From patchwork Mon Mar 12 17:59:02 2018 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Pablo Neira Ayuso X-Patchwork-Id: 884663 X-Patchwork-Delegate: pablo@netfilter.org Return-Path: X-Original-To: incoming@patchwork.ozlabs.org Delivered-To: patchwork-incoming@bilbo.ozlabs.org Authentication-Results: ozlabs.org; spf=none (mailfrom) smtp.mailfrom=vger.kernel.org (client-ip=209.132.180.67; helo=vger.kernel.org; envelope-from=netfilter-devel-owner@vger.kernel.org; receiver=) Authentication-Results: ozlabs.org; dmarc=none (p=none dis=none) header.from=netfilter.org Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by ozlabs.org (Postfix) with ESMTP id 400Qjm0Bg6z9sMM for ; Tue, 13 Mar 2018 04:59:39 +1100 (AEDT) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S932804AbeCLR7i (ORCPT ); Mon, 12 Mar 2018 13:59:38 -0400 Received: from mail.us.es ([193.147.175.20]:56262 "EHLO mail.us.es" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S932617AbeCLR7g (ORCPT ); Mon, 12 Mar 2018 13:59:36 -0400 Received: from antivirus1-rhel7.int (unknown [192.168.2.11]) by mail.us.es (Postfix) with ESMTP id 9B0E45B7FC for ; Mon, 12 Mar 2018 18:59:32 +0100 (CET) Received: from antivirus1-rhel7.int (localhost [127.0.0.1]) by antivirus1-rhel7.int (Postfix) with ESMTP id 874D0DA552 for ; Mon, 12 Mar 2018 18:59:32 +0100 (CET) Received: by antivirus1-rhel7.int (Postfix, from userid 99) id 7CA6FDA808; Mon, 12 Mar 2018 18:59:32 +0100 (CET) X-Spam-Checker-Version: SpamAssassin 3.4.1 (2015-04-28) on antivirus1-rhel7.int X-Spam-Level: X-Spam-Status: No, score=-108.2 required=7.5 tests=ALL_TRUSTED,BAYES_50, SMTPAUTH_US2,USER_IN_WHITELIST autolearn=disabled version=3.4.1 Received: from antivirus1-rhel7.int (localhost [127.0.0.1]) by antivirus1-rhel7.int (Postfix) with ESMTP id 9D9E3DA727; Mon, 12 Mar 2018 18:59:30 +0100 (CET) Received: from 192.168.1.97 (192.168.1.97) by antivirus1-rhel7.int (F-Secure/fsigk_smtp/550/antivirus1-rhel7.int); Mon, 12 Mar 2018 18:59:30 +0100 (CET) X-Virus-Status: clean(F-Secure/fsigk_smtp/550/antivirus1-rhel7.int) Received: from salvia.here (129.166.216.87.static.jazztel.es [87.216.166.129]) (Authenticated sender: pneira@us.es) by entrada.int (Postfix) with ESMTPA id 3EFEA4265A2F; Mon, 12 Mar 2018 18:59:30 +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 Subject: [PATCH 12/30] netfilter: x_tables: limit allocation requests for blob rule heads Date: Mon, 12 Mar 2018 18:59:02 +0100 Message-Id: <20180312175920.9022-13-pablo@netfilter.org> X-Mailer: git-send-email 2.11.0 In-Reply-To: <20180312175920.9022-1-pablo@netfilter.org> References: <20180312175920.9022-1-pablo@netfilter.org> X-Virus-Scanned: ClamAV using ClamSMTP Sender: netfilter-devel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: netfilter-devel@vger.kernel.org From: Florian Westphal This is a very conservative limit (134217728 rules), but good enough to not trigger frequent oom from syzkaller. Signed-off-by: Florian Westphal Signed-off-by: Pablo Neira Ayuso --- net/netfilter/x_tables.c | 3 +++ 1 file changed, 3 insertions(+) diff --git a/net/netfilter/x_tables.c b/net/netfilter/x_tables.c index dc68ac49614a..01f8e122e74e 100644 --- a/net/netfilter/x_tables.c +++ b/net/netfilter/x_tables.c @@ -894,6 +894,9 @@ EXPORT_SYMBOL(xt_check_entry_offsets); */ unsigned int *xt_alloc_entry_offsets(unsigned int size) { + if (size > XT_MAX_TABLE_SIZE / sizeof(unsigned int)) + return NULL; + return kvmalloc_array(size, sizeof(unsigned int), GFP_KERNEL | __GFP_ZERO); }