From: Roy Spliet <nouveau@spliet.org>
Date: Tue, 7 Apr 2020 17:07:37 +0000 (+0100)
Subject: drm/msm/mdp5: Fix mdp5_init error path for failed mdp5_kms allocation
X-Git-Tag: v5.4.49~160
X-Git-Url: https://www.infradead.org/git/?a=commitdiff_plain;h=f1069001bba71708128a61c29903a5c84a302296;p=users%2Fdwmw2%2Flinux.git

drm/msm/mdp5: Fix mdp5_init error path for failed mdp5_kms allocation

[ 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@spliet.org>
Reviewed-by: Abhinav Kumar <abhinavk@codeaurora.org>
Signed-off-by: Rob Clark <robdclark@chromium.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---

diff --git a/drivers/gpu/drm/msm/disp/mdp5/mdp5_kms.c b/drivers/gpu/drm/msm/disp/mdp5/mdp5_kms.c
index 91cd76a2bab11..77823ccdd0f8f 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;
 }