4 * Copyright (C) 1991, 1992 Linus Torvalds
7 #include <linux/export.h>
9 #include <linux/utsname.h>
10 #include <linux/mman.h>
11 #include <linux/reboot.h>
12 #include <linux/prctl.h>
13 #include <linux/highuid.h>
15 #include <linux/kmod.h>
16 #include <linux/perf_event.h>
17 #include <linux/resource.h>
18 #include <linux/kernel.h>
19 #include <linux/workqueue.h>
20 #include <linux/capability.h>
21 #include <linux/device.h>
22 #include <linux/key.h>
23 #include <linux/times.h>
24 #include <linux/posix-timers.h>
25 #include <linux/security.h>
26 #include <linux/dcookies.h>
27 #include <linux/suspend.h>
28 #include <linux/tty.h>
29 #include <linux/signal.h>
30 #include <linux/cn_proc.h>
31 #include <linux/getcpu.h>
32 #include <linux/task_io_accounting_ops.h>
33 #include <linux/seccomp.h>
34 #include <linux/cpu.h>
35 #include <linux/personality.h>
36 #include <linux/ptrace.h>
37 #include <linux/fs_struct.h>
38 #include <linux/file.h>
39 #include <linux/mount.h>
40 #include <linux/gfp.h>
41 #include <linux/syscore_ops.h>
42 #include <linux/version.h>
43 #include <linux/ctype.h>
45 #include <linux/compat.h>
46 #include <linux/syscalls.h>
47 #include <linux/kprobes.h>
48 #include <linux/user_namespace.h>
49 #include <linux/binfmts.h>
51 #include <linux/sched.h>
52 #include <linux/rcupdate.h>
53 #include <linux/uidgid.h>
54 #include <linux/cred.h>
56 #include <linux/kmsg_dump.h>
57 /* Move somewhere else to avoid recompiling? */
58 #include <generated/utsrelease.h>
60 #include <asm/uaccess.h>
62 #include <asm/unistd.h>
64 #ifndef SET_UNALIGN_CTL
65 # define SET_UNALIGN_CTL(a,b) (-EINVAL)
67 #ifndef GET_UNALIGN_CTL
68 # define GET_UNALIGN_CTL(a,b) (-EINVAL)
71 # define SET_FPEMU_CTL(a,b) (-EINVAL)
74 # define GET_FPEMU_CTL(a,b) (-EINVAL)
77 # define SET_FPEXC_CTL(a,b) (-EINVAL)
80 # define GET_FPEXC_CTL(a,b) (-EINVAL)
83 # define GET_ENDIAN(a,b) (-EINVAL)
86 # define SET_ENDIAN(a,b) (-EINVAL)
89 # define GET_TSC_CTL(a) (-EINVAL)
92 # define SET_TSC_CTL(a) (-EINVAL)
96 * this is where the system-wide overflow UID and GID are defined, for
97 * architectures that now have 32-bit UID/GID but didn't in the past
100 int overflowuid = DEFAULT_OVERFLOWUID;
101 int overflowgid = DEFAULT_OVERFLOWGID;
103 EXPORT_SYMBOL(overflowuid);
104 EXPORT_SYMBOL(overflowgid);
107 * the same as above, but for filesystems which can only store a 16-bit
108 * UID and GID. as such, this is needed on all architectures
111 int fs_overflowuid = DEFAULT_FS_OVERFLOWUID;
112 int fs_overflowgid = DEFAULT_FS_OVERFLOWUID;
114 EXPORT_SYMBOL(fs_overflowuid);
115 EXPORT_SYMBOL(fs_overflowgid);
118 * Returns true if current's euid is same as p's uid or euid,
119 * or has CAP_SYS_NICE to p's user_ns.
121 * Called with rcu_read_lock, creds are safe
123 static bool set_one_prio_perm(struct task_struct *p)
125 const struct cred *cred = current_cred(), *pcred = __task_cred(p);
127 if (uid_eq(pcred->uid, cred->euid) ||
128 uid_eq(pcred->euid, cred->euid))
130 if (ns_capable(pcred->user_ns, CAP_SYS_NICE))
136 * set the priority of a task
137 * - the caller must hold the RCU read lock
139 static int set_one_prio(struct task_struct *p, int niceval, int error)
143 if (!set_one_prio_perm(p)) {
147 if (niceval < task_nice(p) && !can_nice(p, niceval)) {
151 no_nice = security_task_setnice(p, niceval);
158 set_user_nice(p, niceval);
163 SYSCALL_DEFINE3(setpriority, int, which, int, who, int, niceval)
165 struct task_struct *g, *p;
166 struct user_struct *user;
167 const struct cred *cred = current_cred();
172 if (which > PRIO_USER || which < PRIO_PROCESS)
175 /* normalize: avoid signed division (rounding problems) */
177 if (niceval < MIN_NICE)
179 if (niceval > MAX_NICE)
183 read_lock(&tasklist_lock);
187 p = find_task_by_vpid(who);
191 error = set_one_prio(p, niceval, error);
195 pgrp = find_vpid(who);
197 pgrp = task_pgrp(current);
198 do_each_pid_thread(pgrp, PIDTYPE_PGID, p) {
199 error = set_one_prio(p, niceval, error);
200 } while_each_pid_thread(pgrp, PIDTYPE_PGID, p);
203 uid = make_kuid(cred->user_ns, who);
207 else if (!uid_eq(uid, cred->uid) &&
208 !(user = find_user(uid)))
209 goto out_unlock; /* No processes for this user */
211 do_each_thread(g, p) {
212 if (uid_eq(task_uid(p), uid))
213 error = set_one_prio(p, niceval, error);
214 } while_each_thread(g, p);
215 if (!uid_eq(uid, cred->uid))
216 free_uid(user); /* For find_user() */
220 read_unlock(&tasklist_lock);
227 * Ugh. To avoid negative return values, "getpriority()" will
228 * not return the normal nice-value, but a negated value that
229 * has been offset by 20 (ie it returns 40..1 instead of -20..19)
230 * to stay compatible.
232 SYSCALL_DEFINE2(getpriority, int, which, int, who)
234 struct task_struct *g, *p;
235 struct user_struct *user;
236 const struct cred *cred = current_cred();
237 long niceval, retval = -ESRCH;
241 if (which > PRIO_USER || which < PRIO_PROCESS)
245 read_lock(&tasklist_lock);
249 p = find_task_by_vpid(who);
253 niceval = nice_to_rlimit(task_nice(p));
254 if (niceval > retval)
260 pgrp = find_vpid(who);
262 pgrp = task_pgrp(current);
263 do_each_pid_thread(pgrp, PIDTYPE_PGID, p) {
264 niceval = nice_to_rlimit(task_nice(p));
265 if (niceval > retval)
267 } while_each_pid_thread(pgrp, PIDTYPE_PGID, p);
270 uid = make_kuid(cred->user_ns, who);
274 else if (!uid_eq(uid, cred->uid) &&
275 !(user = find_user(uid)))
276 goto out_unlock; /* No processes for this user */
278 do_each_thread(g, p) {
279 if (uid_eq(task_uid(p), uid)) {
280 niceval = nice_to_rlimit(task_nice(p));
281 if (niceval > retval)
284 } while_each_thread(g, p);
285 if (!uid_eq(uid, cred->uid))
286 free_uid(user); /* for find_user() */
290 read_unlock(&tasklist_lock);
297 * Unprivileged users may change the real gid to the effective gid
298 * or vice versa. (BSD-style)
300 * If you set the real gid at all, or set the effective gid to a value not
301 * equal to the real gid, then the saved gid is set to the new effective gid.
