Re: [RFC PATCH ghak59 V1 1/6] audit: give a clue what CONFIG_CHANGE op was involved

On Thu, Jul 19, 2018 at 12:10 PM Richard Guy Briggs <rgb(a)redhat.com&gt; wrote: > On 2018-07-18 17:45, Paul Moore wrote: > > On Thu, Jul 12, 2018 at 8:43 PM Richard Guy Briggs <rgb(a)redhat.com&gt; 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&gt; 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. > > I don't see any CONFIG_CHANGE records generated in audit_receive_msg() > that are missing op= field. Can you narrow it down? Well, just grep'ing my way through audit_receive_msg() I see that AUDIT_ADD/DEL_RULE generates a CONFIG_CHANGE record.

> > > > > 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&gt; > > > > > --- > > > > > 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&gt; > > > 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 > > - RGB > > -- > Richard Guy Briggs <rgb(a)redhat.com&gt; > 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