On 13/06/2024 21:17, Geert Uytterhoeven wrote:
No implementations of drm_plane_helper_funcs.get_scanout_buffer() fill
in the optional drm_scanout_buffer.set_pixel() member. Hence the member
may contain non-zero garbage, causing a crash when deferencing it during
drm panic.
Fix this by pre-initializing the drm_scanout_buffer object before
calling drm_plane_helper_funcs.get_scanout_buffer().
Good catch, I don't know how I didn't hit this bug before.
Thanks for the fix.
Reviewed-by: Jocelyn Falempe <jfalempe@xxxxxxxxxx>
Fixes: 24d07f114e4ec760 ("drm/panic: Add a set_pixel() callback to drm_scanout_buffer")
Signed-off-by: Geert Uytterhoeven <geert+renesas@xxxxxxxxx>
---
v2:
- New.
---
drivers/gpu/drm/drm_panic.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/drivers/gpu/drm/drm_panic.c b/drivers/gpu/drm/drm_panic.c
index 293d4dcbc80da7ba..fc04ed4e0b399f55 100644
--- a/drivers/gpu/drm/drm_panic.c
+++ b/drivers/gpu/drm/drm_panic.c
@@ -582,7 +582,7 @@ static void draw_panic_dispatch(struct drm_scanout_buffer *sb)
static void draw_panic_plane(struct drm_plane *plane)
{
- struct drm_scanout_buffer sb;
+ struct drm_scanout_buffer sb = { };
int ret;
unsigned long flags;