Re: [PATCH 2/3] smack: call WARN_ONCE() instead of calling audit_log_start()

[Richard Guy Briggs <rgb@redhat.com>]

On Fri, Dec 06, 2013 at 10:40:56AM -0800, Casey Schaufler wrote:
> On 12/4/2013 6:45 PM, Richard Guy Briggs wrote:
> > Remove the call to audit_log() (which call audit_log_start()) and deal with
> > the errors in the caller, logging only once if the condition is met.  Calling
> > audit_log_start() in this location makes buffer allocation and locking more
> > complicated in the calling tree (audit_filter_user()).
> >
> > Signed-off-by: Richard Guy Briggs <rgb@redhat.com>
> 
> I'm not opposed to this change, but have you actually tried it?

No, do you have concerns?

It is a projection based on the selinux_audit_match_rule() patch in the
same set.

> > ---
> >  security/smack/smack_lsm.c |    5 ++---
> >  1 files changed, 2 insertions(+), 3 deletions(-)
> >
> > diff --git a/security/smack/smack_lsm.c b/security/smack/smack_lsm.c
> > index 8825375..185e2e7 100644
> > --- a/security/smack/smack_lsm.c
> > +++ b/security/smack/smack_lsm.c
> > @@ -3615,9 +3615,8 @@ static int smack_audit_rule_match(u32 secid, u32 field, u32 op, void *vrule,
> >  	struct smack_known *skp;
> >  	char *rule = vrule;
> >  
> > -	if (!rule) {
> > -		audit_log(actx, GFP_ATOMIC, AUDIT_SELINUX_ERR,
> > -			  "Smack: missing rule\n");
> > +	if (unlikely(!rule)) {
> > +		WARN_ONCE(1, "Smack: missing rule\n");
> >  		return -ENOENT;
> >  	}
> >  
> 

- RGB

--
Richard Guy Briggs <rbriggs@redhat.com>
Senior Software Engineer, Kernel Security, AMER ENG Base Operating Systems, Red Hat
Remote, Ottawa, Canada
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