Re: [PATCH] flow_offload: action should not be NULL when it is referenced

From: Ido Schimmel
Date: Wed Aug 18 2021 - 09:40:57 EST


On Wed, Aug 18, 2021 at 08:36:55AM -0400, Jamal Hadi Salim wrote:
> On 2021-08-18 7:58 a.m., Ido Schimmel wrote:
> > On Sat, Jun 26, 2021 at 04:56:06AM -0700, 13145886936@xxxxxxx wrote:
> > > From: gushengxian <gushengxian@xxxxxxxxxx>
> > >
> > > "action" should not be NULL when it is referenced.
> > >
> > > Signed-off-by: gushengxian <13145886936@xxxxxxx>
> > > Signed-off-by: gushengxian <gushengxian@xxxxxxxxxx>
> > > ---
> > > include/net/flow_offload.h | 12 +++++++-----
> > > 1 file changed, 7 insertions(+), 5 deletions(-)
> > >
> > > diff --git a/include/net/flow_offload.h b/include/net/flow_offload.h
> > > index dc5c1e69cd9f..69c9eabf8325 100644
> > > --- a/include/net/flow_offload.h
> > > +++ b/include/net/flow_offload.h
> > > @@ -319,12 +319,14 @@ flow_action_mixed_hw_stats_check(const struct flow_action *action,
> > > if (flow_offload_has_one_action(action))
> > > return true;
> > > - flow_action_for_each(i, action_entry, action) {
> > > - if (i && action_entry->hw_stats != last_hw_stats) {
> > > - NL_SET_ERR_MSG_MOD(extack, "Mixing HW stats types for actions is not supported");
> > > - return false;
> > > + if (action) {
> >
> > This patch generates a smatch warning:
> >
> > include/net/flow_offload.h:322 flow_action_mixed_hw_stats_check() warn: variable dereferenced before check 'action' (see line 319)
> >
> > Why the patch is needed? 'action' is already dereferenced in
> > flow_offload_has_one_action()
> >
>
> Yep, doesnt make sense at all.

Will send a revert