diff options
| author | Sage Weil <sage@inktank.com> | 2012-10-25 19:49:41 +0400 |
|---|---|---|
| committer | Alex Elder <elder@inktank.com> | 2012-10-27 01:35:04 +0400 |
| commit | 7246240c7c186542f73af4fadc744d66440f616f (patch) | |
| tree | 2b6270df2edae0dcc6e7c7c3474ff9c46d841e55 /net/ceph | |
| parent | 0f9831a89310cebba52d3f526e6cc5c2e403e6f1 (diff) | |
| download | linux-7246240c7c186542f73af4fadc744d66440f616f.tar.xz | |
libceph: avoid NULL kref_put from NULL alloc_msg return
The ceph_on_in_msg_alloc() method calls the ->alloc_msg() helper which
may return NULL. It also drops con->mutex while it allocates a message,
which means that the connection state may change (e.g., get closed). If
that happens, we clean up and bail out. Avoid calling ceph_msg_put() on
a NULL return value and triggering a crash.
This was observed when an ->alloc_msg() call races with a timeout that
resends a zillion messages and resets the connection, and ->alloc_msg()
returns NULL (because the request was resent to another target).
Fixes http://tracker.newdream.net/issues/3342
Signed-off-by: Sage Weil <sage@inktank.com>
Reviewed-by: Alex Elder <elder@inktank.com>
Diffstat (limited to 'net/ceph')
| -rw-r--r-- | net/ceph/messenger.c | 3 |
1 files changed, 2 insertions, 1 deletions
diff --git a/net/ceph/messenger.c b/net/ceph/messenger.c index 66f6f56bcb23..1041114453db 100644 --- a/net/ceph/messenger.c +++ b/net/ceph/messenger.c @@ -2742,7 +2742,8 @@ static int ceph_con_in_msg_alloc(struct ceph_connection *con, int *skip) 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; |