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=-8.4 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,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 30B67C55179 for ; Wed, 21 Oct 2020 16:39:52 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id CBB932177B for ; Wed, 21 Oct 2020 16:39:51 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=redhat.com header.i=@redhat.com header.b="A6bmnaZK" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2503109AbgJUQjs (ORCPT ); Wed, 21 Oct 2020 12:39:48 -0400 Received: from us-smtp-delivery-124.mimecast.com ([216.205.24.124]:24129 "EHLO us-smtp-delivery-124.mimecast.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S2503099AbgJUQjs (ORCPT ); Wed, 21 Oct 2020 12:39:48 -0400 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1603298385; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: in-reply-to:in-reply-to:references:references; bh=YklPv8/0OmCyptwlWRuggJNTmVWGoVbcydh3UqMAmHw=; b=A6bmnaZK0jLqAmalqOE8iGn7M+mlstCSubuc65Q3GfctfTaPiYk5V3+GKDlR7v6A54Vovm JmiBSKcofi4Irmdiu14IgB3TLH8q+ymn1mvatexWKGHjXVdZ90QE1X5zwKA14ePFKk68HY O2WRMxn9/a2M8wiz8o5+k6tOVZhxWt8= Received: from mimecast-mx01.redhat.com (mimecast-mx01.redhat.com [209.132.183.4]) (Using TLS) by relay.mimecast.com with ESMTP id us-mta-359-jJiRbKeWMNqcOmXwf7GJ-g-1; Wed, 21 Oct 2020 12:39:43 -0400 X-MC-Unique: jJiRbKeWMNqcOmXwf7GJ-g-1 Received: from smtp.corp.redhat.com (int-mx08.intmail.prod.int.phx2.redhat.com [10.5.11.23]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx01.redhat.com (Postfix) with ESMTPS id 969AB5F9C1; Wed, 21 Oct 2020 16:39:41 +0000 (UTC) Received: from madcap2.tricolour.ca (unknown [10.10.110.2]) by smtp.corp.redhat.com (Postfix) with ESMTPS id 2BC5E27CC1; Wed, 21 Oct 2020 16:39:28 +0000 (UTC) Date: Wed, 21 Oct 2020 12:39:26 -0400 From: Richard Guy Briggs To: Paul Moore Cc: nhorman@tuxdriver.com, linux-api@vger.kernel.org, containers@lists.linux-foundation.org, LKML , dhowells@redhat.com, Linux-Audit Mailing List , netfilter-devel@vger.kernel.org, ebiederm@xmission.com, simo@redhat.com, netdev@vger.kernel.org, linux-fsdevel@vger.kernel.org, Eric Paris , mpatel@redhat.com, Serge Hallyn Subject: Re: [PATCH ghak90 V9 05/13] audit: log container info of syscalls Message-ID: <20201021163926.GA3929765@madcap2.tricolour.ca> References: <6e2e10432e1400f747918eeb93bf45029de2aa6c.1593198710.git.rgb@redhat.com> <20200729194058.kcbsqjhzunjpipgm@madcap2.tricolour.ca> <20201002195231.GH2882171@madcap2.tricolour.ca> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20201002195231.GH2882171@madcap2.tricolour.ca> User-Agent: Mutt/1.10.1 (2018-07-13) X-Scanned-By: MIMEDefang 2.84 on 10.5.11.23 Precedence: bulk List-ID: X-Mailing-List: netfilter-devel@vger.kernel.org On 2020-10-02 15:52, Richard Guy Briggs wrote: > On 2020-08-21 15:15, Paul Moore wrote: > > On Wed, Jul 29, 2020 at 3:41 PM Richard Guy Briggs wrote: > > > On 2020-07-05 11:10, Paul Moore wrote: > > > > On Sat, Jun 27, 2020 at 9:22 AM Richard Guy Briggs wrote: > > > > ... > > > > > > > diff --git a/kernel/auditsc.c b/kernel/auditsc.c > > > > > index f03d3eb0752c..9e79645e5c0e 100644 > > > > > --- a/kernel/auditsc.c > > > > > +++ b/kernel/auditsc.c > > > > > @@ -1458,6 +1466,7 @@ static void audit_log_exit(void) > > > > > struct audit_buffer *ab; > > > > > struct audit_aux_data *aux; > > > > > struct audit_names *n; > > > > > + struct audit_contobj *cont; > > > > > > > > > > context->personality = current->personality; > > > > > > > > > > @@ -1541,7 +1550,7 @@ static void audit_log_exit(void) > > > > > for (aux = context->aux_pids; aux; aux = aux->next) { > > > > > struct audit_aux_data_pids *axs = (void *)aux; > > > > > > > > > > - for (i = 0; i < axs->pid_count; i++) > > > > > + for (i = 0; i < axs->pid_count; i++) { > > > > > if (audit_log_pid_context(context, axs->target_pid[i], > > > > > axs->target_auid[i], > > > > > axs->target_uid[i], > > > > > @@ -1549,14 +1558,20 @@ static void audit_log_exit(void) > > > > > axs->target_sid[i], > > > > > axs->target_comm[i])) > > > > > call_panic = 1; > > > > > + audit_log_container_id(context, axs->target_cid[i]); > > > > > + } > > > > > > > > It might be nice to see an audit event example including the > > > > ptrace/signal information. I'm concerned there may be some confusion > > > > about associating the different audit container IDs with the correct > > > > information in the event. > > > > > > This is the subject of ghat81, which is a test for ptrace and signal > > > records. > > > > > > This was the reason I had advocated for an op= field since there is a > > > possibility of multiple contid records per event. > > > > I think an "op=" field is the wrong way to link audit container ID to > > a particular record. It may be convenient, but I fear that it would > > be overloading the field too much. > > Ok, after looking at the field dictionary how about item, rel, ref or rec? > Item perhaps could be added to the OBJ_PID records, but that might be > overloading a field that is already used in PATH