summaryrefslogtreecommitdiff
path: root/net/ipv4/tcp_input.c
diff options
context:
space:
mode:
authorGuillaume Nault <gnault@redhat.com>2019-03-08 22:09:47 +0100
committerGreg Kroah-Hartman <gregkh@linuxfoundation.org>2019-03-23 08:44:30 +0100
commit191aa19ab8c1459c11a5c541801f17e01dda17de (patch)
tree28ceaef38926abd07158a92fda17597303b36b20 /net/ipv4/tcp_input.c
parentd31b540d63b19f60ae34195aab5644862ea0a683 (diff)
tcp: handle inet_csk_reqsk_queue_add() failures
[ Upstream commit 9d3e1368bb45893a75a5dfb7cd21fdebfa6b47af ] Commit 7716682cc58e ("tcp/dccp: fix another race at listener dismantle") let inet_csk_reqsk_queue_add() fail, and adjusted {tcp,dccp}_check_req() accordingly. However, TFO and syncookies weren't modified, thus leaking allocated resources on error. Contrary to tcp_check_req(), in both syncookies and TFO cases, we need to drop the request socket. Also, since the child socket is created with inet_csk_clone_lock(), we have to unlock it and drop an extra reference (->sk_refcount is initially set to 2 and inet_csk_reqsk_queue_add() drops only one ref). For TFO, we also need to revert the work done by tcp_try_fastopen() (with reqsk_fastopen_remove()). Fixes: 7716682cc58e ("tcp/dccp: fix another race at listener dismantle") Signed-off-by: Guillaume Nault <gnault@redhat.com> Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Diffstat (limited to 'net/ipv4/tcp_input.c')
-rw-r--r--net/ipv4/tcp_input.c8
1 files changed, 7 insertions, 1 deletions
diff --git a/net/ipv4/tcp_input.c b/net/ipv4/tcp_input.c
index 1aff93d76f24..561f568e8938 100644
--- a/net/ipv4/tcp_input.c
+++ b/net/ipv4/tcp_input.c
@@ -6409,7 +6409,13 @@ int tcp_conn_request(struct request_sock_ops *rsk_ops,
af_ops->send_synack(fastopen_sk, dst, &fl, req,
&foc, false);
/* Add the child socket directly into the accept queue */
- inet_csk_reqsk_queue_add(sk, req, fastopen_sk);
+ if (!inet_csk_reqsk_queue_add(sk, req, fastopen_sk)) {
+ reqsk_fastopen_remove(fastopen_sk, req, false);
+ bh_unlock_sock(fastopen_sk);
+ sock_put(fastopen_sk);
+ reqsk_put(req);
+ goto drop;
+ }
sk->sk_data_ready(sk);
bh_unlock_sock(fastopen_sk);
sock_put(fastopen_sk);