Initial import

1 files changed, 2408 insertions, 0 deletions

diff --git a/kernel/sys.c b/kernel/sys.c
new file mode 100644
index 000000000..a4e372b79
--- /dev/null
+++ b/kernel/sys.c
@@ -0,0 +1,2408 @@
+/*
+ *  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/rcupdate.h>
+#include <linux/uidgid.h>
+#include <linux/cred.h>
+
+#include <linux/kmsg_dump.h>
+/* Move somewhere else to avoid recompiling? */
+#include <generated/utsrelease.h>
+
+#include <asm/uaccess.h>
+#include <asm/io.h>
+#include <asm/unistd.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(a)	(-EINVAL)
+#endif
+#ifndef MPX_DISABLE_MANAGEMENT
+# define MPX_DISABLE_MANAGEMENT(a)	(-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
+
+/*
+ * 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_OVERFLOWUID;
+
+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))
+				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)) {
+				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
+SYSCALL_DEFINE2(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;
+}
+
+/*
+ * setgid() is implemented like SysV w/ SAVED_IDS
+ *
+ * SMP: Same implicit races as above.
+ */
+SYSCALL_DEFINE1(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;
+}
+
+/*
+ * 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.
+ */
+SYSCALL_DEFINE2(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;
+}
+
+/*
+ * 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.
+ */
+SYSCALL_DEFINE1(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;
+}
+
+
+/*
+ * This function implements a generic ability to update ruid, euid,
+ * and suid.  This allows you to implement the 4.4 compatible seteuid().
+ */
+SYSCALL_DEFINE3(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(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.
+ */
+SYSCALL_DEFINE3(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(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..
+ */
+SYSCALL_DEFINE1(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;
+}
+
+/*
+ * Samma på svenska..
+ */
+SYSCALL_DEFINE1(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;
+}
+#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());
+}
+
+void do_sys_times(struct tms *tms)
+{
+	cputime_t tgutime, tgstime, cutime, cstime;
+
+	thread_group_cputime_adjusted(current, &tgutime, &tgstime);
+	cutime = current->signal->cutime;
+	cstime = current->signal->cstime;
+	tms->tms_utime = cputime_to_clock_t(tgutime);
+	tms->tms_stime = cputime_to_clock_t(tgstime);
+	tms->tms_cutime = cputime_to_clock_t(cutime);
+	tms->tms_cstime = cputime_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());
+}
+
+/*
+ * 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;
+}
+
+SYSCALL_DEFINE1(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;
+}
+
+#ifdef __ARCH_WANT_SYS_GETPGRP
+
+SYSCALL_DEFINE0(getpgrp)
+{
+	return sys_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);
+}
+
+SYSCALL_DEFINE0(setsid)
+{
+	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;
+}
+
+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)
+{
+	int errno = 0;
+
+	down_read(&uts_sem);
+	if (copy_to_user(name, utsname(), sizeof *name))
+		errno = -EFAULT;
+	up_read(&uts_sem);
+
+	if (!errno && override_release(name->release, sizeof(name->release)))
+		errno = -EFAULT;
+	if (!errno && override_architecture(name))
+		errno = -EFAULT;
+	return errno;
+}
+
+#ifdef __ARCH_WANT_SYS_OLD_UNAME
+/*
+ * Old cruft
+ */
+SYSCALL_DEFINE1(uname, struct old_utsname __user *, name)
+{
+	int error = 0;
+
+	if (!name)
+		return -EFAULT;
+
+	down_read(&uts_sem);
+	if (copy_to_user(name, utsname(), sizeof(*name)))
+		error = -EFAULT;
+	up_read(&uts_sem);
+
+	if (!error && override_release(name->release, sizeof(name->release)))
+		error = -EFAULT;
+	if (!error && override_architecture(name))
+		error = -EFAULT;
+	return error;
+}
+
+SYSCALL_DEFINE1(olduname, struct oldold_utsname __user *, name)
+{
+	int error;
+
+	if (!name)
+		return -EFAULT;
+	if (!access_ok(VERIFY_WRITE, name, sizeof(struct oldold_utsname)))
+		return -EFAULT;
+
+	down_read(&uts_sem);
+	error = __copy_to_user(&name->sysname, &utsname()->sysname,
+			       __OLD_UTS_LEN);
+	error |= __put_user(0, name->sysname + __OLD_UTS_LEN);
