From: hyesoo.yu <hyesoo.yu@samsung.com>
Date: Fri, 8 Sep 2017 05:33:48 +0000 (+0900)
Subject: [COMMON] g2d: fix to access the NULL pointer
X-Git-Url: https://git.stricted.de/?a=commitdiff_plain;h=c4e7d5040d5eacb8a471dbf316c368a016aa92c8;p=GitHub%2FLineageOS%2Fandroid_kernel_motorola_exynos9610.git

[COMMON] g2d: fix to access the NULL pointer

Fix referencing a pointer that might be null &mm->mmap_sem
when calling down_read

Change-Id: I5e960fac24e6218f0ef71fe33d8e72bfa119d268
Signed-off-by: hyesoo.yu <hyesoo.yu@samsung.com>
---

diff --git a/drivers/gpu/exynos/g2d/g2d_uapi_process.c b/drivers/gpu/exynos/g2d/g2d_uapi_process.c
index 41f874c9b36e..f7b74ee46eaf 100644
--- a/drivers/gpu/exynos/g2d/g2d_uapi_process.c
+++ b/drivers/gpu/exynos/g2d/g2d_uapi_process.c
@@ -310,6 +310,8 @@ static int g2d_get_userptr(struct g2d_task *task,
 	int prot = IOMMU_READ;
 
 	mm = get_task_mm(current);
+	if (!mm)
+		return ret;
 
 	down_read(&mm->mmap_sem);