303 * This makes it possible for a setgid program to completely drop its
304 * privileges, which is often a useful assertion to make when you are doing
305 * a security audit over a program.
307 * The general idea is that a program which uses just setregid() will be
308 * 100% compatible with BSD. A program which uses just setgid() will be
309 * 100% compatible with POSIX with saved IDs.
311 * SMP: There are not races, the GIDs are checked only by filesystem
312 * operations (as far as semantic preservation is concerned).
314 SYSCALL_DEFINE2(setregid, gid_t, rgid, gid_t, egid)
316 struct user_namespace *ns = current_user_ns();
317 const struct cred *old;
322 krgid = make_kgid(ns, rgid);
323 kegid = make_kgid(ns, egid);
325 if ((rgid != (gid_t) -1) && !gid_valid(krgid))
327 if ((egid != (gid_t) -1) && !gid_valid(kegid))
330 new = prepare_creds();
333 old = current_cred();
336 if (rgid != (gid_t) -1) {
337 if (gid_eq(old->gid, krgid) ||
338 gid_eq(old->egid, krgid) ||
339 ns_capable(old->user_ns, CAP_SETGID))
344 if (egid != (gid_t) -1) {
345 if (gid_eq(old->gid, kegid) ||
346 gid_eq(old->egid, kegid) ||
347 gid_eq(old->sgid, kegid) ||
348 ns_capable(old->user_ns, CAP_SETGID))
354 if (rgid != (gid_t) -1 ||
355 (egid != (gid_t) -1 && !gid_eq(kegid, old->gid)))
356 new->sgid = new->egid;
357 new->fsgid = new->egid;
359 return commit_creds(new);
367 * setgid() is implemented like SysV w/ SAVED_IDS
369 * SMP: Same implicit races as above.
371 SYSCALL_DEFINE1(setgid, gid_t, gid)
373 struct user_namespace *ns = current_user_ns();
374 const struct cred *old;
379 kgid = make_kgid(ns, gid);
380 if (!gid_valid(kgid))
383 new = prepare_creds();
386 old = current_cred();
389 if (ns_capable(old->user_ns, CAP_SETGID))
390 new->gid = new->egid = new->sgid = new->fsgid = kgid;
391 else if (gid_eq(kgid, old->gid) || gid_eq(kgid, old->sgid))
392 new->egid = new->fsgid = kgid;
396 return commit_creds(new);
404 * change the user struct in a credentials set to match the new UID
406 static int set_user(struct cred *new)
408 struct user_struct *new_user;
410 new_user = alloc_uid(new->uid);
415 * We don't fail in case of NPROC limit excess here because too many
416 * poorly written programs don't check set*uid() return code, assuming
417 * it never fails if called by root. We may still enforce NPROC limit
418 * for programs doing set*uid()+execve() by harmlessly deferring the
419 * failure to the execve() stage.
421 if (atomic_read(&new_user->processes) >= rlimit(RLIMIT_NPROC) &&
422 new_user != INIT_USER)
423 current->flags |= PF_NPROC_EXCEEDED;
425 current->flags &= ~PF_NPROC_EXCEEDED;
428 new->user = new_user;
433 * Unprivileged users may change the real uid to the effective uid
434 * or vice versa. (BSD-style)
436 * If you set the real uid at all, or set the effective uid to a value not
437 * equal to the real uid, then the saved uid is set to the new effective uid.
439 * This makes it possible for a setuid program to completely drop its
440 * privileges, which is often a useful assertion to make when you are doing
441 * a security audit over a program.
443 * The general idea is that a program which uses just setreuid() will be
444 * 100% compatible with BSD. A program which uses just setuid() will be
445 * 100% compatible with POSIX with saved IDs.
447 SYSCALL_DEFINE2(setreuid, uid_t, ruid, uid_t, euid)
449 struct user_namespace *ns = current_user_ns();
450 const struct cred *old;
455 kruid = make_kuid(ns, ruid);
456 keuid = make_kuid(ns, euid);
458 if ((ruid != (uid_t) -1) && !uid_valid(kruid))
460 if ((euid != (uid_t) -1) && !uid_valid(keuid))
463 new = prepare_creds();
466 old = current_cred();
469 if (ruid != (uid_t) -1) {
471 if (!uid_eq(old->uid, kruid) &&
472 !uid_eq(old->euid, kruid) &&
473 !ns_capable(old->user_ns, CAP_SETUID))
477 if (euid != (uid_t) -1) {
479 if (!uid_eq(old->uid, keuid) &&
480 !uid_eq(old->euid, keuid) &&
481 !uid_eq(old->suid, keuid) &&
482 !ns_capable(old->user_ns, CAP_SETUID))
486 if (!uid_eq(new->uid, old->uid)) {
487 retval = set_user(new);
491 if (ruid != (uid_t) -1 ||
492 (euid != (uid_t) -1 && !uid_eq(keuid, old->uid)))
493 new->suid = new->euid;
494 new->fsuid = new->euid;
496 retval = security_task_fix_setuid(new, old, LSM_SETID_RE);
500 return commit_creds(new);
508 * setuid() is implemented like SysV with SAVED_IDS
510 * Note that SAVED_ID's is deficient in that a setuid root program
511 * like sendmail, for example, cannot set its uid to be a normal
512 * user and then switch back, because if you're root, setuid() sets
513 * the saved uid too. If you don't like this, blame the bright people
514 * in the POSIX committee and/or USG. Note that the BSD-style setreuid()
515 * will allow a root program to temporarily drop privileges and be able to
516 * regain them by swapping the real and effective uid.
518 SYSCALL_DEFINE1(setuid, uid_t, uid)
520 struct user_namespace *ns = current_user_ns();
521 const struct cred *old;
526 kuid = make_kuid(ns, uid);
527 if (!uid_valid(kuid))
530 new = prepare_creds();
533 old = current_cred();
536 if (ns_capable(old->user_ns, CAP_SETUID)) {
537 new->suid = new->uid = kuid;
538 if (!uid_eq(kuid, old->uid)) {
539 retval = set_user(new);
543 } else if (!uid_eq(kuid, old->uid) && !uid_eq(kuid, new->suid)) {
547 new->fsuid = new->euid = kuid;
549 retval = security_task_fix_setuid(new, old, LSM_SETID_ID);
553 return commit_creds(new);
562 * This function implements a generic ability to update ruid, euid,
563 * and suid. This allows you to implement the 4.4 compatible seteuid().
