { 1363 printk(KERN_WARNING "SYSCTL: Can't register %s\n", 1364 table->procname); 1365 continue; 1366 } 1367 1368 len = strlen(table->procname); 1369 mode = table->mode; 1370 1371 de = NULL; 1372 if (table->proc_handler) 1373 mode |= S_IFREG; 1374 else { 1375 mode |= S_IFDIR; 1376 for (de = root->subdir; de; de = de->next) { 1377 if (proc_match(len, table->procname, de)) 1378 break; 1379 } 1380 /* If the subdir exists already, de is non-NULL */ 1381 } 1382 1383 if (!de) { 1384 de = create_proc_entry(table->procname, mode, root); 1385 if (!de) 1386 continue; 1387 de->set = set; 1388 de->data = (void *) table; 1389 if (table->proc_handler) 1390 de->proc_fops = &proc_sys_file_operations; 1391 } 1392 table->de = de; 1393 if (de->mode & S_IFDIR) 1394 register_proc_table(table->child, de, set); 1395 } 1396 } 1397 1398 /* 1399 * Unregister a /proc sysctl table and any subdirectories. 1400 */ 1401 static void unregister_proc_table(ctl_table * table, struct proc_dir_entry *root) 1402 { 1403 struct proc_dir_entry *de; 1404 for (; table->ctl_name; table++) { 1405 if (!(de = table->de)) 1406 continue; 1407 if (de->mode & S_IFDIR) { 1408 if (!table->child) { 1409 printk (KERN_ALERT "Help - malformed sysctl tree on free\n"); 1410 continue; 1411 } 1412 unregister_proc_table(table->child, de); 1413 1414 /* Don't unregister directories which still have entries.. */ 1415 if (de->subdir) 1416 continue; 1417 } 1418 1419 /* 1420 * In any case, mark the entry as goner; we'll keep it 1421 * around if it's busy, but we'll know to do nothing with 1422 * its fields. We are under sysctl_lock here. 1423 */ 1424 de->data = NULL; 1425 1426 /* Don't unregister proc entries that are still being used.. */ 1427 if (atomic_read(&de->count)) 1428 continue; 1429 1430 table->de = NULL; 1431 remove_proc_entry(table->procname, root); 1432 } 1433 } 1434 1435 static ssize_t do_rw_proc(int write, struct file * file, char __user * buf, 1436 size_t count, loff_t *ppos) 1437 { 1438 int op; 1439 struct proc_dir_entry *de = PDE(file->f_dentry->d_inode); 1440 struct ctl_table *table; 1441 size_t res; 1442 ssize_t error = -ENOTDIR; 1443 1444 spin_lock(&sysctl_lock); 1445 if (de && de->data && use_table(de->set)) { 1446 /* 1447 * at that point we know that sysctl was not unregistered 1448 * and won't be until we finish 1449 */ 1450 spin_unlock(&sysctl_lock); 1451 table = (struct ctl_table *) de->data; 1452 if (!table || !table->proc_handler) 1453 goto out; 1454 error = -EPERM; 1455 op = (write ? 002 : 004); 1456 if (ctl_perm(table, op)) 1457 goto out; 1458 1459 /* careful: calling conventions are nasty here */ 1460 res = count; 1461 error = (*table->proc_handler)(table, write, file, 1462 buf, &res, ppos); 1463 if (!error) 1464 error = res; 1465 out: 1466 spin_lock(&sysctl_lock); 1467 unuse_table(de->set); 1468 } 1469 spin_unlock(&sysctl_lock); 1470 return error; 1471 } 1472 1473 static int proc_opensys(struct inode *inode, struct file *file) 1474 { 1475 if (file->f_mode & FMODE_WRITE) { 1476 /* 1477 * sysctl entries that are not writable, 1478 * are _NOT_ writable, capabilities or not. 1479 */ 1480 if (!(inode->i_mode & S_IWUSR)) 1481 return -EPERM; 1482 } 1483 1484 return 0; 1485 } 1486 1487 static ssize_t proc_readsys(struct file * file, char __user * buf, 1488 size_t count, loff_t *ppos) 1489 { 1490 return do_rw_proc(0, file, buf, count, ppos); 1491 } 1492 1493 static ssize_t proc_writesys(struct file * file, const char __user * buf, 1494 size_t count, loff_t *ppos) 1495 { 1496 return do_rw_proc(1, file, (char __user *) buf, count, ppos); 1497 } 1498 1499 /** 1500 * proc_dostring - read a string sysctl 1501 * @table: the sysctl table 1502 * @write: %TRUE if this is a write to the sysctl file 1503 * @filp: the file structure 1504 * @buffer: the user buffer 1505 * @lenp: the size of the user buffer 1506 * @ppos: file position 1507 * 1508 * Reads/writes a string from/to the user buffer. If the kernel 1509 * buffer provided is not large enough to hold the string, the 1510 * string is truncated. The copied string is %NULL-terminated. 