v4.19.13 snapshot.
diff --git a/kernel/sys.c b/kernel/sys.c
new file mode 100644
index 0000000..123bd73
--- /dev/null
+++ b/kernel/sys.c
@@ -0,0 +1,2641 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * linux/kernel/sys.c
+ *
+ * Copyright (C) 1991, 1992 Linus Torvalds
+ */
+
+#include <linux/export.h>
+#include <linux/mm.h>
+#include <linux/utsname.h>
+#include <linux/mman.h>
+#include <linux/reboot.h>
+#include <linux/prctl.h>
+#include <linux/highuid.h>
+#include <linux/fs.h>
+#include <linux/kmod.h>
+#include <linux/perf_event.h>
+#include <linux/resource.h>
+#include <linux/kernel.h>
+#include <linux/workqueue.h>
+#include <linux/capability.h>
+#include <linux/device.h>
+#include <linux/key.h>
+#include <linux/times.h>
+#include <linux/posix-timers.h>
+#include <linux/security.h>
+#include <linux/dcookies.h>
+#include <linux/suspend.h>
+#include <linux/tty.h>
+#include <linux/signal.h>
+#include <linux/cn_proc.h>
+#include <linux/getcpu.h>
+#include <linux/task_io_accounting_ops.h>
+#include <linux/seccomp.h>
+#include <linux/cpu.h>
+#include <linux/personality.h>
+#include <linux/ptrace.h>
+#include <linux/fs_struct.h>
+#include <linux/file.h>
+#include <linux/mount.h>
+#include <linux/gfp.h>
+#include <linux/syscore_ops.h>
+#include <linux/version.h>
+#include <linux/ctype.h>
+
+#include <linux/compat.h>
+#include <linux/syscalls.h>
+#include <linux/kprobes.h>
+#include <linux/user_namespace.h>
+#include <linux/binfmts.h>
+
+#include <linux/sched.h>
+#include <linux/sched/autogroup.h>
+#include <linux/sched/loadavg.h>
+#include <linux/sched/stat.h>
+#include <linux/sched/mm.h>
+#include <linux/sched/coredump.h>
+#include <linux/sched/task.h>
+#include <linux/sched/cputime.h>
+#include <linux/rcupdate.h>
+#include <linux/uidgid.h>
+#include <linux/cred.h>
+
+#include <linux/nospec.h>
+
+#include <linux/kmsg_dump.h>
+/* Move somewhere else to avoid recompiling? */
+#include <generated/utsrelease.h>
+
+#include <linux/uaccess.h>
+#include <asm/io.h>
+#include <asm/unistd.h>
+
+#include "uid16.h"
+
+#ifndef SET_UNALIGN_CTL
+# define SET_UNALIGN_CTL(a, b) (-EINVAL)
+#endif
+#ifndef GET_UNALIGN_CTL
+# define GET_UNALIGN_CTL(a, b) (-EINVAL)
+#endif
+#ifndef SET_FPEMU_CTL
+# define SET_FPEMU_CTL(a, b) (-EINVAL)
+#endif
+#ifndef GET_FPEMU_CTL
+# define GET_FPEMU_CTL(a, b) (-EINVAL)
+#endif
+#ifndef SET_FPEXC_CTL
+# define SET_FPEXC_CTL(a, b) (-EINVAL)
+#endif
+#ifndef GET_FPEXC_CTL
+# define GET_FPEXC_CTL(a, b) (-EINVAL)
+#endif
+#ifndef GET_ENDIAN
+# define GET_ENDIAN(a, b) (-EINVAL)
+#endif
+#ifndef SET_ENDIAN
+# define SET_ENDIAN(a, b) (-EINVAL)
+#endif
+#ifndef GET_TSC_CTL
+# define GET_TSC_CTL(a) (-EINVAL)
+#endif
+#ifndef SET_TSC_CTL
+# define SET_TSC_CTL(a) (-EINVAL)
+#endif
+#ifndef MPX_ENABLE_MANAGEMENT
+# define MPX_ENABLE_MANAGEMENT() (-EINVAL)
+#endif
+#ifndef MPX_DISABLE_MANAGEMENT
+# define MPX_DISABLE_MANAGEMENT() (-EINVAL)
+#endif
+#ifndef GET_FP_MODE
+# define GET_FP_MODE(a) (-EINVAL)
+#endif
+#ifndef SET_FP_MODE
+# define SET_FP_MODE(a,b) (-EINVAL)
+#endif
+#ifndef SVE_SET_VL
+# define SVE_SET_VL(a) (-EINVAL)
+#endif
+#ifndef SVE_GET_VL
+# define SVE_GET_VL() (-EINVAL)
+#endif
+
+/*
+ * this is where the system-wide overflow UID and GID are defined, for
+ * architectures that now have 32-bit UID/GID but didn't in the past
+ */
+
+int overflowuid = DEFAULT_OVERFLOWUID;
+int overflowgid = DEFAULT_OVERFLOWGID;
+
+EXPORT_SYMBOL(overflowuid);
+EXPORT_SYMBOL(overflowgid);
+
+/*
+ * the same as above, but for filesystems which can only store a 16-bit
+ * UID and GID. as such, this is needed on all architectures
+ */
+
+int fs_overflowuid = DEFAULT_FS_OVERFLOWUID;
+int fs_overflowgid = DEFAULT_FS_OVERFLOWGID;
+
+EXPORT_SYMBOL(fs_overflowuid);
+EXPORT_SYMBOL(fs_overflowgid);
+
+/*
+ * Returns true if current's euid is same as p's uid or euid,
+ * or has CAP_SYS_NICE to p's user_ns.
+ *
+ * Called with rcu_read_lock, creds are safe
+ */
+static bool set_one_prio_perm(struct task_struct *p)
+{
+ const struct cred *cred = current_cred(), *pcred = __task_cred(p);
+
+ if (uid_eq(pcred->uid, cred->euid) ||
+ uid_eq(pcred->euid, cred->euid))
+ return true;
+ if (ns_capable(pcred->user_ns, CAP_SYS_NICE))
+ return true;
+ return false;
+}
+
+/*
+ * set the priority of a task
+ * - the caller must hold the RCU read lock
+ */
+static int set_one_prio(struct task_struct *p, int niceval, int error)
+{
+ int no_nice;
+
+ if (!set_one_prio_perm(p)) {
+ error = -EPERM;
+ goto out;
+ }
+ if (niceval < task_nice(p) && !can_nice(p, niceval)) {
+ error = -EACCES;
+ goto out;
+ }
+ no_nice = security_task_setnice(p, niceval);
+ if (no_nice) {
+ error = no_nice;
+ goto out;
+ }
+ if (error == -ESRCH)
+ error = 0;
+ set_user_nice(p, niceval);
+out:
+ return error;
+}
+
+SYSCALL_DEFINE3(setpriority, int, which, int, who, int, niceval)
+{
+ struct task_struct *g, *p;
+ struct user_struct *user;
+ const struct cred *cred = current_cred();
+ int error = -EINVAL;
+ struct pid *pgrp;
+ kuid_t uid;
+
+ if (which > PRIO_USER || which < PRIO_PROCESS)
+ goto out;
+
+ /* normalize: avoid signed division (rounding problems) */
+ error = -ESRCH;
+ if (niceval < MIN_NICE)
+ niceval = MIN_NICE;
+ if (niceval > MAX_NICE)
+ niceval = MAX_NICE;
+
+ rcu_read_lock();
+ read_lock(&tasklist_lock);
+ switch (which) {
+ case PRIO_PROCESS:
+ if (who)
+ p = find_task_by_vpid(who);
+ else
+ p = current;
+ if (p)
+ error = set_one_prio(p, niceval, error);
+ break;
+ case PRIO_PGRP:
+ if (who)
+ pgrp = find_vpid(who);
+ else
+ pgrp = task_pgrp(current);
+ do_each_pid_thread(pgrp, PIDTYPE_PGID, p) {
+ error = set_one_prio(p, niceval, error);
+ } while_each_pid_thread(pgrp, PIDTYPE_PGID, p);
+ break;
+ case PRIO_USER:
+ uid = make_kuid(cred->user_ns, who);
+ user = cred->user;
+ if (!who)
+ uid = cred->uid;
+ else if (!uid_eq(uid, cred->uid)) {
+ user = find_user(uid);
+ if (!user)
+ goto out_unlock; /* No processes for this user */
+ }
+ do_each_thread(g, p) {
+ if (uid_eq(task_uid(p), uid) && task_pid_vnr(p))
+ error = set_one_prio(p, niceval, error);
+ } while_each_thread(g, p);
+ if (!uid_eq(uid, cred->uid))
+ free_uid(user); /* For find_user() */
+ break;
+ }
+out_unlock:
+ read_unlock(&tasklist_lock);
+ rcu_read_unlock();
+out:
+ return error;
+}
+
+/*
+ * Ugh. To avoid negative return values, "getpriority()" will
+ * not return the normal nice-value, but a negated value that
+ * has been offset by 20 (ie it returns 40..1 instead of -20..19)
+ * to stay compatible.
+ */
+SYSCALL_DEFINE2(getpriority, int, which, int, who)
+{
+ struct task_struct *g, *p;
+ struct user_struct *user;
+ const struct cred *cred = current_cred();
+ long niceval, retval = -ESRCH;
+ struct pid *pgrp;
+ kuid_t uid;
+
+ if (which > PRIO_USER || which < PRIO_PROCESS)
+ return -EINVAL;
+
+ rcu_read_lock();
+ read_lock(&tasklist_lock);
+ switch (which) {
+ case PRIO_PROCESS:
+ if (who)
+ p = find_task_by_vpid(who);
+ else
+ p = current;
+ if (p) {
+ niceval = nice_to_rlimit(task_nice(p));
+ if (niceval > retval)
+ retval = niceval;
+ }
+ break;
+ case PRIO_PGRP:
+ if (who)
+ pgrp = find_vpid(who);
+ else
+ pgrp = task_pgrp(current);
+ do_each_pid_thread(pgrp, PIDTYPE_PGID, p) {
+ niceval = nice_to_rlimit(task_nice(p));
+ if (niceval > retval)
+ retval = niceval;
+ } while_each_pid_thread(pgrp, PIDTYPE_PGID, p);
+ break;
+ case PRIO_USER:
+ uid = make_kuid(cred->user_ns, who);
+ user = cred->user;
+ if (!who)
+ uid = cred->uid;
+ else if (!uid_eq(uid, cred->uid)) {
+ user = find_user(uid);
+ if (!user)
+ goto out_unlock; /* No processes for this user */
+ }
+ do_each_thread(g, p) {
+ if (uid_eq(task_uid(p), uid) && task_pid_vnr(p)) {
+ niceval = nice_to_rlimit(task_nice(p));
+ if (niceval > retval)
+ retval = niceval;
+ }
+ } while_each_thread(g, p);
+ if (!uid_eq(uid, cred->uid))
+ free_uid(user); /* for find_user() */
+ break;
+ }
+out_unlock:
+ read_unlock(&tasklist_lock);
+ rcu_read_unlock();
+
+ return retval;
+}
+
+/*
+ * Unprivileged users may change the real gid to the effective gid
+ * or vice versa. (BSD-style)
+ *
+ * If you set the real gid at all, or set the effective gid to a value not
+ * equal to the real gid, then the saved gid is set to the new effective gid.