565 SYSCALL_DEFINE3(setresuid, uid_t, ruid, uid_t, euid, uid_t, suid)
567 struct user_namespace *ns = current_user_ns();
568 const struct cred *old;
571 kuid_t kruid, keuid, ksuid;
573 kruid = make_kuid(ns, ruid);
574 keuid = make_kuid(ns, euid);
575 ksuid = make_kuid(ns, suid);
577 if ((ruid != (uid_t) -1) && !uid_valid(kruid))
580 if ((euid != (uid_t) -1) && !uid_valid(keuid))
583 if ((suid != (uid_t) -1) && !uid_valid(ksuid))
586 new = prepare_creds();
590 old = current_cred();
593 if (!ns_capable(old->user_ns, CAP_SETUID)) {
594 if (ruid != (uid_t) -1 && !uid_eq(kruid, old->uid) &&
595 !uid_eq(kruid, old->euid) && !uid_eq(kruid, old->suid))
597 if (euid != (uid_t) -1 && !uid_eq(keuid, old->uid) &&
598 !uid_eq(keuid, old->euid) && !uid_eq(keuid, old->suid))
600 if (suid != (uid_t) -1 && !uid_eq(ksuid, old->uid) &&
601 !uid_eq(ksuid, old->euid) && !uid_eq(ksuid, old->suid))
605 if (ruid != (uid_t) -1) {
607 if (!uid_eq(kruid, old->uid)) {
608 retval = set_user(new);
613 if (euid != (uid_t) -1)
615 if (suid != (uid_t) -1)
617 new->fsuid = new->euid;
619 retval = security_task_fix_setuid(new, old, LSM_SETID_RES);
623 return commit_creds(new);
630 SYSCALL_DEFINE3(getresuid, uid_t __user *, ruidp, uid_t __user *, euidp, uid_t __user *, suidp)
632 const struct cred *cred = current_cred();
634 uid_t ruid, euid, suid;
636 ruid = from_kuid_munged(cred->user_ns, cred->uid);
637 euid = from_kuid_munged(cred->user_ns, cred->euid);
638 suid = from_kuid_munged(cred->user_ns, cred->suid);
640 if (!(retval = put_user(ruid, ruidp)) &&
641 !(retval = put_user(euid, euidp)))
642 retval = put_user(suid, suidp);
648 * Same as above, but for rgid, egid, sgid.
650 SYSCALL_DEFINE3(setresgid, gid_t, rgid, gid_t, egid, gid_t, sgid)
652 struct user_namespace *ns = current_user_ns();
653 const struct cred *old;
656 kgid_t krgid, kegid, ksgid;
658 krgid = make_kgid(ns, rgid);
659 kegid = make_kgid(ns, egid);
660 ksgid = make_kgid(ns, sgid);
662 if ((rgid != (gid_t) -1) && !gid_valid(krgid))
664 if ((egid != (gid_t) -1) && !gid_valid(kegid))
666 if ((sgid != (gid_t) -1) && !gid_valid(ksgid))
669 new = prepare_creds();
672 old = current_cred();
675 if (!ns_capable(old->user_ns, CAP_SETGID)) {
676 if (rgid != (gid_t) -1 && !gid_eq(krgid, old->gid) &&
677 !gid_eq(krgid, old->egid) && !gid_eq(krgid, old->sgid))
679 if (egid != (gid_t) -1 && !gid_eq(kegid, old->gid) &&
680 !gid_eq(kegid, old->egid) && !gid_eq(kegid, old->sgid))
682 if (sgid != (gid_t) -1 && !gid_eq(ksgid, old->gid) &&
683 !gid_eq(ksgid, old->egid) && !gid_eq(ksgid, old->sgid))
687 if (rgid != (gid_t) -1)
689 if (egid != (gid_t) -1)
691 if (sgid != (gid_t) -1)
693 new->fsgid = new->egid;
695 return commit_creds(new);
702 SYSCALL_DEFINE3(getresgid, gid_t __user *, rgidp, gid_t __user *, egidp, gid_t __user *, sgidp)
704 const struct cred *cred = current_cred();
706 gid_t rgid, egid, sgid;
708 rgid = from_kgid_munged(cred->user_ns, cred->gid);
709 egid = from_kgid_munged(cred->user_ns, cred->egid);
710 sgid = from_kgid_munged(cred->user_ns, cred->sgid);
712 if (!(retval = put_user(rgid, rgidp)) &&
713 !(retval = put_user(egid, egidp)))
714 retval = put_user(sgid, sgidp);
721 * "setfsuid()" sets the fsuid - the uid used for filesystem checks. This
722 * is used for "access()" and for the NFS daemon (letting nfsd stay at
723 * whatever uid it wants to). It normally shadows "euid", except when
724 * explicitly set by setfsuid() or for access..
726 SYSCALL_DEFINE1(setfsuid, uid_t, uid)
728 const struct cred *old;
733 old = current_cred();
734 old_fsuid = from_kuid_munged(old->user_ns, old->fsuid);
736 kuid = make_kuid(old->user_ns, uid);
737 if (!uid_valid(kuid))
740 new = prepare_creds();
744 if (uid_eq(kuid, old->uid) || uid_eq(kuid, old->euid) ||
745 uid_eq(kuid, old->suid) || uid_eq(kuid, old->fsuid) ||
746 ns_capable(old->user_ns, CAP_SETUID)) {
747 if (!uid_eq(kuid, old->fsuid)) {
749 if (security_task_fix_setuid(new, old, LSM_SETID_FS) == 0)
763 * Samma på svenska..
765 SYSCALL_DEFINE1(setfsgid, gid_t, gid)
767 const struct cred *old;
772 old = current_cred();
773 old_fsgid = from_kgid_munged(old->user_ns, old->fsgid);
775 kgid = make_kgid(old->user_ns, gid);
776 if (!gid_valid(kgid))
779 new = prepare_creds();
783 if (gid_eq(kgid, old->gid) || gid_eq(kgid, old->egid) ||
784 gid_eq(kgid, old->sgid) || gid_eq(kgid, old->fsgid) ||
785 ns_capable(old->user_ns, CAP_SETGID)) {
786 if (!gid_eq(kgid, old->fsgid)) {
801 * sys_getpid - return the thread group id of the current process
803 * Note, despite the name, this returns the tgid not the pid. The tgid and
804 * the pid are identical unless CLONE_THREAD was specified on clone() in
805 * which case the tgid is the same in all threads of the same group.
807 * This is SMP safe as current->tgid does not change.
809 SYSCALL_DEFINE0(getpid)
811 return task_tgid_vnr(current);
814 /* Thread ID - the internal kernel "pid" */
815 SYSCALL_DEFINE0(gettid)
817 return task_pid_vnr(current);
821 * Accessing ->real_parent is not SMP-safe, it could
822 * change from under us. However, we can use a stale
823 * value of ->real_parent under rcu_read_lock(), see
824 * release_task()->call_rcu(delayed_put_task_struct).
