path: root/net/ipv4/tcp_metrics.c
diff options
authorEric Dumazet <edumazet@google.com>2013-11-13 15:00:46 -0800
committerDavid S. Miller <davem@davemloft.net>2013-11-14 16:33:18 -0500
commitdccf76ca6b626c0c4a4e09bb221adee3270ab0ef (patch)
tree655cb86c3c54d9b5ac9cb05f632bf0cd16077a4a /net/ipv4/tcp_metrics.c
parentb869ccfab1e324507fa3596e3e1308444fb68227 (diff)
net-tcp: fix panic in tcp_fastopen_cache_set()
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 <edumazet@google.com> Reported-by: Dave Jones <davej@redhat.com> Cc: Yuchung Cheng <ycheng@google.com> Acked-by: Yuchung Cheng <ycheng@google.com> Tested-by: Dave Jones <davej@fedoraproject.org> Signed-off-by: David S. Miller <davem@davemloft.net>
Diffstat (limited to 'net/ipv4/tcp_metrics.c')
1 files changed, 4 insertions, 1 deletions
diff --git a/net/ipv4/tcp_metrics.c b/net/ipv4/tcp_metrics.c
index 2ab09cbae74d..d3ee2e0c28b6 100644
--- a/net/ipv4/tcp_metrics.c
+++ b/net/ipv4/tcp_metrics.c
@@ -663,10 +663,13 @@ 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;
- 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;