lkml.org 
[lkml]   [2012]   [Nov]   [2]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
Patch in this message
/
From
Subject[ 10/24] libceph: avoid NULL kref_put when osd reset races with alloc_msg
Date
3.6-stable review patch.  If anyone has any objections, please let me know.

------------------

From: Sage Weil <sage@inktank.com>

commit 9bd952615a42d7e2ce3fa2c632e808e804637a1a upstream.

The ceph_on_in_msg_alloc() method drops con->mutex while it allocates a
message. If that races with a timeout that resends a zillion messages and
resets the connection, and the ->alloc_msg() method returns a NULL message,
it will call ceph_msg_put(NULL) and BUG.

Fix by only calling put if msg is non-NULL.

Fixes http://tracker.newdream.net/issues/3142

Signed-off-by: Sage Weil <sage@inktank.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

---
net/ceph/messenger.c | 3 ++-
1 file changed, 2 insertions(+), 1 deletion(-)

--- a/net/ceph/messenger.c
+++ b/net/ceph/messenger.c
@@ -2750,7 +2750,8 @@ static int ceph_con_in_msg_alloc(struct
msg = con->ops->alloc_msg(con, hdr, skip);
mutex_lock(&con->mutex);
if (con->state != CON_STATE_OPEN) {
- ceph_msg_put(msg);
+ if (msg)
+ ceph_msg_put(msg);
return -EAGAIN;
}
con->in_msg = msg;



\
 
 \ /
  Last update: 2012-11-02 20:01    [W:1.460 / U:0.080 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site