From e59d16965ca38df91c4d9390d8eb5a62d7739589 Mon Sep 17 00:00:00 2001 From: Auke Kok Date: Fri, 26 May 2006 09:35:28 -0700 Subject: ixgb: fix smp polling race condition Moved interrupt masking to before requesting the interrupt from the OS. Moved interrupt enable to after netif_poll_enable. This fixes a racy BUG() where polling would be running on another CPU at the same time that netif_poll_enable would run. Signed-off-by: Jesse Brandeburg Signed-off-by: Auke Kok Signed-off-by: John Ronciak --- drivers/net/ixgb/ixgb_main.c | 9 +++++---- 1 file changed, 5 insertions(+), 4 deletions(-) (limited to 'drivers') diff --git a/drivers/net/ixgb/ixgb_main.c b/drivers/net/ixgb/ixgb_main.c index 0a0c876dcbdd..954894b5308c 100644 --- a/drivers/net/ixgb/ixgb_main.c +++ b/drivers/net/ixgb/ixgb_main.c @@ -247,6 +247,9 @@ ixgb_up(struct ixgb_adapter *adapter) ixgb_configure_rx(adapter); ixgb_alloc_rx_buffers(adapter); + /* disable interrupts and get the hardware into a known state */ + IXGB_WRITE_REG(&adapter->hw, IMC, 0xffffffff); + #ifdef CONFIG_PCI_MSI { boolean_t pcix = (IXGB_READ_REG(&adapter->hw, STATUS) & @@ -272,9 +275,6 @@ ixgb_up(struct ixgb_adapter *adapter) return err; } - /* disable interrupts and get the hardware into a known state */ - IXGB_WRITE_REG(&adapter->hw, IMC, 0xffffffff); - if((hw->max_frame_size != max_frame) || (hw->max_frame_size != (IXGB_READ_REG(hw, MFS) >> IXGB_MFS_SHIFT))) { @@ -295,11 +295,12 @@ ixgb_up(struct ixgb_adapter *adapter) } mod_timer(&adapter->watchdog_timer, jiffies); - ixgb_irq_enable(adapter); #ifdef CONFIG_IXGB_NAPI netif_poll_enable(netdev); #endif + ixgb_irq_enable(adapter); + return 0; } -- cgit v1.2.2 gm'>pgm The LITMUS^RT kernel.Bjoern Brandenburg
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/*
 *  linux/kernel/sys.c
 *
 *  Copyright (C) 1991, 1992  Linus Torvalds
 */

#include <linux/module.h>
#include <linux/mm.h>
#include <linux/utsname.h>
#include <linux/mman.h>
#include <linux/notifier.h>
#include <linux/reboot.h>
#include <linux/prctl.h>
#include <linux/highuid.h>
#include <linux/fs.h>
#include <linux/perf_event.h>
#include <linux/resource.h>
#include <linux/kernel.h>
#include <linux/kexec.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/compat.h>
#include <linux/syscalls.h>
#include <linux/kprobes.h>
#include <linux/user_namespace.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

/*
 * 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;

#ifdef CONFIG_UID16
EXPORT_SYMBOL(overflowuid);
EXPORT_SYMBOL(overflowgid);
#endif

/*
 * 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);

/*
 * this indicates whether you can reboot with ctrl-alt-del: the default is yes
 */

int C_A_D = 1;
struct pid *cad_pid;
EXPORT_SYMBOL(cad_pid);

/*
 * If set, this is used for preparing the system to power off.
 */

void (*pm_power_off_prepare)(void);

/*
 * 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)
{
	const struct cred *cred = current_cred(), *pcred = __task_cred(p);
	int no_nice;

	if (pcred->uid  != cred->euid &&
	    pcred->euid != cred->euid && !capable(CAP_SYS_NICE)) {
		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;

	if (which > PRIO_USER || which < PRIO_PROCESS)
		goto out;