+ *
+ * This makes it possible for a setgid program to completely drop its
+ * privileges, which is often a useful assertion to make when you are doing
+ * a security audit over a program.
+ *
+ * The general idea is that a program which uses just setregid() will be
+ * 100% compatible with BSD. A program which uses just setgid() will be
+ * 100% compatible with POSIX with saved IDs.
+ *
+ * SMP: There are not races, the GIDs are checked only by filesystem
+ * operations (as far as semantic preservation is concerned).
+ */
+#ifdef CONFIG_MULTIUSER
+long __sys_setregid(gid_t rgid, gid_t egid)
+{
+ struct user_namespace *ns = current_user_ns();
+ const struct cred *old;
+ struct cred *new;
+ int retval;
+ kgid_t krgid, kegid;
+
+ krgid = make_kgid(ns, rgid);
+ kegid = make_kgid(ns, egid);
+
+ if ((rgid != (gid_t) -1) && !gid_valid(krgid))
+ return -EINVAL;
+ if ((egid != (gid_t) -1) && !gid_valid(kegid))
+ return -EINVAL;
+
+ new = prepare_creds();
+ if (!new)
+ return -ENOMEM;
+ old = current_cred();
+
+ retval = -EPERM;
+ if (rgid != (gid_t) -1) {
+ if (gid_eq(old->gid, krgid) ||
+ gid_eq(old->egid, krgid) ||
+ ns_capable(old->user_ns, CAP_SETGID))
+ new->gid = krgid;
+ else
+ goto error;
+ }
+ if (egid != (gid_t) -1) {
+ if (gid_eq(old->gid, kegid) ||
+ gid_eq(old->egid, kegid) ||
+ gid_eq(old->sgid, kegid) ||
+ ns_capable(old->user_ns, CAP_SETGID))
+ new->egid = kegid;
+ else
+ goto error;
+ }
+
+ if (rgid != (gid_t) -1 ||
+ (egid != (gid_t) -1 && !gid_eq(kegid, old->gid)))
+ new->sgid = new->egid;
+ new->fsgid = new->egid;
+
+ return commit_creds(new);
+
+error:
+ abort_creds(new);
+ return retval;
+}
+
+SYSCALL_DEFINE2(setregid, gid_t, rgid, gid_t, egid)
+{
+ return __sys_setregid(rgid, egid);
+}
+
+/*
+ * setgid() is implemented like SysV w/ SAVED_IDS
+ *
+ * SMP: Same implicit races as above.
+ */
+long __sys_setgid(gid_t gid)
+{
+ struct user_namespace *ns = current_user_ns();
+ const struct cred *old;
+ struct cred *new;
+ int retval;
+ kgid_t kgid;
+
+ kgid = make_kgid(ns, gid);
+ if (!gid_valid(kgid))
+ return -EINVAL;
+
+ new = prepare_creds();
+ if (!new)
+ return -ENOMEM;
+ old = current_cred();
+
+ retval = -EPERM;
+ if (ns_capable(old->user_ns, CAP_SETGID))
+ new->gid = new->egid = new->sgid = new->fsgid = kgid;
+ else if (gid_eq(kgid, old->gid) || gid_eq(kgid, old->sgid))
+ new->egid = new->fsgid = kgid;
+ else
+ goto error;
+
+ return commit_creds(new);
+
+error:
+ abort_creds(new);
+ return retval;
+}
+
+SYSCALL_DEFINE1(setgid, gid_t, gid)
+{
+ return __sys_setgid(gid);
+}
+
+/*
+ * change the user struct in a credentials set to match the new UID
+ */
+static int set_user(struct cred *new)
+{
+ struct user_struct *new_user;
+
+ new_user = alloc_uid(new->uid);
+ if (!new_user)
+ return -EAGAIN;
+
+ /*
+ * We don't fail in case of NPROC limit excess here because too many
+ * poorly written programs don't check set*uid() return code, assuming
+ * it never fails if called by root. We may still enforce NPROC limit
+ * for programs doing set*uid()+execve() by harmlessly deferring the
+ * failure to the execve() stage.
+ */
+ if (atomic_read(&new_user->processes) >= rlimit(RLIMIT_NPROC) &&
+ new_user != INIT_USER)
+ current->flags |= PF_NPROC_EXCEEDED;
+ else
+ current->flags &= ~PF_NPROC_EXCEEDED;
+
+ free_uid(new->user);
+ new->user = new_user;
+ return 0;
+}
+
+/*
+ * Unprivileged users may change the real uid to the effective uid
+ * or vice versa. (BSD-style)
+ *
+ * If you set the real uid at all, or set the effective uid to a value not
+ * equal to the real uid, then the saved uid is set to the new effective uid.
+ *
+ * This makes it possible for a setuid program to completely drop its
+ * privileges, which is often a useful assertion to make when you are doing
+ * a security audit over a program.
+ *
+ * The general idea is that a program which uses just setreuid() will be
+ * 100% compatible with BSD. A program which uses just setuid() will be
+ * 100% compatible with POSIX with saved IDs.
+ */
+long __sys_setreuid(uid_t ruid, uid_t euid)
+{
+ struct user_namespace *ns = current_user_ns();
+ const struct cred *old;
+ struct cred *new;
+ int retval;
+ kuid_t kruid, keuid;
+
+ kruid = make_kuid(ns, ruid);
+ keuid = make_kuid(ns, euid);
+
+ if ((ruid != (uid_t) -1) && !uid_valid(kruid))
+ return -EINVAL;
+ if ((euid != (uid_t) -1) && !uid_valid(keuid))
+ return -EINVAL;
+
+ new = prepare_creds();
+ if (!new)
+ return -ENOMEM;
+ old = current_cred();
+
+ retval = -EPERM;
+ if (ruid != (uid_t) -1) {
+ new->uid = kruid;
+ if (!uid_eq(old->uid, kruid) &&
+ !uid_eq(old->euid, kruid) &&
+ !ns_capable(old->user_ns, CAP_SETUID))
+ goto error;
+ }
+
+ if (euid != (uid_t) -1) {
+ new->euid = keuid;
+ if (!uid_eq(old->uid, keuid) &&
+ !uid_eq(old->euid, keuid) &&
+ !uid_eq(old->suid, keuid) &&
+ !ns_capable(old->user_ns, CAP_SETUID))
+ goto error;
+ }
+
+ if (!uid_eq(new->uid, old->uid)) {
+ retval = set_user(new);
+ if (retval < 0)
+ goto error;
+ }
+ if (ruid != (uid_t) -1 ||
+ (euid != (uid_t) -1 && !uid_eq(keuid, old->uid)))
+ new->suid = new->euid;
+ new->fsuid = new->euid;
+
+ retval = security_task_fix_setuid(new, old, LSM_SETID_RE);
+ if (retval < 0)
+ goto error;
+
+ return commit_creds(new);
+
+error:
+ abort_creds(new);
+ return retval;
+}
+
+SYSCALL_DEFINE2(setreuid, uid_t, ruid, uid_t, euid)
+{
+ return __sys_setreuid(ruid, euid);
+}
+
+/*
+ * setuid() is implemented like SysV with SAVED_IDS
+ *
+ * Note that SAVED_ID's is deficient in that a setuid root program
+ * like sendmail, for example, cannot set its uid to be a normal
+ * user and then switch back, because if you're root, setuid() sets
+ * the saved uid too. If you don't like this, blame the bright people
+ * in the POSIX committee and/or USG. Note that the BSD-style setreuid()
+ * will allow a root program to temporarily drop privileges and be able to
+ * regain them by swapping the real and effective uid.
+ */
+long __sys_setuid(uid_t uid)
+{
+ struct user_namespace *ns = current_user_ns();
+ const struct cred *old;
+ struct cred *new;
+ int retval;
+ kuid_t kuid;
+
+ kuid = make_kuid(ns, uid);
+ if (!uid_valid(kuid))
+ return -EINVAL;
+
+ new = prepare_creds();
+ if (!new)
+ return -ENOMEM;
+ old = current_cred();
+
+ retval = -EPERM;
+ if (ns_capable(old->user_ns, CAP_SETUID)) {
+ new->suid = new->uid = kuid;
+ if (!uid_eq(kuid, old->uid)) {
+ retval = set_user(new);
+ if (retval < 0)
+ goto error;
+ }
+ } else if (!uid_eq(kuid, old->uid) && !uid_eq(kuid, new->suid)) {
+ goto error;
+ }
+
+ new->fsuid = new->euid = kuid;
+
+ retval = security_task_fix_setuid(new, old, LSM_SETID_ID);
+ if (retval < 0)
+ goto error;
+
+ return commit_creds(new);
+
+error:
+ abort_creds(new);
+ return retval;
+}
+
+SYSCALL_DEFINE1(setuid, uid_t, uid)
+{
+ return __sys_setuid(uid);
+}
+
+
+/*
+ * This function implements a generic ability to update ruid, euid,
+ * and suid. This allows you to implement the 4.4 compatible seteuid().
+ */
+long __sys_setresuid(uid_t ruid, uid_t euid, uid_t suid)
+{
+ struct user_namespace *ns = current_user_ns();
+ const struct cred *old;
+ struct cred *new;
+ int retval;
+ kuid_t kruid, keuid, ksuid;
+
+ kruid = make_kuid(ns, ruid);
+ keuid = make_kuid(ns, euid);
+ ksuid = make_kuid(ns, suid);
+
+ if ((ruid != (uid_t) -1) && !uid_valid(kruid))
+ return -EINVAL;
+
+ if ((euid != (uid_t) -1) && !uid_valid(keuid))
+ return -EINVAL;
+
+ if ((suid != (uid_t) -1) && !uid_valid(ksuid))
+ return -EINVAL;
+
+ new = prepare_creds();
+ if (!new)
+ return -ENOMEM;
+
+ old = current_cred();
+
+ retval = -EPERM;
+ if (!ns_capable(old->user_ns, CAP_SETUID)) {
+ if (ruid != (uid_t) -1 && !uid_eq(kruid, old->uid) &&
+ !uid_eq(kruid, old->euid) && !uid_eq(kruid, old->suid))
+ goto error;
+ if (euid != (uid_t) -1 && !uid_eq(keuid, old->uid) &&
+ !uid_eq(keuid, old->euid) && !uid_eq(keuid, old->suid))
+ goto error;
+ if (suid != (uid_t) -1 && !uid_eq(ksuid, old->uid) &&
+ !uid_eq(ksuid, old->euid) && !uid_eq(ksuid, old->suid))
+ goto error;
+ }
+
+ if (ruid != (uid_t) -1) {
+ new->uid = kruid;
+ if (!uid_eq(kruid, old->uid)) {
+ retval = set_user(new);
+ if (retval < 0)
+ goto error;
+ }
+ }
+ if (euid != (uid_t) -1)
+ new->euid = keuid;
+ if (suid != (uid_t) -1)
+ new->suid = ksuid;
+ new->fsuid = new->euid;
+
+ retval = security_task_fix_setuid(new, old, LSM_SETID_RES);
+ if (retval < 0)
+ goto error;
+
+ return commit_creds(new);
+
+error:
+ abort_creds(new);
+ return retval;
+}
+
+SYSCALL_DEFINE3(setresuid, uid_t, ruid, uid_t, euid, uid_t, suid)
+{
+ return __sys_setresuid(ruid, euid, suid);
+}
+
+SYSCALL_DEFINE3(getresuid, uid_t __user *, ruidp, uid_t __user *, euidp, uid_t __user *, suidp)
+{
+ const struct cred *cred = current_cred();
+ int retval;
+ uid_t ruid, euid, suid;
+
+ ruid = from_kuid_munged(cred->user_ns, cred->uid);
+ euid = from_kuid_munged(cred->user_ns, cred->euid);
+ suid = from_kuid_munged(cred->user_ns, cred->suid);
+
+ retval = put_user(ruid, ruidp);
+ if (!retval) {
+ retval = put_user(euid, euidp);
+ if (!retval)
+ return put_user(suid, suidp);
+ }
+ return retval;
+}
+
+/*
+ * Same as above, but for rgid, egid, sgid.
