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| author | David S. Miller <davem@davemloft.net> | 2010-11-12 22:35:00 +0100 |
|---|---|---|
| committer | David S. Miller <davem@davemloft.net> | 2010-11-12 22:35:00 +0100 |
| commit | 8f49c2703b33519aaaccc63f571b465b9d2b3a2d (patch) | |
| tree | 3b2db10ae8642c87c7258522e06ee56910d5b420 /net | |
| parent | x25: Prevent crashing when parsing bad X.25 facilities (diff) | |
| download | linux-8f49c2703b33519aaaccc63f571b465b9d2b3a2d.tar.xz linux-8f49c2703b33519aaaccc63f571b465b9d2b3a2d.zip | |
tcp: Don't change unlocked socket state in tcp_v4_err().
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 <kuznet@ms2.inr.ac.ru>
Signed-off-by: David S. Miller <davem@davemloft.net>
CC: Damian Lukowski <damian@tvk.rwth-aachen.de>
Acked-by: Eric Dumazet <eric.dumazet@gmail.com>
Diffstat (limited to 'net')
| -rw-r--r-- | net/ipv4/tcp_ipv4.c | 8 |
1 files changed, 3 insertions, 5 deletions
diff --git a/net/ipv4/tcp_ipv4.c b/net/ipv4/tcp_ipv4.c index 8f8527d41682..69ccbc1dde9c 100644 --- a/net/ipv4/tcp_ipv4.c +++ b/net/ipv4/tcp_ipv4.c @@ -415,6 +415,9 @@ void tcp_v4_err(struct sk_buff *icmp_skb, u32 info) !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; @@ -429,11 +432,6 @@ void tcp_v4_err(struct sk_buff *icmp_skb, u32 info) 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 */ |