From ce25d66ad5f8d921bac5fe2d32d62fa30c0f9a70 Mon Sep 17 00:00:00 2001 From: Eric Dumazet Date: Thu, 2 Jun 2016 14:52:43 -0700 Subject: [PATCH] Possible problem with e6afc8ac ("udp: remove headers from UDP packets before queueing") Paul Moore tracked a regression caused by a recent commit, which mistakenly assumed that sk_filter() could be avoided if socket had no current BPF filter. The intent was to avoid udp_lib_checksum_complete() overhead. But sk_filter() also checks skb_pfmemalloc() and security_sock_rcv_skb(), so better call it. Fixes: e6afc8ace6dd ("udp: remove headers from UDP packets before queueing") Signed-off-by: Eric Dumazet Reported-by: Paul Moore Tested-by: Paul Moore Tested-by: Stephen Smalley Cc: samanthakumar Signed-off-by: David S. Miller --- net/ipv4/udp.c | 10 +++++----- net/ipv6/udp.c | 12 ++++++------ 2 files changed, 11 insertions(+), 11 deletions(-) diff --git a/net/ipv4/udp.c b/net/ipv4/udp.c index d56c0559b477..0ff31d97d485 100644 --- a/net/ipv4/udp.c +++ b/net/ipv4/udp.c @@ -1618,12 +1618,12 @@ int udp_queue_rcv_skb(struct sock *sk, struct sk_buff *skb) } } - if (rcu_access_pointer(sk->sk_filter)) { - if (udp_lib_checksum_complete(skb)) + if (rcu_access_pointer(sk->sk_filter) && + udp_lib_checksum_complete(skb)) goto csum_error; - if (sk_filter(sk, skb)) - goto drop; - } + + if (sk_filter(sk, skb)) + goto drop; udp_csum_pull_header(skb); if (sk_rcvqueues_full(sk, sk->sk_rcvbuf)) { diff --git a/net/ipv6/udp.c b/net/ipv6/udp.c index 2da1896af934..f421c9f23c5b 100644 --- a/net/ipv6/udp.c +++ b/net/ipv6/udp.c @@ -653,12 +653,12 @@ int udpv6_queue_rcv_skb(struct sock *sk, struct sk_buff *skb) } } - if (rcu_access_pointer(sk->sk_filter)) { - if (udp_lib_checksum_complete(skb)) - goto csum_error; - if (sk_filter(sk, skb)) - goto drop; - } + if (rcu_access_pointer(sk->sk_filter) && + udp_lib_checksum_complete(skb)) + goto csum_error; + + if (sk_filter(sk, skb)) + goto drop; udp_csum_pull_header(skb); if (sk_rcvqueues_full(sk, sk->sk_rcvbuf)) { -- 2.20.1