diff options
| author | Eric Dumazet <edumazet@google.com> | 2015-11-05 11:07:13 -0800 |
|---|---|---|
| committer | David S. Miller <davem@davemloft.net> | 2015-11-05 14:36:09 -0500 |
| commit | 805c4bc05705fb2b71ec970960b456eee9900953 (patch) | |
| tree | 6e753b369a8f3663b5a50d3174b1a6fe0495714f /net/ipv6/tcp_ipv6.c | |
| parent | 428ad1bc6dd766bb44171bba43a8a3219be77d2e (diff) | |
| download | lwn-805c4bc05705fb2b71ec970960b456eee9900953.tar.gz lwn-805c4bc05705fb2b71ec970960b456eee9900953.zip | |
tcp: fix req->saved_syn race
For the reasons explained in commit ce1050089c96 ("tcp/dccp: fix
ireq->pktopts race"), we need to make sure we do not access
req->saved_syn unless we own the request sock.
This fixes races for listeners using TCP_SAVE_SYN option.
Fixes: e994b2f0fb92 ("tcp: do not lock listener to process SYN packets")
Fixes: 079096f103fa ("tcp/dccp: install syn_recv requests into ehash table")
Signed-off-by: Eric Dumazet <edumazet@google.com>
Reported-by: Ying Cai <ycai@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Diffstat (limited to 'net/ipv6/tcp_ipv6.c')
| -rw-r--r-- | net/ipv6/tcp_ipv6.c | 20 |
1 files changed, 12 insertions, 8 deletions
diff --git a/net/ipv6/tcp_ipv6.c b/net/ipv6/tcp_ipv6.c index ea2f4d5440b5..c509e5562429 100644 --- a/net/ipv6/tcp_ipv6.c +++ b/net/ipv6/tcp_ipv6.c @@ -1140,14 +1140,18 @@ static struct sock *tcp_v6_syn_recv_sock(const struct sock *sk, struct sk_buff * goto out; } *own_req = inet_ehash_nolisten(newsk, req_to_sk(req_unhash)); - /* Clone pktoptions received with SYN, if we own the req */ - if (*own_req && ireq->pktopts) { - newnp->pktoptions = skb_clone(ireq->pktopts, - sk_gfp_atomic(sk, GFP_ATOMIC)); - consume_skb(ireq->pktopts); - ireq->pktopts = NULL; - if (newnp->pktoptions) - skb_set_owner_r(newnp->pktoptions, newsk); + if (*own_req) { + tcp_move_syn(newtp, req_unhash); + + /* Clone pktoptions received with SYN, if we own the req */ + if (ireq->pktopts) { + newnp->pktoptions = skb_clone(ireq->pktopts, + sk_gfp_atomic(sk, GFP_ATOMIC)); + consume_skb(ireq->pktopts); + ireq->pktopts = NULL; + if (newnp->pktoptions) + skb_set_owner_r(newnp->pktoptions, newsk); + } } return newsk; |