826 SYSCALL_DEFINE0(getppid)
831 pid = task_tgid_vnr(rcu_dereference(current->real_parent));
837 SYSCALL_DEFINE0(getuid)
839 /* Only we change this so SMP safe */
840 return from_kuid_munged(current_user_ns(), current_uid());
843 SYSCALL_DEFINE0(geteuid)
845 /* Only we change this so SMP safe */
846 return from_kuid_munged(current_user_ns(), current_euid());
849 SYSCALL_DEFINE0(getgid)
851 /* Only we change this so SMP safe */
852 return from_kgid_munged(current_user_ns(), current_gid());
855 SYSCALL_DEFINE0(getegid)
857 /* Only we change this so SMP safe */
858 return from_kgid_munged(current_user_ns(), current_egid());
861 void do_sys_times(struct tms *tms)
863 cputime_t tgutime, tgstime, cutime, cstime;
865 spin_lock_irq(¤t->sighand->siglock);
866 thread_group_cputime_adjusted(current, &tgutime, &tgstime);
867 cutime = current->signal->cutime;
868 cstime = current->signal->cstime;
869 spin_unlock_irq(¤t->sighand->siglock);
870 tms->tms_utime = cputime_to_clock_t(tgutime);
871 tms->tms_stime = cputime_to_clock_t(tgstime);
872 tms->tms_cutime = cputime_to_clock_t(cutime);
873 tms->tms_cstime = cputime_to_clock_t(cstime);
876 SYSCALL_DEFINE1(times, struct tms __user *, tbuf)
882 if (copy_to_user(tbuf, &tmp, sizeof(struct tms)))
885 force_successful_syscall_return();
886 return (long) jiffies_64_to_clock_t(get_jiffies_64());
890 * This needs some heavy checking ...
891 * I just haven't the stomach for it. I also don't fully
892 * understand sessions/pgrp etc. Let somebody who does explain it.
894 * OK, I think I have the protection semantics right.... this is really
895 * only important on a multi-user system anyway, to make sure one user
896 * can't send a signal to a process owned by another. -TYT, 12/12/91
898 * !PF_FORKNOEXEC check to conform completely to POSIX.
900 SYSCALL_DEFINE2(setpgid, pid_t, pid, pid_t, pgid)
902 struct task_struct *p;
903 struct task_struct *group_leader = current->group_leader;
908 pid = task_pid_vnr(group_leader);
915 /* From this point forward we keep holding onto the tasklist lock
916 * so that our parent does not change from under us. -DaveM
918 write_lock_irq(&tasklist_lock);
921 p = find_task_by_vpid(pid);
926 if (!thread_group_leader(p))
929 if (same_thread_group(p->real_parent, group_leader)) {
931 if (task_session(p) != task_session(group_leader))
934 if (!(p->flags & PF_FORKNOEXEC))
938 if (p != group_leader)
943 if (p->signal->leader)
948 struct task_struct *g;
950 pgrp = find_vpid(pgid);
951 g = pid_task(pgrp, PIDTYPE_PGID);
952 if (!g || task_session(g) != task_session(group_leader))
956 err = security_task_setpgid(p, pgid);
960 if (task_pgrp(p) != pgrp)
961 change_pid(p, PIDTYPE_PGID, pgrp);
965 /* All paths lead to here, thus we are safe. -DaveM */
966 write_unlock_irq(&tasklist_lock);
971 SYSCALL_DEFINE1(getpgid, pid_t, pid)
973 struct task_struct *p;
979 grp = task_pgrp(current);
982 p = find_task_by_vpid(pid);
989 retval = security_task_getpgid(p);
993 retval = pid_vnr(grp);
999 #ifdef __ARCH_WANT_SYS_GETPGRP
1001 SYSCALL_DEFINE0(getpgrp)
1003 return sys_getpgid(0);
1008 SYSCALL_DEFINE1(getsid, pid_t, pid)
1010 struct task_struct *p;
1016 sid = task_session(current);
1019 p = find_task_by_vpid(pid);
1022 sid = task_session(p);
1026 retval = security_task_getsid(p);
1030 retval = pid_vnr(sid);
1036 static void set_special_pids(struct pid *pid)
1038 struct task_struct *curr = current->group_leader;
1040 if (task_session(curr) != pid)
1041 change_pid(curr, PIDTYPE_SID, pid);
1043 if (task_pgrp(curr) != pid)
1044 change_pid(curr, PIDTYPE_PGID, pid);
1047 SYSCALL_DEFINE0(setsid)
1049 struct task_struct *group_leader = current->group_leader;
1050 struct pid *sid = task_pid(group_leader);
1051 pid_t session = pid_vnr(sid);
1054 write_lock_irq(&tasklist_lock);
1055 /* Fail if I am already a session leader */
1056 if (group_leader->signal->leader)
1059 /* Fail if a process group id already exists that equals the
1060 * proposed session id.
1062 if (pid_task(sid, PIDTYPE_PGID))
1065 group_leader->signal->leader = 1;
1066 set_special_pids(sid);
1068 proc_clear_tty(group_leader);
1072 write_unlock_irq(&tasklist_lock);
1074 proc_sid_connector(group_leader);
1075 sched_autogroup_create_attach(group_leader);
1080 DECLARE_RWSEM(uts_sem);
1082 #ifdef COMPAT_UTS_MACHINE
1083 #define override_architecture(name) \
1084 (personality(current->personality) == PER_LINUX32 && \
1085 copy_to_user(name->machine, COMPAT_UTS_MACHINE, \
1086 sizeof(COMPAT_UTS_MACHINE)))
1088 #define override_architecture(name) 0
1092 * Work around broken programs that cannot handle "Linux 3.0".
1093 * Instead we map 3.x to 2.6.40+x, so e.g. 3.0 would be 2.6.40
1095 static int override_release(char __user *release, size_t len)
1099 if (current->personality & UNAME26) {
1100 const char *rest = UTS_RELEASE;
1101 char buf[65] = { 0 };
1107 if (*rest == '.' && ++ndots >= 3)
1109 if (!isdigit(*rest) && *rest != '.')
