vxlan: fix a potential issue when create a new vxlan fdb entry.

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

Signed-off-by: Haishuang Yan <yanhaishuang@cmss.chinamobile.com>
Changes in v2:
  - Unnecessary to initialize rc to zero.
Acked-by: Jiri Benc <jbenc@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

diff --git a/drivers/net/vxlan.c b/drivers/net/vxlan.c
index 24532cd..2ba01ca 100644 (file)
--- a/drivers/net/vxlan.c
+++ b/drivers/net/vxlan.c
@@ -611,6 +611,7 @@ static int vxlan_fdb_create(struct vxlan_dev *vxlan,
        struct vxlan_rdst *rd = NULL;
        struct vxlan_fdb *f;
        int notify = 0;
+       int rc;
 
        f = __vxlan_find_mac(vxlan, mac);
        if (f) {
@@ -641,8 +642,7 @@ static int vxlan_fdb_create(struct vxlan_dev *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;
@@ -673,7 +673,11 @@ static int vxlan_fdb_create(struct vxlan_dev *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,