Re: [PATCH] drm/nouveau: Fix gem reference leak in validate_init()

From: lyude

Date: Thu Sep 17 2026 - 14:46:57 EST


Reviewed-by: Lyude Paul <lyude@xxxxxxxxxx>

Will push to drm-misc-fixes in a bit

On Wed, 2026-09-16 at 18:02 +0000, Wentao Liang wrote:
> On the ttm_bo_reserve() failure and "vma not found" error paths, the
> loop breaks without adding the looked-up object to any validate list,
> so the reference taken by drm_gem_object_lookup() is never released;
> validate_fini() only walks the spliced lists.  Drop the reference
> before breaking out on both paths.
>
> Fixes: 19ca10d82e33bcfe ("drm/nouveau/gem: lookup VMAs for buffers
> referenced by pushbuf ioctl")
> Cc: stable@xxxxxxxxxxxxxxx
> Signed-off-by: Wentao Liang <vulab@xxxxxxxxxxx>
> ---
>  drivers/gpu/drm/nouveau/nouveau_gem.c | 2 ++
>  1 file changed, 2 insertions(+)
>
> diff --git a/drivers/gpu/drm/nouveau/nouveau_gem.c
> b/drivers/gpu/drm/nouveau/nouveau_gem.c
> index 20dba02d6175..c2601b559947 100644
> --- a/drivers/gpu/drm/nouveau/nouveau_gem.c
> +++ b/drivers/gpu/drm/nouveau/nouveau_gem.c
> @@ -513,6 +513,7 @@ validate_init(struct nouveau_channel *chan,
> struct drm_file *file_priv,
>   if (unlikely(ret)) {
>   if (ret != -ERESTARTSYS)
>   NV_PRINTK(err, cli, "fail
> reserve\n");
> + drm_gem_object_put(gem);
>   break;
>   }
>   }
> @@ -522,6 +523,7 @@ validate_init(struct nouveau_channel *chan,
> struct drm_file *file_priv,
>   struct nouveau_vma *vma =
> nouveau_vma_find(nvbo, vmm);
>   if (!vma) {
>   NV_PRINTK(err, cli, "vma not
> found!\n");
> + drm_gem_object_put(gem);
>   ret = -EINVAL;
>   break;
>   }