[PATCH v2] vxlan: fix a potential issue when create a new vxlan fdb entry.

From: Haishuang Yan
Date: Mon Nov 28 2016 - 21:00:03 EST


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

Signed-off-by: Haishuang Yan <yanhaishuang@xxxxxxxxxxxxxxxxxxxx>

Changes in v2:
- Unnecessary to initialize rc to zero.
---
drivers/net/vxlan.c | 10 +++++++---
1 file changed, 7 insertions(+), 3 deletions(-)

diff --git a/drivers/net/vxlan.c b/drivers/net/vxlan.c
index 21e92be..bb70dd5 100644
--- 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,
--
1.8.3.1