[PATCH 20/41] OpenRISC: Don't mask signals if we fail to setup signal stack

Matt Fleming
2011-08-11T14:03:23Z

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

setup_rt_frame() needs to return an indication of whether it succeeded
or failed in setting up the signal stack frame. If setup_rt_frame()
fails then we must not modify current->blocked.

Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Jonas Bonn <jonas@southpole.se>
Cc: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Matt Fleming <matt.fleming@intel.com>
---
arch/openrisc/kernel/signal.c | 29 ++++++++++++++++++-----------
1 files changed, 18 insertions(+), 11 deletions(-)

diff --git a/arch/openrisc/kernel/signal.c b/arch/openrisc/kernel/signal.c
index 2f75e74..b0bdfda 100644
--- a/arch/openrisc/kernel/signal.c
+++ b/arch/openrisc/kernel/signal.c
@@ -196,8 +196,8 @@ static inline void __user *get_sigframe(struct k_sigaction *ka,
* trampoline which performs the syscall sigreturn, or a provided
* user-mode trampoline.
*/
-static void setup_rt_frame(int sig, struct k_sigaction *ka, siginfo_t *info,
- sigset_t *set, struct pt_regs *regs)
+static int setup_rt_frame(int sig, struct k_sigaction *ka, siginfo_t *info,
+ sigset_t *set, struct pt_regs *regs)
{
struct rt_sigframe *frame;
unsigned long return_ip;
@@ -254,18 +254,23 @@ static void setup_rt_frame(int sig, struct k_sigaction *ka, siginfo_t *info,
/* actually move the usp to reflect the stacked frame */
regs->sp = (unsigned long)frame;

- return;
+ return 0;

give_sigsegv:
force_sigsegv(sig, current);
+ return -EFAULT;
}

-static inline void
+static inline int
handle_signal(unsigned long sig,
siginfo_t *info, struct k_sigaction *ka,
sigset_t *oldset, struct pt_regs *regs)
{
- setup_rt_frame(sig, ka, info, oldset, regs);
+ int ret;
+
+ ret = setup_rt_frame(sig, ka, info, oldset, regs);
+ if (ret)
+ return ret;

spin_lock_irq(&current->sighand->siglock);
sigorsets(&current->blocked, &current->blocked, &ka->sa.sa_mask);
@@ -274,6 +279,8 @@ handle_signal(unsigned long sig,
recalc_sigpending();

spin_unlock_irq(&current->sighand->siglock);
+
+ return 0;
}

/*
@@ -362,13 +369,13 @@ void do_signal(struct pt_regs *regs)
oldset = &current->blocked;

/* Whee! Actually deliver the signal. */
- handle_signal(signr, &info, &ka, oldset, regs);
- /* a signal was successfully delivered; the saved
- * sigmask will have been stored in the signal frame,
- * and will be restored by sigreturn, so we can simply
- * clear the TIF_RESTORE_SIGMASK flag */
- if (test_thread_flag(TIF_RESTORE_SIGMASK))
+ if (!handle_signal(signr, &info, &ka, oldset, regs)) {
+ /* a signal was successfully delivered; the saved
+ * sigmask will have been stored in the signal frame,
+ * and will be restored by sigreturn, so we can simply
+ * clear the TIF_RESTORE_SIGMASK flag */
clear_thread_flag(TIF_RESTORE_SIGMASK);
+ }

tracehook_signal_handler(signr, &info, &ka, regs,
test_thread_flag(TIF_SINGLESTEP));
--
1.7.4.4