Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1 | /* |
| 2 | * linux/kernel/sys.c |
| 3 | * |
| 4 | * Copyright (C) 1991, 1992 Linus Torvalds |
| 5 | */ |
| 6 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 7 | #include <linux/module.h> |
| 8 | #include <linux/mm.h> |
| 9 | #include <linux/utsname.h> |
| 10 | #include <linux/mman.h> |
| 11 | #include <linux/smp_lock.h> |
| 12 | #include <linux/notifier.h> |
| 13 | #include <linux/reboot.h> |
| 14 | #include <linux/prctl.h> |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 15 | #include <linux/highuid.h> |
| 16 | #include <linux/fs.h> |
Daniel Walker | 3e88c55 | 2007-05-10 22:22:53 -0700 | [diff] [blame] | 17 | #include <linux/resource.h> |
Eric W. Biederman | dc009d9 | 2005-06-25 14:57:52 -0700 | [diff] [blame] | 18 | #include <linux/kernel.h> |
| 19 | #include <linux/kexec.h> |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 20 | #include <linux/workqueue.h> |
Randy.Dunlap | c59ede7 | 2006-01-11 12:17:46 -0800 | [diff] [blame] | 21 | #include <linux/capability.h> |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 22 | #include <linux/device.h> |
| 23 | #include <linux/key.h> |
| 24 | #include <linux/times.h> |
| 25 | #include <linux/posix-timers.h> |
| 26 | #include <linux/security.h> |
| 27 | #include <linux/dcookies.h> |
| 28 | #include <linux/suspend.h> |
| 29 | #include <linux/tty.h> |
Jesper Juhl | 7ed20e1 | 2005-05-01 08:59:14 -0700 | [diff] [blame] | 30 | #include <linux/signal.h> |
Matt Helsley | 9f46080 | 2005-11-07 00:59:16 -0800 | [diff] [blame] | 31 | #include <linux/cn_proc.h> |
Andi Kleen | 3cfc348 | 2006-09-26 10:52:28 +0200 | [diff] [blame] | 32 | #include <linux/getcpu.h> |
Eric Dumazet | 6eaeeab | 2007-05-10 22:22:37 -0700 | [diff] [blame] | 33 | #include <linux/task_io_accounting_ops.h> |
Andrea Arcangeli | 1d9d02f | 2007-07-15 23:41:32 -0700 | [diff] [blame] | 34 | #include <linux/seccomp.h> |
Mark Lord | 4047727 | 2007-10-01 01:20:10 -0700 | [diff] [blame] | 35 | #include <linux/cpu.h> |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 36 | |
| 37 | #include <linux/compat.h> |
| 38 | #include <linux/syscalls.h> |
Keshavamurthy Anil S | 00d7c05 | 2005-12-12 00:37:33 -0800 | [diff] [blame] | 39 | #include <linux/kprobes.h> |
Cedric Le Goater | acce292 | 2007-07-15 23:40:59 -0700 | [diff] [blame] | 40 | #include <linux/user_namespace.h> |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 41 | |
| 42 | #include <asm/uaccess.h> |
| 43 | #include <asm/io.h> |
| 44 | #include <asm/unistd.h> |
| 45 | |
| 46 | #ifndef SET_UNALIGN_CTL |
| 47 | # define SET_UNALIGN_CTL(a,b) (-EINVAL) |
| 48 | #endif |
| 49 | #ifndef GET_UNALIGN_CTL |
| 50 | # define GET_UNALIGN_CTL(a,b) (-EINVAL) |
| 51 | #endif |
| 52 | #ifndef SET_FPEMU_CTL |
| 53 | # define SET_FPEMU_CTL(a,b) (-EINVAL) |
| 54 | #endif |
| 55 | #ifndef GET_FPEMU_CTL |
| 56 | # define GET_FPEMU_CTL(a,b) (-EINVAL) |
| 57 | #endif |
| 58 | #ifndef SET_FPEXC_CTL |
| 59 | # define SET_FPEXC_CTL(a,b) (-EINVAL) |
| 60 | #endif |
| 61 | #ifndef GET_FPEXC_CTL |
| 62 | # define GET_FPEXC_CTL(a,b) (-EINVAL) |
| 63 | #endif |
Anton Blanchard | 651d765 | 2006-06-07 16:10:19 +1000 | [diff] [blame] | 64 | #ifndef GET_ENDIAN |
| 65 | # define GET_ENDIAN(a,b) (-EINVAL) |
| 66 | #endif |
| 67 | #ifndef SET_ENDIAN |
| 68 | # define SET_ENDIAN(a,b) (-EINVAL) |
| 69 | #endif |
Erik Bosman | 8fb402b | 2008-04-11 18:54:17 +0200 | [diff] [blame] | 70 | #ifndef GET_TSC_CTL |
| 71 | # define GET_TSC_CTL(a) (-EINVAL) |
| 72 | #endif |
| 73 | #ifndef SET_TSC_CTL |
| 74 | # define SET_TSC_CTL(a) (-EINVAL) |
| 75 | #endif |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 76 | |
| 77 | /* |
| 78 | * this is where the system-wide overflow UID and GID are defined, for |
| 79 | * architectures that now have 32-bit UID/GID but didn't in the past |
| 80 | */ |
| 81 | |
| 82 | int overflowuid = DEFAULT_OVERFLOWUID; |
| 83 | int overflowgid = DEFAULT_OVERFLOWGID; |
| 84 | |
| 85 | #ifdef CONFIG_UID16 |
| 86 | EXPORT_SYMBOL(overflowuid); |
| 87 | EXPORT_SYMBOL(overflowgid); |
| 88 | #endif |
| 89 | |
| 90 | /* |
| 91 | * the same as above, but for filesystems which can only store a 16-bit |
| 92 | * UID and GID. as such, this is needed on all architectures |
| 93 | */ |
| 94 | |
| 95 | int fs_overflowuid = DEFAULT_FS_OVERFLOWUID; |
| 96 | int fs_overflowgid = DEFAULT_FS_OVERFLOWUID; |
| 97 | |
| 98 | EXPORT_SYMBOL(fs_overflowuid); |
| 99 | EXPORT_SYMBOL(fs_overflowgid); |
| 100 | |
| 101 | /* |
| 102 | * this indicates whether you can reboot with ctrl-alt-del: the default is yes |
| 103 | */ |
| 104 | |
| 105 | int C_A_D = 1; |
Cedric Le Goater | 9ec5209 | 2006-10-02 02:19:00 -0700 | [diff] [blame] | 106 | struct pid *cad_pid; |
| 107 | EXPORT_SYMBOL(cad_pid); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 108 | |
| 109 | /* |
Rafael J. Wysocki | bd804eb | 2007-07-19 01:47:40 -0700 | [diff] [blame] | 110 | * If set, this is used for preparing the system to power off. |
| 111 | */ |
| 112 | |
| 113 | void (*pm_power_off_prepare)(void); |
Rafael J. Wysocki | bd804eb | 2007-07-19 01:47:40 -0700 | [diff] [blame] | 114 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 115 | static int set_one_prio(struct task_struct *p, int niceval, int error) |
| 116 | { |
| 117 | int no_nice; |
| 118 | |
| 119 | if (p->uid != current->euid && |
| 120 | p->euid != current->euid && !capable(CAP_SYS_NICE)) { |
| 121 | error = -EPERM; |
| 122 | goto out; |
| 123 | } |
Matt Mackall | e43379f | 2005-05-01 08:59:00 -0700 | [diff] [blame] | 124 | if (niceval < task_nice(p) && !can_nice(p, niceval)) { |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 125 | error = -EACCES; |
| 126 | goto out; |
| 127 | } |
| 128 | no_nice = security_task_setnice(p, niceval); |
| 129 | if (no_nice) { |
| 130 | error = no_nice; |
| 131 | goto out; |
| 132 | } |
| 133 | if (error == -ESRCH) |
| 134 | error = 0; |
| 135 | set_user_nice(p, niceval); |
| 136 | out: |
| 137 | return error; |
| 138 | } |
| 139 | |
| 140 | asmlinkage long sys_setpriority(int which, int who, int niceval) |
| 141 | { |
| 142 | struct task_struct *g, *p; |
| 143 | struct user_struct *user; |
| 144 | int error = -EINVAL; |
Eric W. Biederman | 41487c6 | 2007-02-12 00:53:01 -0800 | [diff] [blame] | 145 | struct pid *pgrp; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 146 | |
Daniel Walker | 3e88c55 | 2007-05-10 22:22:53 -0700 | [diff] [blame] | 147 | if (which > PRIO_USER || which < PRIO_PROCESS) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 148 | goto out; |
| 149 | |
| 150 | /* normalize: avoid signed division (rounding problems) */ |
| 151 | error = -ESRCH; |
| 152 | if (niceval < -20) |
| 153 | niceval = -20; |
| 154 | if (niceval > 19) |
| 155 | niceval = 19; |
| 156 | |
| 157 | read_lock(&tasklist_lock); |
| 158 | switch (which) { |
| 159 | case PRIO_PROCESS: |
Eric W. Biederman | 41487c6 | 2007-02-12 00:53:01 -0800 | [diff] [blame] | 160 | if (who) |
Pavel Emelyanov | 228ebcb | 2007-10-18 23:40:16 -0700 | [diff] [blame] | 161 | p = find_task_by_vpid(who); |
Eric W. Biederman | 41487c6 | 2007-02-12 00:53:01 -0800 | [diff] [blame] | 162 | else |
| 163 | p = current; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 164 | if (p) |
| 165 | error = set_one_prio(p, niceval, error); |
| 166 | break; |
| 167 | case PRIO_PGRP: |
Eric W. Biederman | 41487c6 | 2007-02-12 00:53:01 -0800 | [diff] [blame] | 168 | if (who) |
Pavel Emelyanov | b488893 | 2007-10-18 23:40:14 -0700 | [diff] [blame] | 169 | pgrp = find_vpid(who); |
Eric W. Biederman | 41487c6 | 2007-02-12 00:53:01 -0800 | [diff] [blame] | 170 | else |
| 171 | pgrp = task_pgrp(current); |
| 172 | do_each_pid_task(pgrp, PIDTYPE_PGID, p) { |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 173 | error = set_one_prio(p, niceval, error); |
Eric W. Biederman | 41487c6 | 2007-02-12 00:53:01 -0800 | [diff] [blame] | 174 | } while_each_pid_task(pgrp, PIDTYPE_PGID, p); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 175 | break; |
| 176 | case PRIO_USER: |
| 177 | user = current->user; |
| 178 | if (!who) |
| 179 | who = current->uid; |
| 180 | else |
| 181 | if ((who != current->uid) && !(user = find_user(who))) |
| 182 | goto out_unlock; /* No processes for this user */ |
| 183 | |
| 184 | do_each_thread(g, p) |
| 185 | if (p->uid == who) |
| 186 | error = set_one_prio(p, niceval, error); |
| 187 | while_each_thread(g, p); |
| 188 | if (who != current->uid) |
| 189 | free_uid(user); /* For find_user() */ |
| 190 | break; |
| 191 | } |
| 192 | out_unlock: |
| 193 | read_unlock(&tasklist_lock); |
| 194 | out: |
| 195 | return error; |
| 196 | } |
| 197 | |
| 198 | /* |
| 199 | * Ugh. To avoid negative return values, "getpriority()" will |
| 200 | * not return the normal nice-value, but a negated value that |
| 201 | * has been offset by 20 (ie it returns 40..1 instead of -20..19) |
| 202 | * to stay compatible. |
| 203 | */ |
| 204 | asmlinkage long sys_getpriority(int which, int who) |
| 205 | { |
| 206 | struct task_struct *g, *p; |
| 207 | struct user_struct *user; |
| 208 | long niceval, retval = -ESRCH; |
Eric W. Biederman | 41487c6 | 2007-02-12 00:53:01 -0800 | [diff] [blame] | 209 | struct pid *pgrp; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 210 | |
Daniel Walker | 3e88c55 | 2007-05-10 22:22:53 -0700 | [diff] [blame] | 211 | if (which > PRIO_USER || which < PRIO_PROCESS) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 212 | return -EINVAL; |
| 213 | |
| 214 | read_lock(&tasklist_lock); |
| 215 | switch (which) { |
| 216 | case PRIO_PROCESS: |
Eric W. Biederman | 41487c6 | 2007-02-12 00:53:01 -0800 | [diff] [blame] | 217 | if (who) |
Pavel Emelyanov | 228ebcb | 2007-10-18 23:40:16 -0700 | [diff] [blame] | 218 | p = find_task_by_vpid(who); |
Eric W. Biederman | 41487c6 | 2007-02-12 00:53:01 -0800 | [diff] [blame] | 219 | else |
| 220 | p = current; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 221 | if (p) { |
| 222 | niceval = 20 - task_nice(p); |
| 223 | if (niceval > retval) |
| 224 | retval = niceval; |
| 225 | } |
| 226 | break; |
| 227 | case PRIO_PGRP: |
Eric W. Biederman | 41487c6 | 2007-02-12 00:53:01 -0800 | [diff] [blame] | 228 | if (who) |
Pavel Emelyanov | b488893 | 2007-10-18 23:40:14 -0700 | [diff] [blame] | 229 | pgrp = find_vpid(who); |
Eric W. Biederman | 41487c6 | 2007-02-12 00:53:01 -0800 | [diff] [blame] | 230 | else |
| 231 | pgrp = task_pgrp(current); |
| 232 | do_each_pid_task(pgrp, PIDTYPE_PGID, p) { |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 233 | niceval = 20 - task_nice(p); |