+ */
+long __sys_setresgid(gid_t rgid, gid_t egid, gid_t sgid)
+{
+ struct user_namespace *ns = current_user_ns();
+ const struct cred *old;
+ struct cred *new;
+ int retval;
+ kgid_t krgid, kegid, ksgid;
+
+ krgid = make_kgid(ns, rgid);
+ kegid = make_kgid(ns, egid);
+ ksgid = make_kgid(ns, sgid);
+
+ if ((rgid != (gid_t) -1) && !gid_valid(krgid))
+ return -EINVAL;
+ if ((egid != (gid_t) -1) && !gid_valid(kegid))
+ return -EINVAL;
+ if ((sgid != (gid_t) -1) && !gid_valid(ksgid))
+ return -EINVAL;
+
+ new = prepare_creds();
+ if (!new)
+ return -ENOMEM;
+ old = current_cred();
+
+ retval = -EPERM;
+ if (!ns_capable(old->user_ns, CAP_SETGID)) {
+ if (rgid != (gid_t) -1 && !gid_eq(krgid, old->gid) &&
+ !gid_eq(krgid, old->egid) && !gid_eq(krgid, old->sgid))
+ goto error;
+ if (egid != (gid_t) -1 && !gid_eq(kegid, old->gid) &&
+ !gid_eq(kegid, old->egid) && !gid_eq(kegid, old->sgid))
+ goto error;
+ if (sgid != (gid_t) -1 && !gid_eq(ksgid, old->gid) &&
+ !gid_eq(ksgid, old->egid) && !gid_eq(ksgid, old->sgid))
+ goto error;
+ }
+
+ if (rgid != (gid_t) -1)
+ new->gid = krgid;
+ if (egid != (gid_t) -1)
+ new->egid = kegid;
+ if (sgid != (gid_t) -1)
+ new->sgid = ksgid;
+ new->fsgid = new->egid;
+
+ return commit_creds(new);
+
+error:
+ abort_creds(new);
+ return retval;
+}
+
+SYSCALL_DEFINE3(setresgid, gid_t, rgid, gid_t, egid, gid_t, sgid)
+{
+ return __sys_setresgid(rgid, egid, sgid);
+}
+
+SYSCALL_DEFINE3(getresgid, gid_t __user *, rgidp, gid_t __user *, egidp, gid_t __user *, sgidp)
+{
+ const struct cred *cred = current_cred();
+ int retval;
+ gid_t rgid, egid, sgid;
+
+ rgid = from_kgid_munged(cred->user_ns, cred->gid);
+ egid = from_kgid_munged(cred->user_ns, cred->egid);
+ sgid = from_kgid_munged(cred->user_ns, cred->sgid);
+
+ retval = put_user(rgid, rgidp);
+ if (!retval) {
+ retval = put_user(egid, egidp);
+ if (!retval)
+ retval = put_user(sgid, sgidp);
+ }
+
+ return retval;
+}
+
+
+/*
+ * "setfsuid()" sets the fsuid - the uid used for filesystem checks. This
+ * is used for "access()" and for the NFS daemon (letting nfsd stay at
+ * whatever uid it wants to). It normally shadows "euid", except when
+ * explicitly set by setfsuid() or for access..
+ */
+long __sys_setfsuid(uid_t uid)
+{
+ const struct cred *old;
+ struct cred *new;
+ uid_t old_fsuid;
+ kuid_t kuid;
+
+ old = current_cred();
+ old_fsuid = from_kuid_munged(old->user_ns, old->fsuid);
+
+ kuid = make_kuid(old->user_ns, uid);
+ if (!uid_valid(kuid))
+ return old_fsuid;
+
+ new = prepare_creds();
+ if (!new)
+ return old_fsuid;
+
+ if (uid_eq(kuid, old->uid) || uid_eq(kuid, old->euid) ||
+ uid_eq(kuid, old->suid) || uid_eq(kuid, old->fsuid) ||
+ ns_capable(old->user_ns, CAP_SETUID)) {
+ if (!uid_eq(kuid, old->fsuid)) {
+ new->fsuid = kuid;
+ if (security_task_fix_setuid(new, old, LSM_SETID_FS) == 0)
+ goto change_okay;
+ }
+ }
+
+ abort_creds(new);
+ return old_fsuid;
+
+change_okay:
+ commit_creds(new);
+ return old_fsuid;
+}
+
+SYSCALL_DEFINE1(setfsuid, uid_t, uid)
+{
+ return __sys_setfsuid(uid);
+}
+
+/*
+ * Samma på svenska..
+ */
+long __sys_setfsgid(gid_t gid)
+{
+ const struct cred *old;
+ struct cred *new;
+ gid_t old_fsgid;
+ kgid_t kgid;
+
+ old = current_cred();
+ old_fsgid = from_kgid_munged(old->user_ns, old->fsgid);
+
+ kgid = make_kgid(old->user_ns, gid);
+ if (!gid_valid(kgid))
+ return old_fsgid;
+
+ new = prepare_creds();
+ if (!new)
+ return old_fsgid;
+
+ if (gid_eq(kgid, old->gid) || gid_eq(kgid, old->egid) ||
+ gid_eq(kgid, old->sgid) || gid_eq(kgid, old->fsgid) ||
+ ns_capable(old->user_ns, CAP_SETGID)) {
+ if (!gid_eq(kgid, old->fsgid)) {
+ new->fsgid = kgid;
+ goto change_okay;
+ }
+ }
+
+ abort_creds(new);
+ return old_fsgid;
+
+change_okay:
+ commit_creds(new);
+ return old_fsgid;
+}
+
+SYSCALL_DEFINE1(setfsgid, gid_t, gid)
+{
+ return __sys_setfsgid(gid);
+}
+#endif /* CONFIG_MULTIUSER */
+
+/**
+ * sys_getpid - return the thread group id of the current process
+ *
+ * Note, despite the name, this returns the tgid not the pid. The tgid and
+ * the pid are identical unless CLONE_THREAD was specified on clone() in
+ * which case the tgid is the same in all threads of the same group.
+ *
+ * This is SMP safe as current->tgid does not change.
+ */
+SYSCALL_DEFINE0(getpid)
+{
+ return task_tgid_vnr(current);
+}
+
+/* Thread ID - the internal kernel "pid" */
+SYSCALL_DEFINE0(gettid)
+{
+ return task_pid_vnr(current);
+}
+
+/*
+ * Accessing ->real_parent is not SMP-safe, it could
+ * change from under us. However, we can use a stale
+ * value of ->real_parent under rcu_read_lock(), see
+ * release_task()->call_rcu(delayed_put_task_struct).
+ */
+SYSCALL_DEFINE0(getppid)
+{
+ int pid;
+
+ rcu_read_lock();
+ pid = task_tgid_vnr(rcu_dereference(current->real_parent));
+ rcu_read_unlock();
+
+ return pid;
+}
+
+SYSCALL_DEFINE0(getuid)
+{
+ /* Only we change this so SMP safe */
+ return from_kuid_munged(current_user_ns(), current_uid());
+}
+
+SYSCALL_DEFINE0(geteuid)
+{
+ /* Only we change this so SMP safe */
+ return from_kuid_munged(current_user_ns(), current_euid());
+}
+
+SYSCALL_DEFINE0(getgid)
+{
+ /* Only we change this so SMP safe */
+ return from_kgid_munged(current_user_ns(), current_gid());
+}
+
+SYSCALL_DEFINE0(getegid)
+{
+ /* Only we change this so SMP safe */
+ return from_kgid_munged(current_user_ns(), current_egid());
+}
+
+static void do_sys_times(struct tms *tms)
+{
+ u64 tgutime, tgstime, cutime, cstime;
+
+ thread_group_cputime_adjusted(current, &tgutime, &tgstime);
+ cutime = current->signal->cutime;
+ cstime = current->signal->cstime;
+ tms->tms_utime = nsec_to_clock_t(tgutime);
+ tms->tms_stime = nsec_to_clock_t(tgstime);
+ tms->tms_cutime = nsec_to_clock_t(cutime);
+ tms->tms_cstime = nsec_to_clock_t(cstime);
+}
+
+SYSCALL_DEFINE1(times, struct tms __user *, tbuf)
+{
+ if (tbuf) {
+ struct tms tmp;
+
+ do_sys_times(&tmp);
+ if (copy_to_user(tbuf, &tmp, sizeof(struct tms)))
+ return -EFAULT;
+ }
+ force_successful_syscall_return();
+ return (long) jiffies_64_to_clock_t(get_jiffies_64());
+}
+
+#ifdef CONFIG_COMPAT
+static compat_clock_t clock_t_to_compat_clock_t(clock_t x)
+{
+ return compat_jiffies_to_clock_t(clock_t_to_jiffies(x));
+}
+
+COMPAT_SYSCALL_DEFINE1(times, struct compat_tms __user *, tbuf)
+{
+ if (tbuf) {
+ struct tms tms;
+ struct compat_tms tmp;
+
+ do_sys_times(&tms);
+ /* Convert our struct tms to the compat version. */
+ tmp.tms_utime = clock_t_to_compat_clock_t(tms.tms_utime);
+ tmp.tms_stime = clock_t_to_compat_clock_t(tms.tms_stime);
+ tmp.tms_cutime = clock_t_to_compat_clock_t(tms.tms_cutime);
+ tmp.tms_cstime = clock_t_to_compat_clock_t(tms.tms_cstime);
+ if (copy_to_user(tbuf, &tmp, sizeof(tmp)))
+ return -EFAULT;
+ }
+ force_successful_syscall_return();
+ return compat_jiffies_to_clock_t(jiffies);
+}
+#endif
+
+/*
+ * This needs some heavy checking ...
+ * I just haven't the stomach for it. I also don't fully
+ * understand sessions/pgrp etc. Let somebody who does explain it.
+ *
+ * OK, I think I have the protection semantics right.... this is really
+ * only important on a multi-user system anyway, to make sure one user
+ * can't send a signal to a process owned by another. -TYT, 12/12/91
+ *
+ * !PF_FORKNOEXEC check to conform completely to POSIX.
