2.6.35-longterm review patch. If anyone has any objections, please let me know.
------------------ From: David S. Miller <[email protected]> [ Upstream commit 8f49c2703b33519aaaccc63f571b465b9d2b3a2d ] Alexey Kuznetsov noticed a regression introduced by commit f1ecd5d9e7366609d640ff4040304ea197fbc618 ("Revert Backoff [v3]: Revert RTO on ICMP destination unreachable") The RTO and timer modification code added to tcp_v4_err() doesn't check sock_owned_by_user(), which if true means we don't have exclusive access to the socket and therefore cannot modify it's critical state. Just skip this new code block if sock_owned_by_user() is true and eliminate the now superfluous sock_owned_by_user() code block contained within. Reported-by: Alexey Kuznetsov <[email protected]> Signed-off-by: David S. Miller <[email protected]> Signed-off-by: Andi Kleen <[email protected]> CC: Damian Lukowski <[email protected]> Acked-by: Eric Dumazet <[email protected]> Signed-off-by: Greg Kroah-Hartman <[email protected]> --- net/ipv4/tcp_ipv4.c | 8 +++----- 1 file changed, 3 insertions(+), 5 deletions(-) Index: linux-2.6.35.y/net/ipv4/tcp_ipv4.c =================================================================== --- linux-2.6.35.y.orig/net/ipv4/tcp_ipv4.c +++ linux-2.6.35.y/net/ipv4/tcp_ipv4.c @@ -411,6 +411,9 @@ void tcp_v4_err(struct sk_buff *icmp_skb !icsk->icsk_backoff) break; + if (sock_owned_by_user(sk)) + break; + icsk->icsk_backoff--; inet_csk(sk)->icsk_rto = __tcp_set_rto(tp) << icsk->icsk_backoff; @@ -425,11 +428,6 @@ void tcp_v4_err(struct sk_buff *icmp_skb if (remaining) { inet_csk_reset_xmit_timer(sk, ICSK_TIME_RETRANS, remaining, TCP_RTO_MAX); - } else if (sock_owned_by_user(sk)) { - /* RTO revert clocked out retransmission, - * but socket is locked. Will defer. */ - inet_csk_reset_xmit_timer(sk, ICSK_TIME_RETRANS, - HZ/20, TCP_RTO_MAX); } else { /* RTO revert clocked out retransmission. * Will retransmit now */ _______________________________________________ stable mailing list [email protected] http://linux.kernel.org/mailman/listinfo/stable