+	error |= __copy_to_user(&name->nodename, &utsname()->nodename,
+				__OLD_UTS_LEN);
+	error |= __put_user(0, name->nodename + __OLD_UTS_LEN);
+	error |= __copy_to_user(&name->release, &utsname()->release,
+				__OLD_UTS_LEN);
+	error |= __put_user(0, name->release + __OLD_UTS_LEN);
+	error |= __copy_to_user(&name->version, &utsname()->version,
+				__OLD_UTS_LEN);
+	error |= __put_user(0, name->version + __OLD_UTS_LEN);
+	error |= __copy_to_user(&name->machine, &utsname()->machine,
+				__OLD_UTS_LEN);
+	error |= __put_user(0, name->machine + __OLD_UTS_LEN);
+	up_read(&uts_sem);
+
+	if (!error && override_architecture(name))
+		error = -EFAULT;
+	if (!error && override_release(name->release, sizeof(name->release)))
+		error = -EFAULT;
+	return error ? -EFAULT : 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;
+	down_write(&uts_sem);
+	errno = -EFAULT;
+	if (!copy_from_user(tmp, name, len)) {
+		struct new_utsname *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, errno;
+	struct new_utsname *u;
+
+	if (len < 0)
+		return -EINVAL;
+	down_read(&uts_sem);
+	u = utsname();
+	i = 1 + strlen(u->nodename);
+	if (i > len)
+		i = len;
+	errno = 0;
+	if (copy_to_user(name, u->nodename, i))
+		errno = -EFAULT;
+	up_read(&uts_sem);
+	return errno;
+}
+
+#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;
+
+	down_write(&uts_sem);
+	errno = -EFAULT;
+	if (!copy_from_user(tmp, name, len)) {
+		struct new_utsname *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 __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;
+
+	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;
+}
+
+#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->group_leader,
+					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)
+		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)
+{
+	const struct cred *cred = current_cred(), *tcred;
+
+	if (current == task)
+		return 0;
+
+	tcred = __task_cred(task);
+	if (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))
+		return 0;
+	if (ns_capable(tcred->user_ns, CAP_SYS_RESOURCE))
+		return 0;
+
+	return -EPERM;
+}
+
+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;
+	int ret;
+
+	if (new_rlim) {
+		if (copy_from_user(&new64, new_rlim, sizeof(new64)))
+			return -EFAULT;
+		rlim64_to_rlim(&new64, &new);
+	}
+
+	rcu_read_lock();
+	tsk = pid ? find_task_by_vpid(pid) : current;
+	if (!tsk) {
+		rcu_read_unlock();
+		return -ESRCH;
+	}
+	ret = check_prlimit_permission(tsk);
+	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);
+}
+
+static void k_getrusage(struct task_struct *p, int who, struct rusage *r)
+{
+	struct task_struct *t;
+	unsigned long flags;
+	cputime_t 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:
+	cputime_to_timeval(utime, &r->ru_utime);
+	cputime_to_timeval(stime, &r->ru_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 */
+}
+
+int getrusage(struct task_struct *p, int who, struct rusage __user *ru)
+{
+	struct rusage r;
+
+	k_getrusage(p, who, &r);
+	return copy_to_user(ru, &r, sizeof(r)) ? -EFAULT : 0;
+}
+
+SYSCALL_DEFINE2(getrusage, int, who, struct rusage __user *, ru)
+{
+	if (who != RUSAGE_SELF && who != RUSAGE_CHILDREN &&
+	    who != RUSAGE_THREAD)
+		return -EINVAL;
+	return getrusage(current, who, ru);
+}
+
+#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;
+
+	k_getrusage(current, who, &r);
+	return put_compat_rusage(&r, ru);
+}
+#endif
+
+SYSCALL_DEFINE1(umask, int, mask)
+{
+	mask = xchg(&current->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)	||
+	    exe.file->f_path.mnt->mnt_flags & MNT_NOEXEC)
+		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);
+	}
+
+	/*
+	 * The symlink can be changed only once, just to disallow arbitrary
+	 * transitions malicious software might bring in. This means one
+	 * could make a snapshot over all processes running and monitor
+	 * /proc/pid/exe changes to notice unusual activity if needed.
+	 */
+	err = -EPERM;
+	if (test_and_set_bit(MMF_EXE_FILE_CHANGED, &mm->flags))
+		goto exit;
+
+	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;
+}
+
+#ifdef CONFIG_CHECKPOINT_RESTORE
+/*
+ * 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 root should
+	 * be allowed to.