| 234 | if (niceval > retval) |
| 235 | retval = niceval; |
Eric W. Biederman | 41487c6 | 2007-02-12 00:53:01 -0800 | [diff] [blame] | 236 | } while_each_pid_task(pgrp, PIDTYPE_PGID, p); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 237 | break; |
| 238 | case PRIO_USER: |
| 239 | user = current->user; |
| 240 | if (!who) |
| 241 | who = current->uid; |
| 242 | else |
| 243 | if ((who != current->uid) && !(user = find_user(who))) |
| 244 | goto out_unlock; /* No processes for this user */ |
| 245 | |
| 246 | do_each_thread(g, p) |
| 247 | if (p->uid == who) { |
| 248 | niceval = 20 - task_nice(p); |
| 249 | if (niceval > retval) |
| 250 | retval = niceval; |
| 251 | } |
| 252 | while_each_thread(g, p); |
| 253 | if (who != current->uid) |
| 254 | free_uid(user); /* for find_user() */ |
| 255 | break; |
| 256 | } |
| 257 | out_unlock: |
| 258 | read_unlock(&tasklist_lock); |
| 259 | |
| 260 | return retval; |
| 261 | } |
| 262 | |
Eric W. Biederman | e4c9433 | 2005-09-22 21:43:45 -0700 | [diff] [blame] | 263 | /** |
| 264 | * emergency_restart - reboot the system |
| 265 | * |
| 266 | * Without shutting down any hardware or taking any locks |
| 267 | * reboot the system. This is called when we know we are in |
| 268 | * trouble so this is our best effort to reboot. This is |
| 269 | * safe to call in interrupt context. |
| 270 | */ |
Eric W. Biederman | 7c90347 | 2005-07-26 11:29:55 -0600 | [diff] [blame] | 271 | void emergency_restart(void) |
| 272 | { |
| 273 | machine_emergency_restart(); |
| 274 | } |
| 275 | EXPORT_SYMBOL_GPL(emergency_restart); |
| 276 | |
Adrian Bunk | 83cc5ed | 2006-06-25 05:47:41 -0700 | [diff] [blame] | 277 | static void kernel_restart_prepare(char *cmd) |
Eric W. Biederman | 4a00ea1 | 2005-07-26 11:24:14 -0600 | [diff] [blame] | 278 | { |
Alan Stern | e041c68 | 2006-03-27 01:16:30 -0800 | [diff] [blame] | 279 | blocking_notifier_call_chain(&reboot_notifier_list, SYS_RESTART, cmd); |
Eric W. Biederman | 4a00ea1 | 2005-07-26 11:24:14 -0600 | [diff] [blame] | 280 | system_state = SYSTEM_RESTART; |
Eric W. Biederman | 4a00ea1 | 2005-07-26 11:24:14 -0600 | [diff] [blame] | 281 | device_shutdown(); |
Rafael J. Wysocki | 58b3b71 | 2007-07-26 16:29:55 +0200 | [diff] [blame] | 282 | sysdev_shutdown(); |
Eric W. Biederman | e4c9433 | 2005-09-22 21:43:45 -0700 | [diff] [blame] | 283 | } |
Randy Dunlap | 1e5d533 | 2005-11-07 01:01:06 -0800 | [diff] [blame] | 284 | |
| 285 | /** |
| 286 | * kernel_restart - reboot the system |
| 287 | * @cmd: pointer to buffer containing command to execute for restart |
Randy Dunlap | b8887e6 | 2005-11-07 01:01:07 -0800 | [diff] [blame] | 288 | * or %NULL |
Randy Dunlap | 1e5d533 | 2005-11-07 01:01:06 -0800 | [diff] [blame] | 289 | * |
| 290 | * Shutdown everything and perform a clean reboot. |
| 291 | * This is not safe to call in interrupt context. |
| 292 | */ |
Eric W. Biederman | e4c9433 | 2005-09-22 21:43:45 -0700 | [diff] [blame] | 293 | void kernel_restart(char *cmd) |
| 294 | { |
| 295 | kernel_restart_prepare(cmd); |
Cal Peake | 756184b | 2006-09-30 23:27:24 -0700 | [diff] [blame] | 296 | if (!cmd) |
Eric W. Biederman | 4a00ea1 | 2005-07-26 11:24:14 -0600 | [diff] [blame] | 297 | printk(KERN_EMERG "Restarting system.\n"); |
Cal Peake | 756184b | 2006-09-30 23:27:24 -0700 | [diff] [blame] | 298 | else |
Eric W. Biederman | 4a00ea1 | 2005-07-26 11:24:14 -0600 | [diff] [blame] | 299 | printk(KERN_EMERG "Restarting system with command '%s'.\n", cmd); |
Eric W. Biederman | 4a00ea1 | 2005-07-26 11:24:14 -0600 | [diff] [blame] | 300 | machine_restart(cmd); |
| 301 | } |
| 302 | EXPORT_SYMBOL_GPL(kernel_restart); |
| 303 | |
Adrian Bunk | 4ef7229 | 2008-02-04 22:30:06 -0800 | [diff] [blame] | 304 | static void kernel_shutdown_prepare(enum system_states state) |
Alexey Starikovskiy | 729b4d4 | 2005-12-01 04:29:00 -0500 | [diff] [blame] | 305 | { |
Alan Stern | e041c68 | 2006-03-27 01:16:30 -0800 | [diff] [blame] | 306 | blocking_notifier_call_chain(&reboot_notifier_list, |
Alexey Starikovskiy | 729b4d4 | 2005-12-01 04:29:00 -0500 | [diff] [blame] | 307 | (state == SYSTEM_HALT)?SYS_HALT:SYS_POWER_OFF, NULL); |
| 308 | system_state = state; |
| 309 | device_shutdown(); |
| 310 | } |
Eric W. Biederman | e4c9433 | 2005-09-22 21:43:45 -0700 | [diff] [blame] | 311 | /** |
| 312 | * kernel_halt - halt the system |
| 313 | * |
| 314 | * Shutdown everything and perform a clean system halt. |
| 315 | */ |
Eric W. Biederman | e4c9433 | 2005-09-22 21:43:45 -0700 | [diff] [blame] | 316 | void kernel_halt(void) |
| 317 | { |
Alexey Starikovskiy | 729b4d4 | 2005-12-01 04:29:00 -0500 | [diff] [blame] | 318 | kernel_shutdown_prepare(SYSTEM_HALT); |
Rafael J. Wysocki | 58b3b71 | 2007-07-26 16:29:55 +0200 | [diff] [blame] | 319 | sysdev_shutdown(); |
Eric W. Biederman | 4a00ea1 | 2005-07-26 11:24:14 -0600 | [diff] [blame] | 320 | printk(KERN_EMERG "System halted.\n"); |
| 321 | machine_halt(); |
| 322 | } |
Alexey Starikovskiy | 729b4d4 | 2005-12-01 04:29:00 -0500 | [diff] [blame] | 323 | |
Eric W. Biederman | 4a00ea1 | 2005-07-26 11:24:14 -0600 | [diff] [blame] | 324 | EXPORT_SYMBOL_GPL(kernel_halt); |
| 325 | |
Eric W. Biederman | e4c9433 | 2005-09-22 21:43:45 -0700 | [diff] [blame] | 326 | /** |
| 327 | * kernel_power_off - power_off the system |
| 328 | * |
| 329 | * Shutdown everything and perform a clean system power_off. |
| 330 | */ |
Eric W. Biederman | e4c9433 | 2005-09-22 21:43:45 -0700 | [diff] [blame] | 331 | void kernel_power_off(void) |
| 332 | { |
Alexey Starikovskiy | 729b4d4 | 2005-12-01 04:29:00 -0500 | [diff] [blame] | 333 | kernel_shutdown_prepare(SYSTEM_POWER_OFF); |
Rafael J. Wysocki | bd804eb | 2007-07-19 01:47:40 -0700 | [diff] [blame] | 334 | if (pm_power_off_prepare) |
| 335 | pm_power_off_prepare(); |
Mark Lord | 4047727 | 2007-10-01 01:20:10 -0700 | [diff] [blame] | 336 | disable_nonboot_cpus(); |
Rafael J. Wysocki | 58b3b71 | 2007-07-26 16:29:55 +0200 | [diff] [blame] | 337 | sysdev_shutdown(); |
Eric W. Biederman | 4a00ea1 | 2005-07-26 11:24:14 -0600 | [diff] [blame] | 338 | printk(KERN_EMERG "Power down.\n"); |
| 339 | machine_power_off(); |
| 340 | } |
| 341 | EXPORT_SYMBOL_GPL(kernel_power_off); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 342 | /* |
| 343 | * Reboot system call: for obvious reasons only root may call it, |
| 344 | * and even root needs to set up some magic numbers in the registers |
| 345 | * so that some mistake won't make this reboot the whole machine. |
| 346 | * You can also set the meaning of the ctrl-alt-del-key here. |
| 347 | * |
| 348 | * reboot doesn't sync: do that yourself before calling this. |
| 349 | */ |
| 350 | asmlinkage long sys_reboot(int magic1, int magic2, unsigned int cmd, void __user * arg) |
| 351 | { |
| 352 | char buffer[256]; |
| 353 | |
| 354 | /* We only trust the superuser with rebooting the system. */ |
| 355 | if (!capable(CAP_SYS_BOOT)) |
| 356 | return -EPERM; |
| 357 | |
| 358 | /* For safety, we require "magic" arguments. */ |
| 359 | if (magic1 != LINUX_REBOOT_MAGIC1 || |
| 360 | (magic2 != LINUX_REBOOT_MAGIC2 && |
| 361 | magic2 != LINUX_REBOOT_MAGIC2A && |
| 362 | magic2 != LINUX_REBOOT_MAGIC2B && |
| 363 | magic2 != LINUX_REBOOT_MAGIC2C)) |
| 364 | return -EINVAL; |
| 365 | |
Eric W. Biederman | 5e38291 | 2006-01-08 01:03:46 -0800 | [diff] [blame] | 366 | /* Instead of trying to make the power_off code look like |
| 367 | * halt when pm_power_off is not set do it the easy way. |
| 368 | */ |
| 369 | if ((cmd == LINUX_REBOOT_CMD_POWER_OFF) && !pm_power_off) |
| 370 | cmd = LINUX_REBOOT_CMD_HALT; |
| 371 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 372 | lock_kernel(); |
| 373 | switch (cmd) { |
| 374 | case LINUX_REBOOT_CMD_RESTART: |
Eric W. Biederman | 4a00ea1 | 2005-07-26 11:24:14 -0600 | [diff] [blame] | 375 | kernel_restart(NULL); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 376 | break; |
| 377 | |
| 378 | case LINUX_REBOOT_CMD_CAD_ON: |
| 379 | C_A_D = 1; |
| 380 | break; |
| 381 | |
| 382 | case LINUX_REBOOT_CMD_CAD_OFF: |
| 383 | C_A_D = 0; |
| 384 | break; |
| 385 | |
| 386 | case LINUX_REBOOT_CMD_HALT: |
Eric W. Biederman | 4a00ea1 | 2005-07-26 11:24:14 -0600 | [diff] [blame] | 387 | kernel_halt(); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 388 | unlock_kernel(); |
| 389 | do_exit(0); |
| 390 | break; |
| 391 | |
| 392 | case LINUX_REBOOT_CMD_POWER_OFF: |
Eric W. Biederman | 4a00ea1 | 2005-07-26 11:24:14 -0600 | [diff] [blame] | 393 | kernel_power_off(); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 394 | unlock_kernel(); |
| 395 | do_exit(0); |
| 396 | break; |
| 397 | |
| 398 | case LINUX_REBOOT_CMD_RESTART2: |
| 399 | if (strncpy_from_user(&buffer[0], arg, sizeof(buffer) - 1) < 0) { |
| 400 | unlock_kernel(); |
| 401 | return -EFAULT; |
| 402 | } |
| 403 | buffer[sizeof(buffer) - 1] = '\0'; |
| 404 | |
Eric W. Biederman | 4a00ea1 | 2005-07-26 11:24:14 -0600 | [diff] [blame] | 405 | kernel_restart(buffer); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 406 | break; |
| 407 | |
Huang Ying | 3ab8352 | 2008-07-25 19:45:07 -0700 | [diff] [blame] | 408 | #ifdef CONFIG_KEXEC |
Eric W. Biederman | dc009d9 | 2005-06-25 14:57:52 -0700 | [diff] [blame] | 409 | case LINUX_REBOOT_CMD_KEXEC: |
Huang Ying | 3ab8352 | 2008-07-25 19:45:07 -0700 | [diff] [blame] | 410 | { |
| 411 | int ret; |
| 412 | ret = kernel_kexec(); |
| 413 | unlock_kernel(); |
| 414 | return ret; |
| 415 | } |
| 416 | #endif |
Eric W. Biederman | 4a00ea1 | 2005-07-26 11:24:14 -0600 | [diff] [blame] | 417 | |
Rafael J. Wysocki | b0cb1a1 | 2007-07-29 23:24:36 +0200 | [diff] [blame] | 418 | #ifdef CONFIG_HIBERNATION |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 419 | case LINUX_REBOOT_CMD_SW_SUSPEND: |
| 420 | { |
Rafael J. Wysocki | a3d25c2 | 2007-05-09 02:33:18 -0700 | [diff] [blame] | 421 | int ret = hibernate(); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 422 | unlock_kernel(); |
| 423 | return ret; |
| 424 | } |
| 425 | #endif |
| 426 | |
| 427 | default: |
| 428 | unlock_kernel(); |
| 429 | return -EINVAL; |
| 430 | } |
| 431 | unlock_kernel(); |
| 432 | return 0; |
| 433 | } |
| 434 | |
David Howells | 65f27f3 | 2006-11-22 14:55:48 +0000 | [diff] [blame] | 435 | static void deferred_cad(struct work_struct *dummy) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 436 | { |
Eric W. Biederman | abcd9e5 | 2005-07-26 11:27:34 -0600 | [diff] [blame] | 437 | kernel_restart(NULL); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 438 | } |
