On Thu, Jul 12, 2018 at 8:43 PM Richard Guy Briggs <rgb(a)redhat.com> wrote:
On 2018-06-28 15:41, Paul Moore wrote:
> On Thu, Jun 14, 2018 at 4:23 PM Richard Guy Briggs <rgb(a)redhat.com> wrote:
> > The failure to add an audit rule due to audit locked gives no clue
> > what CONFIG_CHANGE operation failed.
> > Similarly the set operation is the only other operation that doesn't
> > give the "op=" field to indicate the action.
> > All other CONFIG_CHANGE records include an op= field to give a clue as
> > to what sort of configuration change is being executed.
> >
> > Since these are the only CONFIG_CHANGE records that that do not have an
> > op= field, add them to bring them in line with the rest.
>
> Normally this would be an immediate reject because this patch inserts
> a field into an existing record, but the CONFIG_CHANGE record is so
> variable (supposedly bad in its own right) that I don't this really
> matters.
>
> With that out of the way, I think this patch is fine, but I don't
> think it is complete. At the very least there is another
> CONFIG_CHANGE record in audit_watch_log_rule_change() that doesn't
> appear to include an "op" field. If we want to make sure we have an
> "op" field in every CONFIG_CHANGE record, let's actually add them all
> :)
The version I'm looking at already had it when it was added in 2009.
Yup, there it is ... now I'm wondering what tree I was looking at as a
reference while reviewing this?
/me scratches head
This one doesn't add the auid and ses fields because they will
be
covered by the linking of this record with the syscall record via the
audit_context() introduced in another patch.
Yeah, I'm not concerned about that for the reasons you state.
> and one more in audit_receive_msg(). There may be more.
I believe they're covered by other patches in the ghak59 set.
If they are in the later patches it might be good to move those "op="
additions into this patch.
> > Old records:
> > type=CONFIG_CHANGE msg=audit(1519812997.781:374): pid=610 uid=0 auid=0 ses=1
subj=... audit_enabled=2 res=0
> > type=CONFIG_CHANGE msg=audit(2018-06-14 14:55:04.507:47) : audit_enabled=1
old=1 auid=unset ses=unset subj=... res=yes
> >
> > New records:
> > type=CONFIG_CHANGE msg=audit(1520958477.855:100): pid=610 uid=0 auid=0 ses=1
subj=... op=add_rule audit_enabled=2 res=0
> >
> > type=CONFIG_CHANGE msg=audit(2018-06-14 14:55:04.507:47) : op=set
audit_enabled=1 old=1 auid=unset ses=unset subj=... res=yes
> >
> > See:
https://github.com/linux-audit/audit-kernel/issues/59
> > Signed-off-by: Richard Guy Briggs <rgb(a)redhat.com>
> > ---
> > kernel/audit.c | 6 ++++--
> > 1 file changed, 4 insertions(+), 2 deletions(-)
> >
> > diff --git a/kernel/audit.c b/kernel/audit.c
> > index e7478cb..ad54339 100644
> > --- a/kernel/audit.c
> > +++ b/kernel/audit.c
> > @@ -403,7 +403,7 @@ static int audit_log_config_change(char *function_name, u32
new, u32 old,
> > ab = audit_log_start(NULL, GFP_KERNEL, AUDIT_CONFIG_CHANGE);
> > if (unlikely(!ab))
> > return rc;
> > - audit_log_format(ab, "%s=%u old=%u", function_name, new,
old);
> > + audit_log_format(ab, "op=set %s=%u old=%u", function_name,
new, old);
> > audit_log_session_info(ab);
> > rc = audit_log_task_context(ab);
> > if (rc)
> > @@ -1365,7 +1365,9 @@ static int audit_receive_msg(struct sk_buff *skb, struct
nlmsghdr *nlh)
> > return -EINVAL;
> > if (audit_enabled == AUDIT_LOCKED) {
> > audit_log_common_recv_msg(&ab,
AUDIT_CONFIG_CHANGE);
> > - audit_log_format(ab, " audit_enabled=%d
res=0", audit_enabled);
> > + audit_log_format(ab, " op=%s_rule audit_enabled=%d
res=0",
> > + msg_type == AUDIT_ADD_RULE ?
"add" : "remove",
> > + audit_enabled);
> > audit_log_end(ab);
> > return -EPERM;
> > }
> > --
> > 1.8.3.1
>
> --
> paul moore
>
www.paul-moore.com
- RGB
--
Richard Guy Briggs <rgb(a)redhat.com>
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
--
paul moore
www.paul-moore.com