[3.11.y.z extended stable] Patch "bridge: Fix double free and memory leak around br_allowed_ingress" has been added to staging queue

[Luis Henriques]

This is a note to let you know that I have just added a patch titled

    bridge: Fix double free and memory leak around br_allowed_ingress

to the linux-3.11.y-queue branch of the 3.11.y.z extended stable tree 
which can be found at:

 http://kernel.ubuntu.com/git?p=ubuntu/linux.git;a=shortlog;h=refs/heads/linux-3.11.y-queue

If you, or anyone else, feels it should not be added to this tree, please 
reply to this email.

For more information about the 3.11.y.z tree, see
https://wiki.ubuntu.com/Kernel/Dev/ExtendedStable

Thanks.
-Luis

------

>From 5961f9a78371db8c8aba8bacf7d59771582ad5e1 Mon Sep 17 00:00:00 2001
From: Toshiaki Makita <makita.toshiaki at lab.ntt.co.jp>
Date: Wed, 9 Apr 2014 17:00:30 +0900
Subject: bridge: Fix double free and memory leak around br_allowed_ingress

commit eb7076182d1ae4bc4641534134ed707100d76acc upstream.

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>
Signed-off-by: David S. Miller <davem at davemloft.net>
Signed-off-by: Luis Henriques <luis.henriques at canonical.com>
---
 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 a2fd37ec35f7..c378750602cd 100644
--- a/net/bridge/br_input.c
+++ b/net/bridge/br_input.c
@@ -72,7 +72,7 @@ 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 9a9ffe7e4019..d8deb8bda736 100644
--- a/net/bridge/br_vlan.c
+++ b/net/bridge/br_vlan.c
@@ -202,7 +202,7 @@ bool br_allowed_ingress(struct net_bridge *br, struct net_port_vlans *v,
 	 * rejected.
 	 */
 	if (!v)
-		return false;
+		goto drop;

 	if (br_vlan_get_tag(skb, vid)) {
 		u16 pvid = br_get_pvid(v);
@@ -212,7 +212,7 @@ bool br_allowed_ingress(struct net_bridge *br, struct net_port_vlans *v,
 		 * traffic belongs to.
 		 */
 		if (pvid == VLAN_N_VID)
-			return false;
+			goto drop;

 		/* PVID is set on this port.  Any untagged ingress
 		 * frame is considered to belong to this vlan.
@@ -224,7 +224,8 @@ 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;
 }

--
1.9.1