| 439 | |
| 440 | /* |
| 441 | * This function gets called by ctrl-alt-del - ie the keyboard interrupt. |
| 442 | * As it's called within an interrupt, it may NOT sync: the only choice |
| 443 | * is whether to reboot at once, or just ignore the ctrl-alt-del. |
| 444 | */ |
| 445 | void ctrl_alt_del(void) |
| 446 | { |
David Howells | 65f27f3 | 2006-11-22 14:55:48 +0000 | [diff] [blame] | 447 | static DECLARE_WORK(cad_work, deferred_cad); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 448 | |
| 449 | if (C_A_D) |
| 450 | schedule_work(&cad_work); |
| 451 | else |
Cedric Le Goater | 9ec5209 | 2006-10-02 02:19:00 -0700 | [diff] [blame] | 452 | kill_cad_pid(SIGINT, 1); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 453 | } |
| 454 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 455 | /* |
| 456 | * Unprivileged users may change the real gid to the effective gid |
| 457 | * or vice versa. (BSD-style) |
| 458 | * |
| 459 | * If you set the real gid at all, or set the effective gid to a value not |
| 460 | * equal to the real gid, then the saved gid is set to the new effective gid. |
| 461 | * |
| 462 | * This makes it possible for a setgid program to completely drop its |
| 463 | * privileges, which is often a useful assertion to make when you are doing |
| 464 | * a security audit over a program. |
| 465 | * |
| 466 | * The general idea is that a program which uses just setregid() will be |
| 467 | * 100% compatible with BSD. A program which uses just setgid() will be |
| 468 | * 100% compatible with POSIX with saved IDs. |
| 469 | * |
| 470 | * SMP: There are not races, the GIDs are checked only by filesystem |
| 471 | * operations (as far as semantic preservation is concerned). |
| 472 | */ |
| 473 | asmlinkage long sys_setregid(gid_t rgid, gid_t egid) |
| 474 | { |
| 475 | int old_rgid = current->gid; |
| 476 | int old_egid = current->egid; |
| 477 | int new_rgid = old_rgid; |
| 478 | int new_egid = old_egid; |
| 479 | int retval; |
| 480 | |
| 481 | retval = security_task_setgid(rgid, egid, (gid_t)-1, LSM_SETID_RE); |
| 482 | if (retval) |
| 483 | return retval; |
| 484 | |
| 485 | if (rgid != (gid_t) -1) { |
| 486 | if ((old_rgid == rgid) || |
| 487 | (current->egid==rgid) || |
| 488 | capable(CAP_SETGID)) |
| 489 | new_rgid = rgid; |
| 490 | else |
| 491 | return -EPERM; |
| 492 | } |
| 493 | if (egid != (gid_t) -1) { |
| 494 | if ((old_rgid == egid) || |
| 495 | (current->egid == egid) || |
| 496 | (current->sgid == egid) || |
| 497 | capable(CAP_SETGID)) |
| 498 | new_egid = egid; |
Cal Peake | 756184b | 2006-09-30 23:27:24 -0700 | [diff] [blame] | 499 | else |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 500 | return -EPERM; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 501 | } |
Cal Peake | 756184b | 2006-09-30 23:27:24 -0700 | [diff] [blame] | 502 | if (new_egid != old_egid) { |
Kawai, Hidehiro | 6c5d523 | 2007-07-19 01:48:27 -0700 | [diff] [blame] | 503 | set_dumpable(current->mm, suid_dumpable); |
akpm@osdl.org | d59dd46 | 2005-05-01 08:58:47 -0700 | [diff] [blame] | 504 | smp_wmb(); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 505 | } |
| 506 | if (rgid != (gid_t) -1 || |
| 507 | (egid != (gid_t) -1 && egid != old_rgid)) |
| 508 | current->sgid = new_egid; |
| 509 | current->fsgid = new_egid; |
| 510 | current->egid = new_egid; |
| 511 | current->gid = new_rgid; |
| 512 | key_fsgid_changed(current); |
Matt Helsley | 9f46080 | 2005-11-07 00:59:16 -0800 | [diff] [blame] | 513 | proc_id_connector(current, PROC_EVENT_GID); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 514 | return 0; |
| 515 | } |
| 516 | |
| 517 | /* |
| 518 | * setgid() is implemented like SysV w/ SAVED_IDS |
| 519 | * |
| 520 | * SMP: Same implicit races as above. |
| 521 | */ |
| 522 | asmlinkage long sys_setgid(gid_t gid) |
| 523 | { |
| 524 | int old_egid = current->egid; |
| 525 | int retval; |
| 526 | |
| 527 | retval = security_task_setgid(gid, (gid_t)-1, (gid_t)-1, LSM_SETID_ID); |
| 528 | if (retval) |
| 529 | return retval; |
| 530 | |
Cal Peake | 756184b | 2006-09-30 23:27:24 -0700 | [diff] [blame] | 531 | if (capable(CAP_SETGID)) { |
| 532 | if (old_egid != gid) { |
Kawai, Hidehiro | 6c5d523 | 2007-07-19 01:48:27 -0700 | [diff] [blame] | 533 | set_dumpable(current->mm, suid_dumpable); |
akpm@osdl.org | d59dd46 | 2005-05-01 08:58:47 -0700 | [diff] [blame] | 534 | smp_wmb(); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 535 | } |
| 536 | current->gid = current->egid = current->sgid = current->fsgid = gid; |
Cal Peake | 756184b | 2006-09-30 23:27:24 -0700 | [diff] [blame] | 537 | } else if ((gid == current->gid) || (gid == current->sgid)) { |
| 538 | if (old_egid != gid) { |
Kawai, Hidehiro | 6c5d523 | 2007-07-19 01:48:27 -0700 | [diff] [blame] | 539 | set_dumpable(current->mm, suid_dumpable); |
akpm@osdl.org | d59dd46 | 2005-05-01 08:58:47 -0700 | [diff] [blame] | 540 | smp_wmb(); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 541 | } |
| 542 | current->egid = current->fsgid = gid; |
| 543 | } |
| 544 | else |
| 545 | return -EPERM; |
| 546 | |
| 547 | key_fsgid_changed(current); |
Matt Helsley | 9f46080 | 2005-11-07 00:59:16 -0800 | [diff] [blame] | 548 | proc_id_connector(current, PROC_EVENT_GID); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 549 | return 0; |
| 550 | } |
| 551 | |
| 552 | static int set_user(uid_t new_ruid, int dumpclear) |
| 553 | { |
| 554 | struct user_struct *new_user; |
| 555 | |
Cedric Le Goater | acce292 | 2007-07-15 23:40:59 -0700 | [diff] [blame] | 556 | new_user = alloc_uid(current->nsproxy->user_ns, new_ruid); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 557 | if (!new_user) |
| 558 | return -EAGAIN; |
| 559 | |
| 560 | if (atomic_read(&new_user->processes) >= |
| 561 | current->signal->rlim[RLIMIT_NPROC].rlim_cur && |
Cedric Le Goater | acce292 | 2007-07-15 23:40:59 -0700 | [diff] [blame] | 562 | new_user != current->nsproxy->user_ns->root_user) { |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 563 | free_uid(new_user); |
| 564 | return -EAGAIN; |
| 565 | } |
| 566 | |
| 567 | switch_uid(new_user); |
| 568 | |
Cal Peake | 756184b | 2006-09-30 23:27:24 -0700 | [diff] [blame] | 569 | if (dumpclear) { |
Kawai, Hidehiro | 6c5d523 | 2007-07-19 01:48:27 -0700 | [diff] [blame] | 570 | set_dumpable(current->mm, suid_dumpable); |
akpm@osdl.org | d59dd46 | 2005-05-01 08:58:47 -0700 | [diff] [blame] | 571 | smp_wmb(); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 572 | } |
| 573 | current->uid = new_ruid; |
| 574 | return 0; |
| 575 | } |
| 576 | |
| 577 | /* |
| 578 | * Unprivileged users may change the real uid to the effective uid |
| 579 | * or vice versa. (BSD-style) |
| 580 | * |
| 581 | * If you set the real uid at all, or set the effective uid to a value not |
| 582 | * equal to the real uid, then the saved uid is set to the new effective uid. |
| 583 | * |
| 584 | * This makes it possible for a setuid program to completely drop its |
| 585 | * privileges, which is often a useful assertion to make when you are doing |
| 586 | * a security audit over a program. |
| 587 | * |
| 588 | * The general idea is that a program which uses just setreuid() will be |
| 589 | * 100% compatible with BSD. A program which uses just setuid() will be |
| 590 | * 100% compatible with POSIX with saved IDs. |
| 591 | */ |
| 592 | asmlinkage long sys_setreuid(uid_t ruid, uid_t euid) |
| 593 | { |
| 594 | int old_ruid, old_euid, old_suid, new_ruid, new_euid; |
| 595 | int retval; |
| 596 | |
| 597 | retval = security_task_setuid(ruid, euid, (uid_t)-1, LSM_SETID_RE); |
| 598 | if (retval) |
| 599 | return retval; |
| 600 | |
| 601 | new_ruid = old_ruid = current->uid; |
| 602 | new_euid = old_euid = current->euid; |
| 603 | old_suid = current->suid; |
| 604 | |
| 605 | if (ruid != (uid_t) -1) { |
| 606 | new_ruid = ruid; |
| 607 | if ((old_ruid != ruid) && |
| 608 | (current->euid != ruid) && |
| 609 | !capable(CAP_SETUID)) |
| 610 | return -EPERM; |
| 611 | } |
| 612 | |
| 613 | if (euid != (uid_t) -1) { |
| 614 | new_euid = euid; |
| 615 | if ((old_ruid != euid) && |
| 616 | (current->euid != euid) && |
| 617 | (current->suid != euid) && |
| 618 | !capable(CAP_SETUID)) |
| 619 | return -EPERM; |
| 620 | } |
| 621 | |
| 622 | if (new_ruid != old_ruid && set_user(new_ruid, new_euid != old_euid) < 0) |
| 623 | return -EAGAIN; |
| 624 | |
Cal Peake | 756184b | 2006-09-30 23:27:24 -0700 | [diff] [blame] | 625 | if (new_euid != old_euid) { |
Kawai, Hidehiro | 6c5d523 | 2007-07-19 01:48:27 -0700 | [diff] [blame] | 626 | set_dumpable(current->mm, suid_dumpable); |
akpm@osdl.org | d59dd46 | 2005-05-01 08:58:47 -0700 | [diff] [blame] | 627 | smp_wmb(); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 628 | } |
| 629 | current->fsuid = current->euid = new_euid; |
| 630 | if (ruid != (uid_t) -1 || |
| 631 | (euid != (uid_t) -1 && euid != old_ruid)) |
| 632 | current->suid = current->euid; |
| 633 | current->fsuid = current->euid; |
| 634 | |
| 635 | key_fsuid_changed(current); |
Matt Helsley | 9f46080 | 2005-11-07 00:59:16 -0800 | [diff] [blame] | 636 | proc_id_connector(current, PROC_EVENT_UID); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 637 | |
| 638 | return security_task_post_setuid(old_ruid, old_euid, old_suid, LSM_SETID_RE); |
| 639 | } |
| 640 | |
| 641 | |
| 642 | |
| 643 | /* |
| 644 | * setuid() is implemented like SysV with SAVED_IDS |
| 645 | * |
| 646 | * Note that SAVED_ID's is deficient in that a setuid root program |
| 647 | * like sendmail, for example, cannot set its uid to be a normal |
| 648 | * user and then switch back, because if you're root, setuid() sets |
| 649 | * the saved uid too. If you don't like this, blame the bright people |
| 650 | * in the POSIX committee and/or USG. Note that the BSD-style setreuid() |
| 651 | * will allow a root program to temporarily drop privileges and be able to |
| 652 | * regain them by swapping the real and effective uid. |
| 653 | */ |
| 654 | asmlinkage long sys_setuid(uid_t uid) |
| 655 | { |
| 656 | int old_euid = current->euid; |
David Rientjes | a09c17a | 2006-12-06 20:40:18 -0800 | [diff] [blame] | 657 | int old_ruid, old_suid, new_suid; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 658 | int retval; |
| 659 | |
| 660 | retval = security_task_setuid(uid, (uid_t)-1, (uid_t)-1, LSM_SETID_ID); |
| 661 | if (retval) |
| 662 | return retval; |
| 663 | |
David Rientjes | a09c17a | 2006-12-06 20:40:18 -0800 | [diff] [blame] | 664 | old_ruid = current->uid; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 665 | old_suid = current->suid; |
