[PATCH] wifi: ath12k: Add NULL check to validate tpc_stats

[Vasanthakumar Thiagarajan]

On 2/21/2025 9:42 AM, Roopni Devanathan wrote:
> While processing TPC stats received from firmware, there are chances that
> the tpc_stats might not be filled and the data is not available. This can
> happen under two scenarios. First, when firmware sends a non-zero event
> count before event count 0. When this happens, tpc_stats will be checked
> for data before memory allocation and the tpc_stats will be unavailable.
> Second, when memory allocation failed when event count received is 0 and
> the firmware still sends a non-zero event. When this happens, memory will
> not be allocated for tpc_stats though event count is 0, so when non-zero
> event count is received, tpc_stats will be empty. There are checks to
> validate if tpc_stats variable is filled that are used in two subsequent
> places, but these are placed after tpc_stats is dereference without
> checking if it is NULL or has valid data.
> 
> Fix this by removing the mentioned checks and adding a NULL check after
> assigning tpc_stats to check if it is valid.
> 
> Tested-on: QCN9274 hw2.0 PCI WLAN.WBE.1.3.1-00173-QCAHKSWPL_SILICONZ-1
> 
> Closes: https://scan7.scan.coverity.com/#/project-view/52668/11354?selectedIssue=1637145
> Fixes: f0c3bb78e42f ("wifi: ath12k: Add Support to Parse TPC Event from Firmware")
> Signed-off-by: Roopni Devanathan <quic_rdevanat at quicinc.com>

Reviewed-by: Vasanthakumar Thiagarajan <vasanthakumar.thiagarajan at oss.qualcomm.com>