Re: [PATCH] bpf: emit audit messages upon successful prog load and unload

On 11/22/19 12:41 AM, Paul Moore wrote: > On Wed, Nov 20, 2019 at 4:49 PM Alexei Starovoitov > <alexei.starovoitov(a)gmail.com&gt; wrote: >> On Wed, Nov 20, 2019 at 1:46 PM Daniel Borkmann <daniel(a)iogearbox.net&gt; wrote: >>> On 11/20/19 10:38 PM, Jiri Olsa wrote: >>>> From: Daniel Borkmann <daniel(a)iogearbox.net&gt; >>>> >>>> Allow for audit messages to be emitted upon BPF program load and >>>> unload for having a timeline of events. The load itself is in >>>> syscall context, so additional info about the process initiating >>>> the BPF prog creation can be logged and later directly correlated >>>> to the unload event. >>>> >>>> The only info really needed from BPF side is the globally unique >>>> prog ID where then audit user space tooling can query / dump all >>>> info needed about the specific BPF program right upon load event >>>> and enrich the record, thus these changes needed here can be kept >>>> small and non-intrusive to the core. >>>> >>>> Raw example output: >>>> >>>> # auditctl -D >>>> # auditctl -a always,exit -F arch=x86_64 -S bpf >>>> # ausearch --start recent -m 1334 >>>> [...] >>>> ---- >>>> time->Wed Nov 20 12:45:51 2019 >>>> type=PROCTITLE msg=audit(1574271951.590:8974): proctitle="./test_verifier" >>>> type=SYSCALL msg=audit(1574271951.590:8974): arch=c000003e syscall=321 success=yes exit=14 a0=5 a1=7ffe2d923e80 a2=78 a3=0 items=0 ppid=742 pid=949 auid=0 uid=0 gid=0 euid=0 suid=0 fsuid=0 egid=0 sgid=0 fsgid=0 tty=pts0 ses=2 comm="test_verifier" exe="/root/bpf-next/tools/testing/selftests/bpf/test_verifier" subj=unconfined_u:unconfined_r:unconfined_t:s0-s0:c0.c1023 key=(null) >>>> type=UNKNOWN[1334] msg=audit(1574271951.590:8974): auid=0 uid=0 gid=0 ses=2 subj=unconfined_u:unconfined_r:unconfined_t:s0-s0:c0.c1023 pid=949 comm="test_verifier" exe="/root/bpf-next/tools/testing/selftests/bpf/test_verifier" prog-id=3260 event=LOAD >>>> ---- >>>> time->Wed Nov 20 12:45:51 2019 >>>> type=UNKNOWN[1334] msg=audit(1574271951.590:8975): prog-id=3260 event=UNLOAD >>>> ---- >>>> [...] >>>> >>>> Signed-off-by: Daniel Borkmann <daniel(a)iogearbox.net&gt; >>>> Signed-off-by: Jiri Olsa <jolsa(a)kernel.org&gt; >>> >>> LGTM, thanks for the rebase! >> >> Applied to bpf-next. Thanks! > > [NOTE: added linux-audit to the To/CC line] > > Wait a minute, why was the linux-audit list not CC'd on this? Why are > you merging a patch into -next that adds to the uapi definition *and* > creates a new audit record while we are at -rc8? > > Aside from that I'm concerned that you are relying on audit userspace > changes that might not be okay; I see the PR below, but I don't see > any comment on it from Steve (it is his audit userspace). I also > don't see a corresponding test added to the audit-testsuite, which is > a common requirement for new audit functionality (link below). I'm > also fairly certain we don't want this new BPF record to look like how > you've coded it up in bpf_audit_prog(); duplicating the fields with > audit_log_task() is wrong, you've either already got them via an > associated record (which you get from passing non-NULL as the first > parameter to audit_log_start()), or you don't because there is no > associated syscall/task (which you get from passing NULL as the first > parameter). Please revert, un-merge, etc. this patch from bpf-next; > it should not go into Linus' tree as written. Fair enough, up to you guys. My impression was that this is mainly coming from RHEL use case [0] and given that the original patch was back in Oct 2018 [1] that you've sorted it out by now RH internally and agreed to proceed with this patch for BPF given the rebase + resend ... seems not then. :(

Given the change is mostly trivial, are there any major objections for Jiri to follow-up? Otherwise worst case probably easier to revert in net-next.

[0] slide 11, https://linuxplumbersconf.org/event/4/contributions/460/attachments/244/4... [1] https://lore.kernel.org/netdev/20181004135038.2876-1-daniel@iogearbox.net/