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 3FE51C4332F for ; Wed, 2 Nov 2022 18:17:14 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S230208AbiKBSRN (ORCPT ); Wed, 2 Nov 2022 14:17:13 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:43634 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229598AbiKBSRM (ORCPT ); Wed, 2 Nov 2022 14:17:12 -0400 Received: from mail.netfilter.org (mail.netfilter.org [217.70.188.207]) by lindbergh.monkeyblade.net (Postfix) with ESMTP id 3A0D31DF08 for ; Wed, 2 Nov 2022 11:17:12 -0700 (PDT) Date: Wed, 2 Nov 2022 19:17:07 +0100 From: Pablo Neira Ayuso To: Jozsef Kadlecsik Cc: netfilter-devel@vger.kernel.org, Daniel Xu Subject: Re: [PATCH v2] netfilter: ipset: enforce documented limit to prevent allocating huge memory Message-ID: References: <20221102094047.460574-1-kadlec@netfilter.org> MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline In-Reply-To: <20221102094047.460574-1-kadlec@netfilter.org> Precedence: bulk List-ID: X-Mailing-List: netfilter-devel@vger.kernel.org On Wed, Nov 02, 2022 at 10:40:47AM +0100, Jozsef Kadlecsik wrote: > Daniel Xu reported that the hash:net,iface type of the ipset subsystem does > not limit adding the same network with different interfaces to a set, which > can lead to huge memory usage or allocation failure. > > The quick reproducer is > > $ ipset create ACL.IN.ALL_PERMIT hash:net,iface hashsize 1048576 timeout 0 > $ for i in $(seq 0 100); do /sbin/ipset add ACL.IN.ALL_PERMIT 0.0.0.0/0,kaf_$i timeout 0 -exist; done > > The backtrace when vmalloc fails: > > [Tue Oct 25 00:13:08 2022] ipset: vmalloc error: size 1073741848, exceeds total pages > <...> > [Tue Oct 25 00:13:08 2022] Call Trace: > [Tue Oct 25 00:13:08 2022] > [Tue Oct 25 00:13:08 2022] dump_stack_lvl+0x48/0x60 > [Tue Oct 25 00:13:08 2022] warn_alloc+0x155/0x180 > [Tue Oct 25 00:13:08 2022] __vmalloc_node_range+0x72a/0x760 > [Tue Oct 25 00:13:08 2022] ? hash_netiface4_add+0x7c0/0xb20 > [Tue Oct 25 00:13:08 2022] ? __kmalloc_large_node+0x4a/0x90 > [Tue Oct 25 00:13:08 2022] kvmalloc_node+0xa6/0xd0 > [Tue Oct 25 00:13:08 2022] ? hash_netiface4_resize+0x99/0x710 > <...> > > The fix is to enforce the limit documented in the ipset(8) manpage: > > > The internal restriction of the hash:net,iface set type is that the same > > network prefix cannot be stored with more than 64 different interfaces > > in a single set. Applied, thanks