From 32e5a120a5105bce01561978ee55aee8e40ac0dc Mon Sep 17 00:00:00 2001
From: Fedor Pchelkin <pchelkin@ispras.ru>
Date: Fri, 15 Dec 2023 12:33:55 +0300
Subject: [PATCH] drm/tegra: put drm_gem_object ref on error in tegra_fb_create
Git-commit: 32e5a120a5105bce01561978ee55aee8e40ac0dc
Patch-mainline: v6.9-rc1
References: git-fixes

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 <pchelkin@ispras.ru>
Signed-off-by: Thierry Reding <treding@nvidia.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20231215093356.12067-1-pchelkin@ispras.ru
Acked-by: Takashi Iwai <tiwai@suse.de>

---
 drivers/gpu/drm/tegra/fb.c | 1 +
 1 file changed, 1 insertion(+)

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;
 		}
 
-- 
2.43.0