[PATCH net-next] net: qede: flower: validate control flags

[PATCH net-next] net: qede: flower: validate control flags

[Asbjørn Sloth Tønnesen]

This driver currently doesn't support any flower control flags.

Implement check for control flags, such as can be set through
`tc flower ... ip_flags frag`.

Since qede_parse_flow_attr() are called by both qede_add_tc_flower_fltr()
and qede_flow_spec_to_rule(), as the latter doesn't having access to
extack, then flow_rule_*_control_flags() can't be used in this driver.

This patch therefore re-implements flow_rule_match_has_control_flags(),
but with error messaging via DP_NOTICE, instead of NL_SET_ERR_MSG_FMT_MOD.

So in case any control flags are masked, we call DP_NOTICE() and
return -EOPNOTSUPP.

Only compile-tested.

Signed-off-by: Asbjørn Sloth Tønnesen <ast@fiberby.net>
---

This is AFAICT the last driver which didn't validate these flags.

$ git grep FLOW_DISSECTOR_KEY_CONTROL drivers/
$ git grep 'flow_rule_.*_control_flags' drivers/

 drivers/net/ethernet/qlogic/qede/qede_filter.c | 13 +++++++++++++
 1 file changed, 13 insertions(+)

diff --git a/drivers/net/ethernet/qlogic/qede/qede_filter.c b/drivers/net/ethernet/qlogic/qede/qede_filter.c
index a5ac21a0ee33..40f72e700d8e 100644
--- a/drivers/net/ethernet/qlogic/qede/qede_filter.c
+++ b/drivers/net/ethernet/qlogic/qede/qede_filter.c
@@ -1843,6 +1843,19 @@ qede_parse_flow_attr(struct qede_dev *edev, __be16 proto,
 		return -EPROTONOSUPPORT;
 	}
 
+	if (flow_rule_match_key(rule, FLOW_DISSECTOR_KEY_CONTROL)) {
+		struct flow_match_control match;
+
+		flow_rule_match_control(rule, &match);
+
+		if (match.mask->flags) {
+			DP_NOTICE(edev,
+				  "Unsupported match on control.flags %#x",
+				  match.mask->flags);
+			return -EOPNOTSUPP;
+		}
+	}
+
 	if (flow_rule_match_key(rule, FLOW_DISSECTOR_KEY_BASIC)) {
 		struct flow_match_basic match;
 
-- 
2.43.0

Re: [PATCH net-next] net: qede: flower: validate control flags

[Jiri Pirko]

Wed, Apr 24, 2024 at 03:42:48PM CEST, ast@fiberby.net wrote:
>This driver currently doesn't support any flower control flags.
>
>Implement check for control flags, such as can be set through
>`tc flower ... ip_flags frag`.
>
>Since qede_parse_flow_attr() are called by both qede_add_tc_flower_fltr()
>and qede_flow_spec_to_rule(), as the latter doesn't having access to
>extack, then flow_rule_*_control_flags() can't be used in this driver.

Why? You can pass null.