	/* normalize: avoid signed division (rounding problems) */
	error = -ESRCH;
	if (niceval < -20)
		niceval = -20;
	if (niceval > 19)
		niceval = 19;

	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:
			user = (struct user_struct *) cred->user;
			if (!who)
				who = cred->uid;
			else if ((who != cred->uid) &&
				 !(user = find_user(who)))
				goto out_unlock;	/* No processes for this user */

			do_each_thread(g, p) {
				if (__task_cred(p)->uid == who)
					error = set_one_prio(p, niceval, error);
			} while_each_thread(g, p);
			if (who != 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;

	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 = 20 - 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 = 20 - task_nice(p);
				if (niceval > retval)
					retval = niceval;
			} while_each_pid_thread(pgrp, PIDTYPE_PGID, p);
			break;
		case PRIO_USER:
			user = (struct user_struct *) cred->user;
			if (!who)
				who = cred->uid;
			else if ((who != cred->uid) &&
				 !(user = find_user(who)))
				goto out_unlock;	/* No processes for this user */

			do_each_thread(g, p) {
				if (__task_cred(p)->uid == who) {
					niceval = 20 - task_nice(p);
					if (niceval > retval)
						retval = niceval;
				}
			} while_each_thread(g, p);
			if (who != cred->uid)
				free_uid(user);		/* for find_user() */
			break;
	}
out_unlock:
	read_unlock(&tasklist_lock);
	rcu_read_unlock();

	return retval;
}

/**
 *	emergency_restart - reboot the system
 *
 *	Without shutting down any hardware or taking any locks
 *	reboot the system.  This is called when we know we are in
 *	trouble so this is our best effort to reboot.  This is
 *	safe to call in interrupt context.
 */
void emergency_restart(void)
{
	machine_emergency_restart();
}
EXPORT_SYMBOL_GPL(emergency_restart);

void kernel_restart_prepare(char *cmd)
{
	blocking_notifier_call_chain(&reboot_notifier_list, SYS_RESTART, cmd);
	system_state = SYSTEM_RESTART;
	device_shutdown();
	sysdev_shutdown();
}

/**
 *	kernel_restart - reboot the system
 *	@cmd: pointer to buffer containing command to execute for restart
 *		or %NULL
 *
 *	Shutdown everything and perform a clean reboot.
 *	This is not safe to call in interrupt context.
 */
void kernel_restart(char *cmd)
{
	kernel_restart_prepare(cmd);
	if (!cmd)
		printk(KERN_EMERG "Restarting system.\n");
	else
		printk(KERN_EMERG "Restarting system with command '%s'.\n", cmd);
	machine_restart(cmd);
}
EXPORT_SYMBOL_GPL(kernel_restart);

static void kernel_shutdown_prepare(enum system_states state)
{
	blocking_notifier_call_chain(&reboot_notifier_list,
		(state == SYSTEM_HALT)?SYS_HALT:SYS_POWER_OFF, NULL);
	system_state = state;
	device_shutdown();
}
/**
 *	kernel_halt - halt the system
 *
 *	Shutdown everything and perform a clean system halt.
 */
void kernel_halt(void)
{
	kernel_shutdown_prepare(SYSTEM_HALT);
	sysdev_shutdown();
	printk(KERN_EMERG "System halted.\n");
	machine_halt();
}

EXPORT_SYMBOL_GPL(kernel_halt);

/**
 *	kernel_power_off - power_off the system
 *
 *	Shutdown everything and perform a clean system power_off.
 */
void kernel_power_off(void)
{
	kernel_shutdown_prepare(SYSTEM_POWER_OFF);
	if (pm_power_off_prepare)
		pm_power_off_prepare();
	disable_nonboot_cpus();
	sysdev_shutdown();
	printk(KERN_EMERG "Power down.\n");
	machine_power_off();
}
EXPORT_SYMBOL_GPL(kernel_power_off);

static DEFINE_MUTEX(reboot_mutex);

