This driver currently doesn't support any control flags.

Use flow_rule_has_control_flags() to check for control flags,
such as can be set through `tc flower ... ip_flags frag`.

In case any control flags are masked, flow_rule_has_control_flags()
sets a NL extended error message, and we return -EOPNOTSUPP.

Only compile-tested.

Signed-off-by: Asbjørn Sloth Tønnesen <ast@fiberby.net>
---
 drivers/net/ethernet/mellanox/mlxsw/spectrum_flower.c | 4 ++++
 1 file changed, 4 insertions(+)

diff --git a/drivers/net/ethernet/mellanox/mlxsw/spectrum_flower.c b/drivers/net/ethernet/mellanox/mlxsw/spectrum_flower.c
index 9fd1ca079258..f07955b5439f 100644
--- a/drivers/net/ethernet/mellanox/mlxsw/spectrum_flower.c
+++ b/drivers/net/ethernet/mellanox/mlxsw/spectrum_flower.c
@@ -595,6 +595,10 @@ static int mlxsw_sp_flower_parse(struct mlxsw_sp *mlxsw_sp,
 
 		flow_rule_match_control(rule, &match);
 		addr_type = match.key->addr_type;
+
+		if (flow_rule_has_control_flags(match.mask->flags,
+						f->common.extack))
+			return -EOPNOTSUPP;
 	}
 
 	if (flow_rule_match_key(rule, FLOW_DISSECTOR_KEY_BASIC)) {
-- 
2.43.0

On Wed, Apr 17, 2024 at 01:51:20PM +0000, Asbjørn Sloth Tønnesen wrote:
> This driver currently doesn't support any control flags.
> 
> Use flow_rule_has_control_flags() to check for control flags,
> such as can be set through `tc flower ... ip_flags frag`.
> 
> In case any control flags are masked, flow_rule_has_control_flags()
> sets a NL extended error message, and we return -EOPNOTSUPP.
> 
> Only compile-tested.
> 
> Signed-off-by: Asbjørn Sloth Tønnesen <ast@fiberby.net>

Reviewed-by: Ido Schimmel <idosch@nvidia.com>
Tested-by: Ido Schimmel <idosch@nvidia.com>

Without patch:

+ tc qdisc add dev swp1 clsact
+ tc filter add dev swp1 ingress pref 1 proto ip flower skip_sw ip_flags frag action drop
+ tc filter add dev swp1 ingress pref 1 proto ip flower skip_sw ip_flags nofrag action drop
+ tc filter add dev swp1 ingress pref 1 proto ip flower skip_sw ip_flags firstfrag action drop
+ tc filter add dev swp1 ingress pref 1 proto ip flower skip_sw ip_flags nofirstfrag action drop

With patch:

+ tc qdisc add dev swp1 clsact
+ tc filter add dev swp1 ingress pref 1 proto ip flower skip_sw ip_flags frag action drop
Error: mlxsw_spectrum: Unsupported match on control.flags 0x1.
We have an error talking to the kernel
+ tc filter add dev swp1 ingress pref 1 proto ip flower skip_sw ip_flags nofrag action drop
Error: mlxsw_spectrum: Unsupported match on control.flags 0x1.
We have an error talking to the kernel
+ tc filter add dev swp1 ingress pref 1 proto ip flower skip_sw ip_flags firstfrag action drop
Error: mlxsw_spectrum: Unsupported match on control.flags 0x2.
We have an error talking to the kernel
+ tc filter add dev swp1 ingress pref 1 proto ip flower skip_sw ip_flags nofirstfrag action drop
Error: mlxsw_spectrum: Unsupported match on control.flags 0x2.
We have an error talking to the kernel

Thanks!

Asbjørn Sloth Tønnesen <ast@fiberby.net> writes:

> This driver currently doesn't support any control flags.
>
> Use flow_rule_has_control_flags() to check for control flags,
> such as can be set through `tc flower ... ip_flags frag`.
>
> In case any control flags are masked, flow_rule_has_control_flags()
> sets a NL extended error message, and we return -EOPNOTSUPP.
>
> Only compile-tested.
>
> Signed-off-by: Asbjørn Sloth Tønnesen <ast@fiberby.net>

Thanks, I'll take this through our regression.

Petr Machata <petrm@nvidia.com> writes:

> Asbjørn Sloth Tønnesen <ast@fiberby.net> writes:
>
>> This driver currently doesn't support any control flags.
>>
>> Use flow_rule_has_control_flags() to check for control flags,
>> such as can be set through `tc flower ... ip_flags frag`.
>>
>> In case any control flags are masked, flow_rule_has_control_flags()
>> sets a NL extended error message, and we return -EOPNOTSUPP.
>>
>> Only compile-tested.
>>
>> Signed-off-by: Asbjørn Sloth Tønnesen <ast@fiberby.net>
>
> Thanks, I'll take this through our regression.

Nothing bombed.

Tested-by: Petr Machata <petrm@nvidia.com>