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=-6.8 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH, MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED 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 51E42C48BE8 for ; Sat, 22 Jun 2019 22:57:13 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 28D302073F for ; Sat, 22 Jun 2019 22:57:13 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=chromium.org header.i=@chromium.org header.b="Jegslib+" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726296AbfFVW5M (ORCPT ); Sat, 22 Jun 2019 18:57:12 -0400 Received: from mail-pf1-f193.google.com ([209.85.210.193]:42532 "EHLO mail-pf1-f193.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726310AbfFVW5M (ORCPT ); Sat, 22 Jun 2019 18:57:12 -0400 Received: by mail-pf1-f193.google.com with SMTP id q10so5385520pff.9 for ; Sat, 22 Jun 2019 15:57:12 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=chromium.org; s=google; h=date:from:to:cc:subject:message-id:references:mime-version :content-disposition:in-reply-to; bh=sqha2utqvS7jEDuaSANIP+IQgbDijQvpcyiultNgG4c=; b=Jegslib++7gU5iwNNP993QtdTa1uzkEdA8m1R1sXVnvaNqaPDh/aws9sAP6TOpsCFW Uf5Ry8f9wgGpWsBWjpjlRGrJJ3iy4lPEl1d0EI3+HXX41s+N9jF2p+TX1hgsV0u8y9Z9 HttKqK/eK5N1IwZ21+5+UUXDVvBswQbiGFJLE= X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:date:from:to:cc:subject:message-id:references :mime-version:content-disposition:in-reply-to; bh=sqha2utqvS7jEDuaSANIP+IQgbDijQvpcyiultNgG4c=; b=gyyTdCu9E5xOkB6uouh+xYvgO07Xbneq8Av2/YSogr7sWRnkEm2HyxmddlOKqYfNml oF8AzN3/4bAx0cwFgRu+9T1V71TZHqlNW+A2drSEXm9OZnhH1nZkkjUbBcPwBw12nmh+ SNGEAjN1UBYdwQriPItV6vigGOKOQLPXkGOnlcYEdHycQRLx0/nagL+5apGvXY/XgQVF 8OMU2wdcSjRNJFfVG1nRiP3XMWcRtmnzb+1F2y6WxriAmIDVppI4XXPccaEc6Lj6fG9Z 6c2XX/k0236e2rVdA5+Sg2WpIeJdBu9VCBmeVB8cdqwJz1OdA3ZuGiKig4HezT3limes IGCw== X-Gm-Message-State: APjAAAWwqEHovXb95sw/C1PG7Ha02epZOWZirsAdXU+tnha/FQyq5Yot 6bkxZ0r4R9uF2DPcCnSx2kymmg== X-Google-Smtp-Source: APXvYqzqRu98gAacIS5qmRffSqqC6N4yBzw8By5aYqJxNHHiKkyKGJ/h2SuY3r/FjkGD9zJpsYTFag== X-Received: by 2002:a17:90a:3724:: with SMTP id u33mr15191894pjb.19.1561244231772; Sat, 22 Jun 2019 15:57:11 -0700 (PDT) Received: from www.outflux.net (smtp.outflux.net. [198.145.64.163]) by smtp.gmail.com with ESMTPSA id k8sm7143780pfk.177.2019.06.22.15.57.10 (version=TLS1_2 cipher=ECDHE-RSA-CHACHA20-POLY1305 bits=256/256); Sat, 22 Jun 2019 15:57:11 -0700 (PDT) Date: Sat, 22 Jun 2019 15:57:10 -0700 From: Kees Cook To: Casey Schaufler Cc: casey.schaufler@intel.com, jmorris@namei.org, linux-security-module@vger.kernel.org, selinux@vger.kernel.org, john.johansen@canonical.com, penguin-kernel@i-love.sakura.ne.jp, paul@paul-moore.com, sds@tycho.nsa.gov Subject: Re: [PATCH v3 20/24] LSM: security_secid_to_secctx in netlink netfilter Message-ID: <201906221557.C043141@keescook> References: <20190621185233.6766-1-casey@schaufler-ca.com> <20190621185233.6766-21-casey@schaufler-ca.