[mirror_ubuntu-artful-kernel.git] / arch / x86 / kernel / signal_32.c

/*
 *  Copyright (C) 1991, 1992  Linus Torvalds
 *
 *  1997-11-28  Modified for POSIX.1b signals by Richard Henderson
 *  2000-06-20  Pentium III FXSR, SSE support by Gareth Hughes
 */

#include <linux/sched.h>
#include <linux/mm.h>
#include <linux/smp.h>
#include <linux/kernel.h>
#include <linux/signal.h>
#include <linux/errno.h>
#include <linux/wait.h>
#include <linux/unistd.h>
#include <linux/stddef.h>
#include <linux/personality.h>
#include <linux/suspend.h>
#include <linux/ptrace.h>
#include <linux/elf.h>
#include <linux/binfmts.h>
#include <asm/processor.h>
#include <asm/ucontext.h>
#include <asm/uaccess.h>
#include <asm/i387.h>
#include "sigframe_32.h"

#define DEBUG_SIG 0

#define _BLOCKABLE (~(sigmask(SIGKILL) | sigmask(SIGSTOP)))

/*
 * Atomically swap in the new signal mask, and wait for a signal.
 */
asmlinkage int
sys_sigsuspend(int history0, int history1, old_sigset_t mask)
{
	mask &= _BLOCKABLE;
	spin_lock_irq(&current->sighand->siglock);
	current->saved_sigmask = current->blocked;
	siginitset(&current->blocked, mask);
	recalc_sigpending();
	spin_unlock_irq(&current->sighand->siglock);

	current->state = TASK_INTERRUPTIBLE;
	schedule();
	set_thread_flag(TIF_RESTORE_SIGMASK);
	return -ERESTARTNOHAND;
}

asmlinkage int 
sys_sigaction(int sig, const struct old_sigaction __user *act,
	      struct old_sigaction __user *oact)
{
	struct k_sigaction new_ka, old_ka;
	int ret;

	if (act) {
		old_sigset_t mask;
		if (!access_ok(VERIFY_READ, act, sizeof(*act)) ||
		    __get_user(new_ka.sa.sa_handler, &act->sa_handler) ||
		    __get_user(new_ka.sa.sa_restorer, &act->sa_restorer))
			return -EFAULT;
		__get_user(new_ka.sa.sa_flags, &act->sa_flags);
		__get_user(mask, &act->sa_mask);
		siginitset(&new_ka.sa.sa_mask, mask);
	}

	ret = do_sigaction(sig, act ? &new_ka : NULL, oact ? &old_ka : NULL);

	if (!ret && oact) {
		if (!access_ok(VERIFY_WRITE, oact, sizeof(*oact)) ||
		    __put_user(old_ka.sa.sa_handler, &oact->sa_handler) ||
		    __put_user(old_ka.sa.sa_restorer, &oact->sa_restorer))
			return -EFAULT;
		__put_user(old_ka.sa.sa_flags, &oact->sa_flags);
		__put_user(old_ka.sa.sa_mask.sig[0], &oact->sa_mask);
	}

	return ret;
}

asmlinkage int
sys_sigaltstack(unsigned long ebx)
{
	/* This is needed to make gcc realize it doesn't own the "struct pt_regs" */
	struct pt_regs *regs = (struct pt_regs *)&ebx;
	const stack_t __user *uss = (const stack_t __user *)ebx;
	stack_t __user *uoss = (stack_t __user *)regs->ecx;

	return do_sigaltstack(uss, uoss, regs->esp);
}


/*
 * Do a signal return; undo the signal stack.
 */

static int
restore_sigcontext(struct pt_regs *regs, struct sigcontext __user *sc, int *peax)
{
	unsigned int err = 0;

	/* Always make any pending restarted system calls return -EINTR */
	current_thread_info()->restart_block.fn = do_no_restart_syscall;

#define COPY(x)		err |= __get_user(regs->x, &sc->x)

#define COPY_SEG(seg)							\
	{ unsigned short tmp;						\
	  err |= __get_user(tmp, &sc->seg);				\
	  regs->x##seg = tmp; }

#define COPY_SEG_STRICT(seg)						\
	{ unsigned short tmp;						\
	  err |= __get_user(tmp, &sc->seg);				\
	  regs->x##seg = tmp|3; }

#define GET_SEG(seg)							\
	{ unsigned short tmp;						\
	  err |= __get_user(tmp, &sc->seg);				\
	  loadsegment(seg,tmp); }

#define	FIX_EFLAGS	(X86_EFLAGS_AC | X86_EFLAGS_RF |		 \
			 X86_EFLAGS_OF | X86_EFLAGS_DF |		 \
			 X86_EFLAGS_TF | X86_EFLAGS_SF | X86_EFLAGS_ZF | \
			 X86_EFLAGS_AF | X86_EFLAGS_PF | X86_EFLAGS_CF)

	GET_SEG(gs);
	COPY_SEG(fs);
	COPY_SEG(es);
	COPY_SEG(ds);
	COPY(edi);
	COPY(esi);
	COPY(ebp);
	COPY(esp);
	COPY(ebx);
	COPY(edx);
	COPY(ecx);
	COPY(eip);
	COPY_SEG_STRICT(cs);
	COPY_SEG_STRICT(ss);
	
	{
		unsigned int tmpflags;
		err |= __get_user(tmpflags, &sc->eflags);
		regs->eflags = (regs->eflags & ~FIX_EFLAGS) | (tmpflags & FIX_EFLAGS);
		regs->orig_eax = -1;		/* disable syscall checks */
	}

	{
		struct _fpstate __user * buf;
		err |= __get_user(buf, &sc->fpstate);
		if (buf) {
			if (!access_ok(VERIFY_READ, buf, sizeof(*buf)))
				goto badframe;
			err |= restore_i387(buf);
		} else {
			struct task_struct *me = current;
			if (used_math()) {
				clear_fpu(me);
				clear_used_math();
			}
		}
	}

	err |= __get_user(*peax, &sc->eax);
	return err;

badframe:
	return 1;
}

asmlinkage int sys_sigreturn(unsigned long __unused)
{
	struct pt_regs *regs = (struct pt_regs *) &__unused;
	struct sigframe __user *frame = (struct sigframe __user *)(regs->esp - 8);
	sigset_t set;
	int eax;

	if (!access_ok(VERIFY_READ, frame, sizeof(*frame)))
		goto badframe;
	if (__get_user(set.sig[0], &frame->sc.oldmask)
	    || (_NSIG_WORDS > 1
		&& __copy_from_user(&set.sig[1], &frame->extramask,
				    sizeof(frame->extramask))))
		goto badframe;

