[PATCH] virtio-gpu: Use memdup_user() rather than duplicating its implementation

[SF Markus Elfring]

From: Markus Elfring <elfr...@users.sourceforge.net>
Date: Thu, 18 Aug 2016 22:35:14 +0200

Reuse existing functionality from memdup_user() instead of keeping
duplicate source code.

This issue was detected by using the Coccinelle software.

Signed-off-by: Markus Elfring <elfring at users.sourceforge.net>
---
 drivers/gpu/drm/virtio/virtgpu_ioctl.c | 13 ++++---------
 1 file changed, 4 insertions(+), 9 deletions(-)

diff --git a/drivers/gpu/drm/virtio/virtgpu_ioctl.c 
b/drivers/gpu/drm/virtio/virtgpu_ioctl.c
index c046903..512e7cd 100644
--- a/drivers/gpu/drm/virtio/virtgpu_ioctl.c
+++ b/drivers/gpu/drm/virtio/virtgpu_ioctl.c
@@ -152,15 +152,10 @@ static int virtio_gpu_execbuffer(struct drm_device *dev,
        if (ret)
                goto out_free;

-       buf = kmalloc(exbuf->size, GFP_KERNEL);
-       if (!buf) {
-               ret = -ENOMEM;
-               goto out_unresv;
-       }
-       if (copy_from_user(buf, (void __user *)(uintptr_t)exbuf->command,
-                          exbuf->size)) {
-               kfree(buf);
-               ret = -EFAULT;
+       buf = memdup_user((void __user *)(uintptr_t)exbuf->command,
+                         exbuf->size);
+       if (IS_ERR(buf)) {
+               ret = PTR_ERR(buf);
                goto out_unresv;
        }
        virtio_gpu_cmd_submit(vgdev, buf, exbuf->size,
-- 
2.9.3