From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mx1.redhat.com ([209.132.183.28]:34090 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727073AbeJYOiG (ORCPT ); Thu, 25 Oct 2018 10:38:06 -0400 Date: Thu, 25 Oct 2018 08:06:38 +0200 From: Steve Grubb To: Richard Guy Briggs Cc: Paul Moore , simo@redhat.com, carlos@redhat.com, linux-api@vger.kernel.org, containers@lists.linux-foundation.org, linux-kernel@vger.kernel.org, dhowells@redhat.com, linux-audit@redhat.com, netfilter-devel@vger.kernel.org, ebiederm@xmission.com, luto@kernel.org, netdev@vger.kernel.org, linux-fsdevel@vger.kernel.org, Eric Paris , Serge Hallyn , viro@zeniv.linux.org.uk Subject: Re: [PATCH ghak90 (was ghak32) V4 03/10] audit: log container info of syscalls Message-ID: <20181025080638.771621a3@ivy-bridge> In-Reply-To: <20181025004255.zl7p7j6gztouh2hh@madcap2.tricolour.ca> References: <34017c395d03a213d6b0d49b9964429bd32b283d.1533065887.git.rgb@redhat.com> <20181024151439.lavhanabsyxdrdvo@madcap2.tricolour.ca> <20181025004255.zl7p7j6gztouh2hh@madcap2.tricolour.ca> MIME-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Sender: linux-fsdevel-owner@vger.kernel.org List-ID: On Wed, 24 Oct 2018 20:42:55 -0400 Richard Guy Briggs wrote: > On 2018-10-24 16:55, Paul Moore wrote: > > On Wed, Oct 24, 2018 at 11:15 AM Richard Guy Briggs > > wrote: > > > On 2018-10-19 19:16, Paul Moore wrote: > > > > On Sun, Aug 5, 2018 at 4:32 AM Richard Guy Briggs > > > > wrote: > > > > > Create a new audit record AUDIT_CONTAINER to document the > > > > > audit container identifier of a process if it is present. > > > > > > > > > > Called from audit_log_exit(), syscalls are covered. > > > > > > > > > > A sample raw event: > > > > > type=SYSCALL msg=audit(1519924845.499:257): arch=c000003e > > > > > syscall=257 success=yes exit=3 a0=ffffff9c a1=56374e1cef30 > > > > > a2=241 a3=1b6 items=2 ppid=606 pid=635 auid=0 uid=0 gid=0 > > > > > euid=0 suid=0 fsuid=0 egid=0 sgid=0 fsgid=0 tty=pts0 ses=3 > > > > > comm="bash" exe="/usr/bin/bash" > > > > > subj=unconfined_u:unconfined_r:unconfined_t:s0-s0:c0.c1023 > > > > > key="tmpcontainerid" type=CWD msg=audit(1519924845.499:257): > > > > > cwd="/root" type=PATH msg=audit(1519924845.499:257): item=0 > > > > > name="/tmp/" inode=13863 dev=00:27 mode=041777 ouid=0 ogid=0 > > > > > rdev=00:00 obj=system_u:object_r:tmp_t:s0 nametype= PARENT > > > > > cap_fp=0000000000000000 cap_fi=0000000000000000 cap_fe=0 > > > > > cap_fver=0 type=PATH msg=audit(1519924845.499:257): item=1 > > > > > name="/tmp/tmpcontainerid" inode=17729 dev=00:27 mode=0100644 > > > > > ouid=0 ogid=0 rdev=00:00 > > > > > obj=unconfined_u:object_r:user_tmp_t:s0 nametype=CREATE > > > > > cap_fp=0000000000000000 cap_fi=0000000000000000 cap_fe=0 > > > > > cap_fver=0 type=PROCTITLE msg=audit(1519924845.499:257): > > > > > proctitle=62617368002D6300736C65657020313B206563686F2074657374203E202F746D702F746D70636F6E7461696E65726964 > > > > > type=CONTAINER msg=audit(1519924845.499:257): op=task > > > > > contid=123458 > > > > > > > > > > See: https://github.com/linux-audit/audit-kernel/issues/90 > > > > > See: https://github.com/linux-audit/audit-userspace/issues/51 > > > > > See: https://github.com/linux-audit/audit-testsuite/issues/64 > > > > > See: > > > > > https://github.com/linux-audit/audit-kernel/wiki/RFE-Audit-Container-ID > > > > > Signed-off-by: Richard Guy Briggs Acked-by: > > > > > Serge Hallyn Acked-by: Steve Grubb > > > > > --- > > > > > include/linux/audit.h | 7 +++++++ > > > > > include/uapi/linux/audit.h | 1 + > > > > > kernel/audit.c | 24 ++++++++++++++++++++++++ > > > > > kernel/auditsc.c | 3 +++ > > > > > 4 files changed, 35 insertions(+) > > > > > > > > ... > > > > > > > > > @@ -2045,6 +2045,30 @@ void audit_log_session_info(struct > > > > > audit_buffer *ab) audit_log_format(ab, " auid=%u