1511 * If the string is being read by the user process, it is copied 1512 * and a newline '\n' is added. It is truncated if the buffer is 1513 * not large enough. 1514 * 1515 * Returns 0 on success. 1516 */ 1517 int proc_dostring(ctl_table *table, int write, struct file *filp, 1518 void __user *buffer, size_t *lenp, loff_t *ppos) 1519 { 1520 size_t len; 1521 char __user *p; 1522 char c; 1523 1524 if (!table->data || !table->maxlen || !*lenp || 1525 (*ppos && !write)) { 1526 *lenp = 0; 1527 return 0; 1528 } 1529 1530 if (write) { 1531 len = 0; 1532 p = buffer; 1533 while (len < *lenp) { 1534 if (get_user(c, p++)) 1535 return -EFAULT; 1536 if (c == 0 || c == '\n') 1537 break; 1538 len++; 1539 } 1540 if (len >= table->maxlen) 1541 len = table->maxlen-1; 1542 if(copy_from_user(table->data, buffer, len)) 1543 return -EFAULT; 1544 ((char *) table->data)[len] = 0; 1545 *ppos += *lenp; 1546 } else { 1547 len = strlen(table->data); 1548 if (len > table->maxlen) 1549 len = table->maxlen; 1550 if (len > *lenp) 1551 len = *lenp; 1552 if (len) 1553 if(copy_to_user(buffer, table->data, len)) 1554 return -EFAULT; 1555 if (len < *lenp) { 1556 if(put_user('\n', ((char __user *) buffer) + len)) 1557 return -EFAULT; 1558 len++; 1559 } 1560 *lenp = len; 1561 *ppos += len; 1562 } 1563 return 0; 1564 } 1565 1566 /* 1567 * Special case of dostring for the UTS structure. This has locks 1568 * to observe. Should this be in kernel/sys.c ???? 1569 */ 1570 1571 static int proc_doutsstring(ctl_table *table, int write, struct file *filp, 1572 void __user *buffer, size_t *lenp, loff_t *ppos) 1573 { 1574 int r; 1575 1576 if (!write) { 1577 down_read(&uts_sem); 1578 r=proc_dostring(table,0,filp,buffer,lenp, ppos); 1579 up_read(&uts_sem); 1580 } else { 1581 down_write(&uts_sem); 1582 r=proc_dostring(table,1,filp,buffer,lenp, ppos); 1583 up_write(&uts_sem); 1584 } 1585 return r; 1586 } 1587 1588 static int do_proc_dointvec_conv(int *negp, unsigned long *lvalp, 1589 int *valp, 1590 int write, void *data) 1591 { 1592 if (write) { 1593 *valp = *negp ? -*lvalp : *lvalp; 1594 } else { 1595 int val = *valp; 1596 if (val < 0) { 1597 *negp = -1; 1598 *lvalp = (unsigned long)-val; 1599 } else { 1600 *negp = 0; 1601 *lvalp = (unsigned long)val; 1602 } 1603 } 1604 return 0; 1605 } 1606 1607 static int do_proc_dointvec(ctl_table *table, int write, struct file *filp, 1608 void __user *buffer, size_t *lenp, loff_t *ppos, 1609 int (*conv)(int *negp, unsigned long *lvalp, int *valp, 1610 int write, void *data), 1611 void *data) 1612 { 1613 #define TMPBUFLEN 21 1614 int *i, vleft, first=1, neg, val; 1615 unsigned long lval; 1616 size_t left, len; 1617 1618 char buf[TMPBUFLEN], *p; 1619 char __user *s = buffer; 1620 1621 if (!table->data || !table->maxlen || !*lenp || 1622 (*ppos && !write)) { 1623 *lenp = 0; 1624 return 0; 1625 } 1626 1627 i = (int *) table->data; 1628 vleft = table->maxlen / sizeof(*i); 1629 left = *lenp; 1630 1631 if (!conv) 1632 conv = do_proc_dointvec_conv; 1633 1634 for (; left && vleft--; i++, first=0) { 1635 if (write) { 1636 while (left) { 1637 char c; 1638 if (get_user(c, s)) 1639 return -EFAULT; 1640 if (!isspace(c)) 1641 break; 1642 left--; 1643 s++; 1644 } 1645 if (!left) 1646 break; 1647 neg = 0; 1648 len = left; 1649 if (len > sizeof(buf) - 1) 1650 len = sizeof(buf) - 1; 1651 if (copy_from_user(buf, s, len)) 1652 return -EFAULT; 1653 buf[len] = 0; 1654 p = buf; 1655 if (*p == '-' && left > 1) { 1656 neg = 1; 1657 left--, p++; 1658 } 1659 if (*p < '0' || *p > '9') 1660 break; 1661 1662 lval = simple_strtoul(p, &p, 0); 1663 1664 len = p-buf; 1665 if ((len < left) && *p && !isspace(*p)) 1666 break; 1667 if (neg) 1668 val = -val; 1669 s += len; 1670 left -= len; 1671 1672 if (conv(&neg, &lval, i, 1, data)) 1673 break; 1674 } else { 1675 p = buf; 1676 if (!first) 1677 *p++ = '\t'; 1678 1679 if (conv(&neg, &lval, i, 0, data)) 1680 break; 1681 1682 sprintf(p, "%s%lu", neg ? "-" : "", lval); 1683 len = strlen(buf); 1684 if (len > left) 1685 len = left; 1686 if(copy_to_user(s, buf, len)) 1687 return -EFAULT; 1688 left -= len; 1689 s += len; 1690 } 1691 } 1692 1693 if (!write && !first && left) { 1694 if(put_user('\n', s)) 1695 return -EFAULT; 1696 left--, s++; 1697 } 1698 if (write) { 1699 while (left) { 1700 char c; 1701 if (get_user(c, s++)) 1702 return -EFAULT; 1703 if (!isspace(c)) 1704 break; 1705 left--; 1706 } 1707 } 1708 if (write && first) 1709 return -EINVAL; 1710 *lenp -= left; 1711 *ppos += *lenp; 1712 return 0; 1713 #undef TMPBUFLEN 1714 } 1715 1716 /** 1717 * proc_dointvec - read a vector of integers 1718 * @table: the sysctl table 1719 * @write: %TRUE if this is a write to the sysctl file 1720 * @filp: the file structure 1721 * @buffer: the user buffer 1722 * @lenp: the size of the user buffer 1723 * @ppos: file position 1724 * 1725 * Reads/writes up to table->maxlen/sizeof(unsigned int) integer 1726 * values from/to the user buffer, treated as an ASCII string. 1727 * 1728 * Returns 0 on success. 1729 */ 1730 int proc_dointvec(ctl_table *table, int write, struct file *filp, 1731 void __user *buffer, size_t *lenp, loff_t *ppos) 1732 { 1733 return do_proc_dointvec(table,write,filp,buffer,lenp,ppos, 1734 NULL,NULL); 1735 } 1736 1737 #define OP_SET 0 1738 #define OP_AND 1 1739 #define OP_OR 2 1740 #define OP_MAX 3 1741 #define OP_MIN 4 1742 1743 static int do_proc_dointvec_bset_conv(int *negp, unsigned long *lvalp, 1744 int *valp, 1745 int write, void *data) 1746 { 1747 int op = *(int *)data; 1748 if (write) { 1749 int val = *negp ? -*lvalp : *lvalp; 1750 switch(op) { 1751 case OP_SET: *valp = val; break; 1752 case OP_AND: *valp &= val; break; 1753 case OP_OR: *valp |= val; break; 1754 case OP_MAX: if(*valp < val) 1755 *valp = val; 1756 break; 1757 case OP_MIN: if(*valp > val) 1758 *valp = val; 1759 break; 1760 } 1761 } else { 1762 int val = *valp; 1763 if (val < 0) { 1764 *negp = -1; 1765 *lvalp = (unsigned long)-val; 1766 } else { 1767 *negp = 0; 1768 *lvalp = (unsigned long)val; 1769 } 1770 } 1771 return 0; 1772 } 1773 1774 /* 1775 * init may raise the set. 1776 */ 1777 1778 int proc_dointvec_bset(ctl_table *table, int write, struct file *filp, 1779 void __user *buffer, size_t *lenp, loff_t *ppos) 1780 { 1781 int op; 1782 1783 if (!capable(CAP_SYS_MODULE)) { 1784 return -EPERM; 1785 } 1786 1787 op = (current->pid == 1) ? OP_SET : OP_AND; 1788 return do_proc_dointvec(table,write,filp,buffer,lenp,ppos, 1789 do_proc_dointvec_bset_conv,&op); 1790 } 1791 1792 struct do_proc_dointvec_minmax_conv_param { 1793 int *min; 1794 int *max; 1795 }; 1796 1797 static int do_proc_dointvec_minmax_conv(int *negp, unsigned long *lvalp, 1798 int *valp, 1799 int write, void *data) 1800 { 1801 struct do_proc_dointvec_minmax_conv_param *param = data; 1802 if (write) { 1803 int val = *negp ? -*lvalp : *lvalp; 1804 if ((param->min && *param->min > val) || 1805 (param->max && *param->max < val)) 1806 return -EINVAL; 1807 *valp = val; 1808 } else { 1809 int val = *valp; 1810 if (val < 0) { 1811 *negp = -1; 1812 *lvalp = (unsigned long)-val; 1813 } else { 1814 *negp = 0; 1815 *lvalp = (unsigned long)val; 1816 } 1817 } 1818 return 0; 1819 } 1820 1821 /** 1822 * proc_dointvec_minmax - read a vector of integers with min/max values 1823 * @table: the sysctl table 1824 * @write: %TRUE if this is a write to the sysctl file 1825 * @filp: the file structure 1826 * @buffer: the user buffer 1827 * @lenp: the size of the user buffer 1828 * @ppos: file position 1829 * 1830 * Reads/writes up to table->maxlen/sizeof(unsigned int) integer 1831 * values from/to the user buffer, treated as an ASCII string. 