	sigdelsetmask(&set, ~_BLOCKABLE);
	spin_lock_irq(&current->sighand->siglock);
	current->blocked = set;
	recalc_sigpending();
	spin_unlock_irq(&current->sighand->siglock);
	
	if (restore_sigcontext(regs, &frame->sc, &eax))
		goto badframe;
	return eax;

badframe:
	if (show_unhandled_signals && printk_ratelimit())
		printk("%s%s[%d] bad frame in sigreturn frame:%p eip:%lx"
		       " esp:%lx oeax:%lx\n",
		    task_pid_nr(current) > 1 ? KERN_INFO : KERN_EMERG,
		    current->comm, task_pid_nr(current), frame, regs->eip,
		    regs->esp, regs->orig_eax);

	force_sig(SIGSEGV, current);
	return 0;
}	

asmlinkage int sys_rt_sigreturn(unsigned long __unused)
{
	struct pt_regs *regs = (struct pt_regs *) &__unused;
	struct rt_sigframe __user *frame = (struct rt_sigframe __user *)(regs->esp - 4);
	sigset_t set;
	int eax;

	if (!access_ok(VERIFY_READ, frame, sizeof(*frame)))
		goto badframe;
	if (__copy_from_user(&set, &frame->uc.uc_sigmask, sizeof(set)))
		goto badframe;

	sigdelsetmask(&set, ~_BLOCKABLE);
	spin_lock_irq(&current->sighand->siglock);
	current->blocked = set;
	recalc_sigpending();
	spin_unlock_irq(&current->sighand->siglock);
	
	if (restore_sigcontext(regs, &frame->uc.uc_mcontext, &eax))
		goto badframe;

	if (do_sigaltstack(&frame->uc.uc_stack, NULL, regs->esp) == -EFAULT)
		goto badframe;

	return eax;

badframe:
	force_sig(SIGSEGV, current);
	return 0;
}	

/*
 * Set up a signal frame.
 */

static int
setup_sigcontext(struct sigcontext __user *sc, struct _fpstate __user *fpstate,
		 struct pt_regs *regs, unsigned long mask)
{
	int tmp, err = 0;

	err |= __put_user(regs->xfs, (unsigned int __user *)&sc->fs);
	savesegment(gs, tmp);
	err |= __put_user(tmp, (unsigned int __user *)&sc->gs);

	err |= __put_user(regs->xes, (unsigned int __user *)&sc->es);
	err |= __put_user(regs->xds, (unsigned int __user *)&sc->ds);
	err |= __put_user(regs->edi, &sc->edi);
	err |= __put_user(regs->esi, &sc->esi);
	err |= __put_user(regs->ebp, &sc->ebp);
	err |= __put_user(regs->esp, &sc->esp);
	err |= __put_user(regs->ebx, &sc->ebx);
	err |= __put_user(regs->edx, &sc->edx);
	err |= __put_user(regs->ecx, &sc->ecx);
	err |= __put_user(regs->eax, &sc->eax);
	err |= __put_user(current->thread.trap_no, &sc->trapno);
	err |= __put_user(current->thread.error_code, &sc->err);
	err |= __put_user(regs->eip, &sc->eip);
	err |= __put_user(regs->xcs, (unsigned int __user *)&sc->cs);
	err |= __put_user(regs->eflags, &sc->eflags);
	err |= __put_user(regs->esp, &sc->esp_at_signal);
	err |= __put_user(regs->xss, (unsigned int __user *)&sc->ss);

	tmp = save_i387(fpstate);
	if (tmp < 0)
	  err = 1;
	else
	  err |= __put_user(tmp ? fpstate : NULL, &sc->fpstate);

	/* non-iBCS2 extensions.. */
	err |= __put_user(mask, &sc->oldmask);
	err |= __put_user(current->thread.cr2, &sc->cr2);

	return err;
}

/*
 * Determine which stack to use..
 */
static inline void __user *
get_sigframe(struct k_sigaction *ka, struct pt_regs * regs, size_t frame_size)
{
	unsigned long esp;

	/* Default to using normal stack */
	esp = regs->esp;

	/* This is the X/Open sanctioned signal stack switching.  */
	if (ka->sa.sa_flags & SA_ONSTACK) {
		if (sas_ss_flags(esp) == 0)
			esp = current->sas_ss_sp + current->sas_ss_size;
	}

	/* This is the legacy signal stack switching. */
	else if ((regs->xss & 0xffff) != __USER_DS &&
		 !(ka->sa.sa_flags & SA_RESTORER) &&
		 ka->sa.sa_restorer) {
		esp = (unsigned long) ka->sa.sa_restorer;
	}

	esp -= frame_size;
	/* Align the stack pointer according to the i386 ABI,
	 * i.e. so that on function entry ((sp + 4) & 15) == 0. */
	esp = ((esp + 4) & -16ul) - 4;
	return (void __user *) esp;
}

/* These symbols are defined with the addresses in the vsyscall page.
   See vsyscall-sigreturn.S.  */
extern void __user __kernel_sigreturn;
extern void __user __kernel_rt_sigreturn;

static int setup_frame(int sig, struct k_sigaction *ka,
		       sigset_t *set, struct pt_regs * regs)
{
	void __user *restorer;
	struct sigframe __user *frame;
	int err = 0;
	int usig;

	frame = get_sigframe(ka, regs, sizeof(*frame));

	if (!access_ok(VERIFY_WRITE, frame, sizeof(*frame)))
		goto give_sigsegv;

	usig = current_thread_info()->exec_domain
		&& current_thread_info()->exec_domain->signal_invmap
		&& sig < 32
		? current_thread_info()->exec_domain->signal_invmap[sig]
		: sig;

	err = __put_user(usig, &frame->sig);
	if (err)
		goto give_sigsegv;

	err = setup_sigcontext(&frame->sc, &frame->fpstate, regs, set->sig[0]);
	if (err)
		goto give_sigsegv;

	if (_NSIG_WORDS > 1) {
		err = __copy_to_user(&frame->extramask, &set->sig[1],
				      sizeof(frame->extramask));
		if (err)
			goto give_sigsegv;
	}

	if (current->binfmt->hasvdso)
		restorer = (void *)VDSO_SYM(&__kernel_sigreturn);
	else
		restorer = (void *)&frame->retcode;
	if (ka->sa.sa_flags & SA_RESTORER)
		restorer = ka->sa.sa_restorer;

