Re: [PATCH] accel/ivpu: Reject firmware log with size smaller than header

["Wachowski, Karol" <karol.wachowski@linux.intel.com>]

On 15-Jul-26 9:42, Jhonraushan wrote:
> fw_log_from_bo() validates the tracing buffer header_size and that the
> log fits within the BO, but never checks that log->size is at least
> log->header_size. fw_log_print_buffer() then computes:
> 
>    u32 data_size = log->size - log->header_size;
> 
> which underflows to a near-U32_MAX value when firmware reports a log whose
> size is smaller than its header. That huge data_size defeats the
> log_start/log_end bounds clamps added by commit dd1311bcf0e6 ("accel/ivpu:
> Add bounds checks for firmware log indices"), so fw_log_print_lines() reads
> far past the small real data region of the BO. A size of 0 also makes
> fw_log_from_bo() advance the offset by 0, causing the callers to loop
> forever on the same header.
> 
> Reject logs whose size is smaller than the header (which also rejects
> size == 0).
> 
> Fixes: d4e4257afa6e ("accel/ivpu: Add firmware tracing support")
> Cc: stable@vger.kernel.org
> Signed-off-by: Jhonraushan <raushan.jhon@gmail.com>
> ---
>   drivers/accel/ivpu/ivpu_fw_log.c | 4 ++++
>   1 file changed, 4 insertions(+)
> 
> diff --git a/drivers/accel/ivpu/ivpu_fw_log.c b/drivers/accel/ivpu/ivpu_fw_log.c
> index 275baf844b56..716467aa3156 100644
> --- a/drivers/accel/ivpu/ivpu_fw_log.c
> +++ b/drivers/accel/ivpu/ivpu_fw_log.c
> @@ -43,6 +43,10 @@ static int fw_log_from_bo(struct ivpu_device *vdev, struct ivpu_bo *bo, u32 *off
>   		ivpu_dbg(vdev, FW_BOOT, "Invalid header size 0x%x\n", log->header_size);
>   		return -EINVAL;
>   	}
> +	if (log->size < log->header_size) {
> +		ivpu_dbg(vdev, FW_BOOT, "Invalid log size 0x%x\n", log->size);
> +		return -EINVAL;
> +	}
>   	if ((char *)log + log->size > (char *)ivpu_bo_vaddr(bo) + ivpu_bo_size(bo)) {
>   		ivpu_dbg(vdev, FW_BOOT, "Invalid log size 0x%x\n", log->size);
>   		return -EINVAL;

Thanks for submission.

Reviewed-by: Karol Wachowski <karol.wachowski@linux.intel.com>