[PATCH 6/6] x86: signal: sys_rt_sigreturn() should use sigprocmask()

[Oleg Nesterov <oleg@redhat.com>]

Normally sys_rt_sigreturn() restores the old current->blocked which was
changed by handle_signal(), and unblocking is always fine.

But the debugger or application itself can change frame->uc_sigmask and
thus we need sigprocmask()->retarget_shared_pending().

Signed-off-by: Oleg Nesterov <oleg@redhat.com>
---

 arch/x86/kernel/signal.c |    5 +----
 1 file changed, 1 insertion(+), 4 deletions(-)

--- sigprocmask/arch/x86/kernel/signal.c~6_sigreturn	2011-04-11 18:33:17.000000000 +0200
+++ sigprocmask/arch/x86/kernel/signal.c	2011-04-11 18:57:27.000000000 +0200
@@ -601,10 +601,7 @@ long sys_rt_sigreturn(struct pt_regs *re
 		goto badframe;
 
 	sigdelsetmask(&set, ~_BLOCKABLE);
-	spin_lock_irq(&current->sighand->siglock);
-	current->blocked = set;
-	recalc_sigpending();
-	spin_unlock_irq(&current->sighand->siglock);
+	sigprocmask(SIG_SETMASK, &set, NULL);
 
 	if (restore_sigcontext(regs, &frame->uc.uc_mcontext, &ax))
 		goto badframe;