Re: [PATCH] accel/ivpu: Fix signed integer truncation in IPC receive

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

On 29-May-26 13:54, Andrzej Kacprowski wrote:
> Fix potential buffer overflow where firmware-supplied data_size is cast
> to signed int before being used in min_t(). Large unsigned values
> (>= 0x80000000) become negative, causing unsigned wraparound and
> oversized memcpy operations that can overflow the stack buffer.
> 
> Change min_t(int, ...) to min_t(u32, ...) to ensure large values are
> properly clamped instead of becoming negative.
> 
> Fixes: 3b434a3445ff ("accel/ivpu: Use threaded IRQ to handle JOB done messages")
> Cc: <stable@vger.kernel.org> # v6.18+
> Signed-off-by: Andrzej Kacprowski <andrzej.kacprowski@linux.intel.com>

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

> ---
>   drivers/accel/ivpu/ivpu_ipc.c | 2 +-
>   1 file changed, 1 insertion(+), 1 deletion(-)
> 
> diff --git a/drivers/accel/ivpu/ivpu_ipc.c b/drivers/accel/ivpu/ivpu_ipc.c
> index f47df092bb0d..9980a7898bed 100644
> --- a/drivers/accel/ivpu/ivpu_ipc.c
> +++ b/drivers/accel/ivpu/ivpu_ipc.c
> @@ -276,7 +276,7 @@ int ivpu_ipc_receive(struct ivpu_device *vdev, struct ivpu_ipc_consumer *cons,
>   	if (ipc_buf)
>   		memcpy(ipc_buf, rx_msg->ipc_hdr, sizeof(*ipc_buf));
>   	if (rx_msg->jsm_msg) {
> -		u32 size = min_t(int, rx_msg->ipc_hdr->data_size, sizeof(*jsm_msg));
> +		u32 size = min_t(u32, rx_msg->ipc_hdr->data_size, sizeof(*jsm_msg));
>   
>   		if (rx_msg->jsm_msg->result != VPU_JSM_STATUS_SUCCESS) {
>   			ivpu_err(vdev, "IPC resp result error: %d\n", rx_msg->jsm_msg->result);