summaryrefslogtreecommitdiff
diff options
context:
space:
mode:
authorChristoph Paasch <cpaasch@apple.com>2017-12-11 00:05:46 -0800
committerGreg Kroah-Hartman <gregkh@linuxfoundation.org>2018-01-02 20:35:11 +0100
commit7887a700ce613bcf200edda53ca824d691c6ee8f (patch)
treee44eaa3f152d17dbd757be608e747a06d6f1197e
parenta4bf8efd2bcb233c422adc663552515dc4ee0da8 (diff)
tcp md5sig: Use skb's saddr when replying to an incoming segment
[ Upstream commit 30791ac41927ebd3e75486f9504b6d2280463bf0 ] The MD5-key that belongs to a connection is identified by the peer's IP-address. When we are in tcp_v4(6)_reqsk_send_ack(), we are replying to an incoming segment from tcp_check_req() that failed the seq-number checks. Thus, to find the correct key, we need to use the skb's saddr and not the daddr. This bug seems to have been there since quite a while, but probably got unnoticed because the consequences are not catastrophic. We will call tcp_v4_reqsk_send_ack only to send a challenge-ACK back to the peer, thus the connection doesn't really fail. Fixes: 9501f9722922 ("tcp md5sig: Let the caller pass appropriate key for tcp_v{4,6}_do_calc_md5_hash().") Signed-off-by: Christoph Paasch <cpaasch@apple.com> Reviewed-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
-rw-r--r--net/ipv4/tcp_ipv4.c2
-rw-r--r--net/ipv6/tcp_ipv6.c2
2 files changed, 2 insertions, 2 deletions
diff --git a/net/ipv4/tcp_ipv4.c b/net/ipv4/tcp_ipv4.c
index d577ec07a0d8..b3960738464e 100644
--- a/net/ipv4/tcp_ipv4.c
+++ b/net/ipv4/tcp_ipv4.c
@@ -828,7 +828,7 @@ static void tcp_v4_reqsk_send_ack(const struct sock *sk, struct sk_buff *skb,
tcp_time_stamp,
req->ts_recent,
0,
- tcp_md5_do_lookup(sk, (union tcp_md5_addr *)&ip_hdr(skb)->daddr,
+ tcp_md5_do_lookup(sk, (union tcp_md5_addr *)&ip_hdr(skb)->saddr,
AF_INET),
inet_rsk(req)->no_srccheck ? IP_REPLY_ARG_NOSRCCHECK : 0,
ip_hdr(skb)->tos);
diff --git a/net/ipv6/tcp_ipv6.c b/net/ipv6/tcp_ipv6.c
index 7ac2365aa6fb..eb624547382f 100644
--- a/net/ipv6/tcp_ipv6.c
+++ b/net/ipv6/tcp_ipv6.c
@@ -962,7 +962,7 @@ static void tcp_v6_reqsk_send_ack(const struct sock *sk, struct sk_buff *skb,
tcp_rsk(req)->rcv_nxt,
req->rsk_rcv_wnd >> inet_rsk(req)->rcv_wscale,
tcp_time_stamp, req->ts_recent, sk->sk_bound_dev_if,
- tcp_v6_md5_do_lookup(sk, &ipv6_hdr(skb)->daddr),
+ tcp_v6_md5_do_lookup(sk, &ipv6_hdr(skb)->saddr),
0, 0);
}