Re: [Nouveau] [PATCH] drm/nouveau/secboot: fix some error handling in 'ls_ucode_img_load_gr'

From: Emil Velikov
Date: Mon May 08 2017 - 05:46:09 EST


Hi Christophe,

s/fix some error handling in 'ls_ucode_img_load_gr/plug memory leak in
ls_ucode_img_load_gr() error path/

On 8 May 2017 at 08:46, Christophe JAILLET
<christophe.jaillet@xxxxxxxxxx> wrote:
> The last goto looks spurious because it releases less resources than the
> previous one.
> Add a new label in order to free the memory allocated by the 'kmemdup'
> call.
>
> Fixes: 9d896f3e41a6 ("drm/nouveau/secboot: abstract LS firmware loading functions")
>
> Signed-off-by: Christophe JAILLET <christophe.jaillet@xxxxxxxxxx>
> ---
> This fix is just a guess. I don't have the hardware to test it.
> At first, I just wanted to change the last 'goto free_data' into a
> 'goto free_img' in order to have a 'logical' goto layout.
> Then, I changed my mind and added another label to revert the 'kmemdup' a
> few lines above.
>
> I hope I'm correct :)
Coffee hasn't kicked in fully, but I think this is off. This free()
will be called even on success leading to issues.

> ---
> drivers/gpu/drm/nouveau/nvkm/subdev/secboot/ls_ucode_gr.c | 5 ++++-
> 1 file changed, 4 insertions(+), 1 deletion(-)
>
> diff --git a/drivers/gpu/drm/nouveau/nvkm/subdev/secboot/ls_ucode_gr.c b/drivers/gpu/drm/nouveau/nvkm/subdev/secboot/ls_ucode_gr.c
> index d1cf02d22db1..1b83e1395c34 100644
> --- a/drivers/gpu/drm/nouveau/nvkm/subdev/secboot/ls_ucode_gr.c
> +++ b/drivers/gpu/drm/nouveau/nvkm/subdev/secboot/ls_ucode_gr.c
> @@ -116,6 +116,7 @@ ls_ucode_img_load_gr(const struct nvkm_subdev *subdev, struct ls_ucode_img *img,
> ret = nvkm_firmware_get(subdev->device, f, &sig);
> if (ret)
> goto free_data;
> +
> img->sig = kmemdup(sig->data, sig->size, GFP_KERNEL);
> if (!img->sig) {
> ret = -ENOMEM;
> @@ -127,10 +128,12 @@ ls_ucode_img_load_gr(const struct nvkm_subdev *subdev, struct ls_ucode_img *img,
> &img->ucode_desc);
> if (IS_ERR(img->ucode_data)) {
> ret = PTR_ERR(img->ucode_data);
> - goto free_data;
> + goto free_img_sig;
Thus I'd just move the free here and use goto free_sig.

Regards,
Emil