| 666 | new_suid = old_suid; |
| 667 | |
| 668 | if (capable(CAP_SETUID)) { |
| 669 | if (uid != old_ruid && set_user(uid, old_euid != uid) < 0) |
| 670 | return -EAGAIN; |
| 671 | new_suid = uid; |
| 672 | } else if ((uid != current->uid) && (uid != new_suid)) |
| 673 | return -EPERM; |
| 674 | |
Cal Peake | 756184b | 2006-09-30 23:27:24 -0700 | [diff] [blame] | 675 | if (old_euid != uid) { |
Kawai, Hidehiro | 6c5d523 | 2007-07-19 01:48:27 -0700 | [diff] [blame] | 676 | set_dumpable(current->mm, suid_dumpable); |
akpm@osdl.org | d59dd46 | 2005-05-01 08:58:47 -0700 | [diff] [blame] | 677 | smp_wmb(); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 678 | } |
| 679 | current->fsuid = current->euid = uid; |
| 680 | current->suid = new_suid; |
| 681 | |
| 682 | key_fsuid_changed(current); |
Matt Helsley | 9f46080 | 2005-11-07 00:59:16 -0800 | [diff] [blame] | 683 | proc_id_connector(current, PROC_EVENT_UID); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 684 | |
| 685 | return security_task_post_setuid(old_ruid, old_euid, old_suid, LSM_SETID_ID); |
| 686 | } |
| 687 | |
| 688 | |
| 689 | /* |
| 690 | * This function implements a generic ability to update ruid, euid, |
| 691 | * and suid. This allows you to implement the 4.4 compatible seteuid(). |
| 692 | */ |
| 693 | asmlinkage long sys_setresuid(uid_t ruid, uid_t euid, uid_t suid) |
| 694 | { |
| 695 | int old_ruid = current->uid; |
| 696 | int old_euid = current->euid; |
| 697 | int old_suid = current->suid; |
| 698 | int retval; |
| 699 | |
| 700 | retval = security_task_setuid(ruid, euid, suid, LSM_SETID_RES); |
| 701 | if (retval) |
| 702 | return retval; |
| 703 | |
| 704 | if (!capable(CAP_SETUID)) { |
| 705 | if ((ruid != (uid_t) -1) && (ruid != current->uid) && |
| 706 | (ruid != current->euid) && (ruid != current->suid)) |
| 707 | return -EPERM; |
| 708 | if ((euid != (uid_t) -1) && (euid != current->uid) && |
| 709 | (euid != current->euid) && (euid != current->suid)) |
| 710 | return -EPERM; |
| 711 | if ((suid != (uid_t) -1) && (suid != current->uid) && |
| 712 | (suid != current->euid) && (suid != current->suid)) |
| 713 | return -EPERM; |
| 714 | } |
| 715 | if (ruid != (uid_t) -1) { |
| 716 | if (ruid != current->uid && set_user(ruid, euid != current->euid) < 0) |
| 717 | return -EAGAIN; |
| 718 | } |
| 719 | if (euid != (uid_t) -1) { |
Cal Peake | 756184b | 2006-09-30 23:27:24 -0700 | [diff] [blame] | 720 | if (euid != current->euid) { |
Kawai, Hidehiro | 6c5d523 | 2007-07-19 01:48:27 -0700 | [diff] [blame] | 721 | set_dumpable(current->mm, suid_dumpable); |
akpm@osdl.org | d59dd46 | 2005-05-01 08:58:47 -0700 | [diff] [blame] | 722 | smp_wmb(); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 723 | } |
| 724 | current->euid = euid; |
| 725 | } |
| 726 | current->fsuid = current->euid; |
| 727 | if (suid != (uid_t) -1) |
| 728 | current->suid = suid; |
| 729 | |
| 730 | key_fsuid_changed(current); |
Matt Helsley | 9f46080 | 2005-11-07 00:59:16 -0800 | [diff] [blame] | 731 | proc_id_connector(current, PROC_EVENT_UID); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 732 | |
| 733 | return security_task_post_setuid(old_ruid, old_euid, old_suid, LSM_SETID_RES); |
| 734 | } |
| 735 | |
| 736 | asmlinkage long sys_getresuid(uid_t __user *ruid, uid_t __user *euid, uid_t __user *suid) |
| 737 | { |
| 738 | int retval; |
| 739 | |
| 740 | if (!(retval = put_user(current->uid, ruid)) && |
| 741 | !(retval = put_user(current->euid, euid))) |
| 742 | retval = put_user(current->suid, suid); |
| 743 | |
| 744 | return retval; |
| 745 | } |
| 746 | |
| 747 | /* |
| 748 | * Same as above, but for rgid, egid, sgid. |
| 749 | */ |
| 750 | asmlinkage long sys_setresgid(gid_t rgid, gid_t egid, gid_t sgid) |
| 751 | { |
| 752 | int retval; |
| 753 | |
| 754 | retval = security_task_setgid(rgid, egid, sgid, LSM_SETID_RES); |
| 755 | if (retval) |
| 756 | return retval; |
| 757 | |
| 758 | if (!capable(CAP_SETGID)) { |
| 759 | if ((rgid != (gid_t) -1) && (rgid != current->gid) && |
| 760 | (rgid != current->egid) && (rgid != current->sgid)) |
| 761 | return -EPERM; |
| 762 | if ((egid != (gid_t) -1) && (egid != current->gid) && |
| 763 | (egid != current->egid) && (egid != current->sgid)) |
| 764 | return -EPERM; |
| 765 | if ((sgid != (gid_t) -1) && (sgid != current->gid) && |
| 766 | (sgid != current->egid) && (sgid != current->sgid)) |
| 767 | return -EPERM; |
| 768 | } |
| 769 | if (egid != (gid_t) -1) { |
Cal Peake | 756184b | 2006-09-30 23:27:24 -0700 | [diff] [blame] | 770 | if (egid != current->egid) { |
Kawai, Hidehiro | 6c5d523 | 2007-07-19 01:48:27 -0700 | [diff] [blame] | 771 | set_dumpable(current->mm, suid_dumpable); |
akpm@osdl.org | d59dd46 | 2005-05-01 08:58:47 -0700 | [diff] [blame] | 772 | smp_wmb(); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 773 | } |
| 774 | current->egid = egid; |
| 775 | } |
| 776 | current->fsgid = current->egid; |
| 777 | if (rgid != (gid_t) -1) |
| 778 | current->gid = rgid; |
| 779 | if (sgid != (gid_t) -1) |
| 780 | current->sgid = sgid; |
| 781 | |
| 782 | key_fsgid_changed(current); |
Matt Helsley | 9f46080 | 2005-11-07 00:59:16 -0800 | [diff] [blame] | 783 | proc_id_connector(current, PROC_EVENT_GID); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 784 | return 0; |
| 785 | } |
| 786 | |
| 787 | asmlinkage long sys_getresgid(gid_t __user *rgid, gid_t __user *egid, gid_t __user *sgid) |
| 788 | { |
| 789 | int retval; |
| 790 | |
| 791 | if (!(retval = put_user(current->gid, rgid)) && |
| 792 | !(retval = put_user(current->egid, egid))) |
| 793 | retval = put_user(current->sgid, sgid); |
| 794 | |
| 795 | return retval; |
| 796 | } |
| 797 | |
| 798 | |
| 799 | /* |
| 800 | * "setfsuid()" sets the fsuid - the uid used for filesystem checks. This |
| 801 | * is used for "access()" and for the NFS daemon (letting nfsd stay at |
| 802 | * whatever uid it wants to). It normally shadows "euid", except when |
| 803 | * explicitly set by setfsuid() or for access.. |
| 804 | */ |
| 805 | asmlinkage long sys_setfsuid(uid_t uid) |
| 806 | { |
| 807 | int old_fsuid; |
| 808 | |
| 809 | old_fsuid = current->fsuid; |
| 810 | if (security_task_setuid(uid, (uid_t)-1, (uid_t)-1, LSM_SETID_FS)) |
| 811 | return old_fsuid; |
| 812 | |
| 813 | if (uid == current->uid || uid == current->euid || |
| 814 | uid == current->suid || uid == current->fsuid || |
Cal Peake | 756184b | 2006-09-30 23:27:24 -0700 | [diff] [blame] | 815 | capable(CAP_SETUID)) { |
| 816 | if (uid != old_fsuid) { |
Kawai, Hidehiro | 6c5d523 | 2007-07-19 01:48:27 -0700 | [diff] [blame] | 817 | set_dumpable(current->mm, suid_dumpable); |
akpm@osdl.org | d59dd46 | 2005-05-01 08:58:47 -0700 | [diff] [blame] | 818 | smp_wmb(); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 819 | } |
| 820 | current->fsuid = uid; |
| 821 | } |
| 822 | |
| 823 | key_fsuid_changed(current); |
Matt Helsley | 9f46080 | 2005-11-07 00:59:16 -0800 | [diff] [blame] | 824 | proc_id_connector(current, PROC_EVENT_UID); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 825 | |
| 826 | security_task_post_setuid(old_fsuid, (uid_t)-1, (uid_t)-1, LSM_SETID_FS); |
| 827 | |
| 828 | return old_fsuid; |
| 829 | } |
| 830 | |
| 831 | /* |
John Anthony Kazos Jr | f42df9e | 2007-05-09 08:23:08 +0200 | [diff] [blame] | 832 | * Samma på svenska.. |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 833 | */ |
| 834 | asmlinkage long sys_setfsgid(gid_t gid) |
| 835 | { |
| 836 | int old_fsgid; |
| 837 | |
| 838 | old_fsgid = current->fsgid; |
| 839 | if (security_task_setgid(gid, (gid_t)-1, (gid_t)-1, LSM_SETID_FS)) |
| 840 | return old_fsgid; |
| 841 | |
| 842 | if (gid == current->gid || gid == current->egid || |
| 843 | gid == current->sgid || gid == current->fsgid || |
Cal Peake | 756184b | 2006-09-30 23:27:24 -0700 | [diff] [blame] | 844 | capable(CAP_SETGID)) { |
| 845 | if (gid != old_fsgid) { |
Kawai, Hidehiro | 6c5d523 | 2007-07-19 01:48:27 -0700 | [diff] [blame] | 846 | set_dumpable(current->mm, suid_dumpable); |
akpm@osdl.org | d59dd46 | 2005-05-01 08:58:47 -0700 | [diff] [blame] | 847 | smp_wmb(); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 848 | } |
| 849 | current->fsgid = gid; |
| 850 | key_fsgid_changed(current); |
Matt Helsley | 9f46080 | 2005-11-07 00:59:16 -0800 | [diff] [blame] | 851 | proc_id_connector(current, PROC_EVENT_GID); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 852 | } |
| 853 | return old_fsgid; |
| 854 | } |
| 855 | |
| 856 | asmlinkage long sys_times(struct tms __user * tbuf) |
| 857 | { |
| 858 | /* |
| 859 | * In the SMP world we might just be unlucky and have one of |
| 860 | * the times increment as we use it. Since the value is an |
| 861 | * atomically safe type this is just fine. Conceptually its |
| 862 | * as if the syscall took an instant longer to occur. |
| 863 | */ |
| 864 | if (tbuf) { |
| 865 | struct tms tmp; |
Oleg Nesterov | 35f5cad | 2006-03-28 16:11:19 -0800 | [diff] [blame] | 866 | struct task_struct *tsk = current; |
| 867 | struct task_struct *t; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 868 | cputime_t utime, stime, cutime, cstime; |
| 869 | |
Oleg Nesterov | 7d7185c | 2006-03-28 16:11:21 -0800 | [diff] [blame] | 870 | spin_lock_irq(&tsk->sighand->siglock); |
Oleg Nesterov | 35f5cad | 2006-03-28 16:11:19 -0800 | [diff] [blame] | 871 | utime = tsk->signal->utime; |
| 872 | stime = tsk->signal->stime; |
| 873 | t = tsk; |
| 874 | do { |
| 875 | utime = cputime_add(utime, t->utime); |
| 876 | stime = cputime_add(stime, t->stime); |
| 877 | t = next_thread(t); |
| 878 | } while (t != tsk); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 879 | |
Oleg Nesterov | 35f5cad | 2006-03-28 16:11:19 -0800 | [diff] [blame] | 880 | cutime = tsk->signal->cutime; |
| 881 | cstime = tsk->signal->cstime; |
| 882 | spin_unlock_irq(&tsk->sighand->siglock); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 883 | |
| 884 | tmp.tms_utime = cputime_to_clock_t(utime); |
| 885 | tmp.tms_stime = cputime_to_clock_t(stime); |
| 886 | tmp.tms_cutime = cputime_to_clock_t(cutime); |
| 887 | tmp.tms_cstime = cputime_to_clock_t(cstime); |
| 888 | if (copy_to_user(tbuf, &tmp, sizeof(struct tms))) |
| 889 | return -EFAULT; |
| 890 | } |
| 891 | return (long) jiffies_64_to_clock_t(get_jiffies_64()); |
| 892 | } |
| 893 | |
| 894 | /* |
| 895 | * This needs some heavy checking ... |
| 896 | * I just haven't the stomach for it. I also don't fully |