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20190621185233.6766-21-casey@schaufler-ca.com> Sender: owner-linux-security-module@vger.kernel.org Precedence: bulk List-ID: On Fri, Jun 21, 2019 at 11:52:29AM -0700, Casey Schaufler wrote: > Change netlink netfilter interfaces to use lsmcontext > pointers, and remove scaffolding. > > Signed-off-by: Casey Schaufler Reviewed-by: Kees Cook -Kees > --- > net/netfilter/nfnetlink_queue.c | 32 +++++++++++++------------------- > 1 file changed, 13 insertions(+), 19 deletions(-) > > diff --git a/net/netfilter/nfnetlink_queue.c b/net/netfilter/nfnetlink_queue.c > index 6da00c7add5b..69efb688383f 100644 > --- a/net/netfilter/nfnetlink_queue.c > +++ b/net/netfilter/nfnetlink_queue.c > @@ -305,12 +305,10 @@ static int nfqnl_put_sk_uidgid(struct sk_buff *skb, struct sock *sk) > return -1; > } > > -static u32 nfqnl_get_sk_secctx(struct sk_buff *skb, char **secdata) > +static u32 nfqnl_get_sk_secctx(struct sk_buff *skb, struct lsmcontext *context) > { > - u32 seclen = 0; > #if IS_ENABLED(CONFIG_NETWORK_SECMARK) > struct lsmblob blob; > - struct lsmcontext context; > > if (!skb || !sk_fullsock(skb->sk)) > return 0; > @@ -318,15 +316,16 @@ static u32 nfqnl_get_sk_secctx(struct sk_buff *skb, char **secdata) > read_lock_bh(&skb->sk->sk_callback_lock); > > if (skb->secmark) { > + /* Any LSM might be looking for the secmark */ > lsmblob_init(&blob, skb->secmark); > - security_secid_to_secctx(&blob, &context); > - *secdata = context.context; > + security_secid_to_secctx(&blob, context); > } > > read_unlock_bh(&skb->sk->sk_callback_lock); > - seclen = context.len; > + return context->len; > +#else > + return 0; > #endif > - return seclen; > } > > static u32 nfqnl_get_bridge_size(struct nf_queue_entry *entry) > @@ -402,8 +401,7 @@ nfqnl_build_packet_message(struct net *net, struct nfqnl_instance *queue, > enum ip_conntrack_info uninitialized_var(ctinfo); > struct nfnl_ct_hook *nfnl_ct; > bool csum_verify; > - struct lsmcontext scaff; /* scaffolding */ > - char *secdata = NULL; > + struct lsmcontext context; > u32 seclen = 0; > > size = nlmsg_total_size(sizeof(struct nfgenmsg)) > @@ -470,7 +468,7 @@ nfqnl_build_packet_message(struct net *net, struct nfqnl_instance *queue, > } > > if ((queue->flags & NFQA_CFG_F_SECCTX) && entskb->sk) { > - seclen = nfqnl_get_sk_secctx(entskb, &secdata); > + seclen = nfqnl_get_sk_secctx(entskb, &context); > if (seclen) > size += nla_total_size(seclen); > } > @@ -605,7 +603,7 @@ nfqnl_build_packet_message(struct net *net, struct nfqnl_instance *queue, > nfqnl_put_sk_uidgid(skb, entskb->sk) < 0) > goto nla_put_failure; > > - if (seclen && nla_put(skb, NFQA_SECCTX, seclen, secdata)) > + if (seclen && nla_put(skb, NFQA_SECCTX, context.len, context.context)) > goto nla_put_failure; > > if (ct && nfnl_ct->build(skb, ct, ctinfo, NFQA_CT, NFQA_CT_INFO) < 0) > @@ -633,10 +631,8 @@ nfqnl_build_packet_message(struct net *net, struct nfqnl_instance *queue, > } > > nlh->nlmsg_len = skb->len; > - if (seclen) { > - lsmcontext_init(&scaff, secdata, seclen, 0); > - security_release_secctx(&scaff); > - } > + if (seclen) > + security_release_secctx(&context); > return skb; > > nla_put_failure: > @@ -644,10 +640,8 @@ nfqnl_build_packet_message(struct net *net, struct nfqnl_instance *queue, > kfree_skb(skb); > net_err_ratelimited("nf_queue: error creating packet message\n"); > nlmsg_failure: > - if (seclen) { > - lsmcontext_init(&scaff, secdata, seclen, 0); > - security_release_secctx(&scaff); > - } > + if (seclen) > + security_release_secctx(&context); > return NULL; > } > > -- > 2.20.1 > -- Kees Cook