From mboxrd@z Thu Jan 1 00:00:00 1970 From: Patrick McHardy Subject: [PATCH 2/3] netfilter: nf_tables: check for overflow of rule dlen field Date: Tue, 3 Mar 2015 20:04:19 +0000 Message-ID: <1425413060-6187-3-git-send-email-kaber@trash.net> References: <1425413060-6187-1-git-send-email-kaber@trash.net> Cc: netfilter-devel@vger.kernel.org To: pablo@netfilter.org Return-path: Received: from stinky.trash.net ([213.144.137.162]:44928 "EHLO stinky.trash.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1756476AbbCCUE0 (ORCPT ); Tue, 3 Mar 2015 15:04:26 -0500 In-Reply-To: <1425413060-6187-1-git-send-email-kaber@trash.net> Sender: netfilter-devel-owner@vger.kernel.org List-ID: Check that the space required for the expressions doesn't exceed the size of the dlen field, which would lead to the iterators crashing. Signed-off-by: Patrick McHardy --- net/netfilter/nf_tables_api.c | 4 ++++ 1 file changed, 4 insertions(+) diff --git a/net/netfilter/nf_tables_api.c b/net/netfilter/nf_tables_api.c index 6fb532b..7baafd5 100644 --- a/net/netfilter/nf_tables_api.c +++ b/net/netfilter/nf_tables_api.c @@ -1968,6 +1968,10 @@ static int nf_tables_newrule(struct sock *nlsk, struct sk_buff *skb, n++; } } + /* Check for overflow of dlen field */ + err = -EFBIG; + if (size >= 1 << 12) + goto err1; if (nla[NFTA_RULE_USERDATA]) ulen = nla_len(nla[NFTA_RULE_USERDATA]); -- 2.1.0