+ */
+SYSCALL_DEFINE2(setpgid, pid_t, pid, pid_t, pgid)
+{
+ struct task_struct *p;
+ struct task_struct *group_leader = current->group_leader;
+ struct pid *pgrp;
+ int err;
+
+ if (!pid)
+ pid = task_pid_vnr(group_leader);
+ if (!pgid)
+ pgid = pid;
+ if (pgid < 0)
+ return -EINVAL;
+ rcu_read_lock();
+
+ /* From this point forward we keep holding onto the tasklist lock
+ * so that our parent does not change from under us. -DaveM
+ */
+ write_lock_irq(&tasklist_lock);
+
+ err = -ESRCH;
+ p = find_task_by_vpid(pid);
+ if (!p)
+ goto out;
+
+ err = -EINVAL;
+ if (!thread_group_leader(p))
+ goto out;
+
+ if (same_thread_group(p->real_parent, group_leader)) {
+ err = -EPERM;
+ if (task_session(p) != task_session(group_leader))
+ goto out;
+ err = -EACCES;
+ if (!(p->flags & PF_FORKNOEXEC))
+ goto out;
+ } else {
+ err = -ESRCH;
+ if (p != group_leader)
+ goto out;
+ }
+
+ err = -EPERM;
+ if (p->signal->leader)
+ goto out;
+
+ pgrp = task_pid(p);
+ if (pgid != pid) {
+ struct task_struct *g;
+
+ pgrp = find_vpid(pgid);
+ g = pid_task(pgrp, PIDTYPE_PGID);
+ if (!g || task_session(g) != task_session(group_leader))
+ goto out;
+ }
+
+ err = security_task_setpgid(p, pgid);
+ if (err)
+ goto out;
+
+ if (task_pgrp(p) != pgrp)
+ change_pid(p, PIDTYPE_PGID, pgrp);
+
+ err = 0;
+out:
+ /* All paths lead to here, thus we are safe. -DaveM */
+ write_unlock_irq(&tasklist_lock);
+ rcu_read_unlock();
+ return err;
+}
+
+static int do_getpgid(pid_t pid)
+{
+ struct task_struct *p;
+ struct pid *grp;
+ int retval;
+
+ rcu_read_lock();
+ if (!pid)
+ grp = task_pgrp(current);
+ else {
+ retval = -ESRCH;
+ p = find_task_by_vpid(pid);
+ if (!p)
+ goto out;
+ grp = task_pgrp(p);
+ if (!grp)
+ goto out;
+
+ retval = security_task_getpgid(p);
+ if (retval)
+ goto out;
+ }
+ retval = pid_vnr(grp);
+out:
+ rcu_read_unlock();
+ return retval;
+}
+
+SYSCALL_DEFINE1(getpgid, pid_t, pid)
+{
+ return do_getpgid(pid);
+}
+
+#ifdef __ARCH_WANT_SYS_GETPGRP
+
+SYSCALL_DEFINE0(getpgrp)
+{
+ return do_getpgid(0);
+}
+
+#endif
+
+SYSCALL_DEFINE1(getsid, pid_t, pid)
+{
+ struct task_struct *p;
+ struct pid *sid;
+ int retval;
+
+ rcu_read_lock();
+ if (!pid)
+ sid = task_session(current);
+ else {
+ retval = -ESRCH;
+ p = find_task_by_vpid(pid);
+ if (!p)
+ goto out;
+ sid = task_session(p);
+ if (!sid)
+ goto out;
+
+ retval = security_task_getsid(p);
+ if (retval)
+ goto out;
+ }
+ retval = pid_vnr(sid);
+out:
+ rcu_read_unlock();
+ return retval;
+}
+
+static void set_special_pids(struct pid *pid)
+{
+ struct task_struct *curr = current->group_leader;
+
+ if (task_session(curr) != pid)
+ change_pid(curr, PIDTYPE_SID, pid);
+
+ if (task_pgrp(curr) != pid)
+ change_pid(curr, PIDTYPE_PGID, pid);
+}
+
+int ksys_setsid(void)
+{
+ struct task_struct *group_leader = current->group_leader;
+ struct pid *sid = task_pid(group_leader);
+ pid_t session = pid_vnr(sid);
+ int err = -EPERM;
+
+ write_lock_irq(&tasklist_lock);
+ /* Fail if I am already a session leader */
+ if (group_leader->signal->leader)
+ goto out;
+
+ /* Fail if a process group id already exists that equals the
+ * proposed session id.
+ */
+ if (pid_task(sid, PIDTYPE_PGID))
+ goto out;
+
+ group_leader->signal->leader = 1;
+ set_special_pids(sid);
+
+ proc_clear_tty(group_leader);
+
+ err = session;
+out:
+ write_unlock_irq(&tasklist_lock);
+ if (err > 0) {
+ proc_sid_connector(group_leader);
+ sched_autogroup_create_attach(group_leader);
+ }
+ return err;
+}
+
+SYSCALL_DEFINE0(setsid)
+{
+ return ksys_setsid();
+}
+
+DECLARE_RWSEM(uts_sem);
+
+#ifdef COMPAT_UTS_MACHINE
+#define override_architecture(name) \
+ (personality(current->personality) == PER_LINUX32 && \
+ copy_to_user(name->machine, COMPAT_UTS_MACHINE, \
+ sizeof(COMPAT_UTS_MACHINE)))
+#else
+#define override_architecture(name) 0
+#endif
+
+/*
+ * Work around broken programs that cannot handle "Linux 3.0".
+ * Instead we map 3.x to 2.6.40+x, so e.g. 3.0 would be 2.6.40
+ * And we map 4.x to 2.6.60+x, so 4.0 would be 2.6.60.
+ */
+static int override_release(char __user *release, size_t len)
+{
+ int ret = 0;
+
+ if (current->personality & UNAME26) {
+ const char *rest = UTS_RELEASE;
+ char buf[65] = { 0 };
+ int ndots = 0;
+ unsigned v;
+ size_t copy;
+
+ while (*rest) {
+ if (*rest == '.' && ++ndots >= 3)
+ break;
+ if (!isdigit(*rest) && *rest != '.')
+ break;
+ rest++;
+ }
+ v = ((LINUX_VERSION_CODE >> 8) & 0xff) + 60;
+ copy = clamp_t(size_t, len, 1, sizeof(buf));
+ copy = scnprintf(buf, copy, "2.6.%u%s", v, rest);
+ ret = copy_to_user(release, buf, copy + 1);
+ }
+ return ret;
+}
+
+SYSCALL_DEFINE1(newuname, struct new_utsname __user *, name)
+{
+ struct new_utsname tmp;
+
+ down_read(&uts_sem);
+ memcpy(&tmp, utsname(), sizeof(tmp));
+ up_read(&uts_sem);
+ if (copy_to_user(name, &tmp, sizeof(tmp)))
+ return -EFAULT;
+
+ if (override_release(name->release, sizeof(name->release)))
+ return -EFAULT;
+ if (override_architecture(name))
+ return -EFAULT;
+ return 0;
+}
+
+#ifdef __ARCH_WANT_SYS_OLD_UNAME
+/*
+ * Old cruft
+ */
+SYSCALL_DEFINE1(uname, struct old_utsname __user *, name)
+{
+ struct old_utsname tmp;
+
+ if (!name)
+ return -EFAULT;
+
+ down_read(&uts_sem);
+ memcpy(&tmp, utsname(), sizeof(tmp));
+ up_read(&uts_sem);
+ if (copy_to_user(name, &tmp, sizeof(tmp)))
+ return -EFAULT;
+
+ if (override_release(name->release, sizeof(name->release)))
+ return -EFAULT;
+ if (override_architecture(name))
+ return -EFAULT;
+ return 0;
+}
+
+SYSCALL_DEFINE1(olduname, struct oldold_utsname __user *, name)
+{
+ struct oldold_utsname tmp = {};
+
+ if (!name)
+ return -EFAULT;
+
+ down_read(&uts_sem);
+ memcpy(&tmp.sysname, &utsname()->sysname, __OLD_UTS_LEN);
+ memcpy(&tmp.nodename, &utsname()->nodename, __OLD_UTS_LEN);
+ memcpy(&tmp.release, &utsname()->release, __OLD_UTS_LEN);
+ memcpy(&tmp.version, &utsname()->version, __OLD_UTS_LEN);
+ memcpy(&tmp.machine, &utsname()->machine, __OLD_UTS_LEN);
+ up_read(&uts_sem);
+ if (copy_to_user(name, &tmp, sizeof(tmp)))
+ return -EFAULT;
+
+ if (override_architecture(name))
+ return -EFAULT;
+ if (override_release(name->release, sizeof(name->release)))
+ return -EFAULT;
+ return 0;
+}
+#endif
+
+SYSCALL_DEFINE2(sethostname, char __user *, name, int, len)
+{
+ int errno;
+ char tmp[__NEW_UTS_LEN];
+
+ if (!ns_capable(current->nsproxy->uts_ns->user_ns, CAP_SYS_ADMIN))
+ return -EPERM;
+
+ if (len < 0 || len > __NEW_UTS_LEN)
+ return -EINVAL;
+ errno = -EFAULT;
+ if (!copy_from_user(tmp, name, len)) {
+ struct new_utsname *u;
+
+ down_write(&uts_sem);
+ u = utsname();
+ memcpy(u->nodename, tmp, len);
+ memset(u->nodename + len, 0, sizeof(u->nodename) - len);
+ errno = 0;
+ uts_proc_notify(UTS_PROC_HOSTNAME);
+ up_write(&uts_sem);
+ }
+ return errno;
+}
+
+#ifdef __ARCH_WANT_SYS_GETHOSTNAME
+
+SYSCALL_DEFINE2(gethostname, char __user *, name, int, len)
+{
+ int i;
+ struct new_utsname *u;
+ char tmp[__NEW_UTS_LEN + 1];
+
+ if (len < 0)
+ return -EINVAL;
+ down_read(&uts_sem);
+ u = utsname();
+ i = 1 + strlen(u->nodename);
+ if (i > len)
+ i = len;
+ memcpy(tmp, u->nodename, i);
+ up_read(&uts_sem);
+ if (copy_to_user(name, tmp, i))
+ return -EFAULT;
+ return 0;
+}
+
+#endif
+
+/*
+ * Only setdomainname; getdomainname can be implemented by calling
+ * uname()
+ */
+SYSCALL_DEFINE2(setdomainname, char __user *, name, int, len)
+{
+ int errno;
+ char tmp[__NEW_UTS_LEN];
+
+ if (!ns_capable(current->nsproxy->uts_ns->user_ns, CAP_SYS_ADMIN))
+ return -EPERM;
+ if (len < 0 || len > __NEW_UTS_LEN)
+ return -EINVAL;
+
+ errno = -EFAULT;
+ if (!copy_from_user(tmp, name, len)) {
+ struct new_utsname *u;
+
+ down_write(&uts_sem);
+ u = utsname();
+ memcpy(u->domainname, tmp, len);
+ memset(u->domainname + len, 0, sizeof(u->domainname) - len);
+ errno = 0;
+ uts_proc_notify(UTS_PROC_DOMAINNAME);
+ up_write(&uts_sem);
+ }
+ return errno;
+}
+
+SYSCALL_DEFINE2(getrlimit, unsigned int, resource, struct rlimit __user *, rlim)
+{
+ struct rlimit value;
+ int ret;
+
+ ret = do_prlimit(current, resource, NULL, &value);
+ if (!ret)
+ ret = copy_to_user(rlim, &value, sizeof(*rlim)) ? -EFAULT : 0;
+
+ return ret;
+}
+
+#ifdef CONFIG_COMPAT
+
+COMPAT_SYSCALL_DEFINE2(setrlimit, unsigned int, resource,
+ struct compat_rlimit __user *, rlim)
+{
+ struct rlimit r;
+ struct compat_rlimit r32;
+
+ if (copy_from_user(&r32, rlim, sizeof(struct compat_rlimit)))
+ return -EFAULT;
+
+ if (r32.rlim_cur == COMPAT_RLIM_INFINITY)
+ r.rlim_cur = RLIM_INFINITY;
+ else
+ r.rlim_cur = r32.rlim_cur;
+ if (r32.rlim_max == COMPAT_RLIM_INFINITY)
+ r.rlim_max = RLIM_INFINITY;
+ else
+ r.rlim_max = r32.rlim_max;
+ return do_prlimit(current, resource, &r, NULL);
+}
+
+COMPAT_SYSCALL_DEFINE2(getrlimit, unsigned int, resource,
+ struct compat_rlimit __user *, rlim)
+{
+ struct rlimit r;
+ int ret;
+
+ ret = do_prlimit(current, resource, NULL, &r);
+ if (!ret) {
+ struct compat_rlimit r32;
+ if (r.rlim_cur > COMPAT_RLIM_INFINITY)
+ r32.rlim_cur = COMPAT_RLIM_INFINITY;
+ else
+ r32.rlim_cur = r.rlim_cur;
+ if (r.rlim_max > COMPAT_RLIM_INFINITY)
+ r32.rlim_max = COMPAT_RLIM_INFINITY;
+ else
+ r32.rlim_max = r.rlim_max;
+
+ if (copy_to_user(rlim, &r32, sizeof(struct compat_rlimit)))
+ return -EFAULT;
+ }
+ return ret;
+}
+
+#endif
+
+#ifdef __ARCH_WANT_SYS_OLD_GETRLIMIT
+
+/*
+ * Back compatibility for getrlimit. Needed for some apps.
