[PATCH 02/41] arm: Use set_current_blocked()

Matt Fleming
2011-08-11T13:57:24Z

From: Matt Fleming <matt.fleming@linux.intel.com>

As described in e6fa16ab ("signal: sigprocmask() should do
retarget_shared_pending()") the modification of current->blocked is
incorrect as we need to check for shared signals we're about to block.

Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Russell King <linux@arm.linux.org.uk>
Cc: Arnd Bergmann <arnd.bergmann@linaro.org>
Cc: Dave Martin <dave.martin@linaro.org>
Cc: Nicolas Pitre <nicolas.pitre@linaro.org>
CC: Will Deacon <will.deacon@arm.com>
Signed-off-by: Matt Fleming <matt.fleming@linux.intel.com>
---
arch/arm/kernel/signal.c | 25 +++++++++++--------------
1 files changed, 11 insertions(+), 14 deletions(-)

diff --git a/arch/arm/kernel/signal.c b/arch/arm/kernel/signal.c
index 0340224..b97668a 100644
--- a/arch/arm/kernel/signal.c
+++ b/arch/arm/kernel/signal.c
@@ -66,12 +66,13 @@ const unsigned long syscall_restart_code[2] = {
*/
asmlinkage int sys_sigsuspend(int restart, unsigned long oldmask, old_sigset_t mask)
{
- mask &= _BLOCKABLE;
- spin_lock_irq(&current->sighand->siglock);
+ sigset_t blocked;
+
current->saved_sigmask = current->blocked;
- siginitset(&current->blocked, mask);
- recalc_sigpending();
- spin_unlock_irq(&current->sighand->siglock);
+
+ mask &= _BLOCKABLE;
+ siginitset(&blocked, mask);
+ set_current_block(&blocked);

current->state = TASK_INTERRUPTIBLE;
schedule();
@@ -281,10 +282,7 @@ static int restore_sigframe(struct pt_regs *regs, struct sigframe __user *sf)
err = __copy_from_user(&set, &sf->uc.uc_sigmask, sizeof(set));
if (err == 0) {
sigdelsetmask(&set, ~_BLOCKABLE);
- spin_lock_irq(&current->sighand->siglock);
- current->blocked = set;
- recalc_sigpending();
- spin_unlock_irq(&current->sighand->siglock);
+ set_current_blocked(&set);
}

__get_user_error(regs->ARM_r0, &sf->uc.uc_mcontext.arm_r0, err);
@@ -607,6 +605,7 @@ handle_signal(unsigned long sig, struct k_sigaction *ka,
{
struct thread_info *thread = current_thread_info();
struct task_struct *tsk = current;
+ sigset_t blocked;
int usig = sig;
int ret;

@@ -637,13 +636,11 @@ handle_signal(unsigned long sig, struct k_sigaction *ka,
/*
* Block the signal if we were successful.
*/
- spin_lock_irq(&tsk->sighand->siglock);
- sigorsets(&tsk->blocked, &tsk->blocked,
+ sigorsets(&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);
+ sigaddset(&blocked, sig);
+ set_current_blocked(&blocked);

return 0;
}
--
1.7.4.4