1832 * 1833 * This routine will ensure the values are within the range specified by 1834 * table->extra1 (min) and table->extra2 (max). 1835 * 1836 * Returns 0 on success. 1837 */ 1838 int proc_dointvec_minmax(ctl_table *table, int write, struct file *filp, 1839 void __user *buffer, size_t *lenp, loff_t *ppos) 1840 { 1841 struct do_proc_dointvec_minmax_conv_param param = { 1842 .min = (int *) table->extra1, 1843 .max = (int *) table->extra2, 1844 }; 1845 return do_proc_dointvec(table, write, filp, buffer, lenp, ppos, 1846 do_proc_dointvec_minmax_conv, ¶m); 1847 } 1848 1849 static int do_proc_doulongvec_minmax(ctl_table *table, int write, 1850 struct file *filp, 1851 void __user *buffer, 1852 size_t *lenp, loff_t *ppos, 1853 unsigned long convmul, 1854 unsigned long convdiv) 1855 { 1856 #define TMPBUFLEN 21 1857 unsigned long *i, *min, *max, val; 1858 int vleft, first=1, neg; 1859 size_t len, left; 1860 char buf[TMPBUFLEN], *p; 1861 char __user *s = buffer; 1862 1863 if (!table->data || !table->maxlen || !*lenp || 1864 (*ppos && !write)) { 1865 *lenp = 0; 1866 return 0; 1867 } 1868 1869 i = (unsigned long *) table->data; 1870 min = (unsigned long *) table->extra1; 1871 max = (unsigned long *) table->extra2; 1872 vleft = table->maxlen / sizeof(unsigned long); 1873 left = *lenp; 1874 1875 for (; left && vleft--; i++, min++, max++, first=0) { 1876 if (write) { 1877 while (left) { 1878 char c; 1879 if (get_user(c, s)) 1880 return -EFAULT; 1881 if (!isspace(c)) 1882 break; 1883 left--; 1884 s++; 1885 } 1886 if (!left) 1887 break; 1888 neg = 0; 1889 len = left; 1890 if (len > TMPBUFLEN-1) 1891 len = TMPBUFLEN-1; 1892 if (copy_from_user(buf, s, len)) 1893 return -EFAULT; 1894 buf[len] = 0; 1895 p = buf; 1896 if (*p == '-' && left > 1) { 1897 neg = 1; 1898 left--, p++; 1899 } 1900 if (*p < '0' || *p > '9') 1901 break; 1902 val = simple_strtoul(p, &p, 0) * convmul / convdiv ; 1903 len = p-buf; 1904 if ((len < left) && *p && !isspace(*p)) 1905 break; 1906 if (neg) 1907 val = -val; 1908 s += len; 1909 left -= len; 1910 1911 if(neg) 1912 continue; 1913 if ((min && val < *min) || (max && val > *max)) 1914 continue; 1915 *i = val; 1916 } else { 1917 p = buf; 1918 if (!first) 1919 *p++ = '\t'; 1920 sprintf(p, "%lu", convdiv * (*i) / convmul); 1921 len = strlen(buf); 1922 if (len > left) 1923 len = left; 1924 if(copy_to_user(s, buf, len)) 1925 return -EFAULT; 1926 left -= len; 1927 s += len; 1928 } 1929 } 1930 1931 if (!write && !first && left) { 1932 if(put_user('\n', s)) 1933 return -EFAULT; 1934 left--, s++; 1935 } 1936 if (write) { 1937 while (left) { 1938 char c; 1939 if (get_user(c, s++)) 1940 return -EFAULT; 1941 if (!isspace(c)) 1942 break; 1943 left--; 1944 } 1945 } 1946 if (write && first) 1947 return -EINVAL; 1948 *lenp -= left; 1949 *ppos += *lenp; 1950 return 0; 1951 #undef TMPBUFLEN 1952 } 1953 1954 /** 1955 * proc_doulongvec_minmax - read a vector of long integers with min/max values 1956 * @table: the sysctl table 1957 * @write: %TRUE if this is a write to the sysctl file 1958 * @filp: the file structure 1959 * @buffer: the user buffer 1960 * @lenp: the size of the user buffer 1961 * @ppos: file position 1962 * 1963 * Reads/writes up to table->maxlen/sizeof(unsigned long) unsigned long 1964 * values from/to the user buffer, treated as an ASCII string. 