From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 9F6C1ECAAD3 for ; Wed, 7 Sep 2022 08:26:27 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S229621AbiIGI00 (ORCPT ); Wed, 7 Sep 2022 04:26:26 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:39912 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229464AbiIGI00 (ORCPT ); Wed, 7 Sep 2022 04:26:26 -0400 Received: from mail.netfilter.org (mail.netfilter.org [217.70.188.207]) by lindbergh.monkeyblade.net (Postfix) with ESMTP id 07D7495AEF for ; Wed, 7 Sep 2022 01:26:23 -0700 (PDT) From: Pablo Neira Ayuso To: netfilter-devel@vger.kernel.org Subject: [PATCH nf] netfilter: nfnetlink_osf: fix possible bogus match in nf_osf_find() Date: Wed, 7 Sep 2022 10:26:18 +0200 Message-Id: <20220907082618.1193201-1-pablo@netfilter.org> X-Mailer: git-send-email 2.30.2 MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: netfilter-devel@vger.kernel.org nf_osf_find() incorrectly returns true on mismatch, this leads to copying uninitialized memory area in nft_osf which can be used to leak stale kernel stack data to userspace. Fixes: 22c7652cdaa8 ("netfilter: nft_osf: Add version option support") Signed-off-by: Pablo Neira Ayuso --- net/netfilter/nfnetlink_osf.c | 4 +++- 1 file changed, 3 insertions(+), 1 deletion(-) diff --git a/net/netfilter/nfnetlink_osf.c b/net/netfilter/nfnetlink_osf.c index 0fa2e2030427..ee6840bd5933 100644 --- a/net/netfilter/nfnetlink_osf.c +++ b/net/netfilter/nfnetlink_osf.c @@ -269,6 +269,7 @@ bool nf_osf_find(const struct sk_buff *skb, struct nf_osf_hdr_ctx ctx; const struct tcphdr *tcp; struct tcphdr _tcph; + bool found = false; memset(&ctx, 0, sizeof(ctx)); @@ -283,10 +284,11 @@ bool nf_osf_find(const struct sk_buff *skb, data->genre = f->genre; data->version = f->version; + found = true; break; } - return true; + return found; } EXPORT_SYMBOL_GPL(nf_osf_find); -- 2.30.2