4.1-stable review patch. If anyone has any objections, please let me know. ------------------ From: Eric Dumazet <edumazet@xxxxxxxxxx> [ Upstream commit 3257d8b12f954c462d29de6201664a846328a522 ] 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 <mss 1460,sackOK,nop,nop> +0 > S. 0:0(0) ack 1 <mss 1460,nop,nop,sackOK> +.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 <edumazet@xxxxxxxxxx> Signed-off-by: David S. Miller <davem@xxxxxxxxxxxxx> Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> --- net/ipv4/tcp_ipv4.c | 2 +- net/ipv6/tcp_ipv6.c | 2 +- 2 files changed, 2 insertions(+), 2 deletions(-) --- a/net/ipv4/tcp_ipv4.c +++ b/net/ipv4/tcp_ipv4.c @@ -1348,7 +1348,7 @@ static struct sock *tcp_v4_hnd_req(struc 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; } --- a/net/ipv6/tcp_ipv6.c +++ b/net/ipv6/tcp_ipv6.c @@ -946,7 +946,7 @@ static struct sock *tcp_v6_hnd_req(struc &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; } -- To unsubscribe from this list: send the line "unsubscribe stable" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html