[PATCH net v2 2/2] net: airoha: fix netif_set_real_num_tx_queues for sparse QoS channels

[Simon Horman]

On Fri, Jun 19, 2026 at 01:37:14PM +0200, Lorenzo Bianconi wrote:
> airoha_tc_htb_alloc_leaf_queue() assigns queue IDs based on the channel
> index (opt->qid = AIROHA_NUM_TX_RING + channel), but updates
> real_num_tx_queues with a simple increment (num_tx_queues + 1). When QoS
> channels are allocated sparsely (e.g., channels 0 and 3 without 1 and
> 2), the returned qid can exceed real_num_tx_queues, causing out-of-bounds
> accesses in the networking stack.
> For example, allocating channel 0 then channel 3 results in
> real_num_tx_queues = 34 but qid = 35, which is out of range [0, 34).
> Fix this by computing real_num_tx_queues based on the highest active
> channel index rather than using a simple counter, in both the allocation
> and deletion paths.
> 
> Fixes: ef1ca9271313b ("net: airoha: Add sched HTB offload support")
> Signed-off-by: Lorenzo Bianconi <lorenzo at kernel.org>

Thanks for the update since v1.

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

FTR, there is an AI-generated review of this patch on sashiko.dev.
I do not think that should impede the progress of this patch but
you may want to consider it in the context of follow-up.