[PATCH v3 3/4] selinux: remove some useless BUG_ONs

[Ondrej Mosnacek]

On Fri, Jan 25, 2019 at 2:49 PM Stephen Smalley <sds at tycho.nsa.gov> wrote:
> On 1/25/19 5:06 AM, Ondrej Mosnacek wrote:
> > These BUG_ONs do not really protect from any catastrophic situation so
> > there is no need to have them there.
>
> They are to catch bugs in callers that pass requested==0.  That is
> always indicative of a bug in the caller (e.g. failed to correctly
> compute the permissions).  Otherwise, we will silently allow such calls
> and not notice them.
>
> At the least, they should be WARN_ONs.

OK, seems that switching to WARN_ON() will be a better choice.

Paul, you can apply the series without this patch and I will post a
corrected patch separately (if that's OK with you).

>
> >
> > Signed-off-by: Ondrej Mosnacek <omosnace at redhat.com>
> > ---
> >   security/selinux/avc.c | 3 ---
> >   1 file changed, 3 deletions(-)
> >
> > diff --git a/security/selinux/avc.c b/security/selinux/avc.c
> > index 5ebad47391c9..478fa4213c25 100644
> > --- a/security/selinux/avc.c
> > +++ b/security/selinux/avc.c
> > @@ -1044,7 +1044,6 @@ int avc_has_extended_perms(struct selinux_state *state,
> >       int rc = 0, rc2;
> >
> >       xp_node = &local_xp_node;
> > -     BUG_ON(!requested);
> >
> >       rcu_read_lock();
> >
> > @@ -1134,8 +1133,6 @@ inline int avc_has_perm_noaudit(struct selinux_state *state,
> >       int rc = 0;
> >       u32 denied;
> >
> > -     BUG_ON(!requested);
> > -
> >       rcu_read_lock();
> >
> >       node = avc_lookup(state->avc, ssid, tsid, tclass);
> >
>

-- 
Ondrej Mosnacek <omosnace at redhat dot com>
Associate Software Engineer, Security Technologies
Red Hat, Inc.