From 3257d8b12f954c462d29de6201664a846328a522 Mon Sep 17 00:00:00 2001 From: Eric Dumazet Date: Mon, 10 Aug 2015 15:07:34 -0700 Subject: inet: fix possible request socket leak In commit b357a364c57c9 ("inet: fix possible panic in reqsk_queue_unlink()"), I missed fact that tcp_check_req() can return the listener socket in one case, and that we must release the request socket refcount or we leak it. Tested: Following packetdrill test template shows the issue 0 socket(..., SOCK_STREAM, IPPROTO_TCP) = 3 +0 setsockopt(3, SOL_SOCKET, SO_REUSEADDR, [1], 4) = 0 +0 bind(3, ..., ...) = 0 +0 listen(3, 1) = 0 +0 < S 0:0(0) win 2920 +0 > S. 0:0(0) ack 1 +.002 < . 1:1(0) ack 21 win 2920 +0 > R 21:21(0) Fixes: b357a364c57c9 ("inet: fix possible panic in reqsk_queue_unlink()") Signed-off-by: Eric Dumazet Signed-off-by: David S. Miller --- net/ipv4/tcp_ipv4.c | 2 +- net/ipv6/tcp_ipv6.c | 2 +- 2 files changed, 2 insertions(+), 2 deletions(-) (limited to 'net') diff --git a/net/ipv4/tcp_ipv4.c b/net/ipv4/tcp_ipv4.c index d7d4c2b79cf2..0ea2e1c5d395 100644 --- a/net/ipv4/tcp_ipv4.c +++ b/net/ipv4/tcp_ipv4.c @@ -1348,7 +1348,7 @@ static struct sock *tcp_v4_hnd_req(struct sock *sk, struct sk_buff *skb) req = inet_csk_search_req(sk, th->source, iph->saddr, iph->daddr); if (req) { nsk = tcp_check_req(sk, skb, req, false); - if (!nsk) + if (!nsk || nsk == sk) reqsk_put(req); return nsk; } diff --git a/net/ipv6/tcp_ipv6.c b/net/ipv6/tcp_ipv6.c index 6748c4277aff..7a6cea5e4274 100644 --- a/net/ipv6/tcp_ipv6.c +++ b/net/ipv6/tcp_ipv6.c @@ -943,7 +943,7 @@ static struct sock *tcp_v6_hnd_req(struct sock *sk, struct sk_buff *skb) &ipv6_hdr(skb)->daddr, tcp_v6_iif(skb)); if (req) { nsk = tcp_check_req(sk, skb, req, false); - if (!nsk) + if (!nsk || nsk == sk) reqsk_put(req); return nsk; } -- cgit v1.2.3