drm/udl: make control msg static const. (v2)

Thou shall not send control msg from the stack,
does that mean I can send it from the RO memory area?

and it looks like the answer is no, so here's
v2 which kmemdups.

Reported-by: poma
Tested-by: poma <poma@gmail.com>
Signed-off-by: Dave Airlie <airlied@redhat.com>

1 files changed, 11 insertions, 5 deletions

diff --git a/drivers/gpu/drm/udl/udl_main.c b/drivers/gpu/drm/udl/udl_main.c
index 29f0207fa677..873f010d9616 100644
--- a/drivers/gpu/drm/udl/udl_main.c
+++ b/drivers/gpu/drm/udl/udl_main.c
@@ -98,17 +98,23 @@ success:
 static int udl_select_std_channel(struct udl_device *udl)
 {
         int ret;
-        u8 set_def_chn[] = {0x57, 0xCD, 0xDC, 0xA7,
-                            0x1C, 0x88, 0x5E, 0x15,
-                            0x60, 0xFE, 0xC6, 0x97,
-                            0x16, 0x3D, 0x47, 0xF2};
+        static const u8 set_def_chn[] = {0x57, 0xCD, 0xDC, 0xA7,
+                                         0x1C, 0x88, 0x5E, 0x15,
+                                         0x60, 0xFE, 0xC6, 0x97,
+                                         0x16, 0x3D, 0x47, 0xF2};
+        void *sendbuf;
+
+        sendbuf = kmemdup(set_def_chn, sizeof(set_def_chn), GFP_KERNEL);
+        if (!sendbuf)
+                return -ENOMEM;
 
         ret = usb_control_msg(udl->udev,
                               usb_sndctrlpipe(udl->udev, 0),
                               NR_USB_REQUEST_CHANNEL,
                               (USB_DIR_OUT | USB_TYPE_VENDOR), 0, 0,
-                              set_def_chn, sizeof(set_def_chn),
+                              sendbuf, sizeof(set_def_chn),
                               USB_CTRL_SET_TIMEOUT);
+        kfree(sendbuf);
         return ret < 0 ? ret : 0;
 }