[PATCH net-next] net/sched: taprio: align entry index attr validation with mqprio

[PATCH net-next] net/sched: taprio: align entry index attr validation with mqprio

[Simon Horman]

Both taprio and mqprio have code to validate respective entry index
attributes. The validation is indented to ensure that the attribute is
present, and that it's value is in range, and that each value is only
used once.

The purpose of this patch is to align the implementation of taprio with
that of mqprio as there seems to be no good reason for them to differ.
For one thing, this way, bugs will be present in both or neither.

As a follow-up some consideration could be given to a common function
used by both sch.

No functional change intended.

Except of tdc run: the results of the taprio tests

  # ok 81 ba39 - Add taprio Qdisc to multi-queue device (8 queues)
  # ok 82 9462 - Add taprio Qdisc with multiple sched-entry
  # ok 83 8d92 - Add taprio Qdisc with txtime-delay
  # ok 84 d092 - Delete taprio Qdisc with valid handle
  # ok 85 8471 - Show taprio class
  # ok 86 0a85 - Add taprio Qdisc to single-queue device
  # ok 87 6f62 - Add taprio Qdisc with too short interval
  # ok 88 831f - Add taprio Qdisc with too short cycle-time
  # ok 89 3e1e - Add taprio Qdisc with an invalid cycle-time
  # ok 90 39b4 - Reject grafting taprio as child qdisc of software taprio
  # ok 91 e8a1 - Reject grafting taprio as child qdisc of offloaded taprio
  # ok 92 a7bf - Graft cbs as child of software taprio
  # ok 93 6a83 - Graft cbs as child of offloaded taprio

Cc: Vladimir Oltean <vladimir.oltean@nxp.com>
Cc: Maher Azzouzi <maherazz04@gmail.com>
Link: https://lore.kernel.org/netdev/20250723125521.GA2459@horms.kernel.org/
Signed-off-by: Simon Horman <horms@kernel.org>
---
 net/sched/sch_taprio.c | 12 ++++--------
 1 file changed, 4 insertions(+), 8 deletions(-)

diff --git a/net/sched/sch_taprio.c b/net/sched/sch_taprio.c
index 2b14c81a87e5..e759e43ad27e 100644
--- a/net/sched/sch_taprio.c
+++ b/net/sched/sch_taprio.c
@@ -998,7 +998,7 @@ static const struct nla_policy entry_policy[TCA_TAPRIO_SCHED_ENTRY_MAX + 1] = {
 
 static const struct nla_policy taprio_tc_policy[TCA_TAPRIO_TC_ENTRY_MAX + 1] = {
 	[TCA_TAPRIO_TC_ENTRY_INDEX]	   = NLA_POLICY_MAX(NLA_U32,
-							    TC_QOPT_MAX_QUEUE),
+							    TC_QOPT_MAX_QUEUE - 1),
 	[TCA_TAPRIO_TC_ENTRY_MAX_SDU]	   = { .type = NLA_U32 },
 	[TCA_TAPRIO_TC_ENTRY_FP]	   = NLA_POLICY_RANGE(NLA_U32,
 							      TC_FP_EXPRESS,
@@ -1698,19 +1698,15 @@ static int taprio_parse_tc_entry(struct Qdisc *sch,
 	if (err < 0)
 		return err;
 
-	if (!tb[TCA_TAPRIO_TC_ENTRY_INDEX]) {
+	if (NL_REQ_ATTR_CHECK(extack, opt, tb, TCA_TAPRIO_TC_ENTRY_INDEX)) {
 		NL_SET_ERR_MSG_MOD(extack, "TC entry index missing");
 		return -EINVAL;
 	}
 
 	tc = nla_get_u32(tb[TCA_TAPRIO_TC_ENTRY_INDEX]);
-	if (tc >= TC_QOPT_MAX_QUEUE) {
-		NL_SET_ERR_MSG_MOD(extack, "TC entry index out of range");
-		return -ERANGE;
-	}
-
 	if (*seen_tcs & BIT(tc)) {
-		NL_SET_ERR_MSG_MOD(extack, "Duplicate TC entry");
+		NL_SET_ERR_MSG_ATTR(extack, tb[TCA_TAPRIO_TC_ENTRY_INDEX],
+				    "Duplicate tc entry");
 		return -EINVAL;
 	}
 

Re: [PATCH net-next] net/sched: taprio: align entry index attr validation with mqprio

[Cong Wang]

