vxlan: eliminate cached dst leak

After commit 0c1d70af92 ("net: use dst_cache for vxlan device"),
cached dst entries could be leaked when more than one remote was
present for a given vxlan_fdb entry, causing subsequent netns
operations to block indefinitely and "unregister_netdevice: waiting
for lo to become free." messages to appear in the kernel log.

Fix by properly releasing cached dst and freeing resources in this
case.

Fixes: 0c1d70af92 ("net: use dst_cache for vxlan device")
Signed-off-by: Lance Richardson <lrichard@redhat.com>
Acked-by: Paolo Abeni <pabeni@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
This commit is contained in:
Lance Richardson 2017-05-29 13:25:57 -04:00 committed by David S. Miller
parent aeb073241f
commit 35cf284556
1 changed files with 17 additions and 3 deletions

View File

@ -740,6 +740,22 @@ static void vxlan_fdb_destroy(struct vxlan_dev *vxlan, struct vxlan_fdb *f)
call_rcu(&f->rcu, vxlan_fdb_free);
}
static void vxlan_dst_free(struct rcu_head *head)
{
struct vxlan_rdst *rd = container_of(head, struct vxlan_rdst, rcu);
dst_cache_destroy(&rd->dst_cache);
kfree(rd);
}
static void vxlan_fdb_dst_destroy(struct vxlan_dev *vxlan, struct vxlan_fdb *f,
struct vxlan_rdst *rd)
{
list_del_rcu(&rd->list);
vxlan_fdb_notify(vxlan, f, rd, RTM_DELNEIGH);
call_rcu(&rd->rcu, vxlan_dst_free);
}
static int vxlan_fdb_parse(struct nlattr *tb[], struct vxlan_dev *vxlan,
union vxlan_addr *ip, __be16 *port, __be32 *src_vni,
__be32 *vni, u32 *ifindex)
@ -864,9 +880,7 @@ static int __vxlan_fdb_delete(struct vxlan_dev *vxlan,
* otherwise destroy the fdb entry
*/
if (rd && !list_is_singular(&f->remotes)) {
list_del_rcu(&rd->list);
vxlan_fdb_notify(vxlan, f, rd, RTM_DELNEIGH);
kfree_rcu(rd, rcu);
vxlan_fdb_dst_destroy(vxlan, f, rd);
goto out;
}