[PATCH] drm/msm: Fix possible uninitialized access in fbdev

[Thomas Zimmermann]

Do not run drm_fb_helper_unprepare() if fbdev allocation fails. Avoids
access to an uninitialized pointer. Original bug report is at [1].

Reported-by: kernel test robot <l...@intel.com>
Signed-off-by: Thomas Zimmermann <tzimmerm...@suse.de>
Fixes: 3fb1f62f80a1 ("drm/fb-helper: Remove drm_fb_helper_unprepare() from 
drm_fb_helper_fini()")
Link: 
https://lore.kernel.org/oe-kbuild-all/202302220810.9dymwcq8-...@intel.com/ # 1
---
 drivers/gpu/drm/msm/msm_fbdev.c | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/drivers/gpu/drm/msm/msm_fbdev.c b/drivers/gpu/drm/msm/msm_fbdev.c
index c804e5ba682a..d26aa52217ce 100644
--- a/drivers/gpu/drm/msm/msm_fbdev.c
+++ b/drivers/gpu/drm/msm/msm_fbdev.c
@@ -136,13 +136,13 @@ static const struct drm_fb_helper_funcs 
msm_fb_helper_funcs = {
 struct drm_fb_helper *msm_fbdev_init(struct drm_device *dev)
 {
        struct msm_drm_private *priv = dev->dev_private;
-       struct msm_fbdev *fbdev = NULL;
+       struct msm_fbdev *fbdev;
        struct drm_fb_helper *helper;
        int ret;
 
        fbdev = kzalloc(sizeof(*fbdev), GFP_KERNEL);
        if (!fbdev)
-               goto fail;
+               return NULL;
 
        helper = &fbdev->base;
 
-- 
2.39.2