The patch titled
     ptrace_stop: fix the race with ptrace detach+attach
has been removed from the -mm tree.  Its filename was
     ptrace_stop-fix-the-race-with-ptrace-detachattach.patch

This patch was dropped because it was merged into mainline or a subsystem tree

The current -mm tree may be found at http://userweb.kernel.org/~akpm/mmotm/

------------------------------------------------------
Subject: ptrace_stop: fix the race with ptrace detach+attach
From: Oleg Nesterov <[EMAIL PROTECTED]>

If the tracer went away (may_ptrace_stop() failed), ptrace_stop() drops
tasklist and then changes the ->state from TASK_TRACED to TASK_RUNNING.

This can fool another tracer which attaches to us in between.  Change the
->state under tasklist_lock to ensure that ptrace_check_attach() can't wrongly
succeed.  Also, remove the unnecessary mb().

Signed-off-by: Oleg Nesterov <[EMAIL PROTECTED]>
Acked-by: Roland Dreier <[EMAIL PROTECTED]>
Signed-off-by: Andrew Morton <[EMAIL PROTECTED]>
---

 kernel/signal.c |    6 +++---
 1 file changed, 3 insertions(+), 3 deletions(-)

diff -puN kernel/signal.c~ptrace_stop-fix-the-race-with-ptrace-detachattach 
kernel/signal.c
--- a/kernel/signal.c~ptrace_stop-fix-the-race-with-ptrace-detachattach
+++ a/kernel/signal.c
@@ -1638,11 +1638,11 @@ static void ptrace_stop(int exit_code, i
        } else {
                /*
                 * By the time we got the lock, our tracer went away.
-                * Don't stop here.
+                * Don't drop the lock yet, another tracer may come.
                 */
-               read_unlock(&tasklist_lock);
-               set_current_state(TASK_RUNNING);
+               __set_current_state(TASK_RUNNING);
                current->exit_code = nostop_code;
+               read_unlock(&tasklist_lock);
        }
 
        /*
_

Patches currently in -mm which might be from [EMAIL PROTECTED] are

origin.patch
revert-proc-fix-the-threaded-proc-self.patch
procfs-task-exe-symlink.patch
procfs-task-exe-symlink-fix.patch

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