lists.openwall.net | lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening PHC | |
Open Source and information security mailing list archives
| ||
|
Date: Mon, 1 Aug 2022 11:19:35 -0400 From: Paul Moore <paul@...l-moore.com> To: Frederick Lawler <fred@...udflare.com>, kpsingh@...nel.org Cc: Martin KaFai Lau <kafai@...com>, revest@...omium.org, jackmanb@...omium.org, ast@...nel.org, daniel@...earbox.net, andrii@...nel.org, songliubraving@...com, yhs@...com, john.fastabend@...il.com, jmorris@...ei.org, serge@...lyn.com, stephen.smalley.work@...il.com, eparis@...isplace.org, shuah@...nel.org, brauner@...nel.org, casey@...aufler-ca.com, ebiederm@...ssion.com, bpf@...r.kernel.org, linux-security-module@...r.kernel.org, selinux@...r.kernel.org, linux-kselftest@...r.kernel.org, linux-kernel@...r.kernel.org, netdev@...r.kernel.org, kernel-team@...udflare.com, cgzones@...glemail.com, karl@...badwolfsecurity.com Subject: Re: [PATCH v3 0/4] Introduce security_create_user_ns() On Mon, Aug 1, 2022 at 9:13 AM Frederick Lawler <fred@...udflare.com> wrote: > On 7/22/22 7:20 AM, Paul Moore wrote: > > On July 22, 2022 2:12:03 AM Martin KaFai Lau <kafai@...com> wrote: > > > >> On Thu, Jul 21, 2022 at 12:28:04PM -0500, Frederick Lawler wrote: > >>> While creating a LSM BPF MAC policy to block user namespace creation, we > >>> used the LSM cred_prepare hook because that is the closest hook to prevent > >>> a call to create_user_ns(). > >>> > >>> The calls look something like this: > >>> > >>> cred = prepare_creds() > >>> security_prepare_creds() > >>> call_int_hook(cred_prepare, ... > >>> if (cred) > >>> create_user_ns(cred) > >>> > >>> We noticed that error codes were not propagated from this hook and > >>> introduced a patch [1] to propagate those errors. > >>> > >>> The discussion notes that security_prepare_creds() > >>> is not appropriate for MAC policies, and instead the hook is > >>> meant for LSM authors to prepare credentials for mutation. [2] > >>> > >>> Ultimately, we concluded that a better course of action is to introduce > >>> a new security hook for LSM authors. [3] > >>> > >>> This patch set first introduces a new security_create_user_ns() function > >>> and userns_create LSM hook, then marks the hook as sleepable in BPF. > >> Patch 1 and 4 still need review from the lsm/security side. > > > > This patchset is in my review queue and assuming everything checks out, I expect to merge it after the upcoming merge window closes. > > > > I would also need an ACK from the BPF LSM folks, but they're CC'd on this patchset. > > Based on last weeks comments, should I go ahead and put up v4 for > 5.20-rc1 when that drops, or do I need to wait for more feedback? In general it rarely hurts to make another revision, and I think you've gotten some decent feedback on this draft, especially around the BPF LSM tests; I think rebasing on Linus tree after the upcoming io_uring changes are merged would be a good idea. Although as a reminder to the BPF LSM folks - I'm looking at you KP Singh :) - I need an ACK from you guys before I merge the BPF related patches (patches {2,3}/4). For the record, I think the SELinux portion of this patchset (path 4/4) is fine. There is the issue of Eric's NACK, but I believe the responses that followed his comment sufficiently addressed those concerns and it has now been a week with no further comment from Eric; we should continue to move forward with this. -- paul-moore.com
Powered by blists - more mailing lists