commit 392c21802ee3aa85cee0e703105f797a8a7b9416
author David S. Miller <davem@davemloft.net> Tue Sep 21 21:41:12 2010 -0700
committer David S. Miller <davem@davemloft.net> Tue Sep 21 21:41:12 2010 -0700
tree d0b40070dbd80817f069a5b033044e6370b55f26
parent 05c5e7698bdc54b3079a3517d86077f49ebcc788

sparc: Don't mask signal when we can't setup signal frame.

Don't invoke the signal handler tracehook in that situation
either.

Reported-by: Al Viro <viro@ZenIV.linux.org.uk>
Signed-off-by: David S. Miller <davem@davemloft.net>

arch/sparc/kernel/signal32.c

diff --git a/arch/sparc/kernel/signal32.c b/arch/sparc/kernel/signal32.c
index 76b67c4..643a354 100644
--- a/arch/sparc/kernel/signal32.c
+++ b/arch/sparc/kernel/signal32.c
@@ -511,8 +511,8 @@
 
 }
 
-static void setup_frame32(struct k_sigaction *ka, struct pt_regs *regs,
-			  int signo, sigset_t *oldset)
+static int setup_frame32(struct k_sigaction *ka, struct pt_regs *regs,
+			 int signo, sigset_t *oldset)
 {
 	struct signal_frame32 __user *sf;
 	int sigframe_size;
@@ -620,13 +620,16 @@
 
 sigill:
 	do_exit(SIGILL);
+	return -EINVAL;
+
 sigsegv:
 	force_sigsegv(signo, current);
+	return -EFAULT;
 }
 
-static void setup_rt_frame32(struct k_sigaction *ka, struct pt_regs *regs,
-			     unsigned long signr, sigset_t *oldset,
-			     siginfo_t *info)
+static int setup_rt_frame32(struct k_sigaction *ka, struct pt_regs *regs,
+			    unsigned long signr, sigset_t *oldset,
+			    siginfo_t *info)
 {
 	struct rt_signal_frame32 __user *sf;
 	int sigframe_size;
@@ -738,22 +741,30 @@
 
 		flush_signal_insns(address);
 	}
-	return;
+	return 0;
 
 sigill:
 	do_exit(SIGILL);
+	return -EINVAL;
+
 sigsegv:
 	force_sigsegv(signr, current);
+	return -EFAULT;
 }
 
-static inline void handle_signal32(unsigned long signr, struct k_sigaction *ka,
-				   siginfo_t *info,
-				   sigset_t *oldset, struct pt_regs *regs)
+static inline int handle_signal32(unsigned long signr, struct k_sigaction *ka,
+				  siginfo_t *info,
+				  sigset_t *oldset, struct pt_regs *regs)
 {
+	int err;
+
 	if (ka->sa.sa_flags & SA_SIGINFO)
-		setup_rt_frame32(ka, regs, signr, oldset, info);
+		err = setup_rt_frame32(ka, regs, signr, oldset, info);
 	else
-		setup_frame32(ka, regs, signr, oldset);
+		err = setup_frame32(ka, regs, signr, oldset);
+
+	if (err)
+		return err;
 
 	spin_lock_irq(&current->sighand->siglock);
 	sigorsets(&current->blocked,&current->blocked,&ka->sa.sa_mask);
@@ -761,6 +772,10 @@
 		sigaddset(&current->blocked,signr);
 	recalc_sigpending();
 	spin_unlock_irq(&current->sighand->siglock);
+
+	tracehook_signal_handler(signr, info, ka, regs, 0);
+
+	return 0;
 }
 
 static inline void syscall_restart32(unsigned long orig_i0, struct pt_regs *regs,
@@ -807,16 +822,14 @@
 	if (signr > 0) {
 		if (restart_syscall)
 			syscall_restart32(orig_i0, regs, &ka.sa);
-		handle_signal32(signr, &ka, &info, 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 TS_RESTORE_SIGMASK flag.
-		 */
-		current_thread_info()->status &= ~TS_RESTORE_SIGMASK;
-
-		tracehook_signal_handler(signr, &info, &ka, regs, 0);
+		if (handle_signal32(signr, &ka, &info, oldset, regs) == 0) {
+			/* 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 TS_RESTORE_SIGMASK flag.
+			 */
+			current_thread_info()->status &= ~TS_RESTORE_SIGMASK;
+		}
 		return;
 	}
 	if (restart_syscall &&