Commit f9369910 authored by Linus Torvalds's avatar Linus Torvalds
Browse files

Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/signal 

Pull first series of signal handling cleanups from Al Viro:
 "This is just the first part of the queue (about a half of it);
  assorted fixes all over the place in signal handling.

  This one ends with all sigsuspend() implementations switched to
  generic one (->saved_sigmask-based).

  With this, a bunch of assorted old buglets are fixed and most of the
  missing bits of NOTIFY_RESUME hookup are in place.  Two more fixes sit
  in arm and um trees respectively, and there's a couple of broken ones
  that need obvious fixes - parisc and avr32 check TIF_NOTIFY_RESUME
  only on one of two codepaths; fixes for that will happen in the next
  series"

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/signal: (55 commits)
  unicore32: if there's no handler we need to restore sigmask, syscall or no syscall
  xtensa: add handling of TIF_NOTIFY_RESUME
  microblaze: drop 'oldset' argument of do_notify_resume()
  microblaze: handle TIF_NOTIFY_RESUME
  score: add handling of NOTIFY_RESUME to do_notify_resume()
  m68k: add TIF_NOTIFY_RESUME and handle it.
  sparc: kill ancient comment in sparc_sigaction()
  h8300: missing checks of __get_user()/__put_user() return values
  frv: missing checks of __get_user()/__put_user() return values
  cris: missing checks of __get_user()/__put_user() return values
  powerpc: missing checks of __get_user()/__put_user() return values
  sh: missing checks of __get_user()/__put_user() return values
  sparc: missing checks of __get_user()/__put_user() return values
  avr32: struct old_sigaction is never used
  m32r: struct old_sigaction is never used
  xtensa: xtensa_sigaction doesn't exist
  alpha: tidy signal delivery up
  score: don't open-code force_sigsegv()
  cris: don't open-code force_sigsegv()
  blackfin: don't open-code force_sigsegv()
  ...
parents 05f144a0 415d04d0

arch/alpha/kernel/signal.c

+27 −53
Original line number Diff line number Diff line
@@ -34,9 +34,6 @@ 
#define _BLOCKABLE (~(sigmask(SIGKILL) | sigmask(SIGSTOP)))



asmlinkage void ret_from_sys_call(void);

static void do_signal(struct pt_regs *, struct switch_stack *,

		      unsigned long, unsigned long);





/*

 * The OSF/1 sigprocmask calling sequence is different from the
@@ -121,17 +118,8 @@ SYSCALL_DEFINE5(rt_sigaction, int, sig, const struct sigaction __user *, act, 
SYSCALL_DEFINE1(sigsuspend, old_sigset_t, mask)

{

	sigset_t blocked;



	current->saved_sigmask = current->blocked;



	mask &= _BLOCKABLE;

	siginitset(&blocked, mask);

	set_current_blocked(&blocked);



	current->state = TASK_INTERRUPTIBLE;

	schedule();

	set_thread_flag(TIF_RESTORE_SIGMASK);

	return -ERESTARTNOHAND;

	return sigsuspend(&blocked);

}



asmlinkage int
@@ -376,11 +364,11 @@ setup_frame(int sig, struct k_sigaction *ka, sigset_t *set, 
	oldsp = rdusp();

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

	if (!access_ok(VERIFY_WRITE, frame, sizeof(*frame)))

		goto give_sigsegv;

		return -EFAULT;



	err |= setup_sigcontext(&frame->sc, regs, sw, set->sig[0], oldsp);

	if (err)

		goto give_sigsegv;

		return -EFAULT;



	/* Set up to return from userspace.  If provided, use a stub

	   already in userspace.  */
@@ -396,7 +384,7 @@ setup_frame(int sig, struct k_sigaction *ka, sigset_t *set, 


	/* Check that everything was written properly.  */

	if (err)

		goto give_sigsegv;

		return err;



	/* "Return" to the handler */

	regs->r26 = r26;
@@ -410,12 +398,7 @@ setup_frame(int sig, struct k_sigaction *ka, sigset_t *set, 
	printk("SIG deliver (%s:%d): sp=%p pc=%p ra=%p\n",

		current->comm, current->pid, frame, regs->pc, regs->r26);

#endif



	return 0;



give_sigsegv:

	force_sigsegv(sig, current);

	return -EFAULT;

}



static int
@@ -428,7 +411,7 @@ setup_rt_frame(int sig, struct k_sigaction *ka, siginfo_t *info, 
	oldsp = rdusp();