/*
 * Reboot system call: for obvious reasons only root may call it,
 * and even root needs to set up some magic numbers in the registers
 * so that some mistake won't make this reboot the whole machine.
 * You can also set the meaning of the ctrl-alt-del-key here.
 *
 * reboot doesn't sync: do that yourself before calling this.
 */
SYSCALL_DEFINE4(reboot, int, magic1, int, magic2, unsigned int, cmd,
		void __user *, arg)
{
	char buffer[256];
	int ret = 0;

	/* We only trust the superuser with rebooting the system. */
	if (!capable(CAP_SYS_BOOT))
		return -EPERM;

	/* For safety, we require "magic" arguments. */
	if (magic1 != LINUX_REBOOT_MAGIC1 ||
	    (magic2 != LINUX_REBOOT_MAGIC2 &&
	                magic2 != LINUX_REBOOT_MAGIC2A &&
			magic2 != LINUX_REBOOT_MAGIC2B &&
	                magic2 != LINUX_REBOOT_MAGIC2C))
		return -EINVAL;

	/* Instead of trying to make the power_off code look like
	 * halt when pm_power_off is not set do it the easy way.
	 */
	if ((cmd == LINUX_REBOOT_CMD_POWER_OFF) && !pm_power_off)
		cmd = LINUX_REBOOT_CMD_HALT;

	mutex_lock(&reboot_mutex);
	switch (cmd) {
	case LINUX_REBOOT_CMD_RESTART:
		kernel_restart(NULL);
		break;

	case LINUX_REBOOT_CMD_CAD_ON:
		C_A_D = 1;
		break;

	case LINUX_REBOOT_CMD_CAD_OFF:
		C_A_D = 0;
		break;

	case LINUX_REBOOT_CMD_HALT:
		kernel_halt();
		do_exit(0);
		panic("cannot halt");

	case LINUX_REBOOT_CMD_POWER_OFF:
		kernel_power_off();
		do_exit(0);
		break;

	case LINUX_REBOOT_CMD_RESTART2:
		if (strncpy_from_user(&buffer[0], arg, sizeof(buffer) - 1) < 0) {
			ret = -EFAULT;
			break;
		}
		buffer[sizeof(buffer) - 1] = '\0';

		kernel_restart(buffer);
		break;

#ifdef CONFIG_KEXEC
	case LINUX_REBOOT_CMD_KEXEC:
		ret = kernel_kexec();
		break;
#endif

#ifdef CONFIG_HIBERNATION
	case LINUX_REBOOT_CMD_SW_SUSPEND:
		ret = hibernate();
		break;
#endif

	default:
		ret = -EINVAL;
		break;
	}
	mutex_unlock(&reboot_mutex);
	return ret;
}

static void deferred_cad(struct work_struct *dummy)
{
	kernel_restart(NULL);
}

/*
 * This function gets called by ctrl-alt-del - ie the keyboard interrupt.
 * As it's called within an interrupt, it may NOT sync: the only choice
 * is whether to reboot at once, or just ignore the ctrl-alt-del.
 */
void ctrl_alt_del(void)
{
	static DECLARE_WORK(cad_work, deferred_cad);

	if (C_A_D)
		schedule_work(&cad_work);
	else
		kill_cad_pid(SIGINT, 1);
}
	
/*
 * 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).
 */
SYSCALL_DEFINE2(setregid, gid_t, rgid, gid_t, egid)
{
	const struct cred *old;
	struct cred *new;
	int retval;

	new = prepare_creds();
	if (!new)
		return -ENOMEM;
	old = current_cred();

	retval = security_task_setgid(rgid, egid, (gid_t)-1, LSM_SETID_RE);
	if (retval)
		goto error;

