1 files changed, 18 insertions, 4 deletions

diff --git a/kernel/signal.c b/kernel/signal.c
index 906ae5a1779c..4e3cff10fdce 100644
--- a/kernel/signal.c
+++ b/kernel/signal.c
@@ -637,7 +637,7 @@ static inline bool si_fromuser(const struct siginfo *info)
 
 /*
  * Bad permissions for sending the signal
- * - the caller must hold at least the RCU read lock
+ * - the caller must hold the RCU read lock
  */
 static int check_kill_permission(int sig, struct siginfo *info,
                                  struct task_struct *t)
@@ -1105,7 +1105,8 @@ int zap_other_threads(struct task_struct *p)
         return count;
 }
 
-struct sighand_struct *lock_task_sighand(struct task_struct *tsk, unsigned long *flags)
+struct sighand_struct *__lock_task_sighand(struct task_struct *tsk,
+                                           unsigned long *flags)
 {
         struct sighand_struct *sighand;
 
@@ -1127,11 +1128,14 @@ struct sighand_struct *lock_task_sighand(struct task_struct *tsk, unsigned long
 
 /*
  * send signal info to all the members of a group
- * - the caller must hold the RCU read lock at least
  */
 int group_send_sig_info(int sig, struct siginfo *info, struct task_struct *p)
 {
-        int ret = check_kill_permission(sig, info, p);
+        int ret;
+
+        rcu_read_lock();
+        ret = check_kill_permission(sig, info, p);
+        rcu_read_unlock();
 
         if (!ret && sig)
                 ret = do_send_sig_info(sig, info, p, true);
@@ -1614,6 +1618,8 @@ static int sigkill_pending(struct task_struct *tsk)
  * is gone, we keep current->exit_code unless clear_code.
  */
 static void ptrace_stop(int exit_code, int clear_code, siginfo_t *info)
+        __releases(&current->sighand->siglock)
+        __acquires(&current->sighand->siglock)
 {
         if (arch_ptrace_stop_needed(exit_code, info)) {
                 /*
@@ -2212,6 +2218,14 @@ int copy_siginfo_to_user(siginfo_t __user *to, siginfo_t *from)
 #ifdef __ARCH_SI_TRAPNO
                 err |= __put_user(from->si_trapno, &to->si_trapno);
 #endif
+#ifdef BUS_MCEERR_AO
+                /* 
+                 * Other callers might not initialize the si_lsb field,
+                 * so check explicitely for the right codes here.
+                 */
+                if (from->si_code == BUS_MCEERR_AR || from->si_code == BUS_MCEERR_AO)
+                        err |= __put_user(from->si_addr_lsb, &to->si_addr_lsb);
+#endif
                 break;
         case __SI_CHLD:
                 err |= __put_user(from->si_pid, &to->si_pid);