1113 v = ((LINUX_VERSION_CODE >> 8) & 0xff) + 40;
1114 copy = clamp_t(size_t, len, 1, sizeof(buf));
1115 copy = scnprintf(buf, copy, "2.6.%u%s", v, rest);
1116 ret = copy_to_user(release, buf, copy + 1);
1121 SYSCALL_DEFINE1(newuname, struct new_utsname __user *, name)
1125 down_read(&uts_sem);
1126 if (copy_to_user(name, utsname(), sizeof *name))
1130 if (!errno && override_release(name->release, sizeof(name->release)))
1132 if (!errno && override_architecture(name))
1137 #ifdef __ARCH_WANT_SYS_OLD_UNAME
1141 SYSCALL_DEFINE1(uname, struct old_utsname __user *, name)
1148 down_read(&uts_sem);
1149 if (copy_to_user(name, utsname(), sizeof(*name)))
1153 if (!error && override_release(name->release, sizeof(name->release)))
1155 if (!error && override_architecture(name))
1160 SYSCALL_DEFINE1(olduname, struct oldold_utsname __user *, name)
1166 if (!access_ok(VERIFY_WRITE, name, sizeof(struct oldold_utsname)))
1169 down_read(&uts_sem);
1170 error = __copy_to_user(&name->sysname, &utsname()->sysname,
1172 error |= __put_user(0, name->sysname + __OLD_UTS_LEN);
1173 error |= __copy_to_user(&name->nodename, &utsname()->nodename,
1175 error |= __put_user(0, name->nodename + __OLD_UTS_LEN);
1176 error |= __copy_to_user(&name->release, &utsname()->release,
1178 error |= __put_user(0, name->release + __OLD_UTS_LEN);
1179 error |= __copy_to_user(&name->version, &utsname()->version,
1181 error |= __put_user(0, name->version + __OLD_UTS_LEN);
1182 error |= __copy_to_user(&name->machine, &utsname()->machine,
1184 error |= __put_user(0, name->machine + __OLD_UTS_LEN);
1187 if (!error && override_architecture(name))
1189 if (!error && override_release(name->release, sizeof(name->release)))
1191 return error ? -EFAULT : 0;
1195 SYSCALL_DEFINE2(sethostname, char __user *, name, int, len)
1198 char tmp[__NEW_UTS_LEN];
1200 if (!ns_capable(current->nsproxy->uts_ns->user_ns, CAP_SYS_ADMIN))
1203 if (len < 0 || len > __NEW_UTS_LEN)
1205 down_write(&uts_sem);
1207 if (!copy_from_user(tmp, name, len)) {
1208 struct new_utsname *u = utsname();
1210 memcpy(u->nodename, tmp, len);
1211 memset(u->nodename + len, 0, sizeof(u->nodename) - len);
1213 uts_proc_notify(UTS_PROC_HOSTNAME);
1219 #ifdef __ARCH_WANT_SYS_GETHOSTNAME
1221 SYSCALL_DEFINE2(gethostname, char __user *, name, int, len)
1224 struct new_utsname *u;
1228 down_read(&uts_sem);
1230 i = 1 + strlen(u->nodename);
1234 if (copy_to_user(name, u->nodename, i))
1243 * Only setdomainname; getdomainname can be implemented by calling
1246 SYSCALL_DEFINE2(setdomainname, char __user *, name, int, len)
1249 char tmp[__NEW_UTS_LEN];
1251 if (!ns_capable(current->nsproxy->uts_ns->user_ns, CAP_SYS_ADMIN))
1253 if (len < 0 || len > __NEW_UTS_LEN)
1256 down_write(&uts_sem);
1258 if (!copy_from_user(tmp, name, len)) {
1259 struct new_utsname *u = utsname();
1261 memcpy(u->domainname, tmp, len);
1262 memset(u->domainname + len, 0, sizeof(u->domainname) - len);
1264 uts_proc_notify(UTS_PROC_DOMAINNAME);
1270 SYSCALL_DEFINE2(getrlimit, unsigned int, resource, struct rlimit __user *, rlim)
1272 struct rlimit value;
1275 ret = do_prlimit(current, resource, NULL, &value);
1277 ret = copy_to_user(rlim, &value, sizeof(*rlim)) ? -EFAULT : 0;
1282 #ifdef __ARCH_WANT_SYS_OLD_GETRLIMIT
1285 * Back compatibility for getrlimit. Needed for some apps.
1288 SYSCALL_DEFINE2(old_getrlimit, unsigned int, resource,
1289 struct rlimit __user *, rlim)
1292 if (resource >= RLIM_NLIMITS)
1295 task_lock(current->group_leader);
1296 x = current->signal->rlim[resource];
1297 task_unlock(current->group_leader);
1298 if (x.rlim_cur > 0x7FFFFFFF)
1299 x.rlim_cur = 0x7FFFFFFF;
1300 if (x.rlim_max > 0x7FFFFFFF)
1301 x.rlim_max = 0x7FFFFFFF;
1302 return copy_to_user(rlim, &x, sizeof(x))?-EFAULT:0;
1307 static inline bool rlim64_is_infinity(__u64 rlim64)
1309 #if BITS_PER_LONG < 64
1310 return rlim64 >= ULONG_MAX;
1312 return rlim64 == RLIM64_INFINITY;
1316 static void rlim_to_rlim64(const struct rlimit *rlim, struct rlimit64 *rlim64)
1318 if (rlim->rlim_cur == RLIM_INFINITY)
1319 rlim64->rlim_cur = RLIM64_INFINITY;
1321 rlim64->rlim_cur = rlim->rlim_cur;
1322 if (rlim->rlim_max == RLIM_INFINITY)
1323 rlim64->rlim_max = RLIM64_INFINITY;
1325 rlim64->rlim_max = rlim->rlim_max;
1328 static void rlim64_to_rlim(const struct rlimit64 *rlim64, struct rlimit *rlim)
1330 if (rlim64_is_infinity(rlim64->rlim_cur))
1331 rlim->rlim_cur = RLIM_INFINITY;
1333 rlim->rlim_cur = (unsigned long)rlim64->rlim_cur;
1334 if (rlim64_is_infinity(rlim64->rlim_max))
1335 rlim->rlim_max = RLIM_INFINITY;
1337 rlim->rlim_max = (unsigned long)rlim64->rlim_max;
1340 /* make sure you are allowed to change @tsk limits before calling this */
1341 int do_prlimit(struct task_struct *tsk, unsigned int resource,
1342 struct rlimit *new_rlim, struct rlimit *old_rlim)
1344 struct rlimit *rlim;
1347 if (resource >= RLIM_NLIMITS)
1350 if (new_rlim->rlim_cur > new_rlim->rlim_max)
1352 if (resource == RLIMIT_NOFILE &&
1353 new_rlim->rlim_max > sysctl_nr_open)
1357 /* protect tsk->signal and tsk->sighand from disappearing */
1358 read_lock(&tasklist_lock);
1359 if (!tsk->sighand) {
1364 rlim = tsk->signal->rlim + resource;
1365 task_lock(tsk->group_leader);
1367 /* Keep the capable check against init_user_ns until
1368 cgroups can contain all limits */
1369 if (new_rlim->rlim_max > rlim->rlim_max &&
1370 !capable(CAP_SYS_RESOURCE))
1373 retval = security_task_setrlimit(tsk->group_leader,
1374 resource, new_rlim);
1375 if (resource == RLIMIT_CPU && new_rlim->rlim_cur == 0) {
1377 * The caller is asking for an immediate RLIMIT_CPU
1378 * expiry. But we use the zero value to mean "it was
1379 * never set". So let's cheat and make it one second
1382 new_rlim->rlim_cur = 1;
1391 task_unlock(tsk->group_leader);
1394 * RLIMIT_CPU handling. Note that the kernel fails to return an error
1395 * code if it rejected the user's attempt to set RLIMIT_CPU. This is a
1396 * very long-standing error, and fixing it now risks breakage of
1397 * applications, so we live with it
1399 if (!retval && new_rlim && resource == RLIMIT_CPU &&
1400 new_rlim->rlim_cur != RLIM_INFINITY)
1401 update_rlimit_cpu(tsk, new_rlim->rlim_cur);
1403 read_unlock(&tasklist_lock);
1407 /* rcu lock must be held */
1408 static int check_prlimit_permission(struct task_struct *task)
1410 const struct cred *cred = current_cred(), *tcred;
1412 if (current == task)
1415 tcred = __task_cred(task);
1416 if (uid_eq(cred->uid, tcred->euid) &&
1417 uid_eq(cred->uid, tcred->suid) &&
1418 uid_eq(cred->uid, tcred->uid) &&
1419 gid_eq(cred->gid, tcred->egid) &&
1420 gid_eq(cred->gid, tcred->sgid) &&
1421 gid_eq(cred->gid, tcred->gid))
1423 if (ns_capable(tcred->user_ns, CAP_SYS_RESOURCE))
1429 SYSCALL_DEFINE4(prlimit64, pid_t, pid, unsigned int, resource,
1430 const struct rlimit64 __user *, new_rlim,
1431 struct rlimit64 __user *, old_rlim)
1433 struct rlimit64 old64, new64;
1434 struct rlimit old, new;
1435 struct task_struct *tsk;
1439 if (copy_from_user(&new64, new_rlim, sizeof(new64)))
1441 rlim64_to_rlim(&new64, &new);
1445 tsk = pid ? find_task_by_vpid(pid) : current;
1450 ret = check_prlimit_permission(tsk);
1455 get_task_struct(tsk);
1458 ret = do_prlimit(tsk, resource, new_rlim ? &new : NULL,
1459 old_rlim ? &old : NULL);
1461 if (!ret && old_rlim) {
1462 rlim_to_rlim64(&old, &old64);
1463 if (copy_to_user(old_rlim, &old64, sizeof(old64)))
1467 put_task_struct(tsk);
1471 SYSCALL_DEFINE2(setrlimit, unsigned int, resource, struct rlimit __user *, rlim)
1473 struct rlimit new_rlim;
1475 if (copy_from_user(&new_rlim, rlim, sizeof(*rlim)))
1477 return do_prlimit(current, resource, &new_rlim, NULL);
1481 * It would make sense to put struct rusage in the task_struct,
1482 * except that would make the task_struct be *really big*. After
1483 * task_struct gets moved into malloc'ed memory, it would
1484 * make sense to do this. It will make moving the rest of the information
1485 * a lot simpler! (Which we're not doing right now because we're not
1486 * measuring them yet).
