Re: [PATCH ath-next v2 1/8] wifi: ath12k: fix out-of-bounds access on TX stats arrays

[Pardeep Kaur <pardeep.kaur@oss.qualcomm.com>]

On 07-08-2026 07:37, Jeff Johnson wrote:
> On 8/6/2026 6:24 AM, Pardeep Kaur wrote:
>> From: Pardeep Kaur <pardeep.kaur@oss.qualcomm.com>
>>
>> The fw_tx_status[], tx_wbm_rel_source[], and tqm_rel_reason[] arrays
>> are indexed directly by values read from hardware without bounds checks.
>> Values at or beyond MAX_FW_TX_STATUS, HAL_WBM_REL_SRC_MODULE_MAX, or
>> MAX_TQM_RELEASE_REASON respectively would write past the end of the
>> arrays causing memory corruption.
>>
>> Add bounds checks using likely() and WARN_ON_ONCE() before incrementing
>> each counter, consistent with the existing pattern used elsewhere in
>> the ath12k codebase.
>>
>> Tested-on: QCN9274 hw2.0 PCI WLAN.WBE.1.6.r1-00402-QCAHKSWPL_SILICONZ-1
>>
>> Fixes: c5c62287e690 ("wifi: ath12k: Add device dp stats support")
>> Signed-off-by: Pardeep Kaur <pardeep.kaur@oss.qualcomm.com>
>> ---
>>   drivers/net/wireless/ath/ath12k/wifi7/dp_tx.c | 15 ++++++++++++---
>>   1 file changed, 12 insertions(+), 3 deletions(-)
>>
>> diff --git a/drivers/net/wireless/ath/ath12k/wifi7/dp_tx.c b/drivers/net/wireless/ath/ath12k/wifi7/dp_tx.c
>> index 587d58eeccfa..632230e77802 100644
>> --- a/drivers/net/wireless/ath/ath12k/wifi7/dp_tx.c
>> +++ b/drivers/net/wireless/ath/ath12k/wifi7/dp_tx.c
>> @@ -582,7 +582,10 @@ ath12k_dp_tx_process_htt_tx_complete(struct ath12k_dp *dp, void *desc,
>>   
>>   	wbm_status = le32_get_bits(status_desc->info0,
>>   				   HTT_TX_WBM_COMP_INFO0_STATUS);
>> -	dp->device_stats.fw_tx_status[wbm_status]++;
>> +	if (likely(wbm_status < MAX_FW_TX_STATUS))
>> +		dp->device_stats.fw_tx_status[wbm_status]++;
>> +	else
>> +		WARN_ON_ONCE(1);
> My review agent tells me this will now double warn since the default: case of
> the switch (wbm_status) that follows will also ath12k_warn()
>
> So for wbm_status warn in one place or the other, but not both
Thanks for the review will handle this
>
>>   
>>   	switch (wbm_status) {
>>   	case HAL_WBM_REL_HTT_TX_COMP_STATUS_OK:
>> @@ -984,11 +987,17 @@ void ath12k_wifi7_dp_tx_completion_handler(struct ath12k_dp *dp, int ring_id)
>>   		/* Find the HAL_WBM_RELEASE_INFO0_REL_SRC_MODULE value */
>>   		buf_rel_source = le32_get_bits(tx_status->info0,
>>   					       HAL_WBM_RELEASE_INFO0_REL_SRC_MODULE);
>> -		dp->device_stats.tx_wbm_rel_source[buf_rel_source]++;
>> +		if (likely(buf_rel_source < HAL_WBM_REL_SRC_MODULE_MAX))
>> +			dp->device_stats.tx_wbm_rel_source[buf_rel_source]++;
>> +		else
>> +			WARN_ON_ONCE(1);
>>   
>>   		rel_status = le32_get_bits(tx_status->info0,
>>   					   HAL_WBM_COMPL_TX_INFO0_TQM_RELEASE_REASON);
>> -		dp->device_stats.tqm_rel_reason[rel_status]++;
>> +		if (likely(rel_status < MAX_TQM_RELEASE_REASON))
>> +			dp->device_stats.tqm_rel_reason[rel_status]++;
>> +		else
>> +			WARN_ON_ONCE(1);
>>   
>>   		/* Release descriptor as soon as extracting necessary info
>>   		 * to reduce contention
>> base-commit: 691e5e43b2aa
>> --
>> 2.34.1