+ */
+SYSCALL_DEFINE2(old_getrlimit, unsigned int, resource,
+ struct rlimit __user *, rlim)
+{
+ struct rlimit x;
+ if (resource >= RLIM_NLIMITS)
+ return -EINVAL;
+
+ resource = array_index_nospec(resource, RLIM_NLIMITS);
+ task_lock(current->group_leader);
+ x = current->signal->rlim[resource];
+ task_unlock(current->group_leader);
+ if (x.rlim_cur > 0x7FFFFFFF)
+ x.rlim_cur = 0x7FFFFFFF;
+ if (x.rlim_max > 0x7FFFFFFF)
+ x.rlim_max = 0x7FFFFFFF;
+ return copy_to_user(rlim, &x, sizeof(x)) ? -EFAULT : 0;
+}
+
+#ifdef CONFIG_COMPAT
+COMPAT_SYSCALL_DEFINE2(old_getrlimit, unsigned int, resource,
+ struct compat_rlimit __user *, rlim)
+{
+ struct rlimit r;
+
+ if (resource >= RLIM_NLIMITS)
+ return -EINVAL;
+
+ resource = array_index_nospec(resource, RLIM_NLIMITS);
+ task_lock(current->group_leader);
+ r = current->signal->rlim[resource];
+ task_unlock(current->group_leader);
+ if (r.rlim_cur > 0x7FFFFFFF)
+ r.rlim_cur = 0x7FFFFFFF;
+ if (r.rlim_max > 0x7FFFFFFF)
+ r.rlim_max = 0x7FFFFFFF;
+
+ if (put_user(r.rlim_cur, &rlim->rlim_cur) ||
+ put_user(r.rlim_max, &rlim->rlim_max))
+ return -EFAULT;
+ return 0;
+}
+#endif
+
+#endif
+
+static inline bool rlim64_is_infinity(__u64 rlim64)
+{
+#if BITS_PER_LONG < 64
+ return rlim64 >= ULONG_MAX;
+#else
+ return rlim64 == RLIM64_INFINITY;
+#endif
+}
+
+static void rlim_to_rlim64(const struct rlimit *rlim, struct rlimit64 *rlim64)
+{
+ if (rlim->rlim_cur == RLIM_INFINITY)
+ rlim64->rlim_cur = RLIM64_INFINITY;
+ else
+ rlim64->rlim_cur = rlim->rlim_cur;
+ if (rlim->rlim_max == RLIM_INFINITY)
+ rlim64->rlim_max = RLIM64_INFINITY;
+ else
+ rlim64->rlim_max = rlim->rlim_max;
+}
+
+static void rlim64_to_rlim(const struct rlimit64 *rlim64, struct rlimit *rlim)
+{
+ if (rlim64_is_infinity(rlim64->rlim_cur))
+ rlim->rlim_cur = RLIM_INFINITY;
+ else
+ rlim->rlim_cur = (unsigned long)rlim64->rlim_cur;
+ if (rlim64_is_infinity(rlim64->rlim_max))
+ rlim->rlim_max = RLIM_INFINITY;
+ else
+ rlim->rlim_max = (unsigned long)rlim64->rlim_max;
+}
+
+/* make sure you are allowed to change @tsk limits before calling this */
+int do_prlimit(struct task_struct *tsk, unsigned int resource,
+ struct rlimit *new_rlim, struct rlimit *old_rlim)
+{
+ struct rlimit *rlim;
+ int retval = 0;
+
+ if (resource >= RLIM_NLIMITS)
+ return -EINVAL;
+ if (new_rlim) {
+ if (new_rlim->rlim_cur > new_rlim->rlim_max)
+ return -EINVAL;
+ if (resource == RLIMIT_NOFILE &&
+ new_rlim->rlim_max > sysctl_nr_open)
+ return -EPERM;
+ }
+
+ /* protect tsk->signal and tsk->sighand from disappearing */
+ read_lock(&tasklist_lock);
+ if (!tsk->sighand) {
+ retval = -ESRCH;
+ goto out;
+ }
+
+ rlim = tsk->signal->rlim + resource;
+ task_lock(tsk->group_leader);
+ if (new_rlim) {
+ /* Keep the capable check against init_user_ns until
+ cgroups can contain all limits */
+ if (new_rlim->rlim_max > rlim->rlim_max &&
+ !capable(CAP_SYS_RESOURCE))
+ retval = -EPERM;
+ if (!retval)
+ retval = security_task_setrlimit(tsk, resource, new_rlim);
+ if (resource == RLIMIT_CPU && new_rlim->rlim_cur == 0) {
+ /*
+ * The caller is asking for an immediate RLIMIT_CPU
+ * expiry. But we use the zero value to mean "it was
+ * never set". So let's cheat and make it one second
+ * instead
+ */
+ new_rlim->rlim_cur = 1;
+ }
+ }
+ if (!retval) {
+ if (old_rlim)
+ *old_rlim = *rlim;
+ if (new_rlim)
+ *rlim = *new_rlim;
+ }
+ task_unlock(tsk->group_leader);
+
+ /*
+ * RLIMIT_CPU handling. Note that the kernel fails to return an error
+ * code if it rejected the user's attempt to set RLIMIT_CPU. This is a
+ * very long-standing error, and fixing it now risks breakage of
+ * applications, so we live with it
+ */
+ if (!retval && new_rlim && resource == RLIMIT_CPU &&
+ new_rlim->rlim_cur != RLIM_INFINITY &&
+ IS_ENABLED(CONFIG_POSIX_TIMERS))
+ update_rlimit_cpu(tsk, new_rlim->rlim_cur);
+out:
+ read_unlock(&tasklist_lock);
+ return retval;
+}
+
+/* rcu lock must be held */
+static int check_prlimit_permission(struct task_struct *task,
+ unsigned int flags)
+{
+ const struct cred *cred = current_cred(), *tcred;
+ bool id_match;
+
+ if (current == task)
+ return 0;
+
+ tcred = __task_cred(task);
+ id_match = (uid_eq(cred->uid, tcred->euid) &&
+ uid_eq(cred->uid, tcred->suid) &&
+ uid_eq(cred->uid, tcred->uid) &&
+ gid_eq(cred->gid, tcred->egid) &&
+ gid_eq(cred->gid, tcred->sgid) &&
+ gid_eq(cred->gid, tcred->gid));
+ if (!id_match && !ns_capable(tcred->user_ns, CAP_SYS_RESOURCE))
+ return -EPERM;
+
+ return security_task_prlimit(cred, tcred, flags);
+}
+
+SYSCALL_DEFINE4(prlimit64, pid_t, pid, unsigned int, resource,
+ const struct rlimit64 __user *, new_rlim,
+ struct rlimit64 __user *, old_rlim)
+{
+ struct rlimit64 old64, new64;
+ struct rlimit old, new;
+ struct task_struct *tsk;
+ unsigned int checkflags = 0;
+ int ret;
+
+ if (old_rlim)
+ checkflags |= LSM_PRLIMIT_READ;
+
+ if (new_rlim) {
+ if (copy_from_user(&new64, new_rlim, sizeof(new64)))
+ return -EFAULT;
+ rlim64_to_rlim(&new64, &new);
+ checkflags |= LSM_PRLIMIT_WRITE;
+ }
+
+ rcu_read_lock();
+ tsk = pid ? find_task_by_vpid(pid) : current;
+ if (!tsk) {
+ rcu_read_unlock();
+ return -ESRCH;
+ }
+ ret = check_prlimit_permission(tsk, checkflags);
+ if (ret) {
+ rcu_read_unlock();
+ return ret;
+ }
+ get_task_struct(tsk);
+ rcu_read_unlock();
+
+ ret = do_prlimit(tsk, resource, new_rlim ? &new : NULL,
+ old_rlim ? &old : NULL);
+
+ if (!ret && old_rlim) {
+ rlim_to_rlim64(&old, &old64);
+ if (copy_to_user(old_rlim, &old64, sizeof(old64)))
+ ret = -EFAULT;
+ }
+
+ put_task_struct(tsk);
+ return ret;
+}
+
+SYSCALL_DEFINE2(setrlimit, unsigned int, resource, struct rlimit __user *, rlim)
+{
+ struct rlimit new_rlim;
+
+ if (copy_from_user(&new_rlim, rlim, sizeof(*rlim)))
+ return -EFAULT;
+ return do_prlimit(current, resource, &new_rlim, NULL);
+}
+
+/*
+ * It would make sense to put struct rusage in the task_struct,
+ * except that would make the task_struct be *really big*. After
+ * task_struct gets moved into malloc'ed memory, it would
+ * make sense to do this. It will make moving the rest of the information
+ * a lot simpler! (Which we're not doing right now because we're not
+ * measuring them yet).
+ *
+ * When sampling multiple threads for RUSAGE_SELF, under SMP we might have
+ * races with threads incrementing their own counters. But since word
+ * reads are atomic, we either get new values or old values and we don't
+ * care which for the sums. We always take the siglock to protect reading
+ * the c* fields from p->signal from races with exit.c updating those
+ * fields when reaping, so a sample either gets all the additions of a
+ * given child after it's reaped, or none so this sample is before reaping.
+ *
+ * Locking:
+ * We need to take the siglock for CHILDEREN, SELF and BOTH
+ * for the cases current multithreaded, non-current single threaded
+ * non-current multithreaded. Thread traversal is now safe with
+ * the siglock held.
