diff options
| author | Rick Jones <rick.jones2@hp.com> | 2014-11-06 10:37:54 -0800 |
|---|---|---|
| committer | David S. Miller <davem@davemloft.net> | 2014-11-07 15:45:50 -0500 |
| commit | 36cbb2452cbafca64dcdd3578047433787900cf0 (patch) | |
| tree | 3e50381574c3850fc2a6c76a14777daa821f85a0 /net/ipv6/udp.c | |
| parent | f46ad73ac6965f71d1a2ba217c4eb5b644e62949 (diff) | |
| download | linux-36cbb2452cbafca64dcdd3578047433787900cf0.tar.bz2 | |
udp: Increment UDP_MIB_IGNOREDMULTI for arriving unmatched multicasts
As NIC multicast filtering isn't perfect, and some platforms are
quite content to spew broadcasts, we should not trigger an event
for skb:kfree_skb when we do not have a match for such an incoming
datagram. We do though want to avoid sweeping the matter under the
rug entirely, so increment a suitable statistic.
This incorporates feedback from David L. Stevens, Karl Neiss and Eric
Dumazet.
V3 - use bool per David Miller
Signed-off-by: Rick Jones <rick.jones2@hp.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Diffstat (limited to 'net/ipv6/udp.c')
| -rw-r--r-- | net/ipv6/udp.c | 11 |
1 files changed, 8 insertions, 3 deletions
diff --git a/net/ipv6/udp.c b/net/ipv6/udp.c index 9b6809232b17..b756355e9739 100644 --- a/net/ipv6/udp.c +++ b/net/ipv6/udp.c @@ -771,7 +771,7 @@ static void udp6_csum_zero_error(struct sk_buff *skb) */ static int __udp6_lib_mcast_deliver(struct net *net, struct sk_buff *skb, const struct in6_addr *saddr, const struct in6_addr *daddr, - struct udp_table *udptable) + struct udp_table *udptable, int proto) { struct sock *sk, *stack[256 / sizeof(struct sock *)]; const struct udphdr *uh = udp_hdr(skb); @@ -781,6 +781,7 @@ static int __udp6_lib_mcast_deliver(struct net *net, struct sk_buff *skb, int dif = inet6_iif(skb); unsigned int count = 0, offset = offsetof(typeof(*sk), sk_nulls_node); unsigned int hash2 = 0, hash2_any = 0, use_hash2 = (hslot->count > 10); + bool inner_flushed = false; if (use_hash2) { hash2_any = udp6_portaddr_hash(net, &in6addr_any, hnum) & @@ -803,6 +804,7 @@ start_lookup: (uh->check || udp_sk(sk)->no_check6_rx)) { if (unlikely(count == ARRAY_SIZE(stack))) { flush_stack(stack, count, skb, ~0); + inner_flushed = true; count = 0; } stack[count++] = sk; @@ -821,7 +823,10 @@ start_lookup: if (count) { flush_stack(stack, count, skb, count - 1); } else { - kfree_skb(skb); + if (!inner_flushed) + UDP_INC_STATS_BH(net, UDP_MIB_IGNOREDMULTI, + proto == IPPROTO_UDPLITE); + consume_skb(skb); } return 0; } @@ -873,7 +878,7 @@ int __udp6_lib_rcv(struct sk_buff *skb, struct udp_table *udptable, */ if (ipv6_addr_is_multicast(daddr)) return __udp6_lib_mcast_deliver(net, skb, - saddr, daddr, udptable); + saddr, daddr, udptable, proto); /* Unicast */ |