1488 * When sampling multiple threads for RUSAGE_SELF, under SMP we might have
1489 * races with threads incrementing their own counters. But since word
1490 * reads are atomic, we either get new values or old values and we don't
1491 * care which for the sums. We always take the siglock to protect reading
1492 * the c* fields from p->signal from races with exit.c updating those
1493 * fields when reaping, so a sample either gets all the additions of a
1494 * given child after it's reaped, or none so this sample is before reaping.
1497 * We need to take the siglock for CHILDEREN, SELF and BOTH
1498 * for the cases current multithreaded, non-current single threaded
1499 * non-current multithreaded. Thread traversal is now safe with
1501 * Strictly speaking, we donot need to take the siglock if we are current and
1502 * single threaded, as no one else can take our signal_struct away, no one
1503 * else can reap the children to update signal->c* counters, and no one else
1504 * can race with the signal-> fields. If we do not take any lock, the
1505 * signal-> fields could be read out of order while another thread was just
1506 * exiting. So we should place a read memory barrier when we avoid the lock.
1507 * On the writer side, write memory barrier is implied in __exit_signal
1508 * as __exit_signal releases the siglock spinlock after updating the signal->
1509 * fields. But we don't do this yet to keep things simple.
1513 static void accumulate_thread_rusage(struct task_struct *t, struct rusage *r)
1515 r->ru_nvcsw += t->nvcsw;
1516 r->ru_nivcsw += t->nivcsw;
1517 r->ru_minflt += t->min_flt;
1518 r->ru_majflt += t->maj_flt;
1519 r->ru_inblock += task_io_get_inblock(t);
1520 r->ru_oublock += task_io_get_oublock(t);
1523 static void k_getrusage(struct task_struct *p, int who, struct rusage *r)
1525 struct task_struct *t;
1526 unsigned long flags;
1527 cputime_t tgutime, tgstime, utime, stime;
1528 unsigned long maxrss = 0;
1530 memset((char *) r, 0, sizeof *r);
1533 if (who == RUSAGE_THREAD) {
1534 task_cputime_adjusted(current, &utime, &stime);
1535 accumulate_thread_rusage(p, r);
1536 maxrss = p->signal->maxrss;
1540 if (!lock_task_sighand(p, &flags))
1545 case RUSAGE_CHILDREN:
1546 utime = p->signal->cutime;
1547 stime = p->signal->cstime;
1548 r->ru_nvcsw = p->signal->cnvcsw;
1549 r->ru_nivcsw = p->signal->cnivcsw;
1550 r->ru_minflt = p->signal->cmin_flt;
1551 r->ru_majflt = p->signal->cmaj_flt;
1552 r->ru_inblock = p->signal->cinblock;
1553 r->ru_oublock = p->signal->coublock;
1554 maxrss = p->signal->cmaxrss;
1556 if (who == RUSAGE_CHILDREN)
1560 thread_group_cputime_adjusted(p, &tgutime, &tgstime);
1563 r->ru_nvcsw += p->signal->nvcsw;
1564 r->ru_nivcsw += p->signal->nivcsw;
1565 r->ru_minflt += p->signal->min_flt;
1566 r->ru_majflt += p->signal->maj_flt;
1567 r->ru_inblock += p->signal->inblock;
1568 r->ru_oublock += p->signal->oublock;
1569 if (maxrss < p->signal->maxrss)
1570 maxrss = p->signal->maxrss;
1573 accumulate_thread_rusage(t, r);
1574 } while_each_thread(p, t);
1580 unlock_task_sighand(p, &flags);
1583 cputime_to_timeval(utime, &r->ru_utime);
1584 cputime_to_timeval(stime, &r->ru_stime);
1586 if (who != RUSAGE_CHILDREN) {
1587 struct mm_struct *mm = get_task_mm(p);
1589 setmax_mm_hiwater_rss(&maxrss, mm);
1593 r->ru_maxrss = maxrss * (PAGE_SIZE / 1024); /* convert pages to KBs */
1596 int getrusage(struct task_struct *p, int who, struct rusage __user *ru)
1599 k_getrusage(p, who, &r);
1600 return copy_to_user(ru, &r, sizeof(r)) ? -EFAULT : 0;
1603 SYSCALL_DEFINE2(getrusage, int, who, struct rusage __user *, ru)
1605 if (who != RUSAGE_SELF && who != RUSAGE_CHILDREN &&
1606 who != RUSAGE_THREAD)
1608 return getrusage(current, who, ru);
1611 #ifdef CONFIG_COMPAT
1612 COMPAT_SYSCALL_DEFINE2(getrusage, int, who, struct compat_rusage __user *, ru)
1616 if (who != RUSAGE_SELF && who != RUSAGE_CHILDREN &&
1617 who != RUSAGE_THREAD)
1620 k_getrusage(current, who, &r);
1621 return put_compat_rusage(&r, ru);
1625 SYSCALL_DEFINE1(umask, int, mask)
1627 mask = xchg(¤t->fs->umask, mask & S_IRWXUGO);
1631 static int prctl_set_mm_exe_file(struct mm_struct *mm, unsigned int fd)
1634 struct inode *inode;
1641 inode = file_inode(exe.file);
1644 * Because the original mm->exe_file points to executable file, make
1645 * sure that this one is executable as well, to avoid breaking an
1649 if (!S_ISREG(inode->i_mode) ||
1650 exe.file->f_path.mnt->mnt_flags & MNT_NOEXEC)
1653 err = inode_permission(inode, MAY_EXEC);
1657 down_write(&mm->mmap_sem);
1660 * Forbid mm->exe_file change if old file still mapped.
