[PATCH -next] drm/msm/adreno: Switch to memdup_user_nul() helper

[Yang Yingliang]

Use memdup_user_nul() helper instead of open-coding to
simplify the code.

Signed-off-by: Yang Yingliang <yangyingliang at huawei.com>
---
 drivers/gpu/drm/msm/adreno/adreno_gpu.c | 14 +++-----------
 1 file changed, 3 insertions(+), 11 deletions(-)

diff --git a/drivers/gpu/drm/msm/adreno/adreno_gpu.c b/drivers/gpu/drm/msm/adreno/adreno_gpu.c
index 382fb7f9e497..50b33e14237b 100644
--- a/drivers/gpu/drm/msm/adreno/adreno_gpu.c
+++ b/drivers/gpu/drm/msm/adreno/adreno_gpu.c
@@ -339,17 +339,9 @@ int adreno_set_param(struct msm_gpu *gpu, struct msm_file_private *ctx,
 	case MSM_PARAM_CMDLINE: {
 		char *str, **paramp;
 
-		str = kmalloc(len + 1, GFP_KERNEL);
-		if (!str)
-			return -ENOMEM;
-
-		if (copy_from_user(str, u64_to_user_ptr(value), len)) {
-			kfree(str);
-			return -EFAULT;
-		}
-
-		/* Ensure string is null terminated: */
-		str[len] = '\0';
+		str = memdup_user_nul(u64_to_user_ptr(value), len);
+		if (IS_ERR(str))
+			return PTR_ERR(str);
 
 		if (param == MSM_PARAM_COMM) {
 			paramp = &ctx->comm;
-- 
2.25.1