	retval = -EPERM;
	if (rgid != (gid_t) -1) {
		if (old->gid == rgid ||
		    old->egid == rgid ||
		    capable(CAP_SETGID))
			new->gid = rgid;
		else
			goto error;
	}
	if (egid != (gid_t) -1) {
		if (old->gid == egid ||
		    old->egid == egid ||
		    old->sgid == egid ||
		    capable(CAP_SETGID))
			new->egid = egid;
		else
			goto error;
	}

	if (rgid != (gid_t) -1 ||
	    (egid != (gid_t) -1 && egid != 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)
{
	const struct cred *old;
	struct cred *new;
	int retval;

	new = prepare_creds();
	if (!new)
		return -ENOMEM;
	old = current_cred();

	retval = security_task_setgid(gid, (gid_t)-1, (gid_t)-1, LSM_SETID_ID);
	if (retval)
		goto error;

	retval = -EPERM;
	if (capable(CAP_SETGID))
		new->gid = new->egid = new->sgid = new->fsgid = gid;
	else if (gid == old->gid || gid == old->sgid)
		new->egid = new->fsgid = gid;
	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(current_user_ns(), new->uid);
	if (!new_user)
		return -EAGAIN;

	if (atomic_read(&new_user->processes) >= rlimit(RLIMIT_NPROC) &&
			new_user != INIT_USER) {
		free_uid(new_user);
		return -EAGAIN;
	}

	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)
{
	const struct cred *old;
	struct cred *new;
	int retval;

	new = prepare_creds();
	if (!new)
		return -ENOMEM;
	old = current_cred();

	retval = security_task_setuid(ruid, euid, (uid_t)-1, LSM_SETID_RE);
	if (retval)
		goto error;

	retval = -EPERM;
	if (ruid != (uid_t) -1) {
		new->uid = ruid;
		if (old->uid != ruid &&
		    old->euid != ruid &&
		    !capable(CAP_SETUID))
			goto error;
	}

	if (euid != (uid_t) -1) {
		new->euid = euid;
		if (old->uid != euid &&
		    old->euid != euid &&
		    old->suid != euid &&
		    !capable(CAP_SETUID))
			goto error;
	}

	if (new->uid != old->uid) {
		retval = set_user(new);
		if (retval < 0)
			goto error;
	}
	if (ruid != (uid_t) -1 ||
	    (euid != (uid_t) -1 && euid != 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)
{
	const struct cred *old;
	struct cred *new;
	int retval;

	new = prepare_creds();
	if (!new)
		return -ENOMEM;
	old = current_cred();

	retval = security_task_setuid(uid, (uid_t)-1, (uid_t)-1, LSM_SETID_ID);
	if (retval)
		goto error;

	retval = -EPERM;
	if (capable(CAP_SETUID)) {
		new->suid = new->uid = uid;
		if (uid != old->uid) {
			retval = set_user(new);
			if (retval < 0)
				goto error;
		}
	} else if (uid != old->uid && uid != new->suid) {
		goto error;
	}

	new->fsuid = new->euid = uid;

	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)
{
	const struct cred *old;
	struct cred *new;
	int retval;

	new = prepare_creds();
	if (!new)
		return -ENOMEM;

	retval = security_task_setuid(ruid, euid, suid, LSM_SETID_RES);
	if (retval)
		goto error;
	old = current_cred();

	retval = -EPERM;
	if (!capable(CAP_SETUID)) {
		if (ruid != (uid_t) -1 && ruid != old->uid &&
		    ruid != old->euid  && ruid != old->suid)
			goto error;
		if (euid != (uid_t) -1 && euid != old->uid &&
		    euid != old->euid  && euid != old->suid)
			goto error;
		if (suid != (uid_t) -1 && suid != old->uid &&
		    suid != old->euid  && suid != old->suid)
			goto error;
	}

	if (ruid != (uid_t) -1) {
		new->uid = ruid;
		if (ruid != old->uid) {
			retval = set_user(new);
			if (retval < 0)
				goto error;
		}
	}
	if (euid != (uid_t) -1)
		new->euid = euid;
	if (suid != (uid_t) -1)
		new->suid = suid;
	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 *, ruid, uid_t __user *, euid, uid_t __user *, suid)
{
	const struct cred *cred = current_cred();
	int retval;

