lk/linux-kernel-test
1
0
Fork 0
Code Issues Pull Requests Releases Wiki Activity

[ARM] 3168/1: Update ARM signal delivery and masking

Browse Source 
Patch from Daniel Jacobowitz

After delivering a signal (creating its stack frame) we must check for
additional pending unblocked signals before returning to userspace.
Otherwise signals may be delayed past the next syscall or reschedule.

Once that was fixed it became obvious that the ARM signal mask manipulation
was broken.  It was a little bit broken before the recent SA_NODEFER
changes, and then very broken after them.  We must block the requested
signals before starting the handler or the same signal can be delivered
again before the handler even gets a chance to run.

Signed-off-by: Daniel Jacobowitz <dan@codesourcery.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
This commit is contained in:
Daniel Jacobowitz
2005-11-19 10:01:07 +00:00
committed by Russell King
parent d2c5b69099
commit a6c61e9dfd
4 changed files with 14 additions and 201 deletions
Download Patch File Download Diff File Expand all files Collapse all files

25
arch/arm/kernel/signal.c
View File

@ -595,23 +595,22 @@ handle_signal(unsigned long sig, struct k_sigaction *ka,
*/
ret |= !valid_user_regs(regs);
/*
* Block the signal if we were unsuccessful.
*/
if (ret != 0) {
spin_lock_irq(&tsk->sighand->siglock);
sigorsets(&tsk->blocked, &tsk->blocked,
&ka->sa.sa_mask);
if (!(ka->sa.sa_flags & SA_NODEFER))
sigaddset(&tsk->blocked, sig);
recalc_sigpending();
spin_unlock_irq(&tsk->sighand->siglock);
force_sigsegv(sig, tsk);
return;
}
if (ret == 0)
return;
/*
* Block the signal if we were successful.
*/
spin_lock_irq(&tsk->sighand->siglock);
sigorsets(&tsk->blocked, &tsk->blocked,
&ka->sa.sa_mask);
if (!(ka->sa.sa_flags & SA_NODEFER))
sigaddset(&tsk->blocked, sig);
recalc_sigpending();
spin_unlock_irq(&tsk->sighand->siglock);
force_sigsegv(sig, tsk);
}
/*