| 897 | * understand sessions/pgrp etc. Let somebody who does explain it. |
| 898 | * |
| 899 | * OK, I think I have the protection semantics right.... this is really |
| 900 | * only important on a multi-user system anyway, to make sure one user |
| 901 | * can't send a signal to a process owned by another. -TYT, 12/12/91 |
| 902 | * |
| 903 | * Auch. Had to add the 'did_exec' flag to conform completely to POSIX. |
| 904 | * LBT 04.03.94 |
| 905 | */ |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 906 | asmlinkage long sys_setpgid(pid_t pid, pid_t pgid) |
| 907 | { |
| 908 | struct task_struct *p; |
Oleg Nesterov | ee0acf9 | 2006-01-08 01:03:53 -0800 | [diff] [blame] | 909 | struct task_struct *group_leader = current->group_leader; |
Oleg Nesterov | 4e02130 | 2008-02-08 04:19:08 -0800 | [diff] [blame] | 910 | struct pid *pgrp; |
| 911 | int err; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 912 | |
| 913 | if (!pid) |
Pavel Emelyanov | b488893 | 2007-10-18 23:40:14 -0700 | [diff] [blame] | 914 | pid = task_pid_vnr(group_leader); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 915 | if (!pgid) |
| 916 | pgid = pid; |
| 917 | if (pgid < 0) |
| 918 | return -EINVAL; |
| 919 | |
| 920 | /* From this point forward we keep holding onto the tasklist lock |
| 921 | * so that our parent does not change from under us. -DaveM |
| 922 | */ |
| 923 | write_lock_irq(&tasklist_lock); |
| 924 | |
| 925 | err = -ESRCH; |
Oleg Nesterov | 4e02130 | 2008-02-08 04:19:08 -0800 | [diff] [blame] | 926 | p = find_task_by_vpid(pid); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 927 | if (!p) |
| 928 | goto out; |
| 929 | |
| 930 | err = -EINVAL; |
| 931 | if (!thread_group_leader(p)) |
| 932 | goto out; |
| 933 | |
Oleg Nesterov | 4e02130 | 2008-02-08 04:19:08 -0800 | [diff] [blame] | 934 | if (same_thread_group(p->real_parent, group_leader)) { |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 935 | err = -EPERM; |
Eric W. Biederman | 41487c6 | 2007-02-12 00:53:01 -0800 | [diff] [blame] | 936 | if (task_session(p) != task_session(group_leader)) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 937 | goto out; |
| 938 | err = -EACCES; |
| 939 | if (p->did_exec) |
| 940 | goto out; |
| 941 | } else { |
| 942 | err = -ESRCH; |
Oleg Nesterov | ee0acf9 | 2006-01-08 01:03:53 -0800 | [diff] [blame] | 943 | if (p != group_leader) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 944 | goto out; |
| 945 | } |
| 946 | |
| 947 | err = -EPERM; |
| 948 | if (p->signal->leader) |
| 949 | goto out; |
| 950 | |
Oleg Nesterov | 4e02130 | 2008-02-08 04:19:08 -0800 | [diff] [blame] | 951 | pgrp = task_pid(p); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 952 | if (pgid != pid) { |
Pavel Emelyanov | b488893 | 2007-10-18 23:40:14 -0700 | [diff] [blame] | 953 | struct task_struct *g; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 954 | |
Oleg Nesterov | 4e02130 | 2008-02-08 04:19:08 -0800 | [diff] [blame] | 955 | pgrp = find_vpid(pgid); |
| 956 | g = pid_task(pgrp, PIDTYPE_PGID); |
Eric W. Biederman | 41487c6 | 2007-02-12 00:53:01 -0800 | [diff] [blame] | 957 | if (!g || task_session(g) != task_session(group_leader)) |
Oleg Nesterov | f020bc4 | 2006-12-08 02:38:02 -0800 | [diff] [blame] | 958 | goto out; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 959 | } |
| 960 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 961 | err = security_task_setpgid(p, pgid); |
| 962 | if (err) |
| 963 | goto out; |
| 964 | |
Oleg Nesterov | 4e02130 | 2008-02-08 04:19:08 -0800 | [diff] [blame] | 965 | if (task_pgrp(p) != pgrp) { |
Oleg Nesterov | 83beaf3 | 2008-04-30 00:54:27 -0700 | [diff] [blame] | 966 | change_pid(p, PIDTYPE_PGID, pgrp); |
Oleg Nesterov | 4e02130 | 2008-02-08 04:19:08 -0800 | [diff] [blame] | 967 | set_task_pgrp(p, pid_nr(pgrp)); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 968 | } |
| 969 | |
| 970 | err = 0; |
| 971 | out: |
| 972 | /* All paths lead to here, thus we are safe. -DaveM */ |
| 973 | write_unlock_irq(&tasklist_lock); |
| 974 | return err; |
| 975 | } |
| 976 | |
| 977 | asmlinkage long sys_getpgid(pid_t pid) |
| 978 | { |
Oleg Nesterov | 12a3de0a | 2008-04-30 00:54:29 -0700 | [diff] [blame] | 979 | struct task_struct *p; |
| 980 | struct pid *grp; |
| 981 | int retval; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 982 | |
Oleg Nesterov | 12a3de0a | 2008-04-30 00:54:29 -0700 | [diff] [blame] | 983 | rcu_read_lock(); |
| 984 | if (!pid) |
| 985 | grp = task_pgrp(current); |
| 986 | else { |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 987 | retval = -ESRCH; |
Oleg Nesterov | 12a3de0a | 2008-04-30 00:54:29 -0700 | [diff] [blame] | 988 | p = find_task_by_vpid(pid); |
| 989 | if (!p) |
| 990 | goto out; |
| 991 | grp = task_pgrp(p); |
| 992 | if (!grp) |
| 993 | goto out; |
| 994 | |
| 995 | retval = security_task_getpgid(p); |
| 996 | if (retval) |
| 997 | goto out; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 998 | } |
Oleg Nesterov | 12a3de0a | 2008-04-30 00:54:29 -0700 | [diff] [blame] | 999 | retval = pid_vnr(grp); |
| 1000 | out: |
| 1001 | rcu_read_unlock(); |
| 1002 | return retval; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1003 | } |
| 1004 | |
| 1005 | #ifdef __ARCH_WANT_SYS_GETPGRP |
| 1006 | |
| 1007 | asmlinkage long sys_getpgrp(void) |
| 1008 | { |
Oleg Nesterov | 12a3de0a | 2008-04-30 00:54:29 -0700 | [diff] [blame] | 1009 | return sys_getpgid(0); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1010 | } |
| 1011 | |
| 1012 | #endif |
| 1013 | |
| 1014 | asmlinkage long sys_getsid(pid_t pid) |
| 1015 | { |
Oleg Nesterov | 1dd768c0 | 2008-04-30 00:54:28 -0700 | [diff] [blame] | 1016 | struct task_struct *p; |
| 1017 | struct pid *sid; |
| 1018 | int retval; |
Pavel Emelyanov | b488893 | 2007-10-18 23:40:14 -0700 | [diff] [blame] | 1019 | |
Oleg Nesterov | 1dd768c0 | 2008-04-30 00:54:28 -0700 | [diff] [blame] | 1020 | rcu_read_lock(); |
| 1021 | if (!pid) |
| 1022 | sid = task_session(current); |
| 1023 | else { |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1024 | retval = -ESRCH; |
Oleg Nesterov | 1dd768c0 | 2008-04-30 00:54:28 -0700 | [diff] [blame] | 1025 | p = find_task_by_vpid(pid); |
| 1026 | if (!p) |
| 1027 | goto out; |
| 1028 | sid = task_session(p); |
| 1029 | if (!sid) |
| 1030 | goto out; |
| 1031 | |
| 1032 | retval = security_task_getsid(p); |
| 1033 | if (retval) |
| 1034 | goto out; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1035 | } |
Oleg Nesterov | 1dd768c0 | 2008-04-30 00:54:28 -0700 | [diff] [blame] | 1036 | retval = pid_vnr(sid); |
| 1037 | out: |
| 1038 | rcu_read_unlock(); |
| 1039 | return retval; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1040 | } |
| 1041 | |
| 1042 | asmlinkage long sys_setsid(void) |
| 1043 | { |
Oren Laadan | e19f247 | 2006-01-08 01:03:58 -0800 | [diff] [blame] | 1044 | struct task_struct *group_leader = current->group_leader; |
Oleg Nesterov | e4cc0a9 | 2008-02-08 04:19:09 -0800 | [diff] [blame] | 1045 | struct pid *sid = task_pid(group_leader); |
| 1046 | pid_t session = pid_vnr(sid); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1047 | int err = -EPERM; |
| 1048 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1049 | write_lock_irq(&tasklist_lock); |
Eric W. Biederman | 390e2ff | 2006-03-31 02:31:33 -0800 | [diff] [blame] | 1050 | /* Fail if I am already a session leader */ |
| 1051 | if (group_leader->signal->leader) |
| 1052 | goto out; |
| 1053 | |
Oleg Nesterov | 430c623 | 2008-02-08 04:19:11 -0800 | [diff] [blame] | 1054 | /* Fail if a process group id already exists that equals the |
| 1055 | * proposed session id. |
Eric W. Biederman | 390e2ff | 2006-03-31 02:31:33 -0800 | [diff] [blame] | 1056 | */ |
Oleg Nesterov | 6806aac | 2008-02-08 04:19:12 -0800 | [diff] [blame] | 1057 | if (pid_task(sid, PIDTYPE_PGID)) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1058 | goto out; |
| 1059 | |
Oren Laadan | e19f247 | 2006-01-08 01:03:58 -0800 | [diff] [blame] | 1060 | group_leader->signal->leader = 1; |
Oleg Nesterov | 8520d7c | 2008-02-08 04:19:09 -0800 | [diff] [blame] | 1061 | __set_special_pids(sid); |
Peter Zijlstra | 24ec839 | 2006-12-08 02:36:04 -0800 | [diff] [blame] | 1062 | |
| 1063 | spin_lock(&group_leader->sighand->siglock); |
Oren Laadan | e19f247 | 2006-01-08 01:03:58 -0800 | [diff] [blame] | 1064 | group_leader->signal->tty = NULL; |
Peter Zijlstra | 24ec839 | 2006-12-08 02:36:04 -0800 | [diff] [blame] | 1065 | spin_unlock(&group_leader->sighand->siglock); |
| 1066 | |
Oleg Nesterov | e4cc0a9 | 2008-02-08 04:19:09 -0800 | [diff] [blame] | 1067 | err = session; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1068 | out: |
| 1069 | write_unlock_irq(&tasklist_lock); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1070 | return err; |
| 1071 | } |
| 1072 | |
| 1073 | /* |
| 1074 | * Supplementary group IDs |
| 1075 | */ |
| 1076 | |
| 1077 | /* init to 2 - one for init_task, one to ensure it is never freed */ |
| 1078 | struct group_info init_groups = { .usage = ATOMIC_INIT(2) }; |
| 1079 | |
| 1080 | struct group_info *groups_alloc(int gidsetsize) |
| 1081 | { |
| 1082 | struct group_info *group_info; |
| 1083 | int nblocks; |
| 1084 | int i; |
| 1085 | |
| 1086 | nblocks = (gidsetsize + NGROUPS_PER_BLOCK - 1) / NGROUPS_PER_BLOCK; |
| 1087 | /* Make sure we always allocate at least one indirect block pointer */ |
| 1088 | nblocks = nblocks ? : 1; |
| 1089 | group_info = kmalloc(sizeof(*group_info) + nblocks*sizeof(gid_t *), GFP_USER); |
| 1090 | if (!group_info) |
| 1091 | return NULL; |
| 1092 | group_info->ngroups = gidsetsize; |
| 1093 | group_info->nblocks = nblocks; |
| 1094 | atomic_set(&group_info->usage, 1); |
| 1095 | |
Cal Peake | 756184b | 2006-09-30 23:27:24 -0700 | [diff] [blame] | 1096 | if (gidsetsize <= NGROUPS_SMALL) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1097 | group_info->blocks[0] = group_info->small_block; |
Cal Peake | 756184b | 2006-09-30 23:27:24 -0700 | [diff] [blame] | 1098 | else { |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1099 | for (i = 0; i < nblocks; i++) { |
| 1100 | gid_t *b; |
| 1101 | b = (void *)__get_free_page(GFP_USER); |
| 1102 | if (!b) |
| 1103 | goto out_undo_partial_alloc; |
| 1104 | group_info->blocks[i] = b; |
| 1105 | } |
| 1106 | } |
| 1107 | return group_info; |
| 1108 | |
| 1109 | out_undo_partial_alloc: |
| 1110 | while (--i >= 0) { |
| 1111 | free_page((unsigned long)group_info->blocks[i]); |
| 1112 | } |
| 1113 | kfree(group_info); |
| 1114 | return NULL; |
