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, 33 insertions, 20 deletions

diff --git a/arch/sparc/kernel/signal_32.c b/arch/sparc/kernel/signal_32.c
index 9882df92ba0a..99c85e99bbcf 100644
--- a/arch/sparc/kernel/signal_32.c
+++ b/arch/sparc/kernel/signal_32.c
@@ -315,8 +315,8 @@ save_fpu_state(struct pt_regs *regs, __siginfo_fpu_t __user *fpu)
         return err;
 }
 
-static void setup_frame(struct k_sigaction *ka, struct pt_regs *regs,
-                        int signo, sigset_t *oldset)
+static int setup_frame(struct k_sigaction *ka, struct pt_regs *regs,
+                       int signo, sigset_t *oldset)
 {
         struct signal_frame __user *sf;
         int sigframe_size, err;
@@ -384,16 +384,19 @@ static void setup_frame(struct k_sigaction *ka, struct pt_regs *regs,
                 /* Flush instruction space. */
                 flush_sig_insns(current->mm, (unsigned long) &(sf->insns[0]));
         }
-        return;
+        return 0;
 
 sigill_and_return:
         do_exit(SIGILL);
+        return -EINVAL;
+
 sigsegv:
         force_sigsegv(signo, current);
+        return -EFAULT;
 }
 
-static void setup_rt_frame(struct k_sigaction *ka, struct pt_regs *regs,
-                           int signo, sigset_t *oldset, siginfo_t *info)
+static int setup_rt_frame(struct k_sigaction *ka, struct pt_regs *regs,
+                          int signo, sigset_t *oldset, siginfo_t *info)
 {
         struct rt_signal_frame __user *sf;
         int sigframe_size;
@@ -466,22 +469,30 @@ static void setup_rt_frame(struct k_sigaction *ka, struct pt_regs *regs,
                 /* Flush instruction space. */
                 flush_sig_insns(current->mm, (unsigned long) &(sf->insns[0]));
         }
-        return;
+        return 0;
 
 sigill:
         do_exit(SIGILL);
+        return -EINVAL;
+
 sigsegv:
         force_sigsegv(signo, current);
+        return -EFAULT;
 }
 
-static inline void
+static inline int
 handle_signal(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_frame(ka, regs, signr, oldset, info);
+                err = setup_rt_frame(ka, regs, signr, oldset, info);
         else
-                setup_frame(ka, regs, signr, oldset);
+                err = setup_frame(ka, regs, signr, oldset);
+
+        if (err)
+                return err;
 
         spin_lock_irq(&current->sighand->siglock);
         sigorsets(&current->blocked,&current->blocked,&ka->sa.sa_mask);
@@ -489,6 +500,10 @@ handle_signal(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_restart(unsigned long orig_i0, struct pt_regs *regs,
@@ -546,17 +561,15 @@ static void do_signal(struct pt_regs *regs, unsigned long orig_i0)
         if (signr > 0) {
                 if (restart_syscall)
                         syscall_restart(orig_i0, regs, &ka.sa);
-                handle_signal(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 TIF_RESTORE_SIGMASK flag.
-                 */
-                if (test_thread_flag(TIF_RESTORE_SIGMASK))
-                        clear_thread_flag(TIF_RESTORE_SIGMASK);
-
-                tracehook_signal_handler(signr, &info, &ka, regs, 0);
+                if (handle_signal(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 TIF_RESTORE_SIGMASK flag.
+                         */
+                        if (test_thread_flag(TIF_RESTORE_SIGMASK))
+                                clear_thread_flag(TIF_RESTORE_SIGMASK);
+                }
                 return;
         }
         if (restart_syscall &&