Re: [PATCH net-next] net: mana: hardening: Reject zero max_num_queues from MANA_QUERY_VPORT_CONFIG

[Erni Sri Satya Vennela]

On Thu, Mar 26, 2026 at 10:48:10AM -0700, Erni Sri Satya Vennela wrote:
> As a part of MANA hardening for CVM, validate that max_num_sq and
> max_num_rq returned by MANA_QUERY_VPORT_CONFIG are not zero. These
> values flow into apc->num_queues, which is used as an allocation count
> and loop bound. A zero value would result in zero-size allocations and
> incorrect driver behavior.
> 
> Return -EPROTO if either value is zero.
> 
> Signed-off-by: Erni Sri Satya Vennela <ernis@xxxxxxxxxxxxxxxxxxx>
> ---
>  drivers/net/ethernet/microsoft/mana/mana_en.c | 6 ++++++
>  1 file changed, 6 insertions(+)
> 
> diff --git a/drivers/net/ethernet/microsoft/mana/mana_en.c b/drivers/net/ethernet/microsoft/mana/mana_en.c
> index b39e8b920791..a4197b4b0597 100644
> --- a/drivers/net/ethernet/microsoft/mana/mana_en.c
> +++ b/drivers/net/ethernet/microsoft/mana/mana_en.c
> @@ -1249,6 +1249,12 @@ static int mana_query_vport_cfg(struct mana_port_context *apc, u32 vport_index,
>  
>  	*max_sq = resp.max_num_sq;
>  	*max_rq = resp.max_num_rq;
> +
> +	if (*max_sq == 0 || *max_rq == 0) {
> +		netdev_err(apc->ndev, "Invalid max queues from vPort config\n");
> +		return -EPROTO;
> +	}
> +
>  	if (resp.num_indirection_ent > 0 &&
>  	    resp.num_indirection_ent <= MANA_INDIRECT_TABLE_MAX_SIZE &&
>  	    is_power_of_2(resp.num_indirection_ent)) {
> -- 
> 2.34.1

Hi,

Gentle reminder regarding this patch.

I would really appreciate any feedback whenever you get a chance.
Please let me know if any changes are required from my side.

Thanks for your time.

Regards,
Vennela