>
>This patch therefore re-implements flow_rule_match_has_control_flags(),
>but with error messaging via DP_NOTICE, instead of NL_SET_ERR_MSG_FMT_MOD.
>
>So in case any control flags are masked, we call DP_NOTICE() and
>return -EOPNOTSUPP.
>
>Only compile-tested.
>
>Signed-off-by: Asbjørn Sloth Tønnesen <ast@fiberby.net>
>---
>
>This is AFAICT the last driver which didn't validate these flags.
>
>$ git grep FLOW_DISSECTOR_KEY_CONTROL drivers/
>$ git grep 'flow_rule_.*_control_flags' drivers/
>
> drivers/net/ethernet/qlogic/qede/qede_filter.c | 13 +++++++++++++
> 1 file changed, 13 insertions(+)
>
>diff --git a/drivers/net/ethernet/qlogic/qede/qede_filter.c b/drivers/net/ethernet/qlogic/qede/qede_filter.c
>index a5ac21a0ee33..40f72e700d8e 100644
>--- a/drivers/net/ethernet/qlogic/qede/qede_filter.c
>+++ b/drivers/net/ethernet/qlogic/qede/qede_filter.c
>@@ -1843,6 +1843,19 @@ qede_parse_flow_attr(struct qede_dev *edev, __be16 proto,
> 		return -EPROTONOSUPPORT;
> 	}
> 
>+	if (flow_rule_match_key(rule, FLOW_DISSECTOR_KEY_CONTROL)) {
>+		struct flow_match_control match;
>+
>+		flow_rule_match_control(rule, &match);
>+
>+		if (match.mask->flags) {
>+			DP_NOTICE(edev,
>+				  "Unsupported match on control.flags %#x",
>+				  match.mask->flags);
>+			return -EOPNOTSUPP;
>+		}
>+	}
>+
> 	if (flow_rule_match_key(rule, FLOW_DISSECTOR_KEY_BASIC)) {
> 		struct flow_match_basic match;
> 
>-- 
>2.43.0
>
>

Re: [PATCH net-next] net: qede: flower: validate control flags

[Asbjørn Sloth Tønnesen]

Hi Jiri,

On 4/24/24 2:52 PM, Jiri Pirko wrote:
> Wed, Apr 24, 2024 at 03:42:48PM CEST, ast@fiberby.net wrote:
>> This driver currently doesn't support any flower control flags.
>>
>> Implement check for control flags, such as can be set through
>> `tc flower ... ip_flags frag`.
>>
>> Since qede_parse_flow_attr() are called by both qede_add_tc_flower_fltr()
>> and qede_flow_spec_to_rule(), as the latter doesn't having access to
>> extack, then flow_rule_*_control_flags() can't be used in this driver.
> 
> Why? You can pass null.

Ah, I see. I hadn't traced that option down through the defines,
I incorrectly assumed that NL_SET_ERR_MSG* didn't allow NULL.

Currently thinking about doing v2 in this style:

if (flow_rule_match_has_control_flags(rule, extack)) {
         if (!extack)
                 DP_NOTICE(edev, "Unsupported match on control.flags");
         return -EOPNOTSUPP;
}

pw-bot: changes-requested

-- 
Best regards
Asbjørn Sloth Tønnesen
Network Engineer
Fiberby - AS42541

Re: [PATCH net-next] net: qede: flower: validate control flags

[Jiri Pirko]

Wed, Apr 24, 2024 at 06:43:14PM CEST, ast@fiberby.net wrote:
>Hi Jiri,
>
>On 4/24/24 2:52 PM, Jiri Pirko wrote:
>> Wed, Apr 24, 2024 at 03:42:48PM CEST, ast@fiberby.net wrote:
>> > This driver currently doesn't support any flower control flags.
>> > 
>> > Implement check for control flags, such as can be set through
>> > `tc flower ... ip_flags frag`.
>> > 
>> > Since qede_parse_flow_attr() are called by both qede_add_tc_flower_fltr()
>> > and qede_flow_spec_to_rule(), as the latter doesn't having access to
>> > extack, then flow_rule_*_control_flags() can't be used in this driver.
>> 
>> Why? You can pass null.
>
>Ah, I see. I hadn't traced that option down through the defines,
>I incorrectly assumed that NL_SET_ERR_MSG* didn't allow NULL.
>
>Currently thinking about doing v2 in this style:
>
>if (flow_rule_match_has_control_flags(rule, extack)) {
>        if (!extack)
>                DP_NOTICE(edev, "Unsupported match on control.flags");
>        return -EOPNOTSUPP;
>}

Looks ok.

>
>pw-bot: changes-requested
>
>-- 
>Best regards
>Asbjørn Sloth Tønnesen
>Network Engineer
>Fiberby - AS42541