On Mon, 13. Jul 20:52, Elizaveta Tereshkina wrote:
> From: Ethan Tidmore <[email protected]>
>
> commit 06277983eca4a31d3c2114fa33d99a6e82484b11 upstream.
>
> The function drm_atomic_get_plane_state() can return an error pointer
> and is not checked for it. Add error pointer check.
>
> Detected by Smatch:
> drivers/gpu/drm/sun4i/sun4i_backend.c:496 sun4i_backend_atomic_check() error:
> 'plane_state' dereferencing possible ERR_PTR()
>
> Fixes: 96180dde23b79 ("drm/sun4i: backend: Add a custom atomic_check for the
> frontend")
> Signed-off-by: Ethan Tidmore <[email protected]>
> Reviewed-by: Chen-Yu Tsai <[email protected]>
> Link: https://patch.msgid.link/[email protected]
> Signed-off-by: Chen-Yu Tsai <[email protected]>
> Signed-off-by: Elizaveta Tereshkina <[email protected]>
> ---
> Backport fix for CVE-2026-53066
> drivers/gpu/drm/sun4i/sun4i_backend.c | 3 +++
> 1 file changed, 3 insertions(+)
>
> diff --git a/drivers/gpu/drm/sun4i/sun4i_backend.c
> b/drivers/gpu/drm/sun4i/sun4i_backend.c
> index d935f36a24dd..b3741827c6c3 100644
> --- a/drivers/gpu/drm/sun4i/sun4i_backend.c
> +++ b/drivers/gpu/drm/sun4i/sun4i_backend.c
> @@ -507,6 +507,9 @@ static int sun4i_backend_atomic_check(struct sunxi_engine
> *engine,
> drm_for_each_plane_mask(plane, drm, crtc_state->plane_mask) {
> struct drm_plane_state *plane_state =
> drm_atomic_get_plane_state(state, plane);
> + if (IS_ERR(plane_state))
> + return PTR_ERR(plane_state);
> +
> struct sun4i_layer_state *layer_state =
> state_to_sun4i_layer_state(plane_state);
> struct drm_framebuffer *fb = plane_state->fb;
This would trigger a really unnecessary build warning due to lack of
commit b5ec6fd286df ("kbuild: Drop -Wdeclaration-after-statement") in
5.10/5.15 kernels.
I wonder if that commit can just be ported to 5.10/5.15. You may consider
it.
Otherwise the current backport should be adapted to avoid declarations
after statements.
