From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail.linuxfoundation.org ([140.211.169.12]:58398 "EHLO mail.linuxfoundation.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751685AbdBXIi4 (ORCPT ); Fri, 24 Feb 2017 03:38:56 -0500 From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Andrey Konovalov , Eric Dumazet , "David S. Miller" Subject: [PATCH 4.9 09/32] dccp: fix freeing skb too early for IPV6_RECVPKTINFO Date: Fri, 24 Feb 2017 09:37:53 +0100 Message-Id: <20170224083747.717994427@linuxfoundation.org> In-Reply-To: <20170224083746.364657938@linuxfoundation.org> References: <20170224083746.364657938@linuxfoundation.org> MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Sender: stable-owner@vger.kernel.org List-ID: 4.9-stable review patch. If anyone has any objections, please let me know. ------------------ From: Andrey Konovalov [ Upstream commit 5edabca9d4cff7f1f2b68f0bac55ef99d9798ba4 ] In the current DCCP implementation an skb for a DCCP_PKT_REQUEST packet is forcibly freed via __kfree_skb in dccp_rcv_state_process if dccp_v6_conn_request successfully returns. However, if IPV6_RECVPKTINFO is set on a socket, the address of the skb is saved to ireq->pktopts and the ref count for skb is incremented in dccp_v6_conn_request, so skb is still in use. Nevertheless, it gets freed in dccp_rcv_state_process. Fix by calling consume_skb instead of doing goto discard and therefore calling __kfree_skb. Similar fixes for TCP: fb7e2399ec17f1004c0e0ccfd17439f8759ede01 [TCP]: skb is unexpectedly freed. 0aea76d35c9651d55bbaf746e7914e5f9ae5a25d tcp: SYN packets are now simply consumed Signed-off-by: Andrey Konovalov Acked-by: Eric Dumazet Signed-off-by: David S. Miller Signed-off-by: Greg Kroah-Hartman --- net/dccp/input.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) --- a/net/dccp/input.c +++ b/net/dccp/input.c @@ -606,7 +606,8 @@ int dccp_rcv_state_process(struct sock * if (inet_csk(sk)->icsk_af_ops->conn_request(sk, skb) < 0) return 1; - goto discard; + consume_skb(skb); + return 0; } if (dh->dccph_type == DCCP_PKT_RESET) goto discard;