| 1115 | } |
| 1116 | |
| 1117 | EXPORT_SYMBOL(groups_alloc); |
| 1118 | |
| 1119 | void groups_free(struct group_info *group_info) |
| 1120 | { |
| 1121 | if (group_info->blocks[0] != group_info->small_block) { |
| 1122 | int i; |
| 1123 | for (i = 0; i < group_info->nblocks; i++) |
| 1124 | free_page((unsigned long)group_info->blocks[i]); |
| 1125 | } |
| 1126 | kfree(group_info); |
| 1127 | } |
| 1128 | |
| 1129 | EXPORT_SYMBOL(groups_free); |
| 1130 | |
| 1131 | /* export the group_info to a user-space array */ |
| 1132 | static int groups_to_user(gid_t __user *grouplist, |
| 1133 | struct group_info *group_info) |
| 1134 | { |
| 1135 | int i; |
Eric Dumazet | 1bf4734 | 2008-02-06 01:37:56 -0800 | [diff] [blame] | 1136 | unsigned int count = group_info->ngroups; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1137 | |
| 1138 | for (i = 0; i < group_info->nblocks; i++) { |
Eric Dumazet | 1bf4734 | 2008-02-06 01:37:56 -0800 | [diff] [blame] | 1139 | unsigned int cp_count = min(NGROUPS_PER_BLOCK, count); |
| 1140 | unsigned int len = cp_count * sizeof(*grouplist); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1141 | |
Eric Dumazet | 1bf4734 | 2008-02-06 01:37:56 -0800 | [diff] [blame] | 1142 | if (copy_to_user(grouplist, group_info->blocks[i], len)) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1143 | return -EFAULT; |
| 1144 | |
Eric Dumazet | 1bf4734 | 2008-02-06 01:37:56 -0800 | [diff] [blame] | 1145 | grouplist += NGROUPS_PER_BLOCK; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1146 | count -= cp_count; |
| 1147 | } |
| 1148 | return 0; |
| 1149 | } |
| 1150 | |
| 1151 | /* fill a group_info from a user-space array - it must be allocated already */ |
| 1152 | static int groups_from_user(struct group_info *group_info, |
| 1153 | gid_t __user *grouplist) |
Cal Peake | 756184b | 2006-09-30 23:27:24 -0700 | [diff] [blame] | 1154 | { |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1155 | int i; |
Eric Dumazet | 1bf4734 | 2008-02-06 01:37:56 -0800 | [diff] [blame] | 1156 | unsigned int count = group_info->ngroups; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1157 | |
| 1158 | for (i = 0; i < group_info->nblocks; i++) { |
Eric Dumazet | 1bf4734 | 2008-02-06 01:37:56 -0800 | [diff] [blame] | 1159 | unsigned int cp_count = min(NGROUPS_PER_BLOCK, count); |
| 1160 | unsigned int len = cp_count * sizeof(*grouplist); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1161 | |
Eric Dumazet | 1bf4734 | 2008-02-06 01:37:56 -0800 | [diff] [blame] | 1162 | if (copy_from_user(group_info->blocks[i], grouplist, len)) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1163 | return -EFAULT; |
| 1164 | |
Eric Dumazet | 1bf4734 | 2008-02-06 01:37:56 -0800 | [diff] [blame] | 1165 | grouplist += NGROUPS_PER_BLOCK; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1166 | count -= cp_count; |
| 1167 | } |
| 1168 | return 0; |
| 1169 | } |
| 1170 | |
Domen Puncer | ebe8b54 | 2005-05-05 16:16:19 -0700 | [diff] [blame] | 1171 | /* a simple Shell sort */ |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1172 | static void groups_sort(struct group_info *group_info) |
| 1173 | { |
| 1174 | int base, max, stride; |
| 1175 | int gidsetsize = group_info->ngroups; |
| 1176 | |
| 1177 | for (stride = 1; stride < gidsetsize; stride = 3 * stride + 1) |
| 1178 | ; /* nothing */ |
| 1179 | stride /= 3; |
| 1180 | |
| 1181 | while (stride) { |
| 1182 | max = gidsetsize - stride; |
| 1183 | for (base = 0; base < max; base++) { |
| 1184 | int left = base; |
| 1185 | int right = left + stride; |
| 1186 | gid_t tmp = GROUP_AT(group_info, right); |
| 1187 | |
| 1188 | while (left >= 0 && GROUP_AT(group_info, left) > tmp) { |
| 1189 | GROUP_AT(group_info, right) = |
| 1190 | GROUP_AT(group_info, left); |
| 1191 | right = left; |
| 1192 | left -= stride; |
| 1193 | } |
| 1194 | GROUP_AT(group_info, right) = tmp; |
| 1195 | } |
| 1196 | stride /= 3; |
| 1197 | } |
| 1198 | } |
| 1199 | |
| 1200 | /* a simple bsearch */ |
David Howells | 3e30148 | 2005-06-23 22:00:56 -0700 | [diff] [blame] | 1201 | int groups_search(struct group_info *group_info, gid_t grp) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1202 | { |
Eric Dumazet | d74beb9f | 2006-03-25 03:08:19 -0800 | [diff] [blame] | 1203 | unsigned int left, right; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1204 | |
| 1205 | if (!group_info) |
| 1206 | return 0; |
| 1207 | |
| 1208 | left = 0; |
| 1209 | right = group_info->ngroups; |
| 1210 | while (left < right) { |
Eric Dumazet | d74beb9f | 2006-03-25 03:08:19 -0800 | [diff] [blame] | 1211 | unsigned int mid = (left+right)/2; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1212 | int cmp = grp - GROUP_AT(group_info, mid); |
| 1213 | if (cmp > 0) |
| 1214 | left = mid + 1; |
| 1215 | else if (cmp < 0) |
| 1216 | right = mid; |
| 1217 | else |
| 1218 | return 1; |
| 1219 | } |
| 1220 | return 0; |
| 1221 | } |
| 1222 | |
| 1223 | /* validate and set current->group_info */ |
| 1224 | int set_current_groups(struct group_info *group_info) |
| 1225 | { |
| 1226 | int retval; |
| 1227 | struct group_info *old_info; |
| 1228 | |
| 1229 | retval = security_task_setgroups(group_info); |
| 1230 | if (retval) |
| 1231 | return retval; |
| 1232 | |
| 1233 | groups_sort(group_info); |
| 1234 | get_group_info(group_info); |
| 1235 | |
| 1236 | task_lock(current); |
| 1237 | old_info = current->group_info; |
| 1238 | current->group_info = group_info; |
| 1239 | task_unlock(current); |
| 1240 | |
| 1241 | put_group_info(old_info); |
| 1242 | |
| 1243 | return 0; |
| 1244 | } |
| 1245 | |
| 1246 | EXPORT_SYMBOL(set_current_groups); |
| 1247 | |
| 1248 | asmlinkage long sys_getgroups(int gidsetsize, gid_t __user *grouplist) |
| 1249 | { |
| 1250 | int i = 0; |
| 1251 | |
| 1252 | /* |
| 1253 | * SMP: Nobody else can change our grouplist. Thus we are |
| 1254 | * safe. |
| 1255 | */ |
| 1256 | |
| 1257 | if (gidsetsize < 0) |
| 1258 | return -EINVAL; |
| 1259 | |
| 1260 | /* no need to grab task_lock here; it cannot change */ |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1261 | i = current->group_info->ngroups; |
| 1262 | if (gidsetsize) { |
| 1263 | if (i > gidsetsize) { |
| 1264 | i = -EINVAL; |
| 1265 | goto out; |
| 1266 | } |
| 1267 | if (groups_to_user(grouplist, current->group_info)) { |
| 1268 | i = -EFAULT; |
| 1269 | goto out; |
| 1270 | } |
| 1271 | } |
| 1272 | out: |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1273 | return i; |
| 1274 | } |
| 1275 | |
| 1276 | /* |
| 1277 | * SMP: Our groups are copy-on-write. We can set them safely |
| 1278 | * without another task interfering. |
| 1279 | */ |
| 1280 | |
| 1281 | asmlinkage long sys_setgroups(int gidsetsize, gid_t __user *grouplist) |
| 1282 | { |
| 1283 | struct group_info *group_info; |
| 1284 | int retval; |
| 1285 | |
| 1286 | if (!capable(CAP_SETGID)) |
| 1287 | return -EPERM; |
| 1288 | if ((unsigned)gidsetsize > NGROUPS_MAX) |
| 1289 | return -EINVAL; |
| 1290 | |
| 1291 | group_info = groups_alloc(gidsetsize); |
| 1292 | if (!group_info) |
| 1293 | return -ENOMEM; |
| 1294 | retval = groups_from_user(group_info, grouplist); |
| 1295 | if (retval) { |
| 1296 | put_group_info(group_info); |
| 1297 | return retval; |
| 1298 | } |
| 1299 | |
| 1300 | retval = set_current_groups(group_info); |
| 1301 | put_group_info(group_info); |
| 1302 | |
| 1303 | return retval; |
| 1304 | } |
| 1305 | |
| 1306 | /* |
| 1307 | * Check whether we're fsgid/egid or in the supplemental group.. |
| 1308 | */ |
| 1309 | int in_group_p(gid_t grp) |
| 1310 | { |
| 1311 | int retval = 1; |
Cal Peake | 756184b | 2006-09-30 23:27:24 -0700 | [diff] [blame] | 1312 | if (grp != current->fsgid) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1313 | retval = groups_search(current->group_info, grp); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1314 | return retval; |
| 1315 | } |
| 1316 | |
| 1317 | EXPORT_SYMBOL(in_group_p); |
| 1318 | |
| 1319 | int in_egroup_p(gid_t grp) |
| 1320 | { |
| 1321 | int retval = 1; |
Cal Peake | 756184b | 2006-09-30 23:27:24 -0700 | [diff] [blame] | 1322 | if (grp != current->egid) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1323 | retval = groups_search(current->group_info, grp); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1324 | return retval; |
| 1325 | } |
| 1326 | |
| 1327 | EXPORT_SYMBOL(in_egroup_p); |
| 1328 | |
| 1329 | DECLARE_RWSEM(uts_sem); |
| 1330 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1331 | asmlinkage long sys_newuname(struct new_utsname __user * name) |
| 1332 | { |
| 1333 | int errno = 0; |
| 1334 | |
| 1335 | down_read(&uts_sem); |
Serge E. Hallyn | e9ff399 | 2006-10-02 02:18:11 -0700 | [diff] [blame] | 1336 | if (copy_to_user(name, utsname(), sizeof *name)) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1337 | errno = -EFAULT; |
| 1338 | up_read(&uts_sem); |
| 1339 | return errno; |
| 1340 | } |
| 1341 | |
| 1342 | asmlinkage long sys_sethostname(char __user *name, int len) |
| 1343 | { |
| 1344 | int errno; |
| 1345 | char tmp[__NEW_UTS_LEN]; |
| 1346 | |
| 1347 | if (!capable(CAP_SYS_ADMIN)) |
| 1348 | return -EPERM; |
| 1349 | if (len < 0 || len > __NEW_UTS_LEN) |
| 1350 | return -EINVAL; |
| 1351 | down_write(&uts_sem); |
| 1352 | errno = -EFAULT; |
| 1353 | if (!copy_from_user(tmp, name, len)) { |
Serge E. Hallyn | e9ff399 | 2006-10-02 02:18:11 -0700 | [diff] [blame] | 1354 | memcpy(utsname()->nodename, tmp, len); |
| 1355 | utsname()->nodename[len] = 0; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1356 | errno = 0; |
| 1357 | } |
| 1358 | up_write(&uts_sem); |
| 1359 | return errno; |
| 1360 | } |
| 1361 | |
| 1362 | #ifdef __ARCH_WANT_SYS_GETHOSTNAME |
| 1363 | |
| 1364 | asmlinkage long sys_gethostname(char __user *name, int len) |
| 1365 | { |
| 1366 | int i, errno; |
| 1367 | |
| 1368 | if (len < 0) |
| 1369 | return -EINVAL; |
| 1370 | down_read(&uts_sem); |
Serge E. Hallyn | e9ff399 | 2006-10-02 02:18:11 -0700 | [diff] [blame] | 1371 | i = 1 + strlen(utsname()->nodename); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1372 | if (i > len) |
| 1373 | i = len; |
| 1374 | errno = 0; |
Serge E. Hallyn | e9ff399 | 2006-10-02 02:18:11 -0700 | [diff] [blame] | 1375 | if (copy_to_user(name, utsname()->nodename, i)) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1376 | errno = -EFAULT; |
| 1377 | up_read(&uts_sem); |
| 1378 | return errno; |
| 1379 | } |
| 1380 | |
| 1381 | #endif |
| 1382 | |
| 1383 | /* |
