From patchwork Sun Jan 3 19:29:18 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Pablo Neira Ayuso X-Patchwork-Id: 11995877 X-Patchwork-Delegate: kuba@kernel.org Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-16.8 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER,INCLUDES_PATCH, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,USER_AGENT_GIT autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 83F7DC433DB for ; Sun, 3 Jan 2021 19:30:30 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 4B1372078D for ; Sun, 3 Jan 2021 19:30:30 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727633AbhACTaK (ORCPT ); Sun, 3 Jan 2021 14:30:10 -0500 Received: from correo.us.es ([193.147.175.20]:40762 "EHLO mail.us.es" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727294AbhACTaJ (ORCPT ); Sun, 3 Jan 2021 14:30:09 -0500 Received: from antivirus1-rhel7.int (unknown [192.168.2.11]) by mail.us.es (Postfix) with ESMTP id 7A42CDA709 for ; Sun, 3 Jan 2021 20:28:52 +0100 (CET) Received: from antivirus1-rhel7.int (localhost [127.0.0.1]) by antivirus1-rhel7.int (Postfix) with ESMTP id 6AF43DA722 for ; Sun, 3 Jan 2021 20:28:52 +0100 (CET) Received: by antivirus1-rhel7.int (Postfix, from userid 99) id 60733DA704; Sun, 3 Jan 2021 20:28:52 +0100 (CET) Received: from antivirus1-rhel7.int (localhost [127.0.0.1]) by antivirus1-rhel7.int (Postfix) with ESMTP id 41CE6DA72F; Sun, 3 Jan 2021 20:28:50 +0100 (CET) Received: from 192.168.1.97 (192.168.1.97) by antivirus1-rhel7.int (F-Secure/fsigk_smtp/550/antivirus1-rhel7.int); Sun, 03 Jan 2021 20:28:50 +0100 (CET) X-Virus-Status: clean(F-Secure/fsigk_smtp/550/antivirus1-rhel7.int) Received: from localhost.localdomain (unknown [90.77.255.23]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) (Authenticated sender: pneira@us.es) by entrada.int (Postfix) with ESMTPSA id 0EE56426CC85; Sun, 3 Jan 2021 20:28:50 +0100 (CET) X-SMTPAUTHUS: auth mail.us.es From: Pablo Neira Ayuso To: netfilter-devel@vger.kernel.org Cc: davem@davemloft.net, netdev@vger.kernel.org, kuba@kernel.org Subject: [PATCH net 1/3] netfilter: xt_RATEEST: reject non-null terminated string from userspace Date: Sun, 3 Jan 2021 20:29:18 +0100 Message-Id: <20210103192920.18639-2-pablo@netfilter.org> X-Mailer: git-send-email 2.20.1 In-Reply-To: <20210103192920.18639-1-pablo@netfilter.org> References: <20210103192920.18639-1-pablo@netfilter.org> MIME-Version: 1.0 X-Virus-Scanned: ClamAV using ClamSMTP Precedence: bulk List-ID: X-Mailing-List: netdev@vger.kernel.org X-Patchwork-Delegate: kuba@kernel.org From: Florian Westphal syzbot reports: detected buffer overflow in strlen [..] Call Trace: strlen include/linux/string.h:325 [inline] strlcpy include/linux/string.h:348 [inline] xt_rateest_tg_checkentry+0x2a5/0x6b0 net/netfilter/xt_RATEEST.c:143 strlcpy assumes src is a c-string. Check info->name before its used. Reported-by: syzbot+e86f7c428c8c50db65b4@syzkaller.appspotmail.com Fixes: 5859034d7eb8793 ("[NETFILTER]: x_tables: add RATEEST target") Signed-off-by: Florian Westphal Signed-off-by: Pablo Neira Ayuso --- net/netfilter/xt_RATEEST.c | 3 +++ 1 file changed, 3 insertions(+) diff --git a/net/netfilter/xt_RATEEST.c b/net/netfilter/xt_RATEEST.c index 37253d399c6b..0d5c422f8745 100644 --- a/net/netfilter/xt_RATEEST.c +++ b/net/netfilter/xt_RATEEST.c @@ -115,6 +115,9 @@ static int xt_rateest_tg_checkentry(const struct xt_tgchk_param *par) } cfg; int ret; + if (strnlen(info->name, sizeof(est->name)) >= sizeof(est->name)) + return -ENAMETOOLONG; + net_get_random_once(&jhash_rnd, sizeof(jhash_rnd)); mutex_lock(&xn->hash_lock);