[PATCH] coredump: kill ptrace related stuff

With this patch zap_process() sets SIGNAL_GROUP_EXIT while sending SIGKILL to
the thread group.  This means that a TASK_TRACED task

	1. Will be awakened by signal_wake_up(1)

	2. Can't sleep again via ptrace_notify()

	3. Can't go to do_signal_stop() after return
	   from ptrace_stop() in get_signal_to_deliver()

So we can remove all ptrace related stuff from coredump path.

Signed-off-by: Oleg Nesterov <oleg@tv-sign.ru>
Cc: "Eric W. Biederman" <ebiederm@xmission.com>
Cc: Roland McGrath <roland@redhat.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>

1 files changed, 2 insertions, 1 deletions

diff --git a/kernel/ptrace.c b/kernel/ptrace.c
index 6252d2fa2bf3..335c5b932e14 100644
--- a/kernel/ptrace.c
+++ b/kernel/ptrace.c
@@ -214,7 +214,7 @@ out:
         return retval;
 }
 
-void __ptrace_detach(struct task_struct *child, unsigned int data)
+static inline void __ptrace_detach(struct task_struct *child, unsigned int data)
 {
         child->exit_code = data;
         /* .. re-parent .. */
@@ -233,6 +233,7 @@ int ptrace_detach(struct task_struct *child, unsigned int data)
         ptrace_disable(child);
 
         write_lock_irq(&tasklist_lock);
+        /* protect against de_thread()->release_task() */
         if (child->ptrace)
                 __ptrace_detach(child, data);
         write_unlock_irq(&tasklist_lock);