	/* Set up to return from userspace.  */
	err |= __put_user(restorer, &frame->pretcode);
	 
	/*
	 * This is popl %eax ; movl $,%eax ; int $0x80
	 *
	 * WE DO NOT USE IT ANY MORE! It's only left here for historical
	 * reasons and because gdb uses it as a signature to notice
	 * signal handler stack frames.
	 */
	err |= __put_user(0xb858, (short __user *)(frame->retcode+0));
	err |= __put_user(__NR_sigreturn, (int __user *)(frame->retcode+2));
	err |= __put_user(0x80cd, (short __user *)(frame->retcode+6));

	if (err)
		goto give_sigsegv;

	/* Set up registers for signal handler */
	regs->esp = (unsigned long) frame;
	regs->eip = (unsigned long) ka->sa.sa_handler;
	regs->eax = (unsigned long) sig;
	regs->edx = (unsigned long) 0;
	regs->ecx = (unsigned long) 0;

	regs->xds = __USER_DS;
	regs->xes = __USER_DS;
	regs->xss = __USER_DS;
	regs->xcs = __USER_CS;

	/*
	 * Clear TF when entering the signal handler, but
	 * notify any tracer that was single-stepping it.
	 * The tracer may want to single-step inside the
	 * handler too.
	 */
	regs->eflags &= ~TF_MASK;
	if (test_thread_flag(TIF_SINGLESTEP))
		ptrace_notify(SIGTRAP);

#if DEBUG_SIG
	printk("SIG deliver (%s:%d): sp=%p pc=%p ra=%p\n",
		current->comm, current->pid, frame, regs->eip, frame->pretcode);
#endif

	return 0;

give_sigsegv:
	force_sigsegv(sig, current);
	return -EFAULT;
}

static int setup_rt_frame(int sig, struct k_sigaction *ka, siginfo_t *info,
			   sigset_t *set, struct pt_regs * regs)
{
	void __user *restorer;
	struct rt_sigframe __user *frame;
	int err = 0;
	int usig;

	frame = get_sigframe(ka, regs, sizeof(*frame));

	if (!access_ok(VERIFY_WRITE, frame, sizeof(*frame)))
		goto give_sigsegv;

	usig = current_thread_info()->exec_domain
		&& current_thread_info()->exec_domain->signal_invmap
		&& sig < 32
		? current_thread_info()->exec_domain->signal_invmap[sig]
		: sig;

	err |= __put_user(usig, &frame->sig);
	err |= __put_user(&frame->info, &frame->pinfo);
	err |= __put_user(&frame->uc, &frame->puc);
	err |= copy_siginfo_to_user(&frame->info, info);
	if (err)
		goto give_sigsegv;

	/* Create the ucontext.  */
	err |= __put_user(0, &frame->uc.uc_flags);
	err |= __put_user(0, &frame->uc.uc_link);
	err |= __put_user(current->sas_ss_sp, &frame->uc.uc_stack.ss_sp);
	err |= __put_user(sas_ss_flags(regs->esp),
			  &frame->uc.uc_stack.ss_flags);
	err |= __put_user(current->sas_ss_size, &frame->uc.uc_stack.ss_size);
	err |= setup_sigcontext(&frame->uc.uc_mcontext, &frame->fpstate,
			        regs, set->sig[0]);
	err |= __copy_to_user(&frame->uc.uc_sigmask, set, sizeof(*set));
	if (err)
		goto give_sigsegv;

	/* Set up to return from userspace.  */
	restorer = (void *)VDSO_SYM(&__kernel_rt_sigreturn);
	if (ka->sa.sa_flags & SA_RESTORER)
		restorer = ka->sa.sa_restorer;
	err |= __put_user(restorer, &frame->pretcode);
	 
	/*
	 * This is movl $,%eax ; int $0x80
	 *
	 * WE DO NOT USE IT ANY MORE! It's only left here for historical
	 * reasons and because gdb uses it as a signature to notice
	 * signal handler stack frames.
	 */
	err |= __put_user(0xb8, (char __user *)(frame->retcode+0));
	err |= __put_user(__NR_rt_sigreturn, (int __user *)(frame->retcode+1));
	err |= __put_user(0x80cd, (short __user *)(frame->retcode+5));

	if (err)
		goto give_sigsegv;

	/* Set up registers for signal handler */
	regs->esp = (unsigned long) frame;
	regs->eip = (unsigned long) ka->sa.sa_handler;
	regs->eax = (unsigned long) usig;
	regs->edx = (unsigned long) &frame->info;
	regs->ecx = (unsigned long) &frame->uc;

	regs->xds = __USER_DS;
	regs->xes = __USER_DS;
	regs->xss = __USER_DS;
	regs->xcs = __USER_CS;

	/*
	 * Clear TF when entering the signal handler, but
	 * notify any tracer that was single-stepping it.
	 * The tracer may want to single-step inside the
	 * handler too.
	 */
	regs->eflags &= ~TF_MASK;
	if (test_thread_flag(TIF_SINGLESTEP))
		ptrace_notify(SIGTRAP);

#if DEBUG_SIG
	printk("SIG deliver (%s:%d): sp=%p pc=%p ra=%p\n",
		current->comm, current->pid, frame, regs->eip, frame->pretcode);
#endif

	return 0;

give_sigsegv:
	force_sigsegv(sig, current);
	return -EFAULT;
}

/*
 * OK, we're invoking a handler
 */	

static int
handle_signal(unsigned long sig, siginfo_t *info, struct k_sigaction *ka,
	      sigset_t *oldset,	struct pt_regs * regs)
{
	int ret;

	/* Are we from a system call? */
	if (regs->orig_eax >= 0) {
		/* If so, check system call restarting.. */
		switch (regs->eax) {
		        case -ERESTART_RESTARTBLOCK:
			case -ERESTARTNOHAND:
				regs->eax = -EINTR;
				break;

			case -ERESTARTSYS:
				if (!(ka->sa.sa_flags & SA_RESTART)) {
					regs->eax = -EINTR;
					break;
				}
			/* fallthrough */
			case -ERESTARTNOINTR:
				regs->eax = regs->orig_eax;
				regs->eip -= 2;
		}
	}

	/*
	 * If TF is set due to a debugger (PT_DTRACE), clear the TF flag so
	 * that register information in the sigcontext is correct.
	 */
	if (unlikely(regs->eflags & TF_MASK)
	    && likely(current->ptrace & PT_DTRACE)) {
		current->ptrace &= ~PT_DTRACE;
		regs->eflags &= ~TF_MASK;
	}

