On 2021-05-10 18:48, Paul Moore wrote: > On Sun, May 9, 2021 at 2:33 PM Michael Weiß > <[email protected]> wrote: > > > > Audit subsystem was disabled in total for user namespaces other than > > the initial namespace. > > > > If audit is enabled by kernel command line or audtid in initial namespace, > > it is now possible to allow at least logging of userspace applications > > inside of non-initial namespaces if CAP_AUDIT_WRITE in the corresponding > > namespace is held. > > > > This allows logging of, e.g., PAM or opensshd inside user namespaced > > system containers. > > > > Signed-off-by: Michael Weiß <[email protected]> > > --- > > kernel/audit.c | 10 ++++++++-- > > 1 file changed, 8 insertions(+), 2 deletions(-) > > I think this needs to wait on the audit container ID patchset to land.
That will interact with this, for sure and others related. Given that there are non-init namespaces involved that may not be part of containers, I would prefer to wait until namespaces are also optionally documentable in audit events before permitting this change. A patchset exists, but it has been deferred until the audit container identifier patchset is settled. (See https://github.com/linux-audit/audit-kernel/issues/32 ) > > diff --git a/kernel/audit.c b/kernel/audit.c > > index 121d37e700a6..b5cc0669c3d7 100644 > > --- a/kernel/audit.c > > +++ b/kernel/audit.c > > @@ -1012,7 +1012,13 @@ static int audit_netlink_ok(struct sk_buff *skb, u16 > > msg_type) > > * userspace will reject all logins. This should be removed when we > > * support non init namespaces!! > > */ > > - if (current_user_ns() != &init_user_ns) > > + /* > > + * If audit is enabled by kernel command line or audtid in the > > initial > > + * namespace allow at least logging of userspace applications > > inside of > > + * non-initial namespaces according to CAP_AUDIT_WRITE is held in > > the > > + * corresponding namespace. > > + */ > > + if ((current_user_ns() != &init_user_ns) && !audit_enabled) > > return -ECONNREFUSED; > > > > switch (msg_type) { > > @@ -1043,7 +1049,7 @@ static int audit_netlink_ok(struct sk_buff *skb, u16 > > msg_type) > > case AUDIT_USER: > > case AUDIT_FIRST_USER_MSG ... AUDIT_LAST_USER_MSG: > > case AUDIT_FIRST_USER_MSG2 ... AUDIT_LAST_USER_MSG2: > > - if (!netlink_capable(skb, CAP_AUDIT_WRITE)) > > + if (!netlink_ns_capable(skb, current_user_ns(), > > CAP_AUDIT_WRITE)) > > err = -EPERM; > > break; > > default: /* bad msg */ > > -- > > 2.20.1 > > -- > paul moore > www.paul-moore.com > - RGB -- Richard Guy Briggs <[email protected]> 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 [email protected] https://listman.redhat.com/mailman/listinfo/linux-audit
