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

From: Simon Horman
Date: Wed Nov 16 2022 - 04:40:20 EST


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.

>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.

...