	/* Set up the stack frame */
	if (ka->sa.sa_flags & SA_SIGINFO)
		ret = setup_rt_frame(sig, ka, info, oldset, regs);
	else
		ret = setup_frame(sig, ka, oldset, regs);

	if (ret == 0) {
		spin_lock_irq(&current->sighand->siglock);
		sigorsets(&current->blocked,&current->blocked,&ka->sa.sa_mask);
		if (!(ka->sa.sa_flags & SA_NODEFER))
			sigaddset(&current->blocked,sig);
		recalc_sigpending();
		spin_unlock_irq(&current->sighand->siglock);
	}

	return ret;
}

/*
 * Note that 'init' is a special process: it doesn't get signals it doesn't
 * want to handle. Thus you cannot kill init even with a SIGKILL even by
 * mistake.
 */
static void fastcall do_signal(struct pt_regs *regs)
{
	siginfo_t info;
	int signr;
	struct k_sigaction ka;
	sigset_t *oldset;

	/*
	 * We want the common case to go fast, which
	 * is why we may in certain cases get here from
	 * kernel mode. Just return without doing anything
 	 * if so.  vm86 regs switched out by assembly code
 	 * before reaching here, so testing against kernel
 	 * CS suffices.
	 */
	if (!user_mode(regs))
		return;

	if (test_thread_flag(TIF_RESTORE_SIGMASK))
		oldset = &current->saved_sigmask;
	else
		oldset = &current->blocked;

	signr = get_signal_to_deliver(&info, &ka, regs, NULL);
	if (signr > 0) {
		/* Re-enable any watchpoints before delivering the
		 * signal to user space. The processor register will
		 * have been cleared if the watchpoint triggered
		 * inside the kernel.
		 */
		if (unlikely(current->thread.debugreg[7]))
			set_debugreg(current->thread.debugreg[7], 7);

		/* Whee!  Actually deliver the signal.  */
		if (handle_signal(signr, &info, &ka, oldset, regs) == 0) {
			/* a signal was successfully delivered; the saved
			 * sigmask will have been stored in the signal frame,
			 * and will be restored by sigreturn, so we can simply
			 * clear the TIF_RESTORE_SIGMASK flag */
			if (test_thread_flag(TIF_RESTORE_SIGMASK))
				clear_thread_flag(TIF_RESTORE_SIGMASK);
		}

		return;
	}

	/* Did we come from a system call? */
	if (regs->orig_eax >= 0) {
		/* Restart the system call - no handlers present */
		switch (regs->eax) {
		case -ERESTARTNOHAND:
		case -ERESTARTSYS:
		case -ERESTARTNOINTR:
			regs->eax = regs->orig_eax;
			regs->eip -= 2;
			break;

		case -ERESTART_RESTARTBLOCK:
			regs->eax = __NR_restart_syscall;
			regs->eip -= 2;
			break;
		}
	}

	/* if there's no signal to deliver, we just put the saved sigmask
	 * back */
	if (test_thread_flag(TIF_RESTORE_SIGMASK)) {
		clear_thread_flag(TIF_RESTORE_SIGMASK);
		sigprocmask(SIG_SETMASK, &current->saved_sigmask, NULL);
	}
}

/*
 * notification of userspace execution resumption
 * - triggered by the TIF_WORK_MASK flags
 */
__attribute__((regparm(3)))
void do_notify_resume(struct pt_regs *regs, void *_unused,
		      __u32 thread_info_flags)
{
	/* Pending single-step? */
	if (thread_info_flags & _TIF_SINGLESTEP) {
		regs->eflags |= TF_MASK;
		clear_thread_flag(TIF_SINGLESTEP);
	}

	/* deal with pending signal delivery */
	if (thread_info_flags & (_TIF_SIGPENDING | _TIF_RESTORE_SIGMASK))
		do_signal(regs);
	