+ * Strictly speaking, we donot need to take the siglock if we are current and
+ * single threaded, as no one else can take our signal_struct away, no one
+ * else can reap the children to update signal->c* counters, and no one else
+ * can race with the signal-> fields. If we do not take any lock, the
+ * signal-> fields could be read out of order while another thread was just
+ * exiting. So we should place a read memory barrier when we avoid the lock.
+ * On the writer side, write memory barrier is implied in __exit_signal
+ * as __exit_signal releases the siglock spinlock after updating the signal->
+ * fields. But we don't do this yet to keep things simple.
+ *
+ */
+
+static void accumulate_thread_rusage(struct task_struct *t, struct rusage *r)
+{
+ r->ru_nvcsw += t->nvcsw;
+ r->ru_nivcsw += t->nivcsw;
+ r->ru_minflt += t->min_flt;
+ r->ru_majflt += t->maj_flt;
+ r->ru_inblock += task_io_get_inblock(t);
+ r->ru_oublock += task_io_get_oublock(t);
+}
+
+void getrusage(struct task_struct *p, int who, struct rusage *r)
+{
+ struct task_struct *t;
+ unsigned long flags;
+ u64 tgutime, tgstime, utime, stime;
+ unsigned long maxrss = 0;
+
+ memset((char *)r, 0, sizeof (*r));
+ utime = stime = 0;
+
+ if (who == RUSAGE_THREAD) {
+ task_cputime_adjusted(current, &utime, &stime);
+ accumulate_thread_rusage(p, r);
+ maxrss = p->signal->maxrss;
+ goto out;
+ }
+
+ if (!lock_task_sighand(p, &flags))
+ return;
+
+ switch (who) {
+ case RUSAGE_BOTH:
+ case RUSAGE_CHILDREN:
+ utime = p->signal->cutime;
+ stime = p->signal->cstime;
+ r->ru_nvcsw = p->signal->cnvcsw;
+ r->ru_nivcsw = p->signal->cnivcsw;
+ r->ru_minflt = p->signal->cmin_flt;
+ r->ru_majflt = p->signal->cmaj_flt;
+ r->ru_inblock = p->signal->cinblock;
+ r->ru_oublock = p->signal->coublock;
+ maxrss = p->signal->cmaxrss;
+
+ if (who == RUSAGE_CHILDREN)
+ break;
+
+ case RUSAGE_SELF:
+ thread_group_cputime_adjusted(p, &tgutime, &tgstime);
+ utime += tgutime;
+ stime += tgstime;
+ r->ru_nvcsw += p->signal->nvcsw;
+ r->ru_nivcsw += p->signal->nivcsw;
+ r->ru_minflt += p->signal->min_flt;
+ r->ru_majflt += p->signal->maj_flt;
+ r->ru_inblock += p->signal->inblock;
+ r->ru_oublock += p->signal->oublock;
+ if (maxrss < p->signal->maxrss)
+ maxrss = p->signal->maxrss;
+ t = p;
+ do {
+ accumulate_thread_rusage(t, r);
+ } while_each_thread(p, t);
+ break;
+
+ default:
+ BUG();
+ }
+ unlock_task_sighand(p, &flags);
+
+out:
+ r->ru_utime = ns_to_timeval(utime);
+ r->ru_stime = ns_to_timeval(stime);
+
+ if (who != RUSAGE_CHILDREN) {
+ struct mm_struct *mm = get_task_mm(p);
+
+ if (mm) {
+ setmax_mm_hiwater_rss(&maxrss, mm);
+ mmput(mm);
+ }
+ }
+ r->ru_maxrss = maxrss * (PAGE_SIZE / 1024); /* convert pages to KBs */
+}
+
+SYSCALL_DEFINE2(getrusage, int, who, struct rusage __user *, ru)
+{
+ struct rusage r;
+
+ if (who != RUSAGE_SELF && who != RUSAGE_CHILDREN &&
+ who != RUSAGE_THREAD)
+ return -EINVAL;
+
+ getrusage(current, who, &r);
+ return copy_to_user(ru, &r, sizeof(r)) ? -EFAULT : 0;
+}
+
+#ifdef CONFIG_COMPAT
+COMPAT_SYSCALL_DEFINE2(getrusage, int, who, struct compat_rusage __user *, ru)
+{
+ struct rusage r;
+
+ if (who != RUSAGE_SELF && who != RUSAGE_CHILDREN &&
+ who != RUSAGE_THREAD)
+ return -EINVAL;
+
+ getrusage(current, who, &r);
+ return put_compat_rusage(&r, ru);
+}
+#endif
+
+SYSCALL_DEFINE1(umask, int, mask)
+{
+ mask = xchg(¤t->fs->umask, mask & S_IRWXUGO);
+ return mask;
+}
+
+static int prctl_set_mm_exe_file(struct mm_struct *mm, unsigned int fd)
+{
+ struct fd exe;
+ struct file *old_exe, *exe_file;
+ struct inode *inode;
+ int err;
+
+ exe = fdget(fd);
+ if (!exe.file)
+ return -EBADF;
+
+ inode = file_inode(exe.file);
+
+ /*
+ * Because the original mm->exe_file points to executable file, make
+ * sure that this one is executable as well, to avoid breaking an
+ * overall picture.
+ */
+ err = -EACCES;
+ if (!S_ISREG(inode->i_mode) || path_noexec(&exe.file->f_path))
+ goto exit;
+
+ err = inode_permission(inode, MAY_EXEC);
+ if (err)
+ goto exit;
+
+ /*
+ * Forbid mm->exe_file change if old file still mapped.
+ */
+ exe_file = get_mm_exe_file(mm);
+ err = -EBUSY;
+ if (exe_file) {
+ struct vm_area_struct *vma;
+
+ down_read(&mm->mmap_sem);
+ for (vma = mm->mmap; vma; vma = vma->vm_next) {
+ if (!vma->vm_file)
+ continue;
+ if (path_equal(&vma->vm_file->f_path,
+ &exe_file->f_path))
+ goto exit_err;
+ }
+
+ up_read(&mm->mmap_sem);
+ fput(exe_file);
+ }
+
+ err = 0;
+ /* set the new file, lockless */
+ get_file(exe.file);
+ old_exe = xchg(&mm->exe_file, exe.file);
+ if (old_exe)
+ fput(old_exe);
+exit:
+ fdput(exe);
+ return err;
+exit_err:
+ up_read(&mm->mmap_sem);
+ fput(exe_file);
+ goto exit;
+}
+
+/*
+ * WARNING: we don't require any capability here so be very careful
+ * in what is allowed for modification from userspace.
+ */
+static int validate_prctl_map(struct prctl_mm_map *prctl_map)
+{
+ unsigned long mmap_max_addr = TASK_SIZE;
+ struct mm_struct *mm = current->mm;
+ int error = -EINVAL, i;
+
+ static const unsigned char offsets[] = {
+ offsetof(struct prctl_mm_map, start_code),
+ offsetof(struct prctl_mm_map, end_code),
+ offsetof(struct prctl_mm_map, start_data),
+ offsetof(struct prctl_mm_map, end_data),
+ offsetof(struct prctl_mm_map, start_brk),
+ offsetof(struct prctl_mm_map, brk),
+ offsetof(struct prctl_mm_map, start_stack),
+ offsetof(struct prctl_mm_map, arg_start),
+ offsetof(struct prctl_mm_map, arg_end),
+ offsetof(struct prctl_mm_map, env_start),
+ offsetof(struct prctl_mm_map, env_end),
+ };
+
+ /*
+ * Make sure the members are not somewhere outside
+ * of allowed address space.
+ */
+ for (i = 0; i < ARRAY_SIZE(offsets); i++) {
+ u64 val = *(u64 *)((char *)prctl_map + offsets[i]);
+
+ if ((unsigned long)val >= mmap_max_addr ||
+ (unsigned long)val < mmap_min_addr)
+ goto out;
+ }
+
+ /*
+ * Make sure the pairs are ordered.
+ */
+#define __prctl_check_order(__m1, __op, __m2) \
+ ((unsigned long)prctl_map->__m1 __op \
+ (unsigned long)prctl_map->__m2) ? 0 : -EINVAL
+ error = __prctl_check_order(start_code, <, end_code);
+ error |= __prctl_check_order(start_data, <, end_data);
+ error |= __prctl_check_order(start_brk, <=, brk);
+ error |= __prctl_check_order(arg_start, <=, arg_end);
+ error |= __prctl_check_order(env_start, <=, env_end);
+ if (error)
+ goto out;
+#undef __prctl_check_order
+
+ error = -EINVAL;
+
+ /*
+ * @brk should be after @end_data in traditional maps.
+ */
+ if (prctl_map->start_brk <= prctl_map->end_data ||
+ prctl_map->brk <= prctl_map->end_data)
+ goto out;
+
+ /*
+ * Neither we should allow to override limits if they set.
+ */
+ if (check_data_rlimit(rlimit(RLIMIT_DATA), prctl_map->brk,
+ prctl_map->start_brk, prctl_map->end_data,
+ prctl_map->start_data))
+ goto out;
+
+ /*
+ * Someone is trying to cheat the auxv vector.
+ */
+ if (prctl_map->auxv_size) {
+ if (!prctl_map->auxv || prctl_map->auxv_size > sizeof(mm->saved_auxv))
+ goto out;
+ }
+
+ /*
+ * Finally, make sure the caller has the rights to
+ * change /proc/pid/exe link: only local sys admin should
+ * be allowed to.
+ */
+ if (prctl_map->exe_fd != (u32)-1) {
+ if (!ns_capable(current_user_ns(), CAP_SYS_ADMIN))
+ goto out;
+ }
+
+ error = 0;
+out:
+ return error;
+}
+
+#ifdef CONFIG_CHECKPOINT_RESTORE
+static int prctl_set_mm_map(int opt, const void __user *addr, unsigned long data_size)
+{
+ struct prctl_mm_map prctl_map = { .exe_fd = (u32)-1, };
+ unsigned long user_auxv[AT_VECTOR_SIZE];
+ struct mm_struct *mm = current->mm;
+ int error;
+
+ BUILD_BUG_ON(sizeof(user_auxv) != sizeof(mm->saved_auxv));
+ BUILD_BUG_ON(sizeof(struct prctl_mm_map) > 256);
+
+ if (opt == PR_SET_MM_MAP_SIZE)
+ return put_user((unsigned int)sizeof(prctl_map),
+ (unsigned int __user *)addr);
+
+ if (data_size != sizeof(prctl_map))
+ return -EINVAL;
+
+ if (copy_from_user(&prctl_map, addr, sizeof(prctl_map)))
+ return -EFAULT;
+
+ error = validate_prctl_map(&prctl_map);
+ if (error)
+ return error;
+
+ if (prctl_map.auxv_size) {
+ memset(user_auxv, 0, sizeof(user_auxv));
+ if (copy_from_user(user_auxv,
+ (const void __user *)prctl_map.auxv,
+ prctl_map.auxv_size))
+ return -EFAULT;
+
+ /* Last entry must be AT_NULL as specification requires */
+ user_auxv[AT_VECTOR_SIZE - 2] = AT_NULL;
+ user_auxv[AT_VECTOR_SIZE - 1] = AT_NULL;
+ }
+
+ if (prctl_map.exe_fd != (u32)-1) {
+ error = prctl_set_mm_exe_file(mm, prctl_map.exe_fd);
+ if (error)
+ return error;
+ }
+
+ /*
+ * arg_lock protects concurent updates but we still need mmap_sem for
+ * read to exclude races with sys_brk.
