Re: [PATCH iwl-net v2 2/2] igc: Check VLAN TCI mask

[Simon Horman <horms@kernel.org>]

On Fri, Dec 01, 2023 at 08:50:43AM +0100, Kurt Kanzenbach wrote:
> Currently the driver accepts VLAN TCI steering rules regardless of the
> configured mask. And things might fail silently or with confusing error
> messages to the user.
> 
> There are two ways to handle the VLAN TCI mask:
> 
>  1. Match on the PCP field using a VLAN prio filter
>  2. Match on complete TCI field using a flex filter
> 
> Therefore, add checks and code for that.
> 
> For instance the following rule is invalid and will be converted into a
> VLAN prio rule which is not correct:
> |root@host:~# ethtool -N enp3s0 flow-type ether vlan 0x0001 m 0xf000 \
> |             action 1
> |Added rule with ID 61
> |root@host:~# ethtool --show-ntuple enp3s0
> |4 RX rings available
> |Total 1 rules
> |
> |Filter: 61
> |        Flow Type: Raw Ethernet
> |        Src MAC addr: 00:00:00:00:00:00 mask: FF:FF:FF:FF:FF:FF
> |        Dest MAC addr: 00:00:00:00:00:00 mask: FF:FF:FF:FF:FF:FF
> |        Ethertype: 0x0 mask: 0xFFFF
> |        VLAN EtherType: 0x0 mask: 0xffff
> |        VLAN: 0x1 mask: 0x1fff
> |        User-defined: 0x0 mask: 0xffffffffffffffff
> |        Action: Direct to queue 1
> 
> After:
> |root@host:~# ethtool -N enp3s0 flow-type ether vlan 0x0001 m 0xf000 \
> |             action 1
> |rmgr: Cannot insert RX class rule: Operation not supported
> 
> Fixes: 7991487ecb2d ("igc: Allow for Flex Filters to be installed")
> Signed-off-by: Kurt Kanzenbach <kurt@linutronix.de>
> Acked-by: Vinicius Costa Gomes <vinicius.gomes@intel.com>

Reviewed-by: Simon Horman <horms@kernel.org>