From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Florian Westphal , Pablo Neira Ayuso , Sasha Levin Subject: [PATCH 4.9 128/138] netfilter: nf_tables: fix oob access Date: Tue, 28 Nov 2017 11:23:49 +0100 Message-Id: <20171128100554.874269434@linuxfoundation.org> In-Reply-To: <20171128100544.706504901@linuxfoundation.org> References: <20171128100544.706504901@linuxfoundation.org> MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Sender: linux-kernel-owner@vger.kernel.org List-ID: 4.9-stable review patch. If anyone has any objections, please let me know. ------------------ From: Florian Westphal [ Upstream commit 3e38df136e453aa69eb4472108ebce2fb00b1ba6 ] BUG: KASAN: slab-out-of-bounds in nf_tables_rule_destroy+0xf1/0x130 at addr ffff88006a4c35c8 Read of size 8 by task nft/1607 When we've destroyed last valid expr, nft_expr_next() returns an invalid expr. We must not dereference it unless it passes != nft_expr_last() check. Signed-off-by: Florian Westphal Signed-off-by: Pablo Neira Ayuso Signed-off-by: Sasha Levin Signed-off-by: Greg Kroah-Hartman --- net/netfilter/nf_tables_api.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) --- a/net/netfilter/nf_tables_api.c +++ b/net/netfilter/nf_tables_api.c @@ -2068,7 +2068,7 @@ static void nf_tables_rule_destroy(const * is called on error from nf_tables_newrule(). */ expr = nft_expr_first(rule); - while (expr->ops && expr != nft_expr_last(rule)) { + while (expr != nft_expr_last(rule) && expr->ops) { nf_tables_expr_destroy(ctx, expr); expr = nft_expr_next(expr); }