signal: add block_sigmask() for adding sigmask to current->blocked

Abstract the code sequence for adding a signal handler's sa_mask to
current->blocked because the sequence is identical for all architectures.
Furthermore, in the past some architectures actually got this code wrong,
so introduce a wrapper that all architectures can use.

Signed-off-by: Matt Fleming <matt.fleming@intel.com>
Signed-off-by: Oleg Nesterov <oleg@redhat.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Tejun Heo <tj@kernel.org>
Cc: "David S. Miller" <davem@davemloft.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

1 files changed, 1 insertions, 5 deletions

diff --git a/arch/x86/kernel/signal.c b/arch/x86/kernel/signal.c
index 54ddaeb221c1..46a01bdc27e2 100644
--- a/arch/x86/kernel/signal.c
+++ b/arch/x86/kernel/signal.c
@@ -682,7 +682,6 @@ static int
 handle_signal(unsigned long sig, siginfo_t *info, struct k_sigaction *ka,
                 struct pt_regs *regs)
 {
-        sigset_t blocked;
         int ret;
 
         /* Are we from a system call? */
@@ -733,10 +732,7 @@ handle_signal(unsigned long sig, siginfo_t *info, struct k_sigaction *ka,
          */
         regs->flags &= ~X86_EFLAGS_TF;
 
-        sigorsets(&blocked, &current->blocked, &ka->sa.sa_mask);
-        if (!(ka->sa.sa_flags & SA_NODEFER))
-                sigaddset(&blocked, sig);
-        set_current_blocked(&blocked);
+        block_sigmask(ka, sig);
 
         tracehook_signal_handler(sig, info, ka, regs,
                                  test_thread_flag(TIF_SINGLESTEP));