coredump: fix the setting of PF_DUMPCORE

Commit 079148b919d0 ("coredump: factor out the setting of PF_DUMPCORE")
cleaned up the setting of PF_DUMPCORE by removing it from all the
linux_binfmt->core_dump() and moving it to zap_threads().But this ended
up clearing all the previously set flags.  This causes issues during
core generation when tsk->flags is checked again (eg.  for PF_USED_MATH
to dump floating point registers).  Fix this.

Signed-off-by: Silesh C V <svellattu@mvista.com>
Acked-by: Oleg Nesterov <oleg@redhat.com>
Cc: Mandeep Singh Baines <msb@chromium.org>
Cc: <stable@vger.kernel.org>	[3.10+]
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

1 files changed, 1 insertions, 1 deletions

diff --git a/fs/coredump.c b/fs/coredump.c
index 0b2528fb640e..a93f7e6ea4cf 100644
--- a/fs/coredump.c
+++ b/fs/coredump.c
@@ -306,7 +306,7 @@ static int zap_threads(struct task_struct *tsk, struct mm_struct *mm,
         if (unlikely(nr < 0))
                 return nr;
 
-        tsk->flags = PF_DUMPCORE;
+        tsk->flags |= PF_DUMPCORE;
         if (atomic_read(&mm->mm_users) == nr + 1)
                 goto done;
         /*