Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S966442AbbFJQCu (ORCPT ); Wed, 10 Jun 2015 12:02:50 -0400 Received: from ip4-83-240-67-251.cust.nbox.cz ([83.240.67.251]:36041 "EHLO ip4-83-240-18-248.cust.nbox.cz" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S933810AbbFJP1m (ORCPT ); Wed, 10 Jun 2015 11:27:42 -0400 From: Jiri Slaby To: stable@vger.kernel.org Cc: linux-kernel@vger.kernel.org, Ian Wilson , Pablo Neira Ayuso , Jiri Slaby Subject: [PATCH 3.12 001/111] netfilter: Zero the tuple in nfnl_cthelper_parse_tuple() Date: Wed, 10 Jun 2015 17:25:50 +0200 Message-Id: <93091169a673f49c2574cddf1ef858cf0704f646.1433943052.git.jslaby@suse.cz> X-Mailer: git-send-email 2.4.2 In-Reply-To: References: Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 2120 Lines: 56 From: Ian Wilson 3.12-stable review patch. If anyone has any objections, please let me know. =============== [ upstream commit 78146572b9cd20452da47951812f35b1ad4906be ] nfnl_cthelper_parse_tuple() is called from nfnl_cthelper_new(), nfnl_cthelper_get() and nfnl_cthelper_del(). In each case they pass a pointer to an nf_conntrack_tuple data structure local variable: struct nf_conntrack_tuple tuple; ... ret = nfnl_cthelper_parse_tuple(&tuple, tb[NFCTH_TUPLE]); The problem is that this local variable is not initialized, and nfnl_cthelper_parse_tuple() only initializes two fields: src.l3num and dst.protonum. This leaves all other fields with undefined values based on whatever is on the stack: tuple->src.l3num = ntohs(nla_get_be16(tb[NFCTH_TUPLE_L3PROTONUM])); tuple->dst.protonum = nla_get_u8(tb[NFCTH_TUPLE_L4PROTONUM]); The symptom observed was that when the rpc and tns helpers were added then traffic to port 1536 was being sent to user-space. Signed-off-by: Ian Wilson Signed-off-by: Pablo Neira Ayuso Signed-off-by: Jiri Slaby --- net/netfilter/nfnetlink_cthelper.c | 3 +++ 1 file changed, 3 insertions(+) diff --git a/net/netfilter/nfnetlink_cthelper.c b/net/netfilter/nfnetlink_cthelper.c index 9e287cb56a04..7f035f0772ee 100644 --- a/net/netfilter/nfnetlink_cthelper.c +++ b/net/netfilter/nfnetlink_cthelper.c @@ -77,6 +77,9 @@ nfnl_cthelper_parse_tuple(struct nf_conntrack_tuple *tuple, if (!tb[NFCTH_TUPLE_L3PROTONUM] || !tb[NFCTH_TUPLE_L4PROTONUM]) return -EINVAL; + /* Not all fields are initialized so first zero the tuple */ + memset(tuple, 0, sizeof(struct nf_conntrack_tuple)); + tuple->src.l3num = ntohs(nla_get_be16(tb[NFCTH_TUPLE_L3PROTONUM])); tuple->dst.protonum = nla_get_u8(tb[NFCTH_TUPLE_L4PROTONUM]); -- 2.4.2 -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/