1 files changed, 12 insertions, 3 deletions

diff --git a/kernel/signal.c b/kernel/signal.c
index 3d3adb94561d..b0b43a4ad8dd 100644
--- a/kernel/signal.c
+++ b/kernel/signal.c
@@ -1050,17 +1050,26 @@ int kill_pgrp_info(int sig, struct siginfo *info, struct pid *pgrp)
 
 int kill_pid_info(int sig, struct siginfo *info, struct pid *pid)
 {
-        int error;
+        int error = -ESRCH;
         struct task_struct *p;
 
         rcu_read_lock();
         if (unlikely(sig_needs_tasklist(sig)))
                 read_lock(&tasklist_lock);
 
+retry:
         p = pid_task(pid, PIDTYPE_PID);
-        error = -ESRCH;
-        if (p)
+        if (p) {
                 error = group_send_sig_info(sig, info, p);
+                if (unlikely(error == -ESRCH))
+                        /*
+                         * The task was unhashed in between, try again.
+                         * If it is dead, pid_task() will return NULL,
+                         * if we race with de_thread() it will find the
+                         * new leader.
+                         */
+                        goto retry;
+        }
 
         if (unlikely(sig_needs_tasklist(sig)))
                 read_unlock(&tasklist_lock);