net: bridge: don't cache ether dest pointer on input

We would cache ether dst pointer on input in br_handle_frame_finish but
after the neigh suppress code that could lead to a stale pointer since
both ipv4 and ipv6 suppress code do pskb_may_pull. This means we have to
always reload it after the suppress code so there's no point in having
it cached just retrieve it directly.

Fixes: 057658cb33 ("bridge: suppress arp pkts on BR_NEIGH_SUPPRESS ports")
Fixes: ed842faeb2 ("bridge: suppress nd pkts on BR_NEIGH_SUPPRESS ports")
Signed-off-by: Nikolay Aleksandrov <nikolay@cumulusnetworks.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
This commit is contained in:
Nikolay Aleksandrov 2019-07-02 15:00:20 +03:00 committed by David S. Miller
parent 3b26a5d03d
commit 3d26eb8ad1

View File

@ -74,7 +74,6 @@ int br_handle_frame_finish(struct net *net, struct sock *sk, struct sk_buff *skb
struct net_bridge_fdb_entry *dst = NULL;
struct net_bridge_mdb_entry *mdst;
bool local_rcv, mcast_hit = false;
const unsigned char *dest;
struct net_bridge *br;
u16 vid = 0;
@ -92,10 +91,9 @@ int br_handle_frame_finish(struct net *net, struct sock *sk, struct sk_buff *skb
br_fdb_update(br, p, eth_hdr(skb)->h_source, vid, false);
local_rcv = !!(br->dev->flags & IFF_PROMISC);
dest = eth_hdr(skb)->h_dest;
if (is_multicast_ether_addr(dest)) {
if (is_multicast_ether_addr(eth_hdr(skb)->h_dest)) {
/* by definition the broadcast is also a multicast address */
if (is_broadcast_ether_addr(dest)) {
if (is_broadcast_ether_addr(eth_hdr(skb)->h_dest)) {
pkt_type = BR_PKT_BROADCAST;
local_rcv = true;
} else {
@ -145,7 +143,7 @@ int br_handle_frame_finish(struct net *net, struct sock *sk, struct sk_buff *skb
}
break;
case BR_PKT_UNICAST:
dst = br_fdb_find_rcu(br, dest, vid);
dst = br_fdb_find_rcu(br, eth_hdr(skb)->h_dest, vid);
default:
break;
}