Commit 4fab9071 authored by Neal Cardwell's avatar Neal Cardwell Committed by David S. Miller
Browse files

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: default avatarNeal Cardwell <ncardwell@google.com>
Signed-off-by: default avatarEric Dumazet <edumazet@google.com>
Diagnosed-by: default avatarWillem de Bruijn <willemb@google.com>
Fixes: 563d34d0 ("tcp: dont drop MTU reduction indications")
Reviewed-by: default avatarHannes Frederic Sowa <hannes@stressinduktion.org>
Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
parent bc8fc7b8

include/net/inet_connection_sock.h

+1 −0
Original line number Diff line number Diff line
@@ -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

include/net/sock.h

+0 −1
Original line number Diff line number Diff line
@@ -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);

include/net/tcp.h

+1 −0
Original line number Diff line number Diff line
@@ -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,

net/ipv4/tcp_ipv4.c

+3 −2
Original line number Diff line number Diff line
@@ -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,

net/ipv4/tcp_output.c

+1 −1
Original line number Diff line number Diff line
@@ -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);

	}

}

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