Re: [PATCH] drm/msm: fix leaks if initialization fails

[Doug Anderson]

Hi,

On Mon, Mar 9, 2020 at 3:14 AM Pavel Machek <pavel@xxxxxxx> wrote:
>
> We should free resources in unlikely case of allocation failure.
>
> Signed-off-by: Pavel Machek <pavel@xxxxxxx>
>
> ---
>
> > Can you submit a patch to fix it?
>
> Here it is.
>
> Best regards,
>                                                                 Pavel
>
>
> diff --git a/drivers/gpu/drm/msm/msm_drv.c b/drivers/gpu/drm/msm/msm_drv.c
> index 83a0000eecb3..f5c1495cc4b9 100644
> --- a/drivers/gpu/drm/msm/msm_drv.c
> +++ b/drivers/gpu/drm/msm/msm_drv.c
> @@ -444,8 +444,10 @@ static int msm_drm_init(struct device *dev, struct drm_driver *drv)
>         if (!dev->dma_parms) {
>                 dev->dma_parms = devm_kzalloc(dev, sizeof(*dev->dma_parms),
>                                               GFP_KERNEL);
> -               if (!dev->dma_parms)
> -                       return -ENOMEM;
> +               if (!dev->dma_parms) {
> +                       ret = -ENOMEM;
> +                       goto err_msm_uninit;
> +               }
>         }
>         dma_set_max_seg_size(dev, DMA_BIT_MASK(32));

Looks good.  Error cases both above and below your "goto" both already
go to err_msm_uninit(), so it makes sense it would also be the
appropriate place for you to go to.  ...and no extra cleanup was
needed for dma_parms allocation since it was devm.  Thus:

Fixes: db735fc4036b ("drm/msm: Set dma maximum segment size for mdss")
Reviewed-by: Douglas Anderson <dianders@xxxxxxxxxxxx>

Thanks for noticing and fixing!

-Doug