Re: [PATCH net-next 02/12] mlxsw: spectrum_span: Ignore VLAN entries not used by the bridge in mirroring

[Vladimir Oltean <vladimir.oltean@nxp.com>]

On Tue, Feb 22, 2022 at 07:16:53PM +0200, Ido Schimmel wrote:
> Only VLAN entries installed on the bridge device itself should be
> considered when checking whether a packet with a specific VLAN can be
> mirrored via a bridge device. VLAN entries only used to keep context
> (i.e., entries with 'BRIDGE_VLAN_INFO_BRENTRY' unset) should be ignored.
> 
> Fix this by preventing mirroring when the VLAN entry does not have the
> 'BRIDGE_VLAN_INFO_BRENTRY' flag set.
> 
> Fixes: ddaff5047003 ("mlxsw: spectrum: remove guards against !BRIDGE_VLAN_INFO_BRENTRY")
> Signed-off-by: Ido Schimmel <idosch@nvidia.com>
> Reviewed-by: Petr Machata <petrm@nvidia.com>
> ---

Sorry, I didn't realize br_vlan_get_info() doesn't have a
br_vlan_should_use() check. Maybe we should add it, for the same
consideration that a !BRENTRY master VLAN is still a data structure
private to the bridge, that shouldn't be revealed to other modules?

Anyway, this works too.

Reviewed-by: Vladimir Oltean <vladimir.oltean@nxp.com>

> Cc: Vladimir Oltean <vladimir.oltean@nxp.com>
> ---
>  drivers/net/ethernet/mellanox/mlxsw/spectrum_span.c | 3 ++-
>  1 file changed, 2 insertions(+), 1 deletion(-)
> 
> diff --git a/drivers/net/ethernet/mellanox/mlxsw/spectrum_span.c b/drivers/net/ethernet/mellanox/mlxsw/spectrum_span.c
> index 5459490c7790..b73466470f75 100644
> --- a/drivers/net/ethernet/mellanox/mlxsw/spectrum_span.c
> +++ b/drivers/net/ethernet/mellanox/mlxsw/spectrum_span.c
> @@ -269,7 +269,8 @@ mlxsw_sp_span_entry_bridge_8021q(const struct net_device *br_dev,
>  
>  	if (!vid && WARN_ON(br_vlan_get_pvid(br_dev, &vid)))
>  		return NULL;
> -	if (!vid || br_vlan_get_info(br_dev, vid, &vinfo))
> +	if (!vid || br_vlan_get_info(br_dev, vid, &vinfo) ||
> +	    !(vinfo.flags & BRIDGE_VLAN_INFO_BRENTRY))
>  		return NULL;
>  
>  	edev = br_fdb_find_port(br_dev, dmac, vid);
> -- 
> 2.33.1
>