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

	if (!access_ok(VERIFY_WRITE, frame, sizeof(*frame)))

		goto give_sigsegv;

		return -EFAULT;



	err |= copy_siginfo_to_user(&frame->info, info);
@@ -443,7 +426,7 @@ setup_rt_frame(int sig, struct k_sigaction *ka, siginfo_t *info, 
				set->sig[0], oldsp);

	err |= __copy_to_user(&frame->uc.uc_sigmask, set, sizeof(*set));

	if (err)

		goto give_sigsegv;

		return -EFAULT;



	/* Set up to return from userspace.  If provided, use a stub

	   already in userspace.  */
@@ -459,7 +442,7 @@ setup_rt_frame(int sig, struct k_sigaction *ka, siginfo_t *info, 
	}



	if (err)

		goto give_sigsegv;

		return -EFAULT;



	/* "Return" to the handler */

	regs->r26 = r26;
@@ -475,31 +458,37 @@ setup_rt_frame(int sig, struct k_sigaction *ka, siginfo_t *info, 
#endif



	return 0;



give_sigsegv:

	force_sigsegv(sig, current);

	return -EFAULT;

}





/*

 * OK, we're invoking a handler.

 */

static inline int

static inline void

handle_signal(int sig, struct k_sigaction *ka, siginfo_t *info,

	      sigset_t *oldset, struct pt_regs * regs, struct switch_stack *sw)

	      struct pt_regs * regs, struct switch_stack *sw)

{

	sigset_t *oldset = &current->blocked;

	int ret;



	if (test_thread_flag(TIF_RESTORE_SIGMASK))

		oldset = &current->saved_sigmask;



	if (ka->sa.sa_flags & SA_SIGINFO)

		ret = setup_rt_frame(sig, ka, info, oldset, regs, sw);

	else

		ret = setup_frame(sig, ka, oldset, regs, sw);



	if (ret == 0)

	if (ret) {

		force_sigsegv(sig, current);

		return;

	}

	block_sigmask(ka, sig);



	return ret;

	/* A signal was successfully delivered, and the

	   saved sigmask was stored on the signal frame,

	   and will be restored by sigreturn.  So we can

	   simply clear the restore sigmask flag.  */

	clear_thread_flag(TIF_RESTORE_SIGMASK);

}



static inline void
@@ -547,12 +536,6 @@ do_signal(struct pt_regs * regs, struct switch_stack * sw, 
	int signr;

	unsigned long single_stepping = ptrace_cancel_bpt(current);

	struct k_sigaction ka;

	sigset_t *oldset;



	if (test_thread_flag(TIF_RESTORE_SIGMASK))

		oldset = &current->saved_sigmask;

	else

		oldset = &current->blocked;



	/* This lets the debugger run, ... */

	signr = get_signal_to_deliver(&info, &ka, regs, NULL);
@@ -564,14 +547,7 @@ do_signal(struct pt_regs * regs, struct switch_stack * sw, 
		/* Whee!  Actually deliver the signal.  */

		if (r0)

			syscall_restart(r0, r19, regs, &ka);

		if (handle_signal(signr, &ka, &info, oldset, regs, sw) == 0) {

			/* A signal was successfully delivered, and the

			   saved sigmask was stored on the signal frame,

			   and will be restored by sigreturn.  So we can

			   simply clear the restore sigmask flag.  */

			if (test_thread_flag(TIF_RESTORE_SIGMASK))

				clear_thread_flag(TIF_RESTORE_SIGMASK);

		}

		handle_signal(signr, &ka, &info, regs, sw);

		if (single_stepping) 

			ptrace_set_bpt(current); /* re-set bpt */

		return;
@@ -596,10 +572,8 @@ do_signal(struct pt_regs * regs, struct switch_stack * sw, 
	}



	/* If there's no signal to deliver, we just restore the saved mask.  */

	if (test_thread_flag(TIF_RESTORE_SIGMASK)) {

		clear_thread_flag(TIF_RESTORE_SIGMASK);

		sigprocmask(SIG_SETMASK, &current->saved_sigmask, NULL);

	}

	if (test_and_clear_thread_flag(TIF_RESTORE_SIGMASK))

		set_current_blocked(&current->saved_sigmask);



	if (single_stepping)

		ptrace_set_bpt(current);	/* re-set breakpoint */
@@ -610,7 +584,7 @@ do_notify_resume(struct pt_regs *regs, struct switch_stack *sw, 
		 unsigned long thread_info_flags,

		 unsigned long r0, unsigned long r19)

