Re: [PATCH v2] lag_conf: Added pointer check and continue

From: Simon Horman
Date: Wed Nov 16 2022 - 05:48:54 EST


On Wed, Nov 16, 2022 at 10:40:00AM +0100, Simon Horman wrote:
> On Wed, Nov 16, 2022 at 11:13:36AM +0300, Denis Arefev wrote:
> > Return value of a function 'kmalloc_array' is dereferenced at
> > lag_conf.c:347 without checking for null,
> > but it is usually checked for this function.
> >
> > Found by Linux Verification Center (linuxtesting.org) with SVACE.
> >
> > Signed-off-by: Denis Arefev <arefev@xxxxxxxxx>
>
> Thanks Denis,
>
> I'll let me colleague Yinjun review the functional change,
> although, based on his earlier feedback, it does look good to me.

I confirmed with Yinjun that he is happy with the patch,
other than the comments that I made.

> From my side I have two nits:
>
> 1. I think the patch prefix should be 'nfp: flower:'
> i.e., the patch subject should be more like
> [PATCH v2] nfp: flower: handle allocation failure in LAG delayed work
>
> 2. Inline, below.
>
> Kind regards,
> Simon
>
> > diff --git a/drivers/net/ethernet/netronome/nfp/flower/lag_conf.c b/drivers/net/ethernet/netronome/nfp/flower/lag_conf.c
> > index 63907aeb3884..1aaec4cb9f55 100644
> > --- a/drivers/net/ethernet/netronome/nfp/flower/lag_conf.c
> > +++ b/drivers/net/ethernet/netronome/nfp/flower/lag_conf.c
> > @@ -276,7 +276,7 @@ static void nfp_fl_lag_do_work(struct work_struct *work)
> >
> > mutex_lock(&lag->lock);
> > list_for_each_entry_safe(entry, storage, &lag->group_list, list) {
> > - struct net_device *iter_netdev, **acti_netdevs;
> > + struct net_device *iter_netdev, **acti_netdevs = NULL;
>
> 2. I don't think it is necessary (or therefore desirable)
> to initialise acti_netdevs to NULL.
> As far as I can tell the variable is already always
> set before being used.
>
> ...