2021-09-07 14:10:37

by Alex Xu (Hello71)

Subject: [PATCH] drm/plane-helper: fix uninitialized variable reference

drivers/gpu/drm/drm_plane_helper.c: In function 'drm_primary_helper_update':
drivers/gpu/drm/drm_plane_helper.c:113:32: error: 'visible' is used uninitialized [-Werror=uninitialized]
113 | struct drm_plane_state plane_state = {
| ^~~~~~~~~~~
drivers/gpu/drm/drm_plane_helper.c:178:14: note: 'visible' was declared here
178 | bool visible;
| ^~~~~~~
cc1: all warnings being treated as errors

visible is an output, not an input. in practice this use might turn out
OK but it's still UB.

Fixes: df86af9133 ("drm/plane-helper: Add drm_plane_helper_check_state()")
---
drivers/gpu/drm/drm_plane_helper.c | 1 -
1 file changed, 1 deletion(-)

diff --git a/drivers/gpu/drm/drm_plane_helper.c b/drivers/gpu/drm/drm_plane_helper.c
index 5b2d0ca03705..838b32b70bce 100644
--- a/drivers/gpu/drm/drm_plane_helper.c
+++ b/drivers/gpu/drm/drm_plane_helper.c
@@ -123,7 +123,6 @@ static int drm_plane_helper_check_update(struct drm_plane *plane,
.crtc_w = drm_rect_width(dst),
.crtc_h = drm_rect_height(dst),
.rotation = rotation,
- .visible = *visible,
};
struct drm_crtc_state crtc_state = {
.crtc = crtc,
--
2.33.0

2021-09-08 18:36:57

by Daniel Vetter

Subject: Re: [PATCH] drm/plane-helper: fix uninitialized variable reference

On Tue, Sep 07, 2021 at 10:08:36AM -0400, Alex Xu (Hello71) wrote:
> drivers/gpu/drm/drm_plane_helper.c: In function 'drm_primary_helper_update':
> drivers/gpu/drm/drm_plane_helper.c:113:32: error: 'visible' is used uninitialized [-Werror=uninitialized]
> 113 | struct drm_plane_state plane_state = {
> | ^~~~~~~~~~~
> drivers/gpu/drm/drm_plane_helper.c:178:14: note: 'visible' was declared here
> 178 | bool visible;
> | ^~~~~~~
> cc1: all warnings being treated as errors
>
> visible is an output, not an input. in practice this use might turn out
> OK but it's still UB.
>
> Fixes: df86af9133 ("drm/plane-helper: Add drm_plane_helper_check_state()")

I need a signed-off-by from you before I can merge this. See

https://dri.freedesktop.org/docs/drm/process/submitting-patches.html#sign-your-work-the-developer-s-certificate-of-origin

Patch lgtm otherwise.
-Daniel

> ---
> drivers/gpu/drm/drm_plane_helper.c | 1 -
> 1 file changed, 1 deletion(-)
>
> diff --git a/drivers/gpu/drm/drm_plane_helper.c b/drivers/gpu/drm/drm_plane_helper.c
> index 5b2d0ca03705..838b32b70bce 100644
> --- a/drivers/gpu/drm/drm_plane_helper.c
> +++ b/drivers/gpu/drm/drm_plane_helper.c
> @@ -123,7 +123,6 @@ static int drm_plane_helper_check_update(struct drm_plane *plane,
> .crtc_w = drm_rect_width(dst),
> .crtc_h = drm_rect_height(dst),
> .rotation = rotation,
> - .visible = *visible,
> };
> struct drm_crtc_state crtc_state = {
> .crtc = crtc,
> --
> 2.33.0
>

--
Daniel Vetter
Software Engineer, Intel Corporation
http://blog.ffwll.ch

2021-09-09 01:40:32

by Alex Xu (Hello71)

Subject: [PATCH v2] drm/plane-helper: fix uninitialized variable reference

drivers/gpu/drm/drm_plane_helper.c: In function 'drm_primary_helper_update':
drivers/gpu/drm/drm_plane_helper.c:113:32: error: 'visible' is used uninitialized [-Werror=uninitialized]
113 | struct drm_plane_state plane_state = {
| ^~~~~~~~~~~
drivers/gpu/drm/drm_plane_helper.c:178:14: note: 'visible' was declared here
178 | bool visible;
| ^~~~~~~
cc1: all warnings being treated as errors

visible is an output, not an input. in practice this use might turn out
OK but it's still UB.

Fixes: df86af9133 ("drm/plane-helper: Add drm_plane_helper_check_state()")
Signed-off-by: Alex Xu (Hello71) <[email protected]>
---
drivers/gpu/drm/drm_plane_helper.c | 1 -
1 file changed, 1 deletion(-)

diff --git a/drivers/gpu/drm/drm_plane_helper.c b/drivers/gpu/drm/drm_plane_helper.c
index 5b2d0ca03705..838b32b70bce 100644
--- a/drivers/gpu/drm/drm_plane_helper.c
+++ b/drivers/gpu/drm/drm_plane_helper.c
@@ -123,7 +123,6 @@ static int drm_plane_helper_check_update(struct drm_plane *plane,
.crtc_w = drm_rect_width(dst),
.crtc_h = drm_rect_height(dst),
.rotation = rotation,
- .visible = *visible,
};
struct drm_crtc_state crtc_state = {
.crtc = crtc,
--
2.33.0

2021-09-09 09:36:31

by Simon Ser

Subject: Re: [PATCH v2] drm/plane-helper: fix uninitialized variable reference

Reviewed-by: Simon Ser <[email protected]>