Toshiaki Makita
2014-Apr-09 08:00 UTC
[Bridge] [PATCH net] bridge: Fix double free and memory leak around br_allowed_ingress
br_allowed_ingress() has two problems. 1. If br_allowed_ingress() is called by br_handle_frame_finish() and vlan_untag() in br_allowed_ingress() fails, skb will be freed by both vlan_untag() and br_handle_frame_finish(). 2. If br_allowed_ingress() is called by br_dev_xmit() and br_allowed_ingress() fails, the skb will not be freed. Fix these two problems by freeing the skb in br_allowed_ingress() if it fails. Signed-off-by: Toshiaki Makita <makita.toshiaki at lab.ntt.co.jp> --- net/bridge/br_input.c | 2 +- net/bridge/br_vlan.c | 7 ++++--- 2 files changed, 5 insertions(+), 4 deletions(-) diff --git a/net/bridge/br_input.c b/net/bridge/br_input.c index d0cca3c..7985dea 100644 --- a/net/bridge/br_input.c +++ b/net/bridge/br_input.c @@ -73,7 +73,7 @@ int br_handle_frame_finish(struct sk_buff *skb) goto drop; if (!br_allowed_ingress(p->br, nbp_get_vlan_info(p), skb, &vid)) - goto drop; + goto out; /* insert into forwarding database after filtering to avoid spoofing */ br = p->br; diff --git a/net/bridge/br_vlan.c b/net/bridge/br_vlan.c index 9151071..4a37161 100644 --- a/net/bridge/br_vlan.c +++ b/net/bridge/br_vlan.c @@ -170,7 +170,7 @@ bool br_allowed_ingress(struct net_bridge *br, struct net_port_vlans *v, * rejected. */ if (!v) - return false; + goto drop; /* If vlan tx offload is disabled on bridge device and frame was * sent from vlan device on the bridge device, it does not have @@ -193,7 +193,7 @@ bool br_allowed_ingress(struct net_bridge *br, struct net_port_vlans *v, * vlan untagged or priority-tagged traffic belongs to. */ if (pvid == VLAN_N_VID) - return false; + goto drop; /* PVID is set on this port. Any untagged or priority-tagged * ingress frame is considered to belong to this vlan. @@ -216,7 +216,8 @@ bool br_allowed_ingress(struct net_bridge *br, struct net_port_vlans *v, /* Frame had a valid vlan tag. See if vlan is allowed */ if (test_bit(*vid, v->vlan_bitmap)) return true; - +drop: + kfree_skb(skb); return false; } -- 1.8.1.2