	clear_thread_flag(TIF_IRET);
}
Commit	Line	Data
1da177e4	1	/*
1da177e4 LT	2	* Copyright (C) 1991, 1992 Linus Torvalds
	3	*
	4	* 1997-11-28 Modified for POSIX.1b signals by Richard Henderson
	5	* 2000-06-20 Pentium III FXSR, SSE support by Gareth Hughes
	6	*/
	7
	8	#include <linux/sched.h>
	9	#include <linux/mm.h>
	10	#include <linux/smp.h>
1da177e4 LT	11	#include <linux/kernel.h>
	12	#include <linux/signal.h>
	13	#include <linux/errno.h>
	14	#include <linux/wait.h>
	15	#include <linux/unistd.h>
	16	#include <linux/stddef.h>
	17	#include <linux/personality.h>
	18	#include <linux/suspend.h>
	19	#include <linux/ptrace.h>
	20	#include <linux/elf.h>
9fbbd4dd	21	#include <linux/binfmts.h>
1da177e4 LT	22	#include <asm/processor.h>
	23	#include <asm/ucontext.h>
	24	#include <asm/uaccess.h>
	25	#include <asm/i387.h>
56cc623c	26	#include "sigframe_32.h"
1da177e4 LT	27
	28	#define DEBUG_SIG 0
	29
	30	#define _BLOCKABLE (~(sigmask(SIGKILL) \| sigmask(SIGSTOP)))
	31
	32	/*
	33	* Atomically swap in the new signal mask, and wait for a signal.
	34	*/
	35	asmlinkage int
	36	sys_sigsuspend(int history0, int history1, old_sigset_t mask)
	37	{
1da177e4 LT	38	mask &= _BLOCKABLE;
1da177e4 LT	39	spin_lock_irq(&current->sighand->siglock);
283828f3	40	current->saved_sigmask = current->blocked;
1da177e4 LT	41	siginitset(&current->blocked, mask);
	42	recalc_sigpending();
	43	spin_unlock_irq(&current->sighand->siglock);
	44
283828f3 DH	45	current->state = TASK_INTERRUPTIBLE;
	46	schedule();
	47	set_thread_flag(TIF_RESTORE_SIGMASK);
	48	return -ERESTARTNOHAND;
1da177e4 LT	49	}
	50
	51	asmlinkage int
	52	sys_sigaction(int sig, const struct old_sigaction __user *act,
	53	struct old_sigaction __user *oact)
	54	{
	55	struct k_sigaction new_ka, old_ka;
	56	int ret;
	57
	58	if (act) {
	59	old_sigset_t mask;
	60	if (!access_ok(VERIFY_READ, act, sizeof(*act)) \|\|
	61	__get_user(new_ka.sa.sa_handler, &act->sa_handler) \|\|
	62	__get_user(new_ka.sa.sa_restorer, &act->sa_restorer))
	63	return -EFAULT;
	64	__get_user(new_ka.sa.sa_flags, &act->sa_flags);
	65	__get_user(mask, &act->sa_mask);
	66	siginitset(&new_ka.sa.sa_mask, mask);
	67	}
	68
	69	ret = do_sigaction(sig, act ? &new_ka : NULL, oact ? &old_ka : NULL);
	70
	71	if (!ret && oact) {
	72	if (!access_ok(VERIFY_WRITE, oact, sizeof(*oact)) \|\|
	73	__put_user(old_ka.sa.sa_handler, &oact->sa_handler) \|\|
	74	__put_user(old_ka.sa.sa_restorer, &oact->sa_restorer))
	75	return -EFAULT;
	76	__put_user(old_ka.sa.sa_flags, &oact->sa_flags);
	77	__put_user(old_ka.sa.sa_mask.sig[0], &oact->sa_mask);
	78	}
	79
	80	return ret;
	81	}
	82
	83	asmlinkage int
	84	sys_sigaltstack(unsigned long ebx)
	85	{
	86	/* This is needed to make gcc realize it doesn't own the "struct pt_regs" */
	87	struct pt_regs regs = (struct pt_regs )&ebx;
	88	const stack_t __user uss = (const stack_t __user )ebx;
	89	stack_t __user uoss = (stack_t __user )regs->ecx;
	90
	91	return do_sigaltstack(uss, uoss, regs->esp);
	92	}
	93
	94
	95	/*
	96	* Do a signal return; undo the signal stack.
	97	*/
	98
	99	static int
	100	restore_sigcontext(struct pt_regs regs, struct sigcontext __user sc, int *peax)
	101	{
	102	unsigned int err = 0;
	103
	104	/* Always make any pending restarted system calls return -EINTR */
	105	current_thread_info()->restart_block.fn = do_no_restart_syscall;
	106
	107	#define COPY(x) err \|= __get_user(regs->x, &sc->x)
	108
	109	#define COPY_SEG(seg) \
	110	{ unsigned short tmp; \
	111	err \|= __get_user(tmp, &sc->seg); \
	112	regs->x##seg = tmp; }
113
114	#define COPY_SEG_STRICT(seg) \
115	{ unsigned short tmp; \
116	err \|= __get_user(tmp, &sc->seg); \
117	regs->x##seg = tmp\|3; }
118
119	#define GET_SEG(seg) \
120	{ unsigned short tmp; \
121	err \|= __get_user(tmp, &sc->seg); \
122	loadsegment(seg,tmp); }
123
8bed51cd CE	124	#define FIX_EFLAGS (X86_EFLAGS_AC \| X86_EFLAGS_RF \| \
8bed51cd CE	125	X86_EFLAGS_OF \| X86_EFLAGS_DF \| \
1da177e4 LT	126	X86_EFLAGS_TF \| X86_EFLAGS_SF \| X86_EFLAGS_ZF \| \
	127	X86_EFLAGS_AF \| X86_EFLAGS_PF \| X86_EFLAGS_CF)
	128
464d1a78 JF	129	GET_SEG(gs);
464d1a78 JF	130	COPY_SEG(fs);
1da177e4 LT	131	COPY_SEG(es);
	132	COPY_SEG(ds);
	133	COPY(edi);
	134	COPY(esi);
	135	COPY(ebp);
	136	COPY(esp);
	137	COPY(ebx);
	138	COPY(edx);
	139	COPY(ecx);
	140	COPY(eip);
	141	COPY_SEG_STRICT(cs);
	142	COPY_SEG_STRICT(ss);
	143
	144	{
	145	unsigned int tmpflags;
	146	err \|= __get_user(tmpflags, &sc->eflags);
	147	regs->eflags = (regs->eflags & ~FIX_EFLAGS) \| (tmpflags & FIX_EFLAGS);
	148	regs->orig_eax = -1; /* disable syscall checks */
	149	}
	150
	151	{
	152	struct _fpstate __user * buf;
	153	err \|= __get_user(buf, &sc->fpstate);
	154	if (buf) {
	155	if (!access_ok(VERIFY_READ, buf, sizeof(*buf)))
	156	goto badframe;
	157	err \|= restore_i387(buf);
	158	} else {
	159	struct task_struct *me = current;
	160	if (used_math()) {
	161	clear_fpu(me);
	162	clear_used_math();
	163	}
	164	}
	165	}
	166
	167	err \|= __get_user(*peax, &sc->eax);
	168	return err;
	169
	170	badframe:
	171	return 1;
	172	}
	173
	174	asmlinkage int sys_sigreturn(unsigned long __unused)
	175	{
	176	struct pt_regs regs = (struct pt_regs ) &__unused;
	177	struct sigframe __user frame = (struct sigframe __user )(regs->esp - 8);
	178	sigset_t set;
	179	int eax;
	180