1965 * 1966 * This routine will ensure the values are within the range specified by 1967 * table->extra1 (min) and table->extra2 (max). 1968 * 1969 * Returns 0 on success. 1970 */ 1971 int proc_doulongvec_minmax(ctl_table *table, int write, struct file *filp, 1972 void __user *buffer, size_t *lenp, loff_t *ppos) 1973 { 1974 return do_proc_doulongvec_minmax(table, write, filp, buffer, lenp, ppos, 1l, 1l); 1975 } 1976 1977 /** 1978 * proc_doulongvec_ms_jiffies_minmax - read a vector of millisecond values with min/max values 1979 * @table: the sysctl table 1980 * @write: %TRUE if this is a write to the sysctl file 1981 * @filp: the file structure 1982 * @buffer: the user buffer 1983 * @lenp: the size of the user buffer 1984 * @ppos: file position 1985 * 1986 * Reads/writes up to table->maxlen/sizeof(unsigned long) unsigned long 1987 * values from/to the user buffer, treated as an ASCII string. The values 1988 * are treated as milliseconds, and converted to jiffies when they are stored. 1989 * 1990 * This routine will ensure the values are within the range specified by 1991 * table->extra1 (min) and table->extra2 (max). 1992 * 1993 * Returns 0 on success. 1994 */ 1995 int proc_doulongvec_ms_jiffies_minmax(ctl_table *table, int write, 1996 struct file *filp, 1997 void __user *buffer, 1998 size_t *lenp, loff_t *ppos) 1999 { 2000 return do_proc_doulongvec_minmax(table, write, filp, buffer, 2001 lenp, ppos, HZ, 1000l); 2002 } 2003 2004 2005 static int do_proc_dointvec_jiffies_conv(int *negp, unsigned long *lvalp, 2006 int *valp, 2007 int write, void *data) 2008 { 2009 if (write) { 2010 *valp = *negp ? -(*lvalp*HZ) : (*lvalp*HZ); 2011 } else { 2012 int val = *valp; 2013 unsigned long lval; 2014 if (val < 0) { 2015 *negp = -1; 2016 lval = (unsigned long)-val; 2017 } else { 2018 *negp = 0; 2019 lval = (unsigned long)val; 2020 } 2021 *lvalp = lval / HZ; 2022 } 2023 return 0; 2024 } 2025 2026 static int do_proc_dointvec_userhz_jiffies_conv(int *negp, unsigned long *lvalp, 2027 int *valp, 2028 int write, void *data) 2029 { 2030 if (write) { 2031 *valp = clock_t_to_jiffies(*negp ? -*lvalp : *lvalp); 2032 } else { 2033 int val = *valp; 2034 unsigned long lval; 2035 if (val < 0) { 2036 *negp = -1; 2037 lval = (unsigned long)-val; 2038 } else { 2039 *negp = 0; 2040 lval = (unsigned long)val; 2041 } 2042 *lvalp = jiffies_to_clock_t(lval); 2043 } 2044 return 0; 2045 } 2046 2047 static int do_proc_dointvec_ms_jiffies_conv(int *negp, unsigned long *lvalp, 2048 int *valp, 2049 int write, void *data) 2050 { 2051 if (write) { 2052 *valp = msecs_to_jiffies(*negp ? -*lvalp : *lvalp); 2053 } else { 2054 int val = *valp; 2055 unsigned long lval; 2056 if (val < 0) { 2057 *negp = -1; 2058 lval = (unsigned long)-val; 2059 } else { 2060 *negp = 0; 2061 lval = (unsigned long)val; 2062 } 2063 *lvalp = jiffies_to_msecs(lval); 2064 } 2065 return 0; 2066 } 2067 2068 /** 2069 * proc_dointvec_jiffies - read a vector of integers as seconds 2070 * @table: the sysctl table 2071 * @write: %TRUE if this is a write to the sysctl file 2072 * @filp: the file structure 2073 * @buffer: the user buffer 2074 * @lenp: the size of the user buffer 2075 * @ppos: file position 2076 * 2077 * Reads/writes up to table->maxlen/sizeof(unsigned int) integer 2078 * values from/to the user buffer, treated as an ASCII string. 2079 * The values read are assumed to be in seconds, and are converted into 2080 * jiffies. 2081 * 2082 * Returns 0 on success. 