From: Dan Carpenter <dan.carpenter@oracle.com>
Date: Thu, 15 Aug 2013 05:52:48 +0000 (+0300)
Subject: libceph: potential NULL dereference in ceph_osdc_handle_map()
X-Git-Url: http://git.mmlx.us/?a=commitdiff_plain;h=53341d7de3f013cc39a3692bdfd02032ce722dff;p=linux-edison.git

libceph: potential NULL dereference in ceph_osdc_handle_map()

commit b72e19b9225d4297a18715b0998093d843d170fa upstream.

There are two places where we read "nr_maps" if both of them are set to
zero then we would hit a NULL dereference here.

Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Reviewed-by: Sage Weil <sage@inktank.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---

diff --git a/net/ceph/osd_client.c b/net/ceph/osd_client.c
index 65d8c3b7df9..311161eac5c 100644
--- a/net/ceph/osd_client.c
+++ b/net/ceph/osd_client.c
@@ -1786,6 +1786,8 @@ void ceph_osdc_handle_map(struct ceph_osd_client *osdc, struct ceph_msg *msg)
 		nr_maps--;
 	}
 
+	if (!osdc->osdmap)
+		goto bad;
 done:
 	downgrade_write(&osdc->map_sem);
 	ceph_monc_got_osdmap(&osdc->client->monc, osdc->osdmap->epoch);