From 4ca60d08cbe65f501baad64af50fceba79c19fbb Mon Sep 17 00:00:00 2001 From: Florian Westphal Date: Thu, 9 Mar 2017 23:22:30 +0100 Subject: netfilter: bridge: honor frag_max_size when refragmenting consider a bridge with mtu 9000, but end host sending smaller packets to another host with mtu < 9000. In this case, after reassembly, bridge+defrag would refragment, and then attempt to send the reassembled packet as long as it was below 9k. Instead we have to cap by the largest fragment size seen. Signed-off-by: Florian Westphal Signed-off-by: Pablo Neira Ayuso --- net/bridge/br_netfilter_hooks.c | 12 +++++++----- 1 file changed, 7 insertions(+), 5 deletions(-) (limited to 'net/bridge') diff --git a/net/bridge/br_netfilter_hooks.c b/net/bridge/br_netfilter_hooks.c index 95087e6e8258..3c5185021c1c 100644 --- a/net/bridge/br_netfilter_hooks.c +++ b/net/bridge/br_netfilter_hooks.c @@ -721,18 +721,20 @@ static unsigned int nf_bridge_mtu_reduction(const struct sk_buff *skb) static int br_nf_dev_queue_xmit(struct net *net, struct sock *sk, struct sk_buff *skb) { - struct nf_bridge_info *nf_bridge; - unsigned int mtu_reserved; + struct nf_bridge_info *nf_bridge = nf_bridge_info_get(skb); + unsigned int mtu, mtu_reserved; mtu_reserved = nf_bridge_mtu_reduction(skb); + mtu = skb->dev->mtu; + + if (nf_bridge->frag_max_size && nf_bridge->frag_max_size < mtu) + mtu = nf_bridge->frag_max_size; - if (skb_is_gso(skb) || skb->len + mtu_reserved <= skb->dev->mtu) { + if (skb_is_gso(skb) || skb->len + mtu_reserved <= mtu) { nf_bridge_info_free(skb); return br_dev_queue_push_xmit(net, sk, skb); } - nf_bridge = nf_bridge_info_get(skb); - /* This is wrong! We should preserve the original fragment * boundaries by preserving frag_list rather than refragmenting. */ -- cgit v1.2.3 From d12c917691b45d9dffcfe7c2362d25caa40905fd Mon Sep 17 00:00:00 2001 From: WANG Cong Date: Thu, 16 Mar 2017 10:32:42 -0700 Subject: bridge: resolve a false alarm of lockdep Andrei reported a false alarm of lockdep at net/bridge/br_fdb.c:109, this is because in Andrei's case, a spin_bug() was already triggered before this, therefore the debug_locks is turned off, lockdep_is_held() is no longer accurate after that. We should use lockdep_assert_held_once() instead of lockdep_is_held() to respect debug_locks. Fixes: 410b3d48f5111 ("bridge: fdb: add proper lock checks in searching functions") Reported-by: Andrei Vagin Signed-off-by: Cong Wang Acked-by: Nikolay Aleksandrov Signed-off-by: David S. Miller --- net/bridge/br_fdb.c | 2 +- net/bridge/br_private.h | 9 --------- 2 files changed, 1 insertion(+), 10 deletions(-) (limited to 'net/bridge') diff --git a/net/bridge/br_fdb.c b/net/bridge/br_fdb.c index 4f598dc2d916..6e08b7199dd7 100644 --- a/net/bridge/br_fdb.c +++ b/net/bridge/br_fdb.c @@ -106,7 +106,7 @@ static struct net_bridge_fdb_entry *br_fdb_find(struct net_bridge *br, struct hlist_head *head = &br->hash[br_mac_hash(addr, vid)]; struct net_bridge_fdb_entry *fdb; - WARN_ON_ONCE(!br_hash_lock_held(br)); + lockdep_assert_held_once(&br->hash_lock); rcu_read_lock(); fdb = fdb_find_rcu(head, addr, vid); diff --git a/net/bridge/br_private.h b/net/bridge/br_private.h index 2288fca7756c..61368186edea 100644 --- a/net/bridge/br_private.h +++ b/net/bridge/br_private.h @@ -531,15 +531,6 @@ int br_fdb_external_learn_add(struct net_bridge *br, struct net_bridge_port *p, int br_fdb_external_learn_del(struct net_bridge *br, struct net_bridge_port *p, const unsigned char *addr, u16 vid); -static inline bool br_hash_lock_held(struct net_bridge *br) -{ -#ifdef CONFIG_LOCKDEP - return lockdep_is_held(&br->hash_lock); -#else - return true; -#endif -} - /* br_forward.c */ enum br_pkt_type { BR_PKT_UNICAST, -- cgit v1.2.3