Re: [PATCH] hw/display/xlnx_dp: fix overflow in xlnx_dp_aux_push_tx_fifo()

[Alistair Francis]

On Mon, Jan 9, 2023 at 4:01 PM Qiang Liu <cyruscyliu@gmail.com> wrote:
>
> This patch checks if the s->tx_fifo is full.
>
> Fixes: 58ac482a66de ("introduce xlnx-dp")
> Resolves: https://gitlab.com/qemu-project/qemu/-/issues/1424
> Reported-by: Qiang Liu <cyruscyliu@gmail.com>
> Signed-off-by: Qiang Liu <cyruscyliu@gmail.com>

Reviewed-by: Alistair Francis <alistair.francis@wdc.com>

Alistair

> ---
>  hw/display/xlnx_dp.c | 6 +++++-
>  1 file changed, 5 insertions(+), 1 deletion(-)
>
> diff --git a/hw/display/xlnx_dp.c b/hw/display/xlnx_dp.c
> index 972473d94f..617b394af2 100644
> --- a/hw/display/xlnx_dp.c
> +++ b/hw/display/xlnx_dp.c
> @@ -854,7 +854,11 @@ static void xlnx_dp_write(void *opaque, hwaddr offset, 
> uint64_t value,
>          break;
>      case DP_AUX_WRITE_FIFO: {
>          uint8_t c = value;
> -        xlnx_dp_aux_push_tx_fifo(s, &c, 1);
> +        if (fifo8_is_full(&s->tx_fifo)) {
> +            qemu_log_mask(LOG_GUEST_ERROR, "xlnx_dp: TX fifo is full");
> +        } else {
> +            xlnx_dp_aux_push_tx_fifo(s, &c, 1);
> +        }
>          break;
>      }
>      case DP_AUX_CLOCK_DIVIDER:
> --
> 2.25.1
>
>