diff options
| author | Eric Dumazet <edumazet@google.com> | 2014-12-09 09:56:08 -0800 |
|---|---|---|
| committer | David S. Miller <davem@davemloft.net> | 2014-12-09 21:38:44 -0500 |
| commit | 0f85feae6b710ced3abad5b2b47d31dfcb956b62 (patch) | |
| tree | 17d1fadb2483724a83a814c33270cc94389890dc /net/ipv4/tcp_ipv4.c | |
| parent | f15650b7f94879667f253bc32de7431c1baf2d6e (diff) | |
tcp: fix more NULL deref after prequeue changes
When I cooked commit c3658e8d0f1 ("tcp: fix possible NULL dereference in
tcp_vX_send_reset()") I missed other spots we could deref a NULL
skb_dst(skb)
Again, if a socket is provided, we do not need skb_dst() to get a
pointer to network namespace : sock_net(sk) is good enough.
Reported-by: Dann Frazier <dann.frazier@canonical.com>
Bisected-by: Dann Frazier <dann.frazier@canonical.com>
Tested-by: Dann Frazier <dann.frazier@canonical.com>
Signed-off-by: Eric Dumazet <edumazet@google.com>
Fixes: ca777eff51f7 ("tcp: remove dst refcount false sharing for prequeue mode")
Signed-off-by: David S. Miller <davem@davemloft.net>
Diffstat (limited to 'net/ipv4/tcp_ipv4.c')
| -rw-r--r-- | net/ipv4/tcp_ipv4.c | 4 |
1 files changed, 2 insertions, 2 deletions
diff --git a/net/ipv4/tcp_ipv4.c b/net/ipv4/tcp_ipv4.c index 147be2024290..ef7089ca86e2 100644 --- a/net/ipv4/tcp_ipv4.c +++ b/net/ipv4/tcp_ipv4.c @@ -623,6 +623,7 @@ static void tcp_v4_send_reset(struct sock *sk, struct sk_buff *skb) arg.iov[0].iov_base = (unsigned char *)&rep; arg.iov[0].iov_len = sizeof(rep.th); + net = sk ? sock_net(sk) : dev_net(skb_dst(skb)->dev); #ifdef CONFIG_TCP_MD5SIG hash_location = tcp_parse_md5sig_option(th); if (!sk && hash_location) { @@ -633,7 +634,7 @@ static void tcp_v4_send_reset(struct sock *sk, struct sk_buff *skb) * Incoming packet is checked with md5 hash with finding key, * no RST generated if md5 hash doesn't match. */ - sk1 = __inet_lookup_listener(dev_net(skb_dst(skb)->dev), + sk1 = __inet_lookup_listener(net, &tcp_hashinfo, ip_hdr(skb)->saddr, th->source, ip_hdr(skb)->daddr, ntohs(th->source), inet_iif(skb)); @@ -681,7 +682,6 @@ static void tcp_v4_send_reset(struct sock *sk, struct sk_buff *skb) if (sk) arg.bound_dev_if = sk->sk_bound_dev_if; - net = dev_net(skb_dst(skb)->dev); arg.tos = ip_hdr(skb)->tos; ip_send_unicast_reply(net, skb, &TCP_SKB_CB(skb)->header.h4.opt, ip_hdr(skb)->saddr, ip_hdr(skb)->daddr, |