From: Guenter Roeck <linux@roeck-us.net>
Date: Tue, 13 Jan 2015 05:12:17 +0000 (-0800)
Subject: next: drm/atomic: Use copy_from_user to copy 64 bit data from user space
X-Git-Url: http://git.lede-project.org./?a=commitdiff_plain;h=42c5814c9c9828a7fcbe25f69c5c8cbbf29ed957;p=openwrt%2Fstaging%2Fblogic.git

next: drm/atomic: Use copy_from_user to copy 64 bit data from user space

Copying 64 bit data from user space using get_user is not supported
on all architectures, and may result in the following build error.

ERROR: "__get_user_bad" [drivers/gpu/drm/drm.ko] undefined!

Avoid the problem by using copy_from_user.

Fixes: d34f20d6e2f2 ("drm: Atomic modeset ioctl")
Cc: Rob Clark <robdclark@gmail.com>
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
---

diff --git a/drivers/gpu/drm/drm_atomic.c b/drivers/gpu/drm/drm_atomic.c
index 1e38dfc8e462..af3f3dfdb49f 100644
--- a/drivers/gpu/drm/drm_atomic.c
+++ b/drivers/gpu/drm/drm_atomic.c
@@ -1259,7 +1259,9 @@ retry:
 				goto fail;
 			}
 
-			if (get_user(prop_value, prop_values_ptr + copied_props)) {
+			if (copy_from_user(&prop_value,
+					   prop_values_ptr + copied_props,
+					   sizeof(prop_value))) {
 				ret = -EFAULT;
 				goto fail;
 			}