records. "rel" for > relates-to, "ref" for reference to, "rec" for record... Perhaps pid= > would be enough to tie this record to the OBJ_PID record or the SYSCALL > record, but in the case of network events, the pid may refer to a kernel > thread. > > > Like I said above, I think it would be good to see an audit event > > example including the ptrace/signal information. This way we can talk > > about it on-list and hash out the various solutions if it proves to be > > a problem. > > See the list posting from 2020-09-29 "auditing signals" pointing to > ghat81 test case about testing ptrace and signals from 18 months ago. > > I think I have a way to generate a signal to multiple targets in one > syscall... The added challenge is to also give those targets different > audit container identifiers. Here is an exmple I was able to generate after updating the testsuite script to include a signalling example of a nested audit container identifier: ---- type=PROCTITLE msg=audit(2020-10-21 10:31:16.655:6731) : proctitle=/usr/bin/perl -w containerid/test type=CONTAINER_ID msg=audit(2020-10-21 10:31:16.655:6731) : contid=7129731255799087104^3333941723245477888 type=OBJ_PID msg=audit(2020-10-21 10:31:16.655:6731) : opid=115583 oauid=root ouid=root oses=1 obj=unconfined_u:unconfined_r:unconfined_t:s0-s0:c0.c1023 ocomm=perl type=CONTAINER_ID msg=audit(2020-10-21 10:31:16.655:6731) : contid=3333941723245477888 type=OBJ_PID msg=audit(2020-10-21 10:31:16.655:6731) : opid=115580 oauid=root ouid=root oses=1 obj=unconfined_u:unconfined_r:unconfined_t:s0-s0:c0.c1023 ocomm=perl type=CONTAINER_ID msg=audit(2020-10-21 10:31:16.655:6731) : contid=8098399240850112512^3333941723245477888 type=OBJ_PID msg=audit(2020-10-21 10:31:16.655:6731) : opid=115582 oauid=root ouid=root oses=1 obj=unconfined_u:unconfined_r:unconfined_t:s0-s0:c0.c1023 ocomm=perl type=SYSCALL msg=audit(2020-10-21 10:31:16.655:6731) : arch=x86_64 syscall=kill success=yes exit=0 a0=0xfffe3c84 a1=SIGTERM a2=0x4d524554 a3=0x0 items=0 ppid=115564 pid=115567 auid=root uid=root gid=root euid=root suid=root fsuid=root egid=root sgid=root fsgid=root tty=ttyS0 ses=1 comm=perl exe=/usr/bin/perl subj=unconfined_u:unconfined_r:unconfined_t:s0-s0:c0.c1023 key=testsuite-1603290671-AcLtUulY ---- There are three CONTAINER_ID records which need some way of associating with OBJ_PID records. An additional CONTAINER_ID record would be present if the killing process itself had an audit container identifier. I think the most obvious way to connect them is with a pid= field in the CONTAINER_ID record. > > > > > @@ -1575,6 +1590,14 @@ static void audit_log_exit(void) > > > > > > > > > > audit_log_proctitle(); > > > > > > > > > > + rcu_read_lock(); > > > > > + cont = _audit_contobj_get(current); > > > > > + rcu_read_unlock(); > > > > > + audit_log_container_id(context, cont); > > > > > + rcu_read_lock(); > > > > > + _audit_contobj_put(cont); > > > > > + rcu_read_unlock(); > > > > > > > > Do we need to grab an additional reference for the audit container > > > > object here? We don't create any additional references here that > > > > persist beyond the lifetime of this function, right? > > > > > > Why do we need another reference? There's one for each pointer pointing > > > to it and so far we have just one from this task. Or are you thinking > > > of the contid hash list, which is only added to when a task points to it > > > and gets removed from that list when the last task stops pointing to it. > > > Later that gets more complicated with network namespaces and nested > > > container objects. For now we just needed it while generating the > > > record, then it gets freed. > > > > I don't think we need to grab an additional reference here, that is > > why I asked the question. The code above grabs a reference for the > > audit container ID object associated with the current task and then > > drops it before returning; if the current task, and it's associated > > audit container ID object, disappears in the middle of the function > > we've got much bigger worries :) > > I misunderstood your question previously thinking you wanted yet another > reference taken in this case, when in fact it was the opposite and you > thought the one taken here was superfluous. > > I don't *need* to grab the additional references here, but those are the > accessor functions that exist, so I either create sub-accessor functions > without the refcount manipulations that called from the primary accessor > functions or open code a reduncancy... The locking has been updated to > protect the _put by a spin-lock. Now that I look at it, the 4th to 7th > lines could be bypassed by a cont == NULL check. > > It is somewhat hidden now since this sequence of 7 commands has been > abstracted into another function that is called from a second location. > > > paul moore > > - RGB - RGB -- Richard Guy Briggs Sr. S/W Engineer, Kernel Security, Base Operating Systems Remote, Ottawa, Red Hat Canada IRC: rgb, SunRaycer Voice: +1.647.777.2635, Internal: (81) 32635