	181	if (!access_ok(VERIFY_READ, frame, sizeof(*frame)))
	182	goto badframe;
	183	if (__get_user(set.sig[0], &frame->sc.oldmask)
	184	\|\| (_NSIG_WORDS > 1
	185	&& __copy_from_user(&set.sig[1], &frame->extramask,
	186	sizeof(frame->extramask))))
	187	goto badframe;
	188
	189	sigdelsetmask(&set, ~_BLOCKABLE);
	190	spin_lock_irq(&current->sighand->siglock);
	191	current->blocked = set;
	192	recalc_sigpending();
	193	spin_unlock_irq(&current->sighand->siglock);
	194
195	if (restore_sigcontext(regs, &frame->sc, &eax))
196	goto badframe;
197	return eax;
198
199	badframe:
abd4f750 MAS	200	if (show_unhandled_signals && printk_ratelimit())
	201	printk("%s%s[%d] bad frame in sigreturn frame:%p eip:%lx"
	202	" esp:%lx oeax:%lx\n",
19c5870c AD	203	task_pid_nr(current) > 1 ? KERN_INFO : KERN_EMERG,
19c5870c AD	204	current->comm, task_pid_nr(current), frame, regs->eip,
abd4f750 MAS	205	regs->esp, regs->orig_eax);
abd4f750 MAS	206
1da177e4 LT	207	force_sig(SIGSEGV, current);
	208	return 0;
	209	}
	210
	211	asmlinkage int sys_rt_sigreturn(unsigned long __unused)
	212	{
	213	struct pt_regs regs = (struct pt_regs ) &__unused;
	214	struct rt_sigframe __user frame = (struct rt_sigframe __user )(regs->esp - 4);
	215	sigset_t set;
	216	int eax;
	217
	218	if (!access_ok(VERIFY_READ, frame, sizeof(*frame)))
	219	goto badframe;
	220	if (__copy_from_user(&set, &frame->uc.uc_sigmask, sizeof(set)))
	221	goto badframe;
	222
	223	sigdelsetmask(&set, ~_BLOCKABLE);
	224	spin_lock_irq(&current->sighand->siglock);
	225	current->blocked = set;
	226	recalc_sigpending();
	227	spin_unlock_irq(&current->sighand->siglock);
	228
	229	if (restore_sigcontext(regs, &frame->uc.uc_mcontext, &eax))
	230	goto badframe;
	231
	232	if (do_sigaltstack(&frame->uc.uc_stack, NULL, regs->esp) == -EFAULT)
	233	goto badframe;
	234
	235	return eax;
	236
	237	badframe:
	238	force_sig(SIGSEGV, current);
	239	return 0;
	240	}
	241
	242	/*
	243	* Set up a signal frame.
	244	*/
	245
	246	static int
	247	setup_sigcontext(struct sigcontext __user sc, struct _fpstate __user fpstate,
	248	struct pt_regs *regs, unsigned long mask)
	249	{
	250	int tmp, err = 0;
	251
464d1a78 JF	252	err \|= __put_user(regs->xfs, (unsigned int __user *)&sc->fs);
	253	savesegment(gs, tmp);
	254	err \|= __put_user(tmp, (unsigned int __user *)&sc->gs);
1da177e4 LT	255
	256	err \|= __put_user(regs->xes, (unsigned int __user *)&sc->es);
	257	err \|= __put_user(regs->xds, (unsigned int __user *)&sc->ds);
	258	err \|= __put_user(regs->edi, &sc->edi);
	259	err \|= __put_user(regs->esi, &sc->esi);
	260	err \|= __put_user(regs->ebp, &sc->ebp);
	261	err \|= __put_user(regs->esp, &sc->esp);
	262	err \|= __put_user(regs->ebx, &sc->ebx);
	263	err \|= __put_user(regs->edx, &sc->edx);
	264	err \|= __put_user(regs->ecx, &sc->ecx);
	265	err \|= __put_user(regs->eax, &sc->eax);
	266	err \|= __put_user(current->thread.trap_no, &sc->trapno);
	267	err \|= __put_user(current->thread.error_code, &sc->err);
	268	err \|= __put_user(regs->eip, &sc->eip);
	269	err \|= __put_user(regs->xcs, (unsigned int __user *)&sc->cs);
	270	err \|= __put_user(regs->eflags, &sc->eflags);
	271	err \|= __put_user(regs->esp, &sc->esp_at_signal);
	272	err \|= __put_user(regs->xss, (unsigned int __user *)&sc->ss);
	273
	274	tmp = save_i387(fpstate);
	275	if (tmp < 0)
	276	err = 1;
	277	else
	278	err \|= __put_user(tmp ? fpstate : NULL, &sc->fpstate);
	279
	280	/* non-iBCS2 extensions.. */
	281	err \|= __put_user(mask, &sc->oldmask);
	282	err \|= __put_user(current->thread.cr2, &sc->cr2);
	283
	284	return err;
	285	}
	286
	287	/*
	288	* Determine which stack to use..
	289	*/
	290	static inline void __user *
	291	get_sigframe(struct k_sigaction ka, struct pt_regs regs, size_t frame_size)
	292	{
	293	unsigned long esp;
	294
	295	/* Default to using normal stack */
	296	esp = regs->esp;
	297
	298	/* This is the X/Open sanctioned signal stack switching. */
	299	if (ka->sa.sa_flags & SA_ONSTACK) {
	300	if (sas_ss_flags(esp) == 0)
	301	esp = current->sas_ss_sp + current->sas_ss_size;
	302	}
	303
	304	/* This is the legacy signal stack switching. */
	305	else if ((regs->xss & 0xffff) != __USER_DS &&
	306	!(ka->sa.sa_flags & SA_RESTORER) &&
	307	ka->sa.sa_restorer) {
	308	esp = (unsigned long) ka->sa.sa_restorer;
	309	}
	310
d347f372 MO	311	esp -= frame_size;
	312	/* Align the stack pointer according to the i386 ABI,
	313	* i.e. so that on function entry ((sp + 4) & 15) == 0. */
	314	esp = ((esp + 4) & -16ul) - 4;
	315	return (void __user *) esp;
1da177e4 LT	316	}
	317
	318	/* These symbols are defined with the addresses in the vsyscall page.
	319	See vsyscall-sigreturn.S. */
	320	extern void __user __kernel_sigreturn;
	321	extern void __user __kernel_rt_sigreturn;
	322
7c1def16 RM	323	static int setup_frame(int sig, struct k_sigaction *ka,
7c1def16 RM	324	sigset_t set, struct pt_regs regs)
1da177e4 LT	325	{
	326	void __user *restorer;
	327	struct sigframe __user *frame;
	328	int err = 0;
	329	int usig;
	330
	331	frame = get_sigframe(ka, regs, sizeof(*frame));
	332
	333	if (!access_ok(VERIFY_WRITE, frame, sizeof(*frame)))
	334	goto give_sigsegv;
	335
	336	usig = current_thread_info()->exec_domain
	337	&& current_thread_info()->exec_domain->signal_invmap
	338	&& sig < 32
	339	? current_thread_info()->exec_domain->signal_invmap[sig]
