Commit b4fb05ea authored Mar 07, 2012 by Eric Dumazet Committed by David S. Miller Mar 07, 2012

tcp: md5: correct a RCU lockdep splat



commit a8afca03 (tcp: md5: protects md5sig_info with RCU) added a
lockdep splat in tcp_md5_do_lookup() in case a timer fires a tcp
retransmit.

At this point, socket lock is owned by the sofirq handler, not the user,
so we should adjust a bit the lockdep condition, as we dont hold
rcu_read_lock().

Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com>
Reported-by: Valdis Kletnieks <valdis.kletnieks@vt.edu>
Signed-off-by: David S. Miller <davem@davemloft.net>

parent ae5d3372

net/ipv4/tcp_ipv4.c

+2 −1

Original line number	Diff line number	Diff line
		@@ -927,7 +927,8 @@ struct tcp_md5sig_key tcp_md5_do_lookup(struct sock sk,

		/* caller either holds rcu_read_lock() or socket lock */
		md5sig = rcu_dereference_check(tp->md5sig_info,
		sock_owned_by_user(sk));
		sock_owned_by_user(sk) \|\|
		lockdep_is_held(&sk->sk_lock.slock));
		if (!md5sig)
		return NULL;
		#if IS_ENABLED(CONFIG_IPV6)

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