+ */
+ down_read(&mm->mmap_sem);
+
+ /*
+ * We don't validate if these members are pointing to
+ * real present VMAs because application may have correspond
+ * VMAs already unmapped and kernel uses these members for statistics
+ * output in procfs mostly, except
+ *
+ * - @start_brk/@brk which are used in do_brk but kernel lookups
+ * for VMAs when updating these memvers so anything wrong written
+ * here cause kernel to swear at userspace program but won't lead
+ * to any problem in kernel itself
+ */
+
+ spin_lock(&mm->arg_lock);
+ mm->start_code = prctl_map.start_code;
+ mm->end_code = prctl_map.end_code;
+ mm->start_data = prctl_map.start_data;
+ mm->end_data = prctl_map.end_data;
+ mm->start_brk = prctl_map.start_brk;
+ mm->brk = prctl_map.brk;
+ mm->start_stack = prctl_map.start_stack;
+ mm->arg_start = prctl_map.arg_start;
+ mm->arg_end = prctl_map.arg_end;
+ mm->env_start = prctl_map.env_start;
+ mm->env_end = prctl_map.env_end;
+ spin_unlock(&mm->arg_lock);
+
+ /*
+ * Note this update of @saved_auxv is lockless thus
+ * if someone reads this member in procfs while we're
+ * updating -- it may get partly updated results. It's
+ * known and acceptable trade off: we leave it as is to
+ * not introduce additional locks here making the kernel
+ * more complex.
+ */
+ if (prctl_map.auxv_size)
+ memcpy(mm->saved_auxv, user_auxv, sizeof(user_auxv));
+
+ up_read(&mm->mmap_sem);
+ return 0;
+}
+#endif /* CONFIG_CHECKPOINT_RESTORE */
+
+static int prctl_set_auxv(struct mm_struct *mm, unsigned long addr,
+ unsigned long len)
+{
+ /*
+ * This doesn't move the auxiliary vector itself since it's pinned to
+ * mm_struct, but it permits filling the vector with new values. It's
+ * up to the caller to provide sane values here, otherwise userspace
+ * tools which use this vector might be unhappy.
+ */
+ unsigned long user_auxv[AT_VECTOR_SIZE];
+
+ if (len > sizeof(user_auxv))
+ return -EINVAL;
+
+ if (copy_from_user(user_auxv, (const void __user *)addr, len))
+ return -EFAULT;
+
+ /* Make sure the last entry is always AT_NULL */
+ user_auxv[AT_VECTOR_SIZE - 2] = 0;
+ user_auxv[AT_VECTOR_SIZE - 1] = 0;
+
+ BUILD_BUG_ON(sizeof(user_auxv) != sizeof(mm->saved_auxv));
+
+ task_lock(current);
+ memcpy(mm->saved_auxv, user_auxv, len);
+ task_unlock(current);
+
+ return 0;
+}
+
+static int prctl_set_mm(int opt, unsigned long addr,
+ unsigned long arg4, unsigned long arg5)
+{
+ struct mm_struct *mm = current->mm;
+ struct prctl_mm_map prctl_map;
+ struct vm_area_struct *vma;
+ int error;
+
+ if (arg5 || (arg4 && (opt != PR_SET_MM_AUXV &&
+ opt != PR_SET_MM_MAP &&
+ opt != PR_SET_MM_MAP_SIZE)))
+ return -EINVAL;
+
+#ifdef CONFIG_CHECKPOINT_RESTORE
+ if (opt == PR_SET_MM_MAP || opt == PR_SET_MM_MAP_SIZE)
+ return prctl_set_mm_map(opt, (const void __user *)addr, arg4);
+#endif
+
+ if (!capable(CAP_SYS_RESOURCE))
+ return -EPERM;
+
+ if (opt == PR_SET_MM_EXE_FILE)
+ return prctl_set_mm_exe_file(mm, (unsigned int)addr);
+
+ if (opt == PR_SET_MM_AUXV)
+ return prctl_set_auxv(mm, addr, arg4);
+
+ if (addr >= TASK_SIZE || addr < mmap_min_addr)
+ return -EINVAL;
+
+ error = -EINVAL;
+
+ down_write(&mm->mmap_sem);
+ vma = find_vma(mm, addr);
+
+ prctl_map.start_code = mm->start_code;
+ prctl_map.end_code = mm->end_code;
+ prctl_map.start_data = mm->start_data;
+ prctl_map.end_data = mm->end_data;
+ prctl_map.start_brk = mm->start_brk;
+ prctl_map.brk = mm->brk;
+ prctl_map.start_stack = mm->start_stack;
+ prctl_map.arg_start = mm->arg_start;
+ prctl_map.arg_end = mm->arg_end;
+ prctl_map.env_start = mm->env_start;
+ prctl_map.env_end = mm->env_end;
+ prctl_map.auxv = NULL;
+ prctl_map.auxv_size = 0;
+ prctl_map.exe_fd = -1;
+
+ switch (opt) {
+ case PR_SET_MM_START_CODE:
+ prctl_map.start_code = addr;
+ break;
+ case PR_SET_MM_END_CODE:
+ prctl_map.end_code = addr;
+ break;
+ case PR_SET_MM_START_DATA:
+ prctl_map.start_data = addr;
+ break;
+ case PR_SET_MM_END_DATA:
+ prctl_map.end_data = addr;
+ break;
+ case PR_SET_MM_START_STACK:
+ prctl_map.start_stack = addr;
+ break;
+ case PR_SET_MM_START_BRK:
+ prctl_map.start_brk = addr;
+ break;
+ case PR_SET_MM_BRK:
+ prctl_map.brk = addr;
+ break;
+ case PR_SET_MM_ARG_START:
+ prctl_map.arg_start = addr;
+ break;
+ case PR_SET_MM_ARG_END:
+ prctl_map.arg_end = addr;
+ break;
+ case PR_SET_MM_ENV_START:
+ prctl_map.env_start = addr;
+ break;
+ case PR_SET_MM_ENV_END:
+ prctl_map.env_end = addr;
+ break;
+ default:
+ goto out;
+ }
+
+ error = validate_prctl_map(&prctl_map);
+ if (error)
+ goto out;
+
+ switch (opt) {
+ /*
+ * If command line arguments and environment
+ * are placed somewhere else on stack, we can
+ * set them up here, ARG_START/END to setup
+ * command line argumets and ENV_START/END
+ * for environment.
+ */
+ case PR_SET_MM_START_STACK:
+ case PR_SET_MM_ARG_START:
+ case PR_SET_MM_ARG_END:
+ case PR_SET_MM_ENV_START:
+ case PR_SET_MM_ENV_END:
+ if (!vma) {
+ error = -EFAULT;
+ goto out;
+ }
+ }
+
+ mm->start_code = prctl_map.start_code;
+ mm->end_code = prctl_map.end_code;
+ mm->start_data = prctl_map.start_data;
+ mm->end_data = prctl_map.end_data;
+ mm->start_brk = prctl_map.start_brk;
+ mm->brk = prctl_map.brk;
+ mm->start_stack = prctl_map.start_stack;
+ mm->arg_start = prctl_map.arg_start;
+ mm->arg_end = prctl_map.arg_end;
+ mm->env_start = prctl_map.env_start;
+ mm->env_end = prctl_map.env_end;
+
+ error = 0;
+out:
+ up_write(&mm->mmap_sem);
+ return error;
+}
+
+#ifdef CONFIG_CHECKPOINT_RESTORE
+static int prctl_get_tid_address(struct task_struct *me, int __user **tid_addr)
+{
+ return put_user(me->clear_child_tid, tid_addr);
+}
+#else
+static int prctl_get_tid_address(struct task_struct *me, int __user **tid_addr)
+{
+ return -EINVAL;
+}
+#endif
+
+static int propagate_has_child_subreaper(struct task_struct *p, void *data)
+{
+ /*
+ * If task has has_child_subreaper - all its decendants
+ * already have these flag too and new decendants will
+ * inherit it on fork, skip them.
+ *
+ * If we've found child_reaper - skip descendants in
+ * it's subtree as they will never get out pidns.
+ */
+ if (p->signal->has_child_subreaper ||
+ is_child_reaper(task_pid(p)))
+ return 0;
+
+ p->signal->has_child_subreaper = 1;
+ return 1;
+}
+
+int __weak arch_prctl_spec_ctrl_get(struct task_struct *t, unsigned long which)
+{
+ return -EINVAL;
+}
+
+int __weak arch_prctl_spec_ctrl_set(struct task_struct *t, unsigned long which,
+ unsigned long ctrl)
+{
+ return -EINVAL;
+}
+
+SYSCALL_DEFINE5(prctl, int, option, unsigned long, arg2, unsigned long, arg3,
+ unsigned long, arg4, unsigned long, arg5)
+{
+ struct task_struct *me = current;
+ unsigned char comm[sizeof(me->comm)];
+ long error;
+
+ error = security_task_prctl(option, arg2, arg3, arg4, arg5);
+ if (error != -ENOSYS)
+ return error;
+
+ error = 0;
+ switch (option) {
+ case PR_SET_PDEATHSIG:
+ if (!valid_signal(arg2)) {
+ error = -EINVAL;
+ break;
+ }
+ me->pdeath_signal = arg2;
+ break;
+ case PR_GET_PDEATHSIG:
+ error = put_user(me->pdeath_signal, (int __user *)arg2);
+ break;
+ case PR_GET_DUMPABLE:
+ error = get_dumpable(me->mm);
+ break;
+ case PR_SET_DUMPABLE:
+ if (arg2 != SUID_DUMP_DISABLE && arg2 != SUID_DUMP_USER) {
+ error = -EINVAL;
+ break;
+ }
+ set_dumpable(me->mm, arg2);
+ break;
+
+ case PR_SET_UNALIGN:
+ error = SET_UNALIGN_CTL(me, arg2);
+ break;
+ case PR_GET_UNALIGN:
+ error = GET_UNALIGN_CTL(me, arg2);
+ break;
+ case PR_SET_FPEMU:
+ error = SET_FPEMU_CTL(me, arg2);
+ break;
+ case PR_GET_FPEMU:
+ error = GET_FPEMU_CTL(me, arg2);
+ break;
+ case PR_SET_FPEXC:
+ error = SET_FPEXC_CTL(me, arg2);
+ break;
+ case PR_GET_FPEXC:
+ error = GET_FPEXC_CTL(me, arg2);
+ break;
+ case PR_GET_TIMING:
+ error = PR_TIMING_STATISTICAL;
+ break;
+ case PR_SET_TIMING:
+ if (arg2 != PR_TIMING_STATISTICAL)
+ error = -EINVAL;
+ break;
+ case PR_SET_NAME:
+ comm[sizeof(me->comm) - 1] = 0;
+ if (strncpy_from_user(comm, (char __user *)arg2,
+ sizeof(me->comm) - 1) < 0)
+ return -EFAULT;
+ set_task_comm(me, comm);
+ proc_comm_connector(me);
+ break;
+ case PR_GET_NAME:
+ get_task_comm(comm, me);
+ if (copy_to_user((char __user *)arg2, comm, sizeof(comm)))
+ return -EFAULT;
+ break;
+ case PR_GET_ENDIAN:
+ error = GET_ENDIAN(me, arg2);
+ break;
+ case PR_SET_ENDIAN:
+ error = SET_ENDIAN(me, arg2);
+ break;
+ case PR_GET_SECCOMP:
+ error = prctl_get_seccomp();
+ break;
+ case PR_SET_SECCOMP:
+ error = prctl_set_seccomp(arg2, (char __user *)arg3);
+ break;
+ case PR_GET_TSC:
+ error = GET_TSC_CTL(arg2);
+ break;
+ case PR_SET_TSC:
+ error = SET_TSC_CTL(arg2);
+ break;
+ case PR_TASK_PERF_EVENTS_DISABLE:
+ error = perf_event_task_disable();
+ break;
+ case PR_TASK_PERF_EVENTS_ENABLE:
+ error = perf_event_task_enable();
+ break;
+ case PR_GET_TIMERSLACK:
+ if (current->timer_slack_ns > ULONG_MAX)
+ error = ULONG_MAX;
+ else
+ error = current->timer_slack_ns;
+ break;
+ case PR_SET_TIMERSLACK:
+ if (arg2 <= 0)
+ current->timer_slack_ns =
+ current->default_timer_slack_ns;
+ else
+ current->timer_slack_ns = arg2;
+ break;
+ case PR_MCE_KILL:
+ if (arg4 | arg5)
+ return -EINVAL;
+ switch (arg2) {
+ case PR_MCE_KILL_CLEAR:
+ if (arg3 != 0)
+ return -EINVAL;
+ current->flags &= ~PF_MCE_PROCESS;
+ break;
+ case PR_MCE_KILL_SET:
+ current->flags |= PF_MCE_PROCESS;
+ if (arg3 == PR_MCE_KILL_EARLY)
+ current->flags |= PF_MCE_EARLY;
+ else if (arg3 == PR_MCE_KILL_LATE)
+ current->flags &= ~PF_MCE_EARLY;
+ else if (arg3 == PR_MCE_KILL_DEFAULT)
+ current->flags &=
+ ~(PF_MCE_EARLY|PF_MCE_PROCESS);
+ else
+ return -EINVAL;
+ break;
+ default:
+ return -EINVAL;
+ }
+ break;
+ case PR_MCE_KILL_GET:
+ if (arg2 | arg3 | arg4 | arg5)
+ return -EINVAL;
+ if (current->flags & PF_MCE_PROCESS)
+ error = (current->flags & PF_MCE_EARLY) ?
