Re: [PATCH] dmaengine: k3dma: fix off by one

From: Vinod Koul
Date: Fri Sep 30 2016 - 13:53:22 EST


On Wed, Sep 21, 2016 at 10:16:55PM +0200, Vincent Stehlé wrote:
> In k3_of_dma_simple_xlate(), the d->chans[] array has d->dma_requests
> elements so > should be >=.
>
> Fixes: 8e6152bc660e69f5 ("dmaengine: Add hisilicon k3 DMA engine driver")
> Signed-off-by: Vincent Stehlé <vincent.stehle@xxxxxxxxxxx>
> Cc: Zhangfei Gao <zhangfei.gao@xxxxxxxxxx>
> Cc: Vinod Koul <vinod.koul@xxxxxxxxx>
> Cc: stable@xxxxxxxxxxxxxxx

Is it really stable material? Yes it fixes a bug, but how many will notice
this?


> ---
> drivers/dma/k3dma.c | 2 +-
> 1 file changed, 1 insertion(+), 1 deletion(-)
>
> diff --git a/drivers/dma/k3dma.c b/drivers/dma/k3dma.c
> index aabcb79..cd7f67b 100644
> --- a/drivers/dma/k3dma.c
> +++ b/drivers/dma/k3dma.c
> @@ -792,7 +792,7 @@ static struct dma_chan *k3_of_dma_simple_xlate(struct of_phandle_args *dma_spec,
> struct k3_dma_dev *d = ofdma->of_dma_data;
> unsigned int request = dma_spec->args[0];
>
> - if (request > d->dma_requests)
> + if (request >= d->dma_requests)
> return NULL;
>
> return dma_get_slave_channel(&(d->chans[request].vc.chan));
> --
> 2.9.3
>

--
~Vinod