drm/tegra: put drm_gem_object ref on error in tegra_fb_create

Commit Message

Fedor Pchelkin Dec. 15, 2023, 9:33 a.m. UTC

Inside tegra_fb_create(), drm_gem_object_lookup() increments ref count of
the found object. But if the following size check fails then the last
found object's ref count should be put there as the unreferencing loop
can't detect this situation.

Found by Linux Verification Center (linuxtesting.org).

Fixes: de2ba664c30f ("gpu: host1x: drm: Add memory manager and fb")
Signed-off-by: Fedor Pchelkin <[e-mail]>
---
 drivers/gpu/drm/tegra/fb.c | 1 +
 1 file changed, 1 insertion(+)

Patch

diff --git a/drivers/gpu/drm/tegra/fb.c b/drivers/gpu/drm/tegra/fb.c
index a719af1dc9a5..46170753699d 100644
--- a/drivers/gpu/drm/tegra/fb.c
+++ b/drivers/gpu/drm/tegra/fb.c
@@ -159,6 +159,7 @@  struct drm_framebuffer *tegra_fb_create(struct drm_device *drm,
 
 		if (gem->size < size) {
 			err = -EINVAL;
+			drm_gem_object_put(gem);
 			goto unreference;
 		}