2083 */ 2084 int proc_dointvec_jiffies(ctl_table *table, int write, struct file *filp, 2085 void __user *buffer, size_t *lenp, loff_t *ppos) 2086 { 2087 return do_proc_dointvec(table,write,filp,buffer,lenp,ppos, 2088 do_proc_dointvec_jiffies_conv,NULL); 2089 } 2090 2091 /** 2092 * proc_dointvec_userhz_jiffies - read a vector of integers as 1/USER_HZ seconds 2093 * @table: the sysctl table 2094 * @write: %TRUE if this is a write to the sysctl file 2095 * @filp: the file structure 2096 * @buffer: the user buffer 2097 * @lenp: the size of the user buffer 2098 * @ppos: pointer to the file position 2099 * 2100 * Reads/writes up to table->maxlen/sizeof(unsigned int) integer 2101 * values from/to the user buffer, treated as an ASCII string. 2102 * The values read are assumed to be in 1/USER_HZ seconds, and 2103 * are converted into jiffies. 2104 * 2105 * Returns 0 on success. 2106 */ 2107 int proc_dointvec_userhz_jiffies(ctl_table *table, int write, struct file *filp, 2108 void __user *buffer, size_t *lenp, loff_t *ppos) 2109 { 2110 return do_proc_dointvec(table,write,filp,buffer,lenp,ppos, 2111 do_proc_dointvec_userhz_jiffies_conv,NULL); 2112 } 2113 2114 /** 2115 * proc_dointvec_ms_jiffies - read a vector of integers as 1 milliseconds 2116 * @table: the sysctl table 2117 * @write: %TRUE if this is a write to the sysctl file 2118 * @filp: the file structure 2119 * @buffer: the user buffer 2120 * @lenp: the size of the user buffer 2121 * @ppos: file position 2122 * @ppos: the current position in the file 2123 * 2124 * Reads/writes up to table->maxlen/sizeof(unsigned int) integer 2125 * values from/to the user buffer, treated as an ASCII string. 2126 * The values read are assumed to be in 1/1000 seconds, and 2127 * are converted into jiffies. 2128 * 2129 * Returns 0 on success. 2130 */ 2131 int proc_dointvec_ms_jiffies(ctl_table *table, int write, struct file *filp, 2132 void __user *buffer, size_t *lenp, loff_t *ppos) 2133 { 2134 return do_proc_dointvec(table, write, filp, buffer, lenp, ppos, 2135 do_proc_dointvec_ms_jiffies_conv, NULL); 2136 } 2137 2138 #else /* CONFIG_PROC_FS */ 2139 2140 int proc_dostring(ctl_table *table, int write, struct file *filp, 2141 void __user *buffer, size_t *lenp, loff_t *ppos) 2142 { 2143 return -ENOSYS; 2144 } 2145 2146 static int proc_doutsstring(ctl_table *table, int write, struct file *filp, 2147 void __user *buffer, size_t *lenp, loff_t *ppos) 2148 { 2149 return -ENOSYS; 2150 } 2151 2152 int proc_dointvec(ctl_table *table, int write, struct file *filp, 2153 void __user *buffer, size_t *lenp, loff_t *ppos) 2154 { 2155 return -ENOSYS; 2156 } 2157 2158 int proc_dointvec_bset(ctl_table *table, int write, struct file *filp, 2159 void __user *buffer, size_t *lenp, loff_t *ppos) 2160 { 2161 return -ENOSYS; 2162 } 2163 2164 int proc_dointvec_minmax(ctl_table *table, int write, struct file *filp, 2165 void __user *buffer, size_t *lenp, loff_t *ppos) 2166 { 2167 return -ENOSYS; 2168 } 2169 2170 int proc_dointvec_jiffies(ctl_table *table, int write, struct file *filp, 2171 void __user *buffer, size_t *lenp, loff_t *ppos) 2172 { 2173 return -ENOSYS; 2174 } 2175 2176 int proc_dointvec_userhz_jiffies(ctl_table *table, int write, struct file *filp, 2177 void __user *buffer, size_t *lenp, loff_t *ppos) 2178 { 2179 return -ENOSYS; 2180 } 2181 2182 int proc_dointvec_ms_jiffies(ctl_table *table, int write, struct file *filp, 2183 void __user *buffer, size_t *lenp, loff_t *ppos) 2184 { 2185 return -ENOSYS; 2186 } 2187 2188 int proc_doulongvec_minmax(ctl_table *table, int write, struct file *filp, 2189 void __user *buffer, size_t *lenp, loff_t *ppos) 2190 { 2191 return -ENOSYS; 2192 } 2193 2194 int proc_doulongvec_ms_jiffies_minmax(ctl_table *table, int write, 2195 struct file *filp, 2196 void __user *buffer, 2197 size_t *lenp, loff_t *ppos) 2198 { 2199 return -ENOSYS; 2200 } 2201 2202 2203 #endif /* CONFIG_PROC_FS */ 2204 2205 2206 /* 2207 * General sysctl support routines 