1 files changed, 5 insertions, 2 deletions

diff --git a/kernel/exit.c b/kernel/exit.c
index 13ae64001fec..628d41f0dd54 100644
--- a/kernel/exit.c
+++ b/kernel/exit.c
@@ -1197,8 +1197,11 @@ static int wait_task_zombie(struct wait_opts *wo, struct task_struct *p)
         }
 
         traced = ptrace_reparented(p);
-
-        if (likely(!traced)) {
+        /*
+         * It can be ptraced but not reparented, check
+         * !task_detached() to filter out sub-threads.
+         */
+        if (likely(!traced) && likely(!task_detached(p))) {
                 struct signal_struct *psig;
                 struct signal_struct *sig;