1664 struct vm_area_struct *vma;
1666 for (vma = mm->mmap; vma; vma = vma->vm_next)
1668 path_equal(&vma->vm_file->f_path,
1669 &mm->exe_file->f_path))
1674 * The symlink can be changed only once, just to disallow arbitrary
1675 * transitions malicious software might bring in. This means one
1676 * could make a snapshot over all processes running and monitor
1677 * /proc/pid/exe changes to notice unusual activity if needed.
1680 if (test_and_set_bit(MMF_EXE_FILE_CHANGED, &mm->flags))
1684 set_mm_exe_file(mm, exe.file); /* this grabs a reference to exe.file */
1686 up_write(&mm->mmap_sem);
1693 static int prctl_set_mm(int opt, unsigned long addr,
1694 unsigned long arg4, unsigned long arg5)
1696 unsigned long rlim = rlimit(RLIMIT_DATA);
1697 struct mm_struct *mm = current->mm;
1698 struct vm_area_struct *vma;
1701 if (arg5 || (arg4 && opt != PR_SET_MM_AUXV))
1704 if (!capable(CAP_SYS_RESOURCE))
1707 if (opt == PR_SET_MM_EXE_FILE)
1708 return prctl_set_mm_exe_file(mm, (unsigned int)addr);
1710 if (addr >= TASK_SIZE || addr < mmap_min_addr)
1715 down_read(&mm->mmap_sem);
1716 vma = find_vma(mm, addr);
1719 case PR_SET_MM_START_CODE:
1720 mm->start_code = addr;
1722 case PR_SET_MM_END_CODE:
1723 mm->end_code = addr;
1725 case PR_SET_MM_START_DATA:
1726 mm->start_data = addr;
1728 case PR_SET_MM_END_DATA:
1729 mm->end_data = addr;
1732 case PR_SET_MM_START_BRK:
1733 if (addr <= mm->end_data)
1736 if (rlim < RLIM_INFINITY &&
1738 (mm->end_data - mm->start_data) > rlim)
1741 mm->start_brk = addr;
1745 if (addr <= mm->end_data)
1748 if (rlim < RLIM_INFINITY &&
1749 (addr - mm->start_brk) +
1750 (mm->end_data - mm->start_data) > rlim)
1757 * If command line arguments and environment
1758 * are placed somewhere else on stack, we can
1759 * set them up here, ARG_START/END to setup
1760 * command line argumets and ENV_START/END
1763 case PR_SET_MM_START_STACK:
1764 case PR_SET_MM_ARG_START:
1765 case PR_SET_MM_ARG_END:
1766 case PR_SET_MM_ENV_START:
1767 case PR_SET_MM_ENV_END:
1772 if (opt == PR_SET_MM_START_STACK)
1773 mm->start_stack = addr;
1774 else if (opt == PR_SET_MM_ARG_START)
1775 mm->arg_start = addr;
1776 else if (opt == PR_SET_MM_ARG_END)
1778 else if (opt == PR_SET_MM_ENV_START)
1779 mm->env_start = addr;
1780 else if (opt == PR_SET_MM_ENV_END)
1785 * This doesn't move auxiliary vector itself
1786 * since it's pinned to mm_struct, but allow
1787 * to fill vector with new values. It's up
1788 * to a caller to provide sane values here
1789 * otherwise user space tools which use this
1790 * vector might be unhappy.
1792 case PR_SET_MM_AUXV: {
1793 unsigned long user_auxv[AT_VECTOR_SIZE];
1795 if (arg4 > sizeof(user_auxv))
1797 up_read(&mm->mmap_sem);
1799 if (copy_from_user(user_auxv, (const void __user *)addr, arg4))
1802 /* Make sure the last entry is always AT_NULL */
1803 user_auxv[AT_VECTOR_SIZE - 2] = 0;
1804 user_auxv[AT_VECTOR_SIZE - 1] = 0;
1806 BUILD_BUG_ON(sizeof(user_auxv) != sizeof(mm->saved_auxv));
1809 memcpy(mm->saved_auxv, user_auxv, arg4);
1810 task_unlock(current);
1820 up_read(&mm->mmap_sem);
1824 #ifdef CONFIG_CHECKPOINT_RESTORE
1825 static int prctl_get_tid_address(struct task_struct *me, int __user **tid_addr)
1827 return put_user(me->clear_child_tid, tid_addr);
1830 static int prctl_get_tid_address(struct task_struct *me, int __user **tid_addr)
1836 SYSCALL_DEFINE5(prctl, int, option, unsigned long, arg2, unsigned long, arg3,
1837 unsigned long, arg4, unsigned long, arg5)
1839 struct task_struct *me = current;
1840 unsigned char comm[sizeof(me->comm)];
1843 error = security_task_prctl(option, arg2, arg3, arg4, arg5);
1844 if (error != -ENOSYS)
1849 case PR_SET_PDEATHSIG:
1850 if (!valid_signal(arg2)) {
1854 me->pdeath_signal = arg2;
1856 case PR_GET_PDEATHSIG:
1857 error = put_user(me->pdeath_signal, (int __user *)arg2);
1859 case PR_GET_DUMPABLE:
1860 error = get_dumpable(me->mm);
1862 case PR_SET_DUMPABLE:
1863 if (arg2 != SUID_DUMP_DISABLE && arg2 != SUID_DUMP_USER) {
1867 set_dumpable(me->mm, arg2);
1870 case PR_SET_UNALIGN:
1871 error = SET_UNALIGN_CTL(me, arg2);
1873 case PR_GET_UNALIGN:
1874 error = GET_UNALIGN_CTL(me, arg2);
1877 error = SET_FPEMU_CTL(me, arg2);
1880 error = GET_FPEMU_CTL(me, arg2);
1883 error = SET_FPEXC_CTL(me, arg2);
1886 error = GET_FPEXC_CTL(me, arg2);
1889 error = PR_TIMING_STATISTICAL;
1892 if (arg2 != PR_TIMING_STATISTICAL)
1896 comm[sizeof(me->comm) - 1] = 0;
1897 if (strncpy_from_user(comm, (char __user *)arg2,
1898 sizeof(me->comm) - 1) < 0)
1900 set_task_comm(me, comm);
1901 proc_comm_connector(me);
1904 get_task_comm(comm, me);
1905 if (copy_to_user((char __user *)arg2, comm, sizeof(comm)))
1909 error = GET_ENDIAN(me, arg2);
1912 error = SET_ENDIAN(me, arg2);
1914 case PR_GET_SECCOMP:
1915 error = prctl_get_seccomp();
1917 case PR_SET_SECCOMP:
1918 error = prctl_set_seccomp(arg2, (char __user *)arg3);
1921 error = GET_TSC_CTL(arg2);
1924 error = SET_TSC_CTL(arg2);
1926 case PR_TASK_PERF_EVENTS_DISABLE:
1927 error = perf_event_task_disable();
1929 case PR_TASK_PERF_EVENTS_ENABLE:
1930 error = perf_event_task_enable();
1932 case PR_GET_TIMERSLACK:
1933 error = current->timer_slack_ns;
1935 case PR_SET_TIMERSLACK:
1937 current->timer_slack_ns =
1938 current->default_timer_slack_ns;
1940 current->timer_slack_ns = arg2;
1946 case PR_MCE_KILL_CLEAR:
1949 current->flags &= ~PF_MCE_PROCESS;
1951 case PR_MCE_KILL_SET:
1952 current->flags |= PF_MCE_PROCESS;
1953 if (arg3 == PR_MCE_KILL_EARLY)
1954 current->flags |= PF_MCE_EARLY;
1955 else if (arg3 == PR_MCE_KILL_LATE)
1956 current->flags &= ~PF_MCE_EARLY;
1957 else if (arg3 == PR_MCE_KILL_DEFAULT)
1959 ~(PF_MCE_EARLY|PF_MCE_PROCESS);
1967 case PR_MCE_KILL_GET:
1968 if (arg2 | arg3 | arg4 | arg5)
1970 if (current->flags & PF_MCE_PROCESS)
1971 error = (current->flags & PF_MCE_EARLY) ?