	if (!(retval   = put_user(cred->uid,  ruid)) &&
	    !(retval   = put_user(cred->euid, euid)))
		retval = put_user(cred->suid, suid);

	return retval;
}

/*
 * Same as above, but for rgid, egid, sgid.
 */
SYSCALL_DEFINE3(setresgid, gid_t, rgid, gid_t, egid, gid_t, sgid)
{
	const struct cred *old;
	struct cred *new;
	int retval;

	new = prepare_creds();
	if (!new)
		return -ENOMEM;
	old = current_cred();

	retval = security_task_setgid(rgid, egid, sgid, LSM_SETID_RES);
	if (retval)
		goto error;

	retval = -EPERM;
	if (!capable(CAP_SETGID)) {
		if (rgid != (gid_t) -1 && rgid != old->gid &&
		    rgid != old->egid  && rgid != old->sgid)
			goto error;
		if (egid != (gid_t) -1 && egid != old->gid &&
		    egid != old->egid  && egid != old->sgid)
			goto error;
		if (sgid != (gid_t) -1 && sgid != old->gid &&
		    sgid != old->egid  && sgid != old->sgid)
			goto error;
	}

	if (rgid != (gid_t) -1)
		new->gid = rgid;
	if (egid != (gid_t) -1)
		new->egid = egid;
	if (sgid != (gid_t) -1)
		new->sgid = sgid;
	new->fsgid = new->egid;

	return commit_creds(new);

error:
	abort_creds(new);
	return retval;
}

SYSCALL_DEFINE3(getresgid, gid_t __user *, rgid, gid_t __user *, egid, gid_t __user *, sgid)
{
	const struct cred *cred = current_cred();
	int retval;

	if (!(retval   = put_user(cred->gid,  rgid)) &&
	    !(retval   = put_user(cred->egid, egid)))
		retval = put_user(cred->sgid, sgid);

	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;

	new = prepare_creds();
	if (!new)
		return current_fsuid();
	old = current_cred();
	old_fsuid = old->fsuid;

	if (security_task_setuid(uid, (uid_t)-1, (uid_t)-1, LSM_SETID_FS) < 0)
		goto error;

	if (uid == old->uid  || uid == old->euid  ||
	    uid == old->suid || uid == old->fsuid ||
	    capable(CAP_SETUID)) {
		if (uid != old_fsuid) {
			new->fsuid = uid;
			if (security_task_fix_setuid(new, old, LSM_SETID_FS) == 0)
				goto change_okay;
		}
	}

error:
	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;

	new = prepare_creds();
	if (!new)
		return current_fsgid();
	old = current_cred();
	old_fsgid = old->fsgid;

	if (security_task_setgid(gid, (gid_t)-1, (gid_t)-1, LSM_SETID_FS))
		goto error;

	if (gid == old->gid  || gid == old->egid  ||
	    gid == old->sgid || gid == old->fsgid ||
	    capable(CAP_SETGID)) {
		if (gid != old_fsgid) {
			new->fsgid = gid;
			goto change_okay;
		}
	}

error:
	abort_creds(new);
	return old_fsgid;

change_okay:
	commit_creds(new);
	return old_fsgid;
}

void do_sys_times(struct tms *tms)
{
	cputime_t tgutime, tgstime, cutime, cstime;

	spin_lock_irq(&current->sighand->siglock);
	thread_group_times(current, &tgutime, &tgstime);
	cutime = current->signal->cutime;
	cstime = current->signal->cstime;
	spin_unlock_irq(&current->sighand->siglock);
	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
 *
 * Auch. Had to add the 'did_exec' flag to conform completely to POSIX.
 * LBT 04.03.94
 */
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;

	/* 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->did_exec)
			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) {