| 1384 | * Only setdomainname; getdomainname can be implemented by calling |
| 1385 | * uname() |
| 1386 | */ |
| 1387 | asmlinkage long sys_setdomainname(char __user *name, int len) |
| 1388 | { |
| 1389 | int errno; |
| 1390 | char tmp[__NEW_UTS_LEN]; |
| 1391 | |
| 1392 | if (!capable(CAP_SYS_ADMIN)) |
| 1393 | return -EPERM; |
| 1394 | if (len < 0 || len > __NEW_UTS_LEN) |
| 1395 | return -EINVAL; |
| 1396 | |
| 1397 | down_write(&uts_sem); |
| 1398 | errno = -EFAULT; |
| 1399 | if (!copy_from_user(tmp, name, len)) { |
Serge E. Hallyn | e9ff399 | 2006-10-02 02:18:11 -0700 | [diff] [blame] | 1400 | memcpy(utsname()->domainname, tmp, len); |
| 1401 | utsname()->domainname[len] = 0; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1402 | errno = 0; |
| 1403 | } |
| 1404 | up_write(&uts_sem); |
| 1405 | return errno; |
| 1406 | } |
| 1407 | |
| 1408 | asmlinkage long sys_getrlimit(unsigned int resource, struct rlimit __user *rlim) |
| 1409 | { |
| 1410 | if (resource >= RLIM_NLIMITS) |
| 1411 | return -EINVAL; |
| 1412 | else { |
| 1413 | struct rlimit value; |
| 1414 | task_lock(current->group_leader); |
| 1415 | value = current->signal->rlim[resource]; |
| 1416 | task_unlock(current->group_leader); |
| 1417 | return copy_to_user(rlim, &value, sizeof(*rlim)) ? -EFAULT : 0; |
| 1418 | } |
| 1419 | } |
| 1420 | |
| 1421 | #ifdef __ARCH_WANT_SYS_OLD_GETRLIMIT |
| 1422 | |
| 1423 | /* |
| 1424 | * Back compatibility for getrlimit. Needed for some apps. |
| 1425 | */ |
| 1426 | |
| 1427 | asmlinkage long sys_old_getrlimit(unsigned int resource, struct rlimit __user *rlim) |
| 1428 | { |
| 1429 | struct rlimit x; |
| 1430 | if (resource >= RLIM_NLIMITS) |
| 1431 | return -EINVAL; |
| 1432 | |
| 1433 | task_lock(current->group_leader); |
| 1434 | x = current->signal->rlim[resource]; |
| 1435 | task_unlock(current->group_leader); |
Cal Peake | 756184b | 2006-09-30 23:27:24 -0700 | [diff] [blame] | 1436 | if (x.rlim_cur > 0x7FFFFFFF) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1437 | x.rlim_cur = 0x7FFFFFFF; |
Cal Peake | 756184b | 2006-09-30 23:27:24 -0700 | [diff] [blame] | 1438 | if (x.rlim_max > 0x7FFFFFFF) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1439 | x.rlim_max = 0x7FFFFFFF; |
| 1440 | return copy_to_user(rlim, &x, sizeof(x))?-EFAULT:0; |
| 1441 | } |
| 1442 | |
| 1443 | #endif |
| 1444 | |
| 1445 | asmlinkage long sys_setrlimit(unsigned int resource, struct rlimit __user *rlim) |
| 1446 | { |
| 1447 | struct rlimit new_rlim, *old_rlim; |
Andrew Morton | ec9e16b | 2006-03-24 03:18:34 -0800 | [diff] [blame] | 1448 | unsigned long it_prof_secs; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1449 | int retval; |
| 1450 | |
| 1451 | if (resource >= RLIM_NLIMITS) |
| 1452 | return -EINVAL; |
Andrew Morton | ec9e16b | 2006-03-24 03:18:34 -0800 | [diff] [blame] | 1453 | if (copy_from_user(&new_rlim, rlim, sizeof(*rlim))) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1454 | return -EFAULT; |
Andrew Morton | ec9e16b | 2006-03-24 03:18:34 -0800 | [diff] [blame] | 1455 | if (new_rlim.rlim_cur > new_rlim.rlim_max) |
| 1456 | return -EINVAL; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1457 | old_rlim = current->signal->rlim + resource; |
| 1458 | if ((new_rlim.rlim_max > old_rlim->rlim_max) && |
| 1459 | !capable(CAP_SYS_RESOURCE)) |
| 1460 | return -EPERM; |
Eric Dumazet | 9cfe015 | 2008-02-06 01:37:16 -0800 | [diff] [blame] | 1461 | if (resource == RLIMIT_NOFILE && new_rlim.rlim_max > sysctl_nr_open) |
Andrew Morton | ec9e16b | 2006-03-24 03:18:34 -0800 | [diff] [blame] | 1462 | return -EPERM; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1463 | |
| 1464 | retval = security_task_setrlimit(resource, &new_rlim); |
| 1465 | if (retval) |
| 1466 | return retval; |
| 1467 | |
Tom Alsberg | 9926e4c | 2007-05-08 00:30:31 -0700 | [diff] [blame] | 1468 | if (resource == RLIMIT_CPU && new_rlim.rlim_cur == 0) { |
| 1469 | /* |
| 1470 | * The caller is asking for an immediate RLIMIT_CPU |
| 1471 | * expiry. But we use the zero value to mean "it was |
| 1472 | * never set". So let's cheat and make it one second |
| 1473 | * instead |
| 1474 | */ |
| 1475 | new_rlim.rlim_cur = 1; |
| 1476 | } |
| 1477 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1478 | task_lock(current->group_leader); |
| 1479 | *old_rlim = new_rlim; |
| 1480 | task_unlock(current->group_leader); |
| 1481 | |
Andrew Morton | ec9e16b | 2006-03-24 03:18:34 -0800 | [diff] [blame] | 1482 | if (resource != RLIMIT_CPU) |
| 1483 | goto out; |
Andrew Morton | d3561f7 | 2006-03-24 03:18:36 -0800 | [diff] [blame] | 1484 | |
| 1485 | /* |
| 1486 | * RLIMIT_CPU handling. Note that the kernel fails to return an error |
| 1487 | * code if it rejected the user's attempt to set RLIMIT_CPU. This is a |
| 1488 | * very long-standing error, and fixing it now risks breakage of |
| 1489 | * applications, so we live with it |
| 1490 | */ |
Andrew Morton | ec9e16b | 2006-03-24 03:18:34 -0800 | [diff] [blame] | 1491 | if (new_rlim.rlim_cur == RLIM_INFINITY) |
| 1492 | goto out; |
| 1493 | |
| 1494 | it_prof_secs = cputime_to_secs(current->signal->it_prof_expires); |
| 1495 | if (it_prof_secs == 0 || new_rlim.rlim_cur <= it_prof_secs) { |
Andrew Morton | e066111 | 2006-03-24 03:18:35 -0800 | [diff] [blame] | 1496 | unsigned long rlim_cur = new_rlim.rlim_cur; |
| 1497 | cputime_t cputime; |
Andrew Morton | ec9e16b | 2006-03-24 03:18:34 -0800 | [diff] [blame] | 1498 | |
Andrew Morton | e066111 | 2006-03-24 03:18:35 -0800 | [diff] [blame] | 1499 | cputime = secs_to_cputime(rlim_cur); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1500 | read_lock(&tasklist_lock); |
| 1501 | spin_lock_irq(¤t->sighand->siglock); |
Andrew Morton | ec9e16b | 2006-03-24 03:18:34 -0800 | [diff] [blame] | 1502 | set_process_cpu_timer(current, CPUCLOCK_PROF, &cputime, NULL); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1503 | spin_unlock_irq(¤t->sighand->siglock); |
| 1504 | read_unlock(&tasklist_lock); |
| 1505 | } |
Andrew Morton | ec9e16b | 2006-03-24 03:18:34 -0800 | [diff] [blame] | 1506 | out: |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1507 | return 0; |
| 1508 | } |
| 1509 | |
| 1510 | /* |
| 1511 | * It would make sense to put struct rusage in the task_struct, |
| 1512 | * except that would make the task_struct be *really big*. After |
| 1513 | * task_struct gets moved into malloc'ed memory, it would |
| 1514 | * make sense to do this. It will make moving the rest of the information |
| 1515 | * a lot simpler! (Which we're not doing right now because we're not |
| 1516 | * measuring them yet). |
| 1517 | * |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1518 | * When sampling multiple threads for RUSAGE_SELF, under SMP we might have |
| 1519 | * races with threads incrementing their own counters. But since word |
| 1520 | * reads are atomic, we either get new values or old values and we don't |
| 1521 | * care which for the sums. We always take the siglock to protect reading |
| 1522 | * the c* fields from p->signal from races with exit.c updating those |
| 1523 | * fields when reaping, so a sample either gets all the additions of a |
| 1524 | * given child after it's reaped, or none so this sample is before reaping. |
Ravikiran G Thirumalai | 2dd0ebc | 2006-03-23 03:00:13 -0800 | [diff] [blame] | 1525 | * |
Ravikiran G Thirumalai | de047c1 | 2006-06-22 14:47:26 -0700 | [diff] [blame] | 1526 | * Locking: |
| 1527 | * We need to take the siglock for CHILDEREN, SELF and BOTH |
| 1528 | * for the cases current multithreaded, non-current single threaded |
| 1529 | * non-current multithreaded. Thread traversal is now safe with |
| 1530 | * the siglock held. |
| 1531 | * Strictly speaking, we donot need to take the siglock if we are current and |
| 1532 | * single threaded, as no one else can take our signal_struct away, no one |
| 1533 | * else can reap the children to update signal->c* counters, and no one else |
| 1534 | * can race with the signal-> fields. If we do not take any lock, the |
| 1535 | * signal-> fields could be read out of order while another thread was just |
| 1536 | * exiting. So we should place a read memory barrier when we avoid the lock. |
| 1537 | * On the writer side, write memory barrier is implied in __exit_signal |
| 1538 | * as __exit_signal releases the siglock spinlock after updating the signal-> |
| 1539 | * fields. But we don't do this yet to keep things simple. |
Ravikiran G Thirumalai | 2dd0ebc | 2006-03-23 03:00:13 -0800 | [diff] [blame] | 1540 | * |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1541 | */ |
| 1542 | |
Sripathi Kodi | 679c9cd | 2008-04-29 00:58:42 -0700 | [diff] [blame] | 1543 | static void accumulate_thread_rusage(struct task_struct *t, struct rusage *r, |
| 1544 | cputime_t *utimep, cputime_t *stimep) |
| 1545 | { |
| 1546 | *utimep = cputime_add(*utimep, t->utime); |
| 1547 | *stimep = cputime_add(*stimep, t->stime); |
| 1548 | r->ru_nvcsw += t->nvcsw; |
| 1549 | r->ru_nivcsw += t->nivcsw; |
| 1550 | r->ru_minflt += t->min_flt; |
| 1551 | r->ru_majflt += t->maj_flt; |
| 1552 | r->ru_inblock += task_io_get_inblock(t); |
| 1553 | r->ru_oublock += task_io_get_oublock(t); |
| 1554 | } |
| 1555 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1556 | static void k_getrusage(struct task_struct *p, int who, struct rusage *r) |
| 1557 | { |
| 1558 | struct task_struct *t; |
| 1559 | unsigned long flags; |
| 1560 | cputime_t utime, stime; |
| 1561 | |
| 1562 | memset((char *) r, 0, sizeof *r); |
Oleg Nesterov | 0f59cc4 | 2006-01-08 01:05:15 -0800 | [diff] [blame] | 1563 | utime = stime = cputime_zero; |
| 1564 | |
Sripathi Kodi | 679c9cd | 2008-04-29 00:58:42 -0700 | [diff] [blame] | 1565 | if (who == RUSAGE_THREAD) { |
| 1566 | accumulate_thread_rusage(p, r, &utime, &stime); |
| 1567 | goto out; |
| 1568 | } |
| 1569 | |
Oleg Nesterov | d6cf723 | 2008-04-30 00:52:38 -0700 | [diff] [blame] | 1570 | if (!lock_task_sighand(p, &flags)) |
Ravikiran G Thirumalai | de047c1 | 2006-06-22 14:47:26 -0700 | [diff] [blame] | 1571 | return; |
Ravikiran G Thirumalai | 2dd0ebc | 2006-03-23 03:00:13 -0800 | [diff] [blame] | 1572 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1573 | switch (who) { |
Oleg Nesterov | 0f59cc4 | 2006-01-08 01:05:15 -0800 | [diff] [blame] | 1574 | case RUSAGE_BOTH: |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1575 | case RUSAGE_CHILDREN: |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1576 | utime = p->signal->cutime; |
| 1577 | stime = p->signal->cstime; |
| 1578 | r->ru_nvcsw = p->signal->cnvcsw; |