{

	if (thread_info_flags & (_TIF_SIGPENDING | _TIF_RESTORE_SIGMASK))

	if (thread_info_flags & _TIF_SIGPENDING)

		do_signal(regs, sw, r0, r19);



	if (thread_info_flags & _TIF_NOTIFY_RESUME) {

arch/arm/kernel/signal.c

+1 −10
Original line number Diff line number Diff line
@@ -67,17 +67,8 @@ const unsigned long syscall_restart_code[2] = { 
asmlinkage int sys_sigsuspend(int restart, unsigned long oldmask, old_sigset_t mask)

{

	sigset_t blocked;



	current->saved_sigmask = current->blocked;



	mask &= _BLOCKABLE;

	siginitset(&blocked, mask);

	set_current_blocked(&blocked);



	current->state = TASK_INTERRUPTIBLE;

	schedule();

	set_restore_sigmask();

	return -ERESTARTNOHAND;

	return sigsuspend(&blocked);

}



asmlinkage int

arch/avr32/include/asm/signal.h

+0 −7
Original line number Diff line number Diff line
@@ -115,13 +115,6 @@ typedef unsigned long sigset_t; 
#include <asm-generic/signal-defs.h>



#ifdef __KERNEL__

struct old_sigaction {

	__sighandler_t sa_handler;

	old_sigset_t sa_mask;

	unsigned long sa_flags;

	__sigrestore_t sa_restorer;

};



struct sigaction {

	__sighandler_t sa_handler;

	unsigned long sa_flags;

arch/avr32/kernel/signal.c

+12 −18
Original line number Diff line number Diff line
@@ -77,6 +77,9 @@ asmlinkage int sys_rt_sigreturn(struct pt_regs *regs) 
	struct rt_sigframe __user *frame;

	sigset_t set;



	/* Always make any pending restarted system calls return -EINTR */

	current_thread_info()->restart_block.fn = do_no_restart_syscall;



	frame = (struct rt_sigframe __user *)regs->sp;

	pr_debug("SIG return: frame = %p\n", frame);
@@ -87,10 +90,7 @@ asmlinkage int sys_rt_sigreturn(struct pt_regs *regs) 
		goto badframe;



	sigdelsetmask(&set, ~_BLOCKABLE);

	spin_lock_irq(&current->sighand->siglock);

	current->blocked = set;

	recalc_sigpending();

	spin_unlock_irq(&current->sighand->siglock);

	set_current_blocked(&set);



	if (restore_sigcontext(regs, &frame->uc.uc_mcontext))

		goto badframe;
@@ -238,22 +238,16 @@ handle_signal(unsigned long sig, struct k_sigaction *ka, siginfo_t *info, 
	 */

	ret |= !valid_user_regs(regs);



	/*

	 * Block the signal if we were unsuccessful.

	 */

	if (ret != 0 || !(ka->sa.sa_flags & SA_NODEFER)) {

		spin_lock_irq(&current->sighand->siglock);

		sigorsets(&current->blocked, &current->blocked,

			  &ka->sa.sa_mask);

		sigaddset(&current->blocked, sig);

		recalc_sigpending();

		spin_unlock_irq(&current->sighand->siglock);

	}



	if (ret == 0)

	if (ret != 0) {

		force_sigsegv(sig, current);

		return;

	}



	force_sigsegv(sig, current);

	/*

	 * Block the signal if we were successful.

	 */

	block_sigmask(ka, sig);

	clear_thread_flag(TIF_RESTORE_SIGMASK);

}



/*

arch/blackfin/kernel/signal.c

+5 −16
Original line number Diff line number Diff line
@@ -99,10 +99,7 @@ asmlinkage int do_rt_sigreturn(unsigned long __unused) 
		goto badframe;



	sigdelsetmask(&set, ~_BLOCKABLE);

	spin_lock_irq(&current->sighand->siglock);

	current->blocked = set;

	recalc_sigpending();

	spin_unlock_irq(&current->sighand->siglock);

	set_current_blocked(&set);



	if (rt_restore_sigcontext(regs, &frame->uc.uc_mcontext, &r0))

		goto badframe;
@@ -213,9 +210,7 @@ setup_rt_frame(int sig, struct k_sigaction *ka, siginfo_t * info, 
	return 0;



 give_sigsegv:

	if (sig == SIGSEGV)

		ka->sa.sa_handler = SIG_DFL;

	force_sig(SIGSEGV, current);

	force_sigsegv(sig, current);

	return -EFAULT;

}
@@ -266,15 +261,9 @@ handle_signal(int sig, siginfo_t *info, struct k_sigaction *ka, 
	/* set up the stack frame */

	ret = setup_rt_frame(sig, ka, info, 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);

	}

	if (ret == 0)

		block_sigmask(ka, sig);



	return ret;

}

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