ses=%u", > > > > > auid, sessionid); } > > > > > > > > > > +/* > > > > > + * audit_log_contid - report container info > > > > > + * @tsk: task to be recorded > > > > > + * @context: task or local context for record > > > > > + * @op: contid string description > > > > > + */ > > > > > +int audit_log_contid(struct task_struct *tsk, > > > > > + struct audit_context *context, > > > > > char *op) +{ > > > > > + struct audit_buffer *ab; > > > > > + > > > > > + if (!audit_contid_set(tsk)) > > > > > + return 0; > > > > > + /* Generate AUDIT_CONTAINER record with container ID > > > > > */ > > > > > + ab = audit_log_start(context, GFP_KERNEL, > > > > > AUDIT_CONTAINER); > > > > > + if (!ab) > > > > > + return -ENOMEM; > > > > > + audit_log_format(ab, "op=%s contid=%llu", > > > > > + op, audit_get_contid(tsk)); > > > > > + audit_log_end(ab); > > > > > + return 0; > > > > > +} > > > > > +EXPORT_SYMBOL(audit_log_contid); > > > > > > > > As discussed in the previous iteration of the patch, I prefer > > > > AUDIT_CONTAINER_ID here over AUDIT_CONTAINER. If you feel > > > > strongly about keeping it as-is with AUDIT_CONTAINER I suppose > > > > I could live with that, but it is isn't my first choice. > > > > > > I don't have a strong opinion on this one, mildly preferring the > > > shorter one only because it is shorter. > > > > We already have multiple AUDIT_CONTAINER* record types, so it seems > > as though we should use "AUDIT_CONTAINER" as a prefix of sorts, > > rather than a type itself. > > I'm fine with that. I'd still like to hear Steve's input. He had > stronger opinions than me. The creation event should be separate and distinct from the continuing use when its used as a supplemental record. IOW, binding the ID to a container is part of the lifecycle and needs to be kept distinct. -Steve > > > > However, I do care about the "op" field in this record. It just > > > > doesn't make any sense; the way you are using it it is more of a > > > > context field than an operations field, and even then why is the > > > > context important from a logging and/or security perspective? > > > > Drop it please. > > > > > > I'll rename it to whatever you like. I'd suggest "ref=". The > > > reason I think it is important is there are multiple sources that > > > aren't always obvious from the other records to which it is > > > associated. In the case of ptrace and signals, there can be many > > > target tasks listed (OBJ_PID) with no other way to distinguish > > > the matching audit container identifier records all for one > > > event. This is in addition to the default syscall container > > > identifier record. I'm not currently happy with the text content > > > to link the two, but that should be solvable (most obvious is > > > taret PID). Throwing away this information seems shortsighted. > > > > It would be helpful if you could generate real audit events > > demonstrating the problems you are describing, as well as a more > > standard syscall event, so we can discuss some possible solutions. > > If the auditted process is in a container and it ptraces or signals > another process in a container, there will be two AUDIT_CONTAINER > records for the same event that won't be identified as to which record > belongs to which process or other record (SYSCALL vs 1+ OBJ_PID > records). There could be many signals recorded, each with their own > OBJ_PID record. The first is stored in the audit context and > additional ones are stored in a chained struct that can accommodate > 16 entries each. > > (See audit_signal_info(), __audit_ptrace().) > > (As a side note, on code inspection it appears that a signal target > would get overwritten by a ptrace action if they were to happen in > that order.) > > > paul moore > > - 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 > > -- > Linux-audit mailing list > Linux-audit@redhat.com > https://www.redhat.com/mailman/listinfo/linux-audit