2208 */ 2209 2210 /* The generic string strategy routine: */ 2211 int sysctl_string(ctl_table *table, int __user *name, int nlen, 2212 void __user *oldval, size_t __user *oldlenp, 2213 void __user *newval, size_t newlen, void **context) 2214 { 2215 if (!table->data || !table->maxlen) 2216 return -ENOTDIR; 2217 2218 if (oldval && oldlenp) { 2219 size_t bufsize; 2220 if (get_user(bufsize, oldlenp)) 2221 return -EFAULT; 2222 if (bufsize) { 2223 size_t len = strlen(table->data), copied; 2224 2225 /* This shouldn't trigger for a well-formed sysctl */ 2226 if (len > table->maxlen) 2227 len = table->maxlen; 2228 2229 /* Copy up to a max of bufsize-1 bytes of the string */ 2230 copied = (len >= bufsize) ? bufsize - 1 : len; 2231 2232 if (copy_to_user(oldval, table->data, copied) || 2233 put_user(0, (char __user *)(oldval + copied))) 2234 return -EFAULT; 2235 if (put_user(len, oldlenp)) 2236 return -EFAULT; 2237 } 2238 } 2239 if (newval && newlen) { 2240 size_t len = newlen; 2241 if (len > table->maxlen) 2242 len = table->maxlen; 2243 if(copy_from_user(table->data, newval, len)) 2244 return -EFAULT; 2245 if (len == table->maxlen) 2246 len--; 2247 ((char *) table->data)[len] = 0; 2248 } 2249 return 1; 2250 } 2251 2252 /* 2253 * This function makes sure that all of the integers in the vector 2254 * are between the minimum and maximum values given in the arrays 2255 * table->extra1 and table->extra2, respectively. 2256 */ 2257 int sysctl_intvec(ctl_table *table, int __user *name, int nlen, 2258 void __user *oldval, size_t __user *oldlenp, 2259 void __user *newval, size_t newlen, void **context) 2260 { 2261 2262 if (newval && newlen) { 2263 int __user *vec = (int __user *) newval; 2264 int *min = (int *) table->extra1; 2265 int *max = (int *) table->extra2; 2266 size_t length; 2267 int i; 2268 2269 if (newlen % sizeof(int) != 0) 2270 return -EINVAL; 2271 2272 if (!table->extra1 && !table->extra2) 2273 return 0; 2274 2275 if (newlen > table->maxlen) 2276 newlen = table->maxlen; 2277 length = newlen / sizeof(int); 2278 2279 for (i = 0; i < length; i++) { 2280 int value; 2281 if (get_user(value, vec + i)) 2282 return -EFAULT; 2283 if (min && value < min[i]) 2284 return -EINVAL; 2285 if (max && value > max[i]) 2286 return -EINVAL; 2287 } 2288 } 2289 return 0; 2290 } 2291 2292 /* Strategy function to convert jiffies to seconds */ 2293 int sysctl_jiffies(ctl_table *table, int __user *name, int nlen, 2294 void __user *oldval, size_t __user *oldlenp, 2295 void __user *newval, size_t newlen, void **context) 2296 { 2297 if (oldval) { 2298 size_t olen; 2299 if (oldlenp) { 2300 if (get_user(olen, oldlenp)) 2301 return -EFAULT; 2302 if (olen!=sizeof(int)) 2303 return -EINVAL; 2304 } 2305 if (put_user(*(int *)(table->data)/HZ, (int __user *)oldval) || 2306 (oldlenp && put_user(sizeof(int),oldlenp))) 2307 return -EFAULT; 2308 } 2309 if (newval && newlen) { 2310 int new; 2311 if (newlen != sizeof(int)) 2312 return -EINVAL; 2313 if (get_user(new, (int __user *)newval)) 2314 return -EFAULT; 2315 *(int *)(table->data) = new*HZ; 2316 } 2317 return 1; 2318 } 2319 2320 /* Strategy function to convert jiffies to seconds */ 2321 int sysctl_ms_jiffies(ctl_table *table, int __user *name, int nlen, 2322 void __user *oldval, size_t __user *oldlenp, 2323 void __user *newval, size_t newlen, void **context) 2324 { 2325 if (oldval) { 2326 size_t olen; 2327 if (oldlenp) { 2328 if (get_user(olen, oldlenp)) 2329 return -EFAULT; 2330 if (olen!