1972 PR_MCE_KILL_EARLY : PR_MCE_KILL_LATE;
1974 error = PR_MCE_KILL_DEFAULT;
1977 error = prctl_set_mm(arg2, arg3, arg4, arg5);
1979 case PR_GET_TID_ADDRESS:
1980 error = prctl_get_tid_address(me, (int __user **)arg2);
1982 case PR_SET_CHILD_SUBREAPER:
1983 me->signal->is_child_subreaper = !!arg2;
1985 case PR_GET_CHILD_SUBREAPER:
1986 error = put_user(me->signal->is_child_subreaper,
1987 (int __user *)arg2);
1989 case PR_SET_NO_NEW_PRIVS:
1990 if (arg2 != 1 || arg3 || arg4 || arg5)
1993 task_set_no_new_privs(current);
1995 case PR_GET_NO_NEW_PRIVS:
1996 if (arg2 || arg3 || arg4 || arg5)
1998 return task_no_new_privs(current) ? 1 : 0;
1999 case PR_GET_THP_DISABLE:
2000 if (arg2 || arg3 || arg4 || arg5)
2002 error = !!(me->mm->def_flags & VM_NOHUGEPAGE);
2004 case PR_SET_THP_DISABLE:
2005 if (arg3 || arg4 || arg5)
2007 down_write(&me->mm->mmap_sem);
2009 me->mm->def_flags |= VM_NOHUGEPAGE;
2011 me->mm->def_flags &= ~VM_NOHUGEPAGE;
2012 up_write(&me->mm->mmap_sem);
2021 SYSCALL_DEFINE3(getcpu, unsigned __user *, cpup, unsigned __user *, nodep,
2022 struct getcpu_cache __user *, unused)
2025 int cpu = raw_smp_processor_id();
2027 err |= put_user(cpu, cpup);
2029 err |= put_user(cpu_to_node(cpu), nodep);
2030 return err ? -EFAULT : 0;
2034 * do_sysinfo - fill in sysinfo struct
2035 * @info: pointer to buffer to fill
2037 static int do_sysinfo(struct sysinfo *info)
2039 unsigned long mem_total, sav_total;
2040 unsigned int mem_unit, bitcount;
2043 memset(info, 0, sizeof(struct sysinfo));
2045 get_monotonic_boottime(&tp);
2046 info->uptime = tp.tv_sec + (tp.tv_nsec ? 1 : 0);
2048 get_avenrun(info->loads, 0, SI_LOAD_SHIFT - FSHIFT);
2050 info->procs = nr_threads;
2056 * If the sum of all the available memory (i.e. ram + swap)
2057 * is less than can be stored in a 32 bit unsigned long then
2058 * we can be binary compatible with 2.2.x kernels. If not,
2059 * well, in that case 2.2.x was broken anyways...
2061 * -Erik Andersen <andersee@debian.org>
2064 mem_total = info->totalram + info->totalswap;
2065 if (mem_total < info->totalram || mem_total < info->totalswap)
2068 mem_unit = info->mem_unit;
2069 while (mem_unit > 1) {
2072 sav_total = mem_total;
2074 if (mem_total < sav_total)
2079 * If mem_total did not overflow, multiply all memory values by
2080 * info->mem_unit and set it to 1. This leaves things compatible
2081 * with 2.2.x, and also retains compatibility with earlier 2.4.x
2086 info->totalram <<= bitcount;
2087 info->freeram <<= bitcount;
2088 info->sharedram <<= bitcount;
2089 info->bufferram <<= bitcount;
2090 info->totalswap <<= bitcount;
2091 info->freeswap <<= bitcount;
2092 info->totalhigh <<= bitcount;
2093 info->freehigh <<= bitcount;
2099 SYSCALL_DEFINE1(sysinfo, struct sysinfo __user *, info)
2105 if (copy_to_user(info, &val, sizeof(struct sysinfo)))
2111 #ifdef CONFIG_COMPAT
2112 struct compat_sysinfo {
2126 char _f[20-2*sizeof(u32)-sizeof(int)];
2129 COMPAT_SYSCALL_DEFINE1(sysinfo, struct compat_sysinfo __user *, info)
2135 /* Check to see if any memory value is too large for 32-bit and scale
2138 if ((s.totalram >> 32) || (s.totalswap >> 32)) {
2141 while (s.mem_unit < PAGE_SIZE) {
2146 s.totalram >>= bitcount;
2147 s.freeram >>= bitcount;
2148 s.sharedram >>= bitcount;
2149 s.bufferram >>= bitcount;
2150 s.totalswap >>= bitcount;
2151 s.freeswap >>= bitcount;
2152 s.totalhigh >>= bitcount;
2153 s.freehigh >>= bitcount;
2156 if (!access_ok(VERIFY_WRITE, info, sizeof(struct compat_sysinfo)) ||
2157 __put_user(s.uptime, &info->uptime) ||
2158 __put_user(s.loads[0], &info->loads[0]) ||
2159 __put_user(s.loads[1], &info->loads[1]) ||
2160 __put_user(s.loads[2], &info->loads[2]) ||
2161 __put_user(s.totalram, &info->totalram) ||
2162 __put_user(s.freeram, &info->freeram) ||
2163 __put_user(s.sharedram, &info->sharedram) ||
2164 __put_user(s.bufferram, &info->bufferram) ||
2165 __put_user(s.totalswap, &info->totalswap) ||
2166 __put_user(s.freeswap, &info->freeswap) ||
2167 __put_user(s.procs, &info->procs) ||
2168 __put_user(s.totalhigh, &info->totalhigh) ||
2169 __put_user(s.freehigh, &info->freehigh) ||
2170 __put_user(s.mem_unit, &info->mem_unit))
2175 #endif /* CONFIG_COMPAT */