ptrace: partially fix the do_wait(WEXITED) vs EXIT_DEAD->EXIT_ZOMBIE race

[pandora-kernel.git] / kernel / exit.c

diff --git a/kernel/exit.c b/kernel/exit.c
index d0b7d98..e6e01b9 100644 (file)
--- a/kernel/exit.c
+++ b/kernel/exit.c
@@ -1540,8 +1540,15 @@ static int wait_consider_task(struct wait_opts *wo, int ptrace,
        }
 
        /* dead body doesn't have much to contribute */
-       if (p->exit_state == EXIT_DEAD)
+       if (unlikely(p->exit_state == EXIT_DEAD)) {
+               /*
+                * But do not ignore this task until the tracer does
+                * wait_task_zombie()->do_notify_parent().
+                */
+               if (likely(!ptrace) && unlikely(ptrace_reparented(p)))
+                       wo->notask_error = 0;
                return 0;
+       }
 
        /* slay zombie? */
        if (p->exit_state == EXIT_ZOMBIE) {