On Fri, Jul 25, 2025 at 10:56:47AM +0100, Simon Horman wrote:
> Both taprio and mqprio have code to validate respective entry index
> attributes. The validation is indented to ensure that the attribute is
> present, and that it's value is in range, and that each value is only
> used once.
> 
> The purpose of this patch is to align the implementation of taprio with
> that of mqprio as there seems to be no good reason for them to differ.
> For one thing, this way, bugs will be present in both or neither.
> 
> As a follow-up some consideration could be given to a common function
> used by both sch.
> 
> No functional change intended.
> 
> Except of tdc run: the results of the taprio tests
> 
>   # ok 81 ba39 - Add taprio Qdisc to multi-queue device (8 queues)
>   # ok 82 9462 - Add taprio Qdisc with multiple sched-entry
>   # ok 83 8d92 - Add taprio Qdisc with txtime-delay
>   # ok 84 d092 - Delete taprio Qdisc with valid handle
>   # ok 85 8471 - Show taprio class
>   # ok 86 0a85 - Add taprio Qdisc to single-queue device
>   # ok 87 6f62 - Add taprio Qdisc with too short interval
>   # ok 88 831f - Add taprio Qdisc with too short cycle-time
>   # ok 89 3e1e - Add taprio Qdisc with an invalid cycle-time
>   # ok 90 39b4 - Reject grafting taprio as child qdisc of software taprio
>   # ok 91 e8a1 - Reject grafting taprio as child qdisc of offloaded taprio
>   # ok 92 a7bf - Graft cbs as child of software taprio
>   # ok 93 6a83 - Graft cbs as child of offloaded taprio
> 
> Cc: Vladimir Oltean <vladimir.oltean@nxp.com>
> Cc: Maher Azzouzi <maherazz04@gmail.com>
> Link: https://lore.kernel.org/netdev/20250723125521.GA2459@horms.kernel.org/
> Signed-off-by: Simon Horman <horms@kernel.org>

Reviewed-by: Cong Wang <xiyou.wangcong@gmail.com>

Thanks.

Re: [PATCH net-next] net/sched: taprio: align entry index attr validation with mqprio

[Vinicius Costa Gomes]

Simon Horman <horms@kernel.org> writes:

> Both taprio and mqprio have code to validate respective entry index
> attributes. The validation is indented to ensure that the attribute is
> present, and that it's value is in range, and that each value is only
> used once.
>
> The purpose of this patch is to align the implementation of taprio with
> that of mqprio as there seems to be no good reason for them to differ.
> For one thing, this way, bugs will be present in both or neither.
>
> As a follow-up some consideration could be given to a common function
> used by both sch.
>
> No functional change intended.
>
> Except of tdc run: the results of the taprio tests
>
>   # ok 81 ba39 - Add taprio Qdisc to multi-queue device (8 queues)
>   # ok 82 9462 - Add taprio Qdisc with multiple sched-entry
>   # ok 83 8d92 - Add taprio Qdisc with txtime-delay
>   # ok 84 d092 - Delete taprio Qdisc with valid handle
>   # ok 85 8471 - Show taprio class
>   # ok 86 0a85 - Add taprio Qdisc to single-queue device
>   # ok 87 6f62 - Add taprio Qdisc with too short interval
>   # ok 88 831f - Add taprio Qdisc with too short cycle-time
>   # ok 89 3e1e - Add taprio Qdisc with an invalid cycle-time
>   # ok 90 39b4 - Reject grafting taprio as child qdisc of software taprio
>   # ok 91 e8a1 - Reject grafting taprio as child qdisc of offloaded taprio
>   # ok 92 a7bf - Graft cbs as child of software taprio
>   # ok 93 6a83 - Graft cbs as child of offloaded taprio
>
> Cc: Vladimir Oltean <vladimir.oltean@nxp.com>
> Cc: Maher Azzouzi <maherazz04@gmail.com>
> Link: https://lore.kernel.org/netdev/20250723125521.GA2459@horms.kernel.org/
> Signed-off-by: Simon Horman <horms@kernel.org>
> ---

Acked-by: Vinicius Costa Gomes <vinicius.gomes@intel.com>


Cheers,
-- 
Vinicius

Re: [PATCH net-next] net/sched: taprio: align entry index attr validation with mqprio

[patchwork-bot+netdevbpf]

Hello:

This patch was applied to netdev/net-next.git (main)
by Jakub Kicinski <kuba@kernel.org>:

On Fri, 25 Jul 2025 10:56:47 +0100 you wrote:
> Both taprio and mqprio have code to validate respective entry index
> attributes. The validation is indented to ensure that the attribute is
> present, and that it's value is in range, and that each value is only
> used once.
> 
> The purpose of this patch is to align the implementation of taprio with
> that of mqprio as there seems to be no good reason for them to differ.
> For one thing, this way, bugs will be present in both or neither.
> 
> [...]

Here is the summary with links:
  - [net-next] net/sched: taprio: align entry index attr validation with mqprio
    https://git.kernel.org/netdev/net-next/c/c471b90bb332

You are awesome, thank you!
-- 
Deet-doot-dot, I am a bot.
https://korg.docs.kernel.org/patchwork/pwbot.html