| 1579 | r->ru_nivcsw = p->signal->cnivcsw; |
| 1580 | r->ru_minflt = p->signal->cmin_flt; |
| 1581 | r->ru_majflt = p->signal->cmaj_flt; |
Eric Dumazet | 6eaeeab | 2007-05-10 22:22:37 -0700 | [diff] [blame] | 1582 | r->ru_inblock = p->signal->cinblock; |
| 1583 | r->ru_oublock = p->signal->coublock; |
Oleg Nesterov | 0f59cc4 | 2006-01-08 01:05:15 -0800 | [diff] [blame] | 1584 | |
| 1585 | if (who == RUSAGE_CHILDREN) |
| 1586 | break; |
| 1587 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1588 | case RUSAGE_SELF: |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1589 | utime = cputime_add(utime, p->signal->utime); |
| 1590 | stime = cputime_add(stime, p->signal->stime); |
| 1591 | r->ru_nvcsw += p->signal->nvcsw; |
| 1592 | r->ru_nivcsw += p->signal->nivcsw; |
| 1593 | r->ru_minflt += p->signal->min_flt; |
| 1594 | r->ru_majflt += p->signal->maj_flt; |
Eric Dumazet | 6eaeeab | 2007-05-10 22:22:37 -0700 | [diff] [blame] | 1595 | r->ru_inblock += p->signal->inblock; |
| 1596 | r->ru_oublock += p->signal->oublock; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1597 | t = p; |
| 1598 | do { |
Sripathi Kodi | 679c9cd | 2008-04-29 00:58:42 -0700 | [diff] [blame] | 1599 | accumulate_thread_rusage(t, r, &utime, &stime); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1600 | t = next_thread(t); |
| 1601 | } while (t != p); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1602 | break; |
Oleg Nesterov | 0f59cc4 | 2006-01-08 01:05:15 -0800 | [diff] [blame] | 1603 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1604 | default: |
| 1605 | BUG(); |
| 1606 | } |
Ravikiran G Thirumalai | de047c1 | 2006-06-22 14:47:26 -0700 | [diff] [blame] | 1607 | unlock_task_sighand(p, &flags); |
Ravikiran G Thirumalai | de047c1 | 2006-06-22 14:47:26 -0700 | [diff] [blame] | 1608 | |
Sripathi Kodi | 679c9cd | 2008-04-29 00:58:42 -0700 | [diff] [blame] | 1609 | out: |
Oleg Nesterov | 0f59cc4 | 2006-01-08 01:05:15 -0800 | [diff] [blame] | 1610 | cputime_to_timeval(utime, &r->ru_utime); |
| 1611 | cputime_to_timeval(stime, &r->ru_stime); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1612 | } |
| 1613 | |
| 1614 | int getrusage(struct task_struct *p, int who, struct rusage __user *ru) |
| 1615 | { |
| 1616 | struct rusage r; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1617 | k_getrusage(p, who, &r); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1618 | return copy_to_user(ru, &r, sizeof(r)) ? -EFAULT : 0; |
| 1619 | } |
| 1620 | |
| 1621 | asmlinkage long sys_getrusage(int who, struct rusage __user *ru) |
| 1622 | { |
Sripathi Kodi | 679c9cd | 2008-04-29 00:58:42 -0700 | [diff] [blame] | 1623 | if (who != RUSAGE_SELF && who != RUSAGE_CHILDREN && |
| 1624 | who != RUSAGE_THREAD) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1625 | return -EINVAL; |
| 1626 | return getrusage(current, who, ru); |
| 1627 | } |
| 1628 | |
| 1629 | asmlinkage long sys_umask(int mask) |
| 1630 | { |
| 1631 | mask = xchg(¤t->fs->umask, mask & S_IRWXUGO); |
| 1632 | return mask; |
| 1633 | } |
Serge E. Hallyn | 3b7391d | 2008-02-04 22:29:45 -0800 | [diff] [blame] | 1634 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1635 | asmlinkage long sys_prctl(int option, unsigned long arg2, unsigned long arg3, |
| 1636 | unsigned long arg4, unsigned long arg5) |
| 1637 | { |
Shi Weihua | 7b26655 | 2008-05-23 13:04:59 -0700 | [diff] [blame] | 1638 | long error = 0; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1639 | |
Andrew G. Morgan | 3898b1b | 2008-04-28 02:13:40 -0700 | [diff] [blame] | 1640 | if (security_task_prctl(option, arg2, arg3, arg4, arg5, &error)) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1641 | return error; |
| 1642 | |
| 1643 | switch (option) { |
| 1644 | case PR_SET_PDEATHSIG: |
Jesper Juhl | 0730ded | 2005-09-06 15:17:37 -0700 | [diff] [blame] | 1645 | if (!valid_signal(arg2)) { |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1646 | error = -EINVAL; |
| 1647 | break; |
| 1648 | } |
Jesper Juhl | 0730ded | 2005-09-06 15:17:37 -0700 | [diff] [blame] | 1649 | current->pdeath_signal = arg2; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1650 | break; |
| 1651 | case PR_GET_PDEATHSIG: |
| 1652 | error = put_user(current->pdeath_signal, (int __user *)arg2); |
| 1653 | break; |
| 1654 | case PR_GET_DUMPABLE: |
Kawai, Hidehiro | 6c5d523 | 2007-07-19 01:48:27 -0700 | [diff] [blame] | 1655 | error = get_dumpable(current->mm); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1656 | break; |
| 1657 | case PR_SET_DUMPABLE: |
Marcel Holtmann | abf75a5 | 2006-07-12 13:12:00 +0200 | [diff] [blame] | 1658 | if (arg2 < 0 || arg2 > 1) { |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1659 | error = -EINVAL; |
| 1660 | break; |
| 1661 | } |
Kawai, Hidehiro | 6c5d523 | 2007-07-19 01:48:27 -0700 | [diff] [blame] | 1662 | set_dumpable(current->mm, arg2); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1663 | break; |
| 1664 | |
| 1665 | case PR_SET_UNALIGN: |
| 1666 | error = SET_UNALIGN_CTL(current, arg2); |
| 1667 | break; |
| 1668 | case PR_GET_UNALIGN: |
| 1669 | error = GET_UNALIGN_CTL(current, arg2); |
| 1670 | break; |
| 1671 | case PR_SET_FPEMU: |
| 1672 | error = SET_FPEMU_CTL(current, arg2); |
| 1673 | break; |
| 1674 | case PR_GET_FPEMU: |
| 1675 | error = GET_FPEMU_CTL(current, arg2); |
| 1676 | break; |
| 1677 | case PR_SET_FPEXC: |
| 1678 | error = SET_FPEXC_CTL(current, arg2); |
| 1679 | break; |
| 1680 | case PR_GET_FPEXC: |
| 1681 | error = GET_FPEXC_CTL(current, arg2); |
| 1682 | break; |
| 1683 | case PR_GET_TIMING: |
| 1684 | error = PR_TIMING_STATISTICAL; |
| 1685 | break; |
| 1686 | case PR_SET_TIMING: |
Shi Weihua | 7b26655 | 2008-05-23 13:04:59 -0700 | [diff] [blame] | 1687 | if (arg2 != PR_TIMING_STATISTICAL) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1688 | error = -EINVAL; |
| 1689 | break; |
| 1690 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1691 | case PR_SET_NAME: { |
| 1692 | struct task_struct *me = current; |
| 1693 | unsigned char ncomm[sizeof(me->comm)]; |
| 1694 | |
| 1695 | ncomm[sizeof(me->comm)-1] = 0; |
| 1696 | if (strncpy_from_user(ncomm, (char __user *)arg2, |
| 1697 | sizeof(me->comm)-1) < 0) |
| 1698 | return -EFAULT; |
| 1699 | set_task_comm(me, ncomm); |
| 1700 | return 0; |
| 1701 | } |
| 1702 | case PR_GET_NAME: { |
| 1703 | struct task_struct *me = current; |
| 1704 | unsigned char tcomm[sizeof(me->comm)]; |
| 1705 | |
| 1706 | get_task_comm(tcomm, me); |
| 1707 | if (copy_to_user((char __user *)arg2, tcomm, sizeof(tcomm))) |
| 1708 | return -EFAULT; |
| 1709 | return 0; |
| 1710 | } |
Anton Blanchard | 651d765 | 2006-06-07 16:10:19 +1000 | [diff] [blame] | 1711 | case PR_GET_ENDIAN: |
| 1712 | error = GET_ENDIAN(current, arg2); |
| 1713 | break; |
| 1714 | case PR_SET_ENDIAN: |
| 1715 | error = SET_ENDIAN(current, arg2); |
| 1716 | break; |
| 1717 | |
Andrea Arcangeli | 1d9d02f | 2007-07-15 23:41:32 -0700 | [diff] [blame] | 1718 | case PR_GET_SECCOMP: |
| 1719 | error = prctl_get_seccomp(); |
| 1720 | break; |
| 1721 | case PR_SET_SECCOMP: |
| 1722 | error = prctl_set_seccomp(arg2); |
| 1723 | break; |
Erik Bosman | 8fb402b | 2008-04-11 18:54:17 +0200 | [diff] [blame] | 1724 | case PR_GET_TSC: |
| 1725 | error = GET_TSC_CTL(arg2); |
| 1726 | break; |
| 1727 | case PR_SET_TSC: |
| 1728 | error = SET_TSC_CTL(arg2); |
| 1729 | break; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1730 | default: |
| 1731 | error = -EINVAL; |
| 1732 | break; |
| 1733 | } |
| 1734 | return error; |
| 1735 | } |
Andi Kleen | 3cfc348 | 2006-09-26 10:52:28 +0200 | [diff] [blame] | 1736 | |
| 1737 | asmlinkage long sys_getcpu(unsigned __user *cpup, unsigned __user *nodep, |
Ingo Molnar | 4307d1e | 2007-11-07 18:37:48 +0100 | [diff] [blame] | 1738 | struct getcpu_cache __user *unused) |
Andi Kleen | 3cfc348 | 2006-09-26 10:52:28 +0200 | [diff] [blame] | 1739 | { |
| 1740 | int err = 0; |
| 1741 | int cpu = raw_smp_processor_id(); |
| 1742 | if (cpup) |
| 1743 | err |= put_user(cpu, cpup); |
| 1744 | if (nodep) |
| 1745 | err |= put_user(cpu_to_node(cpu), nodep); |
Andi Kleen | 3cfc348 | 2006-09-26 10:52:28 +0200 | [diff] [blame] | 1746 | return err ? -EFAULT : 0; |
| 1747 | } |
Jeremy Fitzhardinge | 10a0a8d | 2007-07-17 18:37:02 -0700 | [diff] [blame] | 1748 | |
| 1749 | char poweroff_cmd[POWEROFF_CMD_PATH_LEN] = "/sbin/poweroff"; |
| 1750 | |
| 1751 | static void argv_cleanup(char **argv, char **envp) |
| 1752 | { |
| 1753 | argv_free(argv); |
| 1754 | } |
| 1755 | |
| 1756 | /** |
| 1757 | * orderly_poweroff - Trigger an orderly system poweroff |
| 1758 | * @force: force poweroff if command execution fails |
| 1759 | * |
| 1760 | * This may be called from any context to trigger a system shutdown. |
| 1761 | * If the orderly shutdown fails, it will force an immediate shutdown. |
| 1762 | */ |
| 1763 | int orderly_poweroff(bool force) |
| 1764 | { |
| 1765 | int argc; |
| 1766 | char **argv = argv_split(GFP_ATOMIC, poweroff_cmd, &argc); |
| 1767 | static char *envp[] = { |
| 1768 | "HOME=/", |
| 1769 | "PATH=/sbin:/bin:/usr/sbin:/usr/bin", |
| 1770 | NULL |
| 1771 | }; |
| 1772 | int ret = -ENOMEM; |
| 1773 | struct subprocess_info *info; |
| 1774 | |
| 1775 | if (argv == NULL) { |
| 1776 | printk(KERN_WARNING "%s failed to allocate memory for \"%s\"\n", |
| 1777 | __func__, poweroff_cmd); |
| 1778 | goto out; |
| 1779 | } |
| 1780 | |
KOSAKI Motohiro | ac331d1 | 2008-07-25 01:45:38 -0700 | [diff] [blame] | 1781 | info = call_usermodehelper_setup(argv[0], argv, envp, GFP_ATOMIC); |
Jeremy Fitzhardinge | 10a0a8d | 2007-07-17 18:37:02 -0700 | [diff] [blame] | 1782 | if (info == NULL) { |
| 1783 | argv_free(argv); |
| 1784 | goto out; |
| 1785 | } |
| 1786 | |
| 1787 | call_usermodehelper_setcleanup(info, argv_cleanup); |
| 1788 | |
Jeremy Fitzhardinge | 86313c4 | 2007-07-17 18:37:03 -0700 | [diff] [blame] | 1789 | ret = call_usermodehelper_exec(info, UMH_NO_WAIT); |
Jeremy Fitzhardinge | 10a0a8d | 2007-07-17 18:37:02 -0700 | [diff] [blame] | 1790 | |
| 1791 | out: |
| 1792 | if (ret && force) { |
| 1793 | printk(KERN_WARNING "Failed to start orderly shutdown: " |
| 1794 | "forcing the issue\n"); |
| 1795 | |
| 1796 | /* I guess this should try to kick off some daemon to |
| 1797 | sync and poweroff asap. Or not even bother syncing |
| 1798 | if we're doing an emergency shutdown? */ |
| 1799 | emergency_sync(); |
| 1800 | kernel_power_off(); |
| 1801 | } |
| 1802 | |
| 1803 | return ret; |
| 1804 | } |
| 1805 | EXPORT_SYMBOL_GPL(orderly_poweroff); |