3.8.13.15 -stable review patch. If anyone has any objections, please let me know.
------------------ From: Eric Dumazet <eduma...@google.com> [ Upstream commit dccf76ca6b626c0c4a4e09bb221adee3270ab0ef ] We had some reports of crashes using TCP fastopen, and Dave Jones gave a nice stack trace pointing to the error. Issue is that tcp_get_metrics() should not be called with a NULL dst Fixes: 1fe4c481ba637 ("net-tcp: Fast Open client - cookie cache") Signed-off-by: Eric Dumazet <eduma...@google.com> Reported-by: Dave Jones <da...@redhat.com> Cc: Yuchung Cheng <ych...@google.com> Acked-by: Yuchung Cheng <ych...@google.com> Tested-by: Dave Jones <da...@fedoraproject.org> Signed-off-by: David S. Miller <da...@davemloft.net> Signed-off-by: Kamal Mostafa <ka...@canonical.com> --- net/ipv4/tcp_metrics.c | 5 ++++- 1 file changed, 4 insertions(+), 1 deletion(-) diff --git a/net/ipv4/tcp_metrics.c b/net/ipv4/tcp_metrics.c index f696d7c..f190419 100644 --- a/net/ipv4/tcp_metrics.c +++ b/net/ipv4/tcp_metrics.c @@ -662,10 +662,13 @@ void tcp_fastopen_cache_get(struct sock *sk, u16 *mss, void tcp_fastopen_cache_set(struct sock *sk, u16 mss, struct tcp_fastopen_cookie *cookie, bool syn_lost) { + struct dst_entry *dst = __sk_dst_get(sk); struct tcp_metrics_block *tm; + if (!dst) + return; rcu_read_lock(); - tm = tcp_get_metrics(sk, __sk_dst_get(sk), true); + tm = tcp_get_metrics(sk, dst, true); if (tm) { struct tcp_fastopen_metrics *tfom = &tm->tcpm_fastopen; -- 1.8.3.2 -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/