From e46787f0dd9385449fd77246d4fddb8634350af8 Mon Sep 17 00:00:00 2001 From: Florian Westphal Date: Mon, 21 Dec 2015 21:29:25 +0100 Subject: [PATCH] tcp: send_reset: test for non-NULL sk first tcp_md5_do_lookup requires a full socket, so once we extend _send_reset() to also accept timewait socket we would have to change if (!sk && hash_location) to something like if ((!sk || !sk_fullsock(sk)) && hash_location) { ... } else { (sk && sk_fullsock(sk)) tcp_md5_do_lookup() } Switch the two branches: check if we have a socket first, then fall back to a listener lookup if we saw a md5 option (hash_location). Signed-off-by: Florian Westphal Acked-by: Eric Dumazet Acked-by: Hannes Frederic Sowa Signed-off-by: David S. Miller --- net/ipv4/tcp_ipv4.c | 11 +++++------ net/ipv6/tcp_ipv6.c | 6 +++--- 2 files changed, 8 insertions(+), 9 deletions(-) diff --git a/net/ipv4/tcp_ipv4.c b/net/ipv4/tcp_ipv4.c index 46e92fbd26a8..eb29c2f5bcea 100644 --- a/net/ipv4/tcp_ipv4.c +++ b/net/ipv4/tcp_ipv4.c @@ -587,7 +587,7 @@ static void tcp_v4_send_reset(const struct sock *sk, struct sk_buff *skb) } rep; struct ip_reply_arg arg; #ifdef CONFIG_TCP_MD5SIG - struct tcp_md5sig_key *key; + struct tcp_md5sig_key *key = NULL; const __u8 *hash_location = NULL; unsigned char newhash[16]; int genhash; @@ -627,7 +627,10 @@ static void tcp_v4_send_reset(const struct sock *sk, struct sk_buff *skb) net = sk ? sock_net(sk) : dev_net(skb_dst(skb)->dev); #ifdef CONFIG_TCP_MD5SIG hash_location = tcp_parse_md5sig_option(th); - if (!sk && hash_location) { + if (sk) { + key = tcp_md5_do_lookup(sk, (union tcp_md5_addr *) + &ip_hdr(skb)->saddr, AF_INET); + } else if (hash_location) { /* * active side is lost. Try to find listening socket through * source port, and then find md5 key through listening socket. @@ -651,10 +654,6 @@ static void tcp_v4_send_reset(const struct sock *sk, struct sk_buff *skb) genhash = tcp_v4_md5_hash_skb(newhash, key, NULL, skb); if (genhash || memcmp(hash_location, newhash, 16) != 0) goto release_sk1; - } else { - key = sk ? tcp_md5_do_lookup(sk, (union tcp_md5_addr *) - &ip_hdr(skb)->saddr, - AF_INET) : NULL; } if (key) { diff --git a/net/ipv6/tcp_ipv6.c b/net/ipv6/tcp_ipv6.c index f03d2b0445fd..32fa0de9982a 100644 --- a/net/ipv6/tcp_ipv6.c +++ b/net/ipv6/tcp_ipv6.c @@ -854,7 +854,9 @@ static void tcp_v6_send_reset(const struct sock *sk, struct sk_buff *skb) #ifdef CONFIG_TCP_MD5SIG hash_location = tcp_parse_md5sig_option(th); - if (!sk && hash_location) { + if (sk) { + key = tcp_v6_md5_do_lookup(sk, &ipv6h->saddr); + } else if (hash_location) { /* * active side is lost. Try to find listening socket through * source port, and then find md5 key through listening socket. @@ -877,8 +879,6 @@ static void tcp_v6_send_reset(const struct sock *sk, struct sk_buff *skb) genhash = tcp_v6_md5_hash_skb(newhash, key, NULL, skb); if (genhash || memcmp(hash_location, newhash, 16) != 0) goto release_sk1; - } else { - key = sk ? tcp_v6_md5_do_lookup(sk, &ipv6h->saddr) : NULL; } #endif -- 2.39.5