	340	: sig;
	341
	342	err = __put_user(usig, &frame->sig);
	343	if (err)
	344	goto give_sigsegv;
	345
	346	err = setup_sigcontext(&frame->sc, &frame->fpstate, regs, set->sig[0]);
	347	if (err)
	348	goto give_sigsegv;
	349
	350	if (_NSIG_WORDS > 1) {
	351	err = __copy_to_user(&frame->extramask, &set->sig[1],
	352	sizeof(frame->extramask));
	353	if (err)
	354	goto give_sigsegv;
	355	}
	356
9fbbd4dd AK	357	if (current->binfmt->hasvdso)
	358	restorer = (void *)VDSO_SYM(&__kernel_sigreturn);
	359	else
	360	restorer = (void *)&frame->retcode;
1da177e4 LT	361	if (ka->sa.sa_flags & SA_RESTORER)
	362	restorer = ka->sa.sa_restorer;
	363
	364	/* Set up to return from userspace. */
	365	err \|= __put_user(restorer, &frame->pretcode);
	366
	367	/*
	368	* This is popl %eax ; movl $,%eax ; int $0x80
	369	*
	370	* WE DO NOT USE IT ANY MORE! It's only left here for historical
	371	* reasons and because gdb uses it as a signature to notice
	372	* signal handler stack frames.
	373	*/
	374	err \|= __put_user(0xb858, (short __user *)(frame->retcode+0));
	375	err \|= __put_user(__NR_sigreturn, (int __user *)(frame->retcode+2));
	376	err \|= __put_user(0x80cd, (short __user *)(frame->retcode+6));
	377
	378	if (err)
	379	goto give_sigsegv;
	380
	381	/* Set up registers for signal handler */
	382	regs->esp = (unsigned long) frame;
	383	regs->eip = (unsigned long) ka->sa.sa_handler;
	384	regs->eax = (unsigned long) sig;
	385	regs->edx = (unsigned long) 0;
	386	regs->ecx = (unsigned long) 0;
	387
1da177e4 LT	388	regs->xds = __USER_DS;
	389	regs->xes = __USER_DS;
	390	regs->xss = __USER_DS;
	391	regs->xcs = __USER_CS;
	392
	393	/*
	394	* Clear TF when entering the signal handler, but
	395	* notify any tracer that was single-stepping it.
	396	* The tracer may want to single-step inside the
	397	* handler too.
	398	*/
	399	regs->eflags &= ~TF_MASK;
	400	if (test_thread_flag(TIF_SINGLESTEP))
	401	ptrace_notify(SIGTRAP);
	402
	403	#if DEBUG_SIG
	404	printk("SIG deliver (%s:%d): sp=%p pc=%p ra=%p\n",
	405	current->comm, current->pid, frame, regs->eip, frame->pretcode);
	406	#endif
	407
283828f3	408	return 0;
1da177e4 LT	409
	410	give_sigsegv:
	411	force_sigsegv(sig, current);
283828f3	412	return -EFAULT;
1da177e4 LT	413	}
1da177e4 LT	414
7c1def16	415	static int setup_rt_frame(int sig, struct k_sigaction ka, siginfo_t info,
1da177e4 LT	416	sigset_t set, struct pt_regs regs)
	417	{
	418	void __user *restorer;
	419	struct rt_sigframe __user *frame;
	420	int err = 0;
	421	int usig;
	422
	423	frame = get_sigframe(ka, regs, sizeof(*frame));
	424
	425	if (!access_ok(VERIFY_WRITE, frame, sizeof(*frame)))
	426	goto give_sigsegv;
	427
	428	usig = current_thread_info()->exec_domain
	429	&& current_thread_info()->exec_domain->signal_invmap
	430	&& sig < 32
	431	? current_thread_info()->exec_domain->signal_invmap[sig]
	432	: sig;
	433
	434	err \|= __put_user(usig, &frame->sig);
	435	err \|= __put_user(&frame->info, &frame->pinfo);
	436	err \|= __put_user(&frame->uc, &frame->puc);
	437	err \|= copy_siginfo_to_user(&frame->info, info);
	438	if (err)
	439	goto give_sigsegv;
	440
	441	/* Create the ucontext. */
	442	err \|= __put_user(0, &frame->uc.uc_flags);
	443	err \|= __put_user(0, &frame->uc.uc_link);
	444	err \|= __put_user(current->sas_ss_sp, &frame->uc.uc_stack.ss_sp);
	445	err \|= __put_user(sas_ss_flags(regs->esp),
	446	&frame->uc.uc_stack.ss_flags);
	447	err \|= __put_user(current->sas_ss_size, &frame->uc.uc_stack.ss_size);
	448	err \|= setup_sigcontext(&frame->uc.uc_mcontext, &frame->fpstate,
	449	regs, set->sig[0]);
	450	err \|= __copy_to_user(&frame->uc.uc_sigmask, set, sizeof(*set));
	451	if (err)
	452	goto give_sigsegv;
	453
	454	/* Set up to return from userspace. */
e6e5494c	455	restorer = (void *)VDSO_SYM(&__kernel_rt_sigreturn);
1da177e4 LT	456	if (ka->sa.sa_flags & SA_RESTORER)
	457	restorer = ka->sa.sa_restorer;
	458	err \|= __put_user(restorer, &frame->pretcode);
	459
	460	/*
	461	* This is movl $,%eax ; int $0x80
	462	*
	463	* WE DO NOT USE IT ANY MORE! It's only left here for historical
	464	* reasons and because gdb uses it as a signature to notice
	465	* signal handler stack frames.
	466	*/
	467	err \|= __put_user(0xb8, (char __user *)(frame->retcode+0));
	468	err \|= __put_user(__NR_rt_sigreturn, (int __user *)(frame->retcode+1));
	469	err \|= __put_user(0x80cd, (short __user *)(frame->retcode+5));
	470
	471	if (err)
	472	goto give_sigsegv;
	473
	474	/* Set up registers for signal handler */
	475	regs->esp = (unsigned long) frame;
	476	regs->eip = (unsigned long) ka->sa.sa_handler;
	477	regs->eax = (unsigned long) usig;
	478	regs->edx = (unsigned long) &frame->info;
	479	regs->ecx = (unsigned long) &frame->uc;
	480
1da177e4 LT	481	regs->xds = __USER_DS;
	482	regs->xes = __USER_DS;
	483	regs->xss = __USER_DS;
	484	regs->xcs = __USER_CS;
	485
	486	/*
	487	* Clear TF when entering the signal handler, but
	488	* notify any tracer that was single-stepping it.
	489	* The tracer may want to single-step inside the
	490	* handler too.
	491	*/
	492	regs->eflags &= ~TF_MASK;
	493	if (test_thread_flag(TIF_SINGLESTEP))
	494	ptrace_notify(SIGTRAP);
	495
	496	#if DEBUG_SIG
	497	printk("SIG deliver (%s:%d): sp=%p pc=%p ra=%p\n",
	498	current->comm, current->pid, frame, regs->eip, frame->pretcode);
