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>

1 files changed, 34 insertions, 21 deletions

diff --git a/arch/sparc/kernel/signal32.c b/arch/sparc/kernel/signal32.c
index 76b67c4c6aa4..643a354795cc 100644
--- a/arch/sparc/kernel/signal32.c
+++ b/arch/sparc/kernel/signal32.c
@@ -511,8 +511,8 @@ out_irqs_on:
 
 }
 
-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 @@ static void setup_frame32(struct k_sigaction *ka, struct pt_regs *regs,
 
 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 @@ static void setup_rt_frame32(struct k_sigaction *ka, struct pt_regs *regs,
 
                 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 @@ static inline void handle_signal32(unsigned long signr, struct k_sigaction *ka,
                 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 @@ void do_signal32(sigset_t *oldset, struct pt_regs * regs,
         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 &&