=sizeof(int)) 2331 return -EINVAL; 2332 } 2333 if (put_user(jiffies_to_msecs(*(int *)(table->data)), (int __user *)oldval) || 2334 (oldlenp && put_user(sizeof(int),oldlenp))) 2335 return -EFAULT; 2336 } 2337 if (newval && newlen) { 2338 int new; 2339 if (newlen != sizeof(int)) 2340 return -EINVAL; 2341 if (get_user(new, (int __user *)newval)) 2342 return -EFAULT; 2343 *(int *)(table->data) = msecs_to_jiffies(new); 2344 } 2345 return 1; 2346 } 2347 2348 #else /* CONFIG_SYSCTL */ 2349 2350 2351 asmlinkage long sys_sysctl(struct __sysctl_args __user *args) 2352 { 2353 return -ENOSYS; 2354 } 2355 2356 int sysctl_string(ctl_table *table, int __user *name, int nlen, 2357 void __user *oldval, size_t __user *oldlenp, 2358 void __user *newval, size_t newlen, void **context) 2359 { 2360 return -ENOSYS; 2361 } 2362 2363 int sysctl_intvec(ctl_table *table, int __user *name, int nlen, 2364 void __user *oldval, size_t __user *oldlenp, 2365 void __user *newval, size_t newlen, void **context) 2366 { 2367 return -ENOSYS; 2368 } 2369 2370 int sysctl_jiffies(ctl_table *table, int __user *name, int nlen, 2371 void __user *oldval, size_t __user *oldlenp, 2372 void __user *newval, size_t newlen, void **context) 2373 { 2374 return -ENOSYS; 2375 } 2376 2377 int sysctl_ms_jiffies(ctl_table *table, int __user *name, int nlen, 2378 void __user *oldval, size_t __user *oldlenp, 2379 void __user *newval, size_t newlen, void **context) 2380 { 2381 return -ENOSYS; 2382 } 2383 2384 int proc_dostring(ctl_table *table, int write, struct file *filp, 2385 void __user *buffer, size_t *lenp, loff_t *ppos) 2386 { 2387 return -ENOSYS; 2388 } 2389 2390 int proc_dointvec(ctl_table *table, int write, struct file *filp, 2391 void __user *buffer, size_t *lenp, loff_t *ppos) 2392 { 2393 return -ENOSYS; 2394 } 2395 2396 int proc_dointvec_bset(ctl_table *table, int write, struct file *filp, 2397 void __user *buffer, size_t *lenp, loff_t *ppos) 2398 { 2399 return -ENOSYS; 2400 } 2401 2402 int proc_dointvec_minmax(ctl_table *table, int write, struct file *filp, 2403 void __user *buffer, size_t *lenp, loff_t *ppos) 2404 { 2405 return -ENOSYS; 2406 } 2407 2408 int proc_dointvec_jiffies(ctl_table *table, int write, struct file *filp, 2409 void __user *buffer, size_t *lenp, loff_t *ppos) 2410 { 2411 return -ENOSYS; 2412 } 2413 2414 int proc_dointvec_userhz_jiffies(ctl_table *table, int write, struct file *filp, 2415 void __user *buffer, size_t *lenp, loff_t *ppos) 2416 { 2417 return -ENOSYS; 2418 } 2419 2420 int proc_dointvec_ms_jiffies(ctl_table *table, int write, struct file *filp, 2421 void __user *buffer, size_t *lenp, loff_t *ppos) 2422 { 2423 return -ENOSYS; 2424 } 2425 2426 int proc_doulongvec_minmax(ctl_table *table, int write, struct file *filp, 2427 void __user *buffer, size_t *lenp, loff_t *ppos) 2428 { 2429 return -ENOSYS; 2430 } 2431 2432 int proc_doulongvec_ms_jiffies_minmax(ctl_table *table, int write, 2433 struct file *filp, 2434 void __user *buffer, 2435 size_t *lenp, loff_t *ppos) 2436 { 2437 return -ENOSYS; 2438 } 2439 2440 struct ctl_table_header * register_sysctl_table(ctl_table * table, 2441 int insert_at_head) 2442 { 2443 return NULL; 2444 } 2445 2446 void unregister_sysctl_table(struct ctl_table_header * table) 2447 { 2448 } 2449 2450 #endif /* CONFIG_SYSCTL */ 2451 2452 /* 2453 * No sense putting this after each symbol definition, twice, 2454 * exception granted :-) 2455 */ 2456 EXPORT_SYMBOL(proc_dointvec); 2457 EXPORT_SYMBOL(proc_dointvec_jiffies); 2458 EXPORT_SYMBOL(proc_dointvec_minmax); 2459 EXPORT_SYMBOL(proc_dointvec_userhz_jiffies); 2460 EXPORT_SYMBOL(proc_dointvec_ms_jiffies); 2461 EXPORT_SYMBOL(proc_dostring); 2462 EXPORT_SYMBOL(proc_doulongvec_minmax); 2463 EXPORT_SYMBOL(proc_doulongvec_ms_jiffies_minmax); 2464 EXPORT_SYMBOL(register_sysctl_table); 2465 EXPORT_SYMBOL(sysctl_intvec); 2466 EXPORT_SYMBOL(sysctl_jiffies); 2467 EXPORT_SYMBOL(sysctl_ms_jiffies); 2468 EXPORT_SYMBOL(sysctl_string); 2469 EXPORT_SYMBOL(unregister_sysctl_table); 2470