+ PR_MCE_KILL_EARLY : PR_MCE_KILL_LATE;
+ else
+ error = PR_MCE_KILL_DEFAULT;
+ break;
+ case PR_SET_MM:
+ error = prctl_set_mm(arg2, arg3, arg4, arg5);
+ break;
+ case PR_GET_TID_ADDRESS:
+ error = prctl_get_tid_address(me, (int __user **)arg2);
+ break;
+ case PR_SET_CHILD_SUBREAPER:
+ me->signal->is_child_subreaper = !!arg2;
+ if (!arg2)
+ break;
+
+ walk_process_tree(me, propagate_has_child_subreaper, NULL);
+ break;
+ case PR_GET_CHILD_SUBREAPER:
+ error = put_user(me->signal->is_child_subreaper,
+ (int __user *)arg2);
+ break;
+ case PR_SET_NO_NEW_PRIVS:
+ if (arg2 != 1 || arg3 || arg4 || arg5)
+ return -EINVAL;
+
+ task_set_no_new_privs(current);
+ break;
+ case PR_GET_NO_NEW_PRIVS:
+ if (arg2 || arg3 || arg4 || arg5)
+ return -EINVAL;
+ return task_no_new_privs(current) ? 1 : 0;
+ case PR_GET_THP_DISABLE:
+ if (arg2 || arg3 || arg4 || arg5)
+ return -EINVAL;
+ error = !!test_bit(MMF_DISABLE_THP, &me->mm->flags);
+ break;
+ case PR_SET_THP_DISABLE:
+ if (arg3 || arg4 || arg5)
+ return -EINVAL;
+ if (down_write_killable(&me->mm->mmap_sem))
+ return -EINTR;
+ if (arg2)
+ set_bit(MMF_DISABLE_THP, &me->mm->flags);
+ else
+ clear_bit(MMF_DISABLE_THP, &me->mm->flags);
+ up_write(&me->mm->mmap_sem);
+ break;
+ case PR_MPX_ENABLE_MANAGEMENT:
+ if (arg2 || arg3 || arg4 || arg5)
+ return -EINVAL;
+ error = MPX_ENABLE_MANAGEMENT();
+ break;
+ case PR_MPX_DISABLE_MANAGEMENT:
+ if (arg2 || arg3 || arg4 || arg5)
+ return -EINVAL;
+ error = MPX_DISABLE_MANAGEMENT();
+ break;
+ case PR_SET_FP_MODE:
+ error = SET_FP_MODE(me, arg2);
+ break;
+ case PR_GET_FP_MODE:
+ error = GET_FP_MODE(me);
+ break;
+ case PR_SVE_SET_VL:
+ error = SVE_SET_VL(arg2);
+ break;
+ case PR_SVE_GET_VL:
+ error = SVE_GET_VL();
+ break;
+ case PR_GET_SPECULATION_CTRL:
+ if (arg3 || arg4 || arg5)
+ return -EINVAL;
+ error = arch_prctl_spec_ctrl_get(me, arg2);
+ break;
+ case PR_SET_SPECULATION_CTRL:
+ if (arg4 || arg5)
+ return -EINVAL;
+ error = arch_prctl_spec_ctrl_set(me, arg2, arg3);
+ break;
+ default:
+ error = -EINVAL;
+ break;
+ }
+ return error;
+}
+
+SYSCALL_DEFINE3(getcpu, unsigned __user *, cpup, unsigned __user *, nodep,
+ struct getcpu_cache __user *, unused)
+{
+ int err = 0;
+ int cpu = raw_smp_processor_id();
+
+ if (cpup)
+ err |= put_user(cpu, cpup);
+ if (nodep)
+ err |= put_user(cpu_to_node(cpu), nodep);
+ return err ? -EFAULT : 0;
+}
+
+/**
+ * do_sysinfo - fill in sysinfo struct
+ * @info: pointer to buffer to fill
+ */
+static int do_sysinfo(struct sysinfo *info)
+{
+ unsigned long mem_total, sav_total;
+ unsigned int mem_unit, bitcount;
+ struct timespec64 tp;
+
+ memset(info, 0, sizeof(struct sysinfo));
+
+ ktime_get_boottime_ts64(&tp);
+ info->uptime = tp.tv_sec + (tp.tv_nsec ? 1 : 0);
+
+ get_avenrun(info->loads, 0, SI_LOAD_SHIFT - FSHIFT);
+
+ info->procs = nr_threads;
+
+ si_meminfo(info);
+ si_swapinfo(info);
+
+ /*
+ * If the sum of all the available memory (i.e. ram + swap)
+ * is less than can be stored in a 32 bit unsigned long then
+ * we can be binary compatible with 2.2.x kernels. If not,
+ * well, in that case 2.2.x was broken anyways...
+ *
+ * -Erik Andersen <andersee@debian.org>
+ */
+
+ mem_total = info->totalram + info->totalswap;
+ if (mem_total < info->totalram || mem_total < info->totalswap)
+ goto out;
+ bitcount = 0;
+ mem_unit = info->mem_unit;
+ while (mem_unit > 1) {
+ bitcount++;
+ mem_unit >>= 1;
+ sav_total = mem_total;
+ mem_total <<= 1;
+ if (mem_total < sav_total)
+ goto out;
+ }
+
+ /*
+ * If mem_total did not overflow, multiply all memory values by
+ * info->mem_unit and set it to 1. This leaves things compatible
+ * with 2.2.x, and also retains compatibility with earlier 2.4.x
+ * kernels...
+ */
+
+ info->mem_unit = 1;
+ info->totalram <<= bitcount;
+ info->freeram <<= bitcount;
+ info->sharedram <<= bitcount;
+ info->bufferram <<= bitcount;
+ info->totalswap <<= bitcount;
+ info->freeswap <<= bitcount;
+ info->totalhigh <<= bitcount;
+ info->freehigh <<= bitcount;
+
+out:
+ return 0;
+}
+
+SYSCALL_DEFINE1(sysinfo, struct sysinfo __user *, info)
+{
+ struct sysinfo val;
+
+ do_sysinfo(&val);
+
+ if (copy_to_user(info, &val, sizeof(struct sysinfo)))
+ return -EFAULT;
+
+ return 0;
+}
+
+#ifdef CONFIG_COMPAT
+struct compat_sysinfo {
+ s32 uptime;
+ u32 loads[3];
+ u32 totalram;
+ u32 freeram;
+ u32 sharedram;
+ u32 bufferram;
+ u32 totalswap;
+ u32 freeswap;
+ u16 procs;
+ u16 pad;
+ u32 totalhigh;
+ u32 freehigh;
+ u32 mem_unit;
+ char _f[20-2*sizeof(u32)-sizeof(int)];
+};
+
+COMPAT_SYSCALL_DEFINE1(sysinfo, struct compat_sysinfo __user *, info)
+{
+ struct sysinfo s;
+
+ do_sysinfo(&s);
+
+ /* Check to see if any memory value is too large for 32-bit and scale
+ * down if needed
+ */
+ if (upper_32_bits(s.totalram) || upper_32_bits(s.totalswap)) {
+ int bitcount = 0;
+
+ while (s.mem_unit < PAGE_SIZE) {
+ s.mem_unit <<= 1;
+ bitcount++;
+ }
+
+ s.totalram >>= bitcount;
+ s.freeram >>= bitcount;
+ s.sharedram >>= bitcount;
+ s.bufferram >>= bitcount;
+ s.totalswap >>= bitcount;
+ s.freeswap >>= bitcount;
+ s.totalhigh >>= bitcount;
+ s.freehigh >>= bitcount;
+ }
+
+ if (!access_ok(VERIFY_WRITE, info, sizeof(struct compat_sysinfo)) ||
+ __put_user(s.uptime, &info->uptime) ||
+ __put_user(s.loads[0], &info->loads[0]) ||
+ __put_user(s.loads[1], &info->loads[1]) ||
+ __put_user(s.loads[2], &info->loads[2]) ||
+ __put_user(s.totalram, &info->totalram) ||
+ __put_user(s.freeram, &info->freeram) ||
+ __put_user(s.sharedram, &info->sharedram) ||
+ __put_user(s.bufferram, &info->bufferram) ||
+ __put_user(s.totalswap, &info->totalswap) ||
+ __put_user(s.freeswap, &info->freeswap) ||
+ __put_user(s.procs, &info->procs) ||
+ __put_user(s.totalhigh, &info->totalhigh) ||
+ __put_user(s.freehigh, &info->freehigh) ||
+ __put_user(s.mem_unit, &info->mem_unit))
+ return -EFAULT;
+
+ return 0;
+}
+#endif /* CONFIG_COMPAT */