[PATCH 3.16 027/328] vxlan: fix a potential issue when create a new vxlan fdb entry.

[Ben Hutchings]

3.16.62-rc1 review patch.  If anyone has any objections, please let me know.

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

From: Haishuang Yan <yanhaishu...@cmss.chinamobile.com>

commit 17b463654f41f0aa334efd5a6efeab8a6e9496f7 upstream.

vxlan_fdb_append may return error, so add the proper check,
otherwise it will cause memory leak.

Signed-off-by: Haishuang Yan <yanhaishu...@cmss.chinamobile.com>

Changes in v2:
  - Unnecessary to initialize rc to zero.
Acked-by: Jiri Benc <jb...@redhat.com>
Signed-off-by: David S. Miller <da...@davemloft.net>
Signed-off-by: Ben Hutchings <b...@decadent.org.uk>
---
 drivers/net/vxlan.c | 10 +++++++---
 1 file changed, 7 insertions(+), 3 deletions(-)

--- a/drivers/net/vxlan.c
+++ b/drivers/net/vxlan.c
@@ -695,6 +695,7 @@ static int vxlan_fdb_create(struct vxlan
        struct vxlan_rdst *rd = NULL;
        struct vxlan_fdb *f;
        int notify = 0;
+       int rc;
 
        f = __vxlan_find_mac(vxlan, mac);
        if (f) {
@@ -729,8 +730,7 @@ static int vxlan_fdb_create(struct vxlan
                if ((flags & NLM_F_APPEND) &&
                    (is_multicast_ether_addr(f->eth_addr) ||
                     is_zero_ether_addr(f->eth_addr))) {
-                       int rc = vxlan_fdb_append(f, ip, port, vni, ifindex,
-                                                 &rd);
+                       rc = vxlan_fdb_append(f, ip, port, vni, ifindex, &rd);
 
                        if (rc < 0)
                                return rc;
@@ -760,7 +760,11 @@ static int vxlan_fdb_create(struct vxlan
                INIT_LIST_HEAD(&f->remotes);
                memcpy(f->eth_addr, mac, ETH_ALEN);
 
-               vxlan_fdb_append(f, ip, port, vni, ifindex, &rd);
+               rc = vxlan_fdb_append(f, ip, port, vni, ifindex, &rd);
+               if (rc < 0) {
+                       kfree(f);
+                       return rc;
+               }
 
                ++vxlan->addrcnt;
                hlist_add_head_rcu(&f->hlist,