Re: [PATCH v2 2/4] dmaengine: dw-axi-dmac: Fix LLI dump out-of-bounds access

[Frank Li <Frank.li@oss.nxp.com>]

On Tue, Sep 01, 2026 at 02:16:05PM +0800, Jia Wang wrote:
> axi_chan_list_dump_lli() uses the channel-wide descs_allocated count to
> walk the hw_desc[] array of a single transaction. If multiple
> transactions have allocated LLIs, the channel count can exceed the
> transaction-local nr_hw_descs and make the DMA error path read past the
> end of hw_desc[].
>
> Use the descriptor-local nr_hw_descs count when dumping LLIs.
>
> Fixes: ef6fb2d6f1ab ("dmaengine: dw-axi-dmac: simplify descriptor management")
> Signed-off-by: Jia Wang <wangjia@ultrarisc.com>
> ---

Reviewed-by: Frank Li <Frank.Li@nxp.com>

>  drivers/dma/dw-axi-dmac/dw-axi-dmac-platform.c | 5 +----
>  1 file changed, 1 insertion(+), 4 deletions(-)
>
> diff --git a/drivers/dma/dw-axi-dmac/dw-axi-dmac-platform.c b/drivers/dma/dw-axi-dmac/dw-axi-dmac-platform.c
> index 742e08cfab43..61230d2b1c56 100644
> --- a/drivers/dma/dw-axi-dmac/dw-axi-dmac-platform.c
> +++ b/drivers/dma/dw-axi-dmac/dw-axi-dmac-platform.c
> @@ -1052,10 +1052,7 @@ static void axi_chan_dump_lli(struct axi_dma_chan *chan,
>  static void axi_chan_list_dump_lli(struct axi_dma_chan *chan,
>  				   struct axi_dma_desc *desc_head)
>  {
> -	int count = atomic_read(&chan->descs_allocated);
> -	int i;
> -
> -	for (i = 0; i < count; i++)
> +	for (unsigned int i = 0; i < desc_head->nr_hw_descs; i++)
>  		axi_chan_dump_lli(chan, &desc_head->hw_desc[i]);
>  }
>
>
> --
> 2.34.1
>