[PATCH AUTOSEL 5.4 156/266] drm/msm/mdp5: Fix mdp5_init error path for failed mdp5_kms allocation

From: Sasha Levin
Date: Wed Jun 17 2020 - 21:23:14 EST


From: Roy Spliet <nouveau@xxxxxxxxxx>

[ Upstream commit e4337877c5d578722c0716f131fb774522013cf5 ]

When allocation for mdp5_kms fails, calling mdp5_destroy() leads to undefined
behaviour, likely a nullptr exception or use-after-free troubles.

Signed-off-by: Roy Spliet <nouveau@xxxxxxxxxx>
Reviewed-by: Abhinav Kumar <abhinavk@xxxxxxxxxxxxxx>
Signed-off-by: Rob Clark <robdclark@xxxxxxxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
---
drivers/gpu/drm/msm/disp/mdp5/mdp5_kms.c | 3 ++-
1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/drivers/gpu/drm/msm/disp/mdp5/mdp5_kms.c b/drivers/gpu/drm/msm/disp/mdp5/mdp5_kms.c
index 91cd76a2bab1..77823ccdd0f8 100644
--- a/drivers/gpu/drm/msm/disp/mdp5/mdp5_kms.c
+++ b/drivers/gpu/drm/msm/disp/mdp5/mdp5_kms.c
@@ -1037,7 +1037,8 @@ static int mdp5_init(struct platform_device *pdev, struct drm_device *dev)

return 0;
fail:
- mdp5_destroy(pdev);
+ if (mdp5_kms)
+ mdp5_destroy(pdev);
return ret;
}

--
2.25.1