This is a note to let you know that I've just added the patch titled
sch_htb: Fail on unsupported parameters when offload is requested
to the 5.16-stable tree which can be found at:
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary
The filename of the patch is:
sch_htb-fail-on-unsupported-parameters-when-offload-.patch
and it can be found in the queue-5.16 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.
commit 3d062b6ad0f7b2b8b87e3d43bb561890ae6006c8
Author: Maxim Mikityanskiy <maximmi@xxxxxxxxxx>
Date: Tue Jan 25 12:06:54 2022 +0200
sch_htb: Fail on unsupported parameters when offload is requested
[ Upstream commit 429c3be8a5e2695b5b92a6a12361eb89eb185495 ]
The current implementation of HTB offload doesn't support some
parameters. Instead of ignoring them, actively return the EINVAL error
when they are set to non-defaults.
As this patch goes to stable, the driver API is not changed here. If
future drivers support more offload parameters, the checks can be moved
to the driver side.
Note that the buffer and cbuffer parameters are also not supported, but
the tc userspace tool assigns some default values derived from rate and
ceil, and identifying these defaults in sch_htb would be unreliable, so
they are still ignored.
Fixes: d03b195b5aa0 ("sch_htb: Hierarchical QoS hardware offload")
Reported-by: Jakub Kicinski <kuba@xxxxxxxxxx>
Signed-off-by: Maxim Mikityanskiy <maximmi@xxxxxxxxxx>
Reviewed-by: Tariq Toukan <tariqt@xxxxxxxxxx>
Link: https://lore.kernel.org/r/20220125100654.424570-1-maximmi@xxxxxxxxxx
Signed-off-by: Jakub Kicinski <kuba@xxxxxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
diff --git a/net/sched/sch_htb.c b/net/sched/sch_htb.c
index 9267922ea9c37..23a9d6242429f 100644
--- a/net/sched/sch_htb.c
+++ b/net/sched/sch_htb.c
@@ -1810,6 +1810,26 @@ static int htb_change_class(struct Qdisc *sch, u32 classid,
if (!hopt->rate.rate || !hopt->ceil.rate)
goto failure;
+ if (q->offload) {
+ /* Options not supported by the offload. */
+ if (hopt->rate.overhead || hopt->ceil.overhead) {
+ NL_SET_ERR_MSG(extack, "HTB offload doesn't support the overhead parameter");
+ goto failure;
+ }
+ if (hopt->rate.mpu || hopt->ceil.mpu) {
+ NL_SET_ERR_MSG(extack, "HTB offload doesn't support the mpu parameter");
+ goto failure;
+ }
+ if (hopt->quantum) {
+ NL_SET_ERR_MSG(extack, "HTB offload doesn't support the quantum parameter");
+ goto failure;
+ }
+ if (hopt->prio) {
+ NL_SET_ERR_MSG(extack, "HTB offload doesn't support the prio parameter");
+ goto failure;
+ }
+ }
+
/* Keeping backward compatible with rate_table based iproute2 tc */
if (hopt->rate.linklayer == TC_LINKLAYER_UNAWARE)
qdisc_put_rtab(qdisc_get_rtab(&hopt->rate, tb[TCA_HTB_RTAB],
