From 4fab9071950c2021d846e18351e0f46a1cffd67b Mon Sep 17 00:00:00 2001 From: Neal Cardwell Date: Thu, 14 Aug 2014 12:40:05 -0400 Subject: [PATCH] tcp: fix tcp_release_cb() to dispatch via address family for mtu_reduced() Make sure we use the correct address-family-specific function for handling MTU reductions from within tcp_release_cb(). Previously AF_INET6 sockets were incorrectly always using the IPv6 code path when sometimes they were handling IPv4 traffic and thus had an IPv4 dst. Signed-off-by: Neal Cardwell Signed-off-by: Eric Dumazet Diagnosed-by: Willem de Bruijn Fixes: 563d34d057862 ("tcp: dont drop MTU reduction indications") Reviewed-by: Hannes Frederic Sowa Signed-off-by: David S. Miller --- include/net/inet_connection_sock.h | 1 + include/net/sock.h | 1 - include/net/tcp.h | 1 + net/ipv4/tcp_ipv4.c | 5 +++-- net/ipv4/tcp_output.c | 2 +- net/ipv6/tcp_ipv6.c | 3 ++- 6 files changed, 8 insertions(+), 5 deletions(-) diff --git a/include/net/inet_connection_sock.h b/include/net/inet_connection_sock.h index 7a43138..5fbe656 100644 --- a/include/net/inet_connection_sock.h +++ b/include/net/inet_connection_sock.h @@ -62,6 +62,7 @@ struct inet_connection_sock_af_ops { void (*addr2sockaddr)(struct sock *sk, struct sockaddr *); int (*bind_conflict)(const struct sock *sk, const struct inet_bind_bucket *tb, bool relax); + void (*mtu_reduced)(struct sock *sk); }; /** inet_connection_sock - INET connection oriented sock diff --git a/include/net/sock.h b/include/net/sock.h index 38805fa..7f2ab72 100644 --- a/include/net/sock.h +++ b/include/net/sock.h @@ -987,7 +987,6 @@ struct proto { struct sk_buff *skb); void (*release_cb)(struct sock *sk); - void (*mtu_reduced)(struct sock *sk); /* Keeping track of sk's, looking them up, and port selection methods. */ void (*hash)(struct sock *sk); diff --git a/include/net/tcp.h b/include/net/tcp.h index 36f5525..e337e05 100644 --- a/include/net/tcp.h +++ b/include/net/tcp.h @@ -448,6 +448,7 @@ const u8 *tcp_parse_md5sig_option(const struct tcphdr *th); */ void tcp_v4_send_check(struct sock *sk, struct sk_buff *skb); +void tcp_v4_mtu_reduced(struct sock *sk); int tcp_v4_conn_request(struct sock *sk, struct sk_buff *skb); struct sock *tcp_create_openreq_child(struct sock *sk, struct request_sock *req, diff --git a/net/ipv4/tcp_ipv4.c b/net/ipv4/tcp_ipv4.c index dceff5f..cd17f00 100644 --- a/net/ipv4/tcp_ipv4.c +++ b/net/ipv4/tcp_ipv4.c @@ -271,7 +271,7 @@ EXPORT_SYMBOL(tcp_v4_connect); * It can be called through tcp_release_cb() if socket was owned by user * at the time tcp_v4_err() was called to handle ICMP message. */ -static void tcp_v4_mtu_reduced(struct sock *sk) +void tcp_v4_mtu_reduced(struct sock *sk) { struct dst_entry *dst; struct inet_sock *inet = inet_sk(sk); @@ -302,6 +302,7 @@ static void tcp_v4_mtu_reduced(struct sock *sk) tcp_simple_retransmit(sk); } /* else let the usual retransmit timer handle it */ } +EXPORT_SYMBOL(tcp_v4_mtu_reduced); static void do_redirect(struct sk_buff *skb, struct sock *sk) { @@ -1787,6 +1788,7 @@ const struct inet_connection_sock_af_ops ipv4_specific = { .compat_setsockopt = compat_ip_setsockopt, .compat_getsockopt = compat_ip_getsockopt, #endif + .mtu_reduced = tcp_v4_mtu_reduced, }; EXPORT_SYMBOL(ipv4_specific); @@ -2406,7 +2408,6 @@ struct proto tcp_prot = { .sendpage = tcp_sendpage, .backlog_rcv = tcp_v4_do_rcv, .release_cb = tcp_release_cb, - .mtu_reduced = tcp_v4_mtu_reduced, .hash = inet_hash, .unhash = inet_unhash, .get_port = inet_csk_get_port, diff --git a/net/ipv4/tcp_output.c b/net/ipv4/tcp_output.c index ff3f0f7..5a7c41f 100644 --- a/net/ipv4/tcp_output.c +++ b/net/ipv4/tcp_output.c @@ -800,7 +800,7 @@ void tcp_release_cb(struct sock *sk) __sock_put(sk); } if (flags & (1UL << TCP_MTU_REDUCED_DEFERRED)) { - sk->sk_prot->mtu_reduced(sk); + inet_csk(sk)->icsk_af_ops->mtu_reduced(sk); __sock_put(sk); } } diff --git a/net/ipv6/tcp_ipv6.c b/net/ipv6/tcp_ipv6.c index f2ce955..29964c3 100644 --- a/net/ipv6/tcp_ipv6.c +++ b/net/ipv6/tcp_ipv6.c @@ -1595,6 +1595,7 @@ static const struct inet_connection_sock_af_ops ipv6_specific = { .compat_setsockopt = compat_ipv6_setsockopt, .compat_getsockopt = compat_ipv6_getsockopt, #endif + .mtu_reduced = tcp_v6_mtu_reduced, }; #ifdef CONFIG_TCP_MD5SIG @@ -1625,6 +1626,7 @@ static const struct inet_connection_sock_af_ops ipv6_mapped = { .compat_setsockopt = compat_ipv6_setsockopt, .compat_getsockopt = compat_ipv6_getsockopt, #endif + .mtu_reduced = tcp_v4_mtu_reduced, }; #ifdef CONFIG_TCP_MD5SIG @@ -1864,7 +1866,6 @@ struct proto tcpv6_prot = { .sendpage = tcp_sendpage, .backlog_rcv = tcp_v6_do_rcv, .release_cb = tcp_release_cb, - .mtu_reduced = tcp_v6_mtu_reduced, .hash = tcp_v6_hash, .unhash = inet_unhash, .get_port = inet_csk_get_port, -- 2.7.4