+	 */
+	if (prctl_map->exe_fd != (u32)-1) {
+		struct user_namespace *ns = current_user_ns();
+		const struct cred *cred = current_cred();
+
+		if (!uid_eq(cred->uid, make_kuid(ns, 0)) ||
+		    !gid_eq(cred->gid, make_kgid(ns, 0)))
+			goto out;
+	}
+
+	error = 0;
+out:
+	return error;
+}
+
+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);
+	down_read(&mm->mmap_sem);
+	if (error)
+		goto out;
+
+	/*
+	 * 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
+	 */
+
+	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;
+
+	/*
+	 * 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));
+
+	error = 0;
+out:
+	up_read(&mm->mmap_sem);
+	return error;
+}
+#endif /* CONFIG_CHECKPOINT_RESTORE */
+
+static int prctl_set_mm(int opt, unsigned long addr,
+			unsigned long arg4, unsigned long arg5)
+{
+	struct mm_struct *mm = current->mm;
+	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 (addr >= TASK_SIZE || addr < mmap_min_addr)
+		return -EINVAL;
+
+	error = -EINVAL;
+
+	down_read(&mm->mmap_sem);
+	vma = find_vma(mm, addr);
+
+	switch (opt) {
+	case PR_SET_MM_START_CODE:
+		mm->start_code = addr;
+		break;
+	case PR_SET_MM_END_CODE:
+		mm->end_code = addr;
+		break;
+	case PR_SET_MM_START_DATA:
+		mm->start_data = addr;
+		break;
+	case PR_SET_MM_END_DATA:
+		mm->end_data = addr;
+		break;
+
+	case PR_SET_MM_START_BRK:
+		if (addr <= mm->end_data)
+			goto out;
+
+		if (check_data_rlimit(rlimit(RLIMIT_DATA), mm->brk, addr,
+				      mm->end_data, mm->start_data))
+			goto out;
+
+		mm->start_brk = addr;
+		break;
+
+	case PR_SET_MM_BRK:
+		if (addr <= mm->end_data)
+			goto out;
+
+		if (check_data_rlimit(rlimit(RLIMIT_DATA), addr, mm->start_brk,
+				      mm->end_data, mm->start_data))
+			goto out;
+
+		mm->brk = addr;
+		break;
+
+	/*
+	 * 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;
+		}
+		if (opt == PR_SET_MM_START_STACK)
+			mm->start_stack = addr;
+		else if (opt == PR_SET_MM_ARG_START)
+			mm->arg_start = addr;
+		else if (opt == PR_SET_MM_ARG_END)
+			mm->arg_end = addr;
+		else if (opt == PR_SET_MM_ENV_START)
+			mm->env_start = addr;
+		else if (opt == PR_SET_MM_ENV_END)
+			mm->env_end = addr;
+		break;
+
+	/*
+	 * This doesn't move auxiliary vector itself
+	 * since it's pinned to mm_struct, but allow
+	 * to fill vector with new values. It's up
+	 * to a caller to provide sane values here
+	 * otherwise user space tools which use this
+	 * vector might be unhappy.
+	 */
+	case PR_SET_MM_AUXV: {
+		unsigned long user_auxv[AT_VECTOR_SIZE];
+
+		if (arg4 > sizeof(user_auxv))
+			goto out;
+		up_read(&mm->mmap_sem);
+
+		if (copy_from_user(user_auxv, (const void __user *)addr, arg4))
+			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, arg4);
+		task_unlock(current);
+
+		return 0;
+	}
+	default:
+		goto out;
+	}
+
+	error = 0;
+out:
+	up_read(&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
+
+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:
+		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;
+		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 = !!(me->mm->def_flags & VM_NOHUGEPAGE);
+		break;
+	case PR_SET_THP_DISABLE:
+		if (arg3 || arg4 || arg5)
+			return -EINVAL;
+		down_write(&me->mm->mmap_sem);
+		if (arg2)
+			me->mm->def_flags |= VM_NOHUGEPAGE;
+		else
+			me->mm->def_flags &= ~VM_NOHUGEPAGE;
+		up_write(&me->mm->mmap_sem);
+		break;
+	case PR_MPX_ENABLE_MANAGEMENT:
+		if (arg2 || arg3 || arg4 || arg5)
+			return -EINVAL;
+		error = MPX_ENABLE_MANAGEMENT(me);
+		break;
+	case PR_MPX_DISABLE_MANAGEMENT:
+		if (arg2 || arg3 || arg4 || arg5)
+			return -EINVAL;
+		error = MPX_DISABLE_MANAGEMENT(me);
+		break;
+	case PR_SET_FP_MODE:
+		error = SET_FP_MODE(me, arg2);
+		break;
+	case PR_GET_FP_MODE:
+		error = GET_FP_MODE(me);
+		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 timespec tp;
+
+	memset(info, 0, sizeof(struct sysinfo));
+
+	get_monotonic_boottime(&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 */