	499	#endif
	500
283828f3	501	return 0;
1da177e4 LT	502
	503	give_sigsegv:
	504	force_sigsegv(sig, current);
283828f3	505	return -EFAULT;
1da177e4 LT	506	}
	507
	508	/*
	509	* OK, we're invoking a handler
	510	*/
	511
7c1def16	512	static int
1da177e4 LT	513	handle_signal(unsigned long sig, siginfo_t info, struct k_sigaction ka,
	514	sigset_t oldset, struct pt_regs regs)
	515	{
7c1def16 RM	516	int ret;
7c1def16 RM	517
1da177e4 LT	518	/* Are we from a system call? */
	519	if (regs->orig_eax >= 0) {
	520	/* If so, check system call restarting.. */
	521	switch (regs->eax) {
	522	case -ERESTART_RESTARTBLOCK:
	523	case -ERESTARTNOHAND:
	524	regs->eax = -EINTR;
	525	break;
	526
	527	case -ERESTARTSYS:
	528	if (!(ka->sa.sa_flags & SA_RESTART)) {
	529	regs->eax = -EINTR;
	530	break;
	531	}
	532	/* fallthrough */
	533	case -ERESTARTNOINTR:
	534	regs->eax = regs->orig_eax;
	535	regs->eip -= 2;
	536	}
	537	}
	538
	539	/*
	540	* If TF is set due to a debugger (PT_DTRACE), clear the TF flag so
	541	* that register information in the sigcontext is correct.
	542	*/
	543	if (unlikely(regs->eflags & TF_MASK)
	544	&& likely(current->ptrace & PT_DTRACE)) {
	545	current->ptrace &= ~PT_DTRACE;
	546	regs->eflags &= ~TF_MASK;
	547	}
	548
	549	/* Set up the stack frame */
	550	if (ka->sa.sa_flags & SA_SIGINFO)
7c1def16	551	ret = setup_rt_frame(sig, ka, info, oldset, regs);
1da177e4	552	else
7c1def16	553	ret = setup_frame(sig, ka, oldset, regs);
1da177e4	554
283828f3	555	if (ret == 0) {
1da177e4 LT	556	spin_lock_irq(&current->sighand->siglock);
1da177e4 LT	557	sigorsets(&current->blocked,&current->blocked,&ka->sa.sa_mask);
69be8f18 SR	558	if (!(ka->sa.sa_flags & SA_NODEFER))
69be8f18 SR	559	sigaddset(&current->blocked,sig);
1da177e4 LT	560	recalc_sigpending();
	561	spin_unlock_irq(&current->sighand->siglock);
	562	}
7c1def16 RM	563
7c1def16 RM	564	return ret;
1da177e4 LT	565	}
	566
	567	/*
	568	* Note that 'init' is a special process: it doesn't get signals it doesn't
	569	* want to handle. Thus you cannot kill init even with a SIGKILL even by
	570	* mistake.
	571	*/
283828f3	572	static void fastcall do_signal(struct pt_regs *regs)
1da177e4 LT	573	{
	574	siginfo_t info;
	575	int signr;
	576	struct k_sigaction ka;
283828f3	577	sigset_t *oldset;
1da177e4 LT	578
	579	/*
	580	* We want the common case to go fast, which
	581	* is why we may in certain cases get here from
	582	* kernel mode. Just return without doing anything
0998e422 ZA	583	* if so. vm86 regs switched out by assembly code
	584	* before reaching here, so testing against kernel
	585	* CS suffices.
1da177e4	586	*/
717b594a	587	if (!user_mode(regs))
283828f3	588	return;
1da177e4	589
283828f3 DH	590	if (test_thread_flag(TIF_RESTORE_SIGMASK))
	591	oldset = &current->saved_sigmask;
	592	else
1da177e4 LT	593	oldset = &current->blocked;
	594
	595	signr = get_signal_to_deliver(&info, &ka, regs, NULL);
	596	if (signr > 0) {
27b46d76	597	/* Re-enable any watchpoints before delivering the
1da177e4 LT	598	* signal to user space. The processor register will
	599	* have been cleared if the watchpoint triggered
	600	* inside the kernel.
	601	*/
283828f3	602	if (unlikely(current->thread.debugreg[7]))
1cc6f12e	603	set_debugreg(current->thread.debugreg[7], 7);
1da177e4 LT	604
1da177e4 LT	605	/* Whee! Actually deliver the signal. */
283828f3 DH	606	if (handle_signal(signr, &info, &ka, oldset, regs) == 0) {
	607	/* a signal was successfully delivered; the saved
	608	* sigmask will have been stored in the signal frame,
	609	* and will be restored by sigreturn, so we can simply
	610	* clear the TIF_RESTORE_SIGMASK flag */
	611	if (test_thread_flag(TIF_RESTORE_SIGMASK))
	612	clear_thread_flag(TIF_RESTORE_SIGMASK);
	613	}
	614
	615	return;
1da177e4 LT	616	}
1da177e4 LT	617
1da177e4 LT	618	/* Did we come from a system call? */
	619	if (regs->orig_eax >= 0) {
	620	/* Restart the system call - no handlers present */
283828f3 DH	621	switch (regs->eax) {
	622	case -ERESTARTNOHAND:
	623	case -ERESTARTSYS:
	624	case -ERESTARTNOINTR:
1da177e4 LT	625	regs->eax = regs->orig_eax;
1da177e4 LT	626	regs->eip -= 2;
283828f3 DH	627	break;
	628
	629	case -ERESTART_RESTARTBLOCK:
1da177e4 LT	630	regs->eax = __NR_restart_syscall;
1da177e4 LT	631	regs->eip -= 2;
283828f3	632	break;
1da177e4 LT	633	}
1da177e4 LT	634	}
283828f3 DH	635
	636	/* if there's no signal to deliver, we just put the saved sigmask
	637	* back */
	638	if (test_thread_flag(TIF_RESTORE_SIGMASK)) {
	639	clear_thread_flag(TIF_RESTORE_SIGMASK);
	640	sigprocmask(SIG_SETMASK, &current->saved_sigmask, NULL);
	641	}
1da177e4 LT	642	}
	643
	644	/*
	645	* notification of userspace execution resumption
283828f3	646	* - triggered by the TIF_WORK_MASK flags
1da177e4 LT	647	*/
1da177e4 LT	648	__attribute__((regparm(3)))
283828f3	649	void do_notify_resume(struct pt_regs regs, void _unused,
1da177e4 LT	650	__u32 thread_info_flags)
	651	{
	652	/* Pending single-step? */
	653	if (thread_info_flags & _TIF_SINGLESTEP) {
	654	regs->eflags \|= TF_MASK;
	655	clear_thread_flag(TIF_SINGLESTEP);
	656	}
283828f3	657
1da177e4	658	/* deal with pending signal delivery */
283828f3 DH	659	if (thread_info_flags & (_TIF_SIGPENDING \| _TIF_RESTORE_SIGMASK))
283828f3 DH	660	do_signal(regs);
1da177e4 LT	661
	662	clear_thread_flag(TIF_IRET);
	663	}