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 X-Spam-Level: X-Spam-Status: No, score=-8.5 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI,SPF_HELO_NONE, SPF_PASS,USER_AGENT_SANE_1 autolearn=unavailable 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 2F496C433EB for ; Mon, 27 Jul 2020 15:06:16 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 120DE2064B for ; Mon, 27 Jul 2020 15:06:16 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1730683AbgG0PGK (ORCPT ); Mon, 27 Jul 2020 11:06:10 -0400 Received: from verein.lst.de ([213.95.11.211]:44011 "EHLO verein.lst.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1729630AbgG0PGJ (ORCPT ); Mon, 27 Jul 2020 11:06:09 -0400 Received: by verein.lst.de (Postfix, from userid 2407) id 8445868B05; Mon, 27 Jul 2020 17:06:01 +0200 (CEST) Date: Mon, 27 Jul 2020 17:06:01 +0200 From: Christoph Hellwig To: "Jason A. Donenfeld" Cc: Christoph Hellwig , "David S. Miller" , Jakub Kicinski , Alexei Starovoitov , Daniel Borkmann , Alexey Kuznetsov , Hideaki YOSHIFUJI , Eric Dumazet , linux-crypto@vger.kernel.org, linux-kernel@vger.kernel.org, netdev@vger.kernel.org, bpf@vger.kernel.org, netfilter-devel@vger.kernel.org, coreteam@netfilter.org, linux-sctp@vger.kernel.org, linux-hams@vger.kernel.org, linux-bluetooth@vger.kernel.org, bridge@lists.linux-foundation.org, linux-can@vger.kernel.org, dccp@vger.kernel.org, linux-decnet-user@lists.sourceforge.net, linux-wpan@vger.kernel.org, linux-s390@vger.kernel.org, mptcp@lists.01.org, lvs-devel@vger.kernel.org, rds-devel@oss.oracle.com, linux-afs@lists.infradead.org, tipc-discussion@lists.sourceforge.net, linux-x25@vger.kernel.org Subject: Re: [PATCH 12/26] netfilter: switch nf_setsockopt to sockptr_t Message-ID: <20200727150601.GA3447@lst.de> References: <20200723060908.50081-1-hch@lst.de> <20200723060908.50081-13-hch@lst.de> <20200727150310.GA1632472@zx2c4.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20200727150310.GA1632472@zx2c4.com> User-Agent: Mutt/1.5.17 (2007-11-01) Sender: linux-bluetooth-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-bluetooth@vger.kernel.org On Mon, Jul 27, 2020 at 05:03:10PM +0200, Jason A. Donenfeld wrote: > Hi Christoph, > > On Thu, Jul 23, 2020 at 08:08:54AM +0200, Christoph Hellwig wrote: > > diff --git a/net/ipv4/ip_sockglue.c b/net/ipv4/ip_sockglue.c > > index da933f99b5d517..42befbf12846c0 100644 > > --- a/net/ipv4/ip_sockglue.c > > +++ b/net/ipv4/ip_sockglue.c > > @@ -1422,7 +1422,8 @@ int ip_setsockopt(struct sock *sk, int level, > > optname != IP_IPSEC_POLICY && > > optname != IP_XFRM_POLICY && > > !ip_mroute_opt(optname)) > > - err = nf_setsockopt(sk, PF_INET, optname, optval, optlen); > > + err = nf_setsockopt(sk, PF_INET, optname, USER_SOCKPTR(optval), > > + optlen); > > #endif > > return err; > > } > > diff --git a/net/ipv4/netfilter/ip_tables.c b/net/ipv4/netfilter/ip_tables.c > > index 4697d09c98dc3e..f2a9680303d8c0 100644 > > --- a/net/ipv4/netfilter/ip_tables.c > > +++ b/net/ipv4/netfilter/ip_tables.c > > @@ -1102,7 +1102,7 @@ __do_replace(struct net *net, const char *name, unsigned int valid_hooks, > > } > > > > static int > > -do_replace(struct net *net, const void __user *user, unsigned int len) > > +do_replace(struct net *net, sockptr_t arg, unsigned int len) > > { > > int ret; > > struct ipt_replace tmp; > > @@ -1110,7 +1110,7 @@ do_replace(struct net *net, const void __user *user, unsigned int len) > > void *loc_cpu_entry; > > struct ipt_entry *iter; > > > > - if (copy_from_user(&tmp, user, sizeof(tmp)) != 0) > > + if (copy_from_sockptr(&tmp, arg, sizeof(tmp)) != 0) > > return -EFAULT; > > > > /* overflow check */ > > @@ -1126,8 +1126,8 @@ do_replace(struct net *net, const void __user *user, unsigned int len) > > return -ENOMEM; > > > > loc_cpu_entry = newinfo->entries; > > - if (copy_from_user(loc_cpu_entry, user + sizeof(tmp), > > - tmp.size) != 0) { > > + sockptr_advance(arg, sizeof(tmp)); > > + if (copy_from_sockptr(loc_cpu_entry, arg, tmp.size) != 0) { > > ret = -EFAULT; > > goto free_newinfo; > > } > > Something along this path seems to have broken with this patch. An > invocation of `iptables -A INPUT -m length --length 1360 -j DROP` now > fails, with > > nf_setsockopt->do_replace->translate_table->check_entry_size_and_hooks: > (unsigned char *)e + e->next_offset > limit ==> TRUE > > resulting in the whole call chain returning -EINVAL. It bisects back to > this commit. This is on net-next. This is another use o sockptr_advance that Ido already found a problem in. I'm looking into this at the moment..