[PATCH AUTOSEL for 3.18 41/53] video: fbdev: udlfb: Fix buffer on stack

From: Sasha Levin
Date: Thu Mar 08 2018 - 00:16:05 EST


From: Maksim Salau <maksim.salau@xxxxxxxxx>

[ Upstream commit 45f580c42e5c125d55dbd8099750a1998de3d917 ]

Allocate buffers on HEAP instead of STACK for local array
that is to be sent using usb_control_msg().

Signed-off-by: Maksim Salau <maksim.salau@xxxxxxxxx>
Cc: Bernie Thompson <bernie@xxxxxxxxxxxx>
Cc: Geert Uytterhoeven <geert@xxxxxxxxxxxxxx>
Signed-off-by: Bartlomiej Zolnierkiewicz <b.zolnierkie@xxxxxxxxxxx>
Signed-off-by: Sasha Levin <alexander.levin@xxxxxxxxxxxxx>
---
drivers/video/fbdev/udlfb.c | 14 ++++++++++++--
1 file changed, 12 insertions(+), 2 deletions(-)

diff --git a/drivers/video/fbdev/udlfb.c b/drivers/video/fbdev/udlfb.c
index ef7d23bb2e28..868cba997585 100644
--- a/drivers/video/fbdev/udlfb.c
+++ b/drivers/video/fbdev/udlfb.c
@@ -1490,15 +1490,25 @@ static struct device_attribute fb_device_attrs[] = {
static int dlfb_select_std_channel(struct dlfb_data *dev)
{
int ret;
- u8 set_def_chn[] = { 0x57, 0xCD, 0xDC, 0xA7,
+ void *buf;
+ static const u8 set_def_chn[] = {
+ 0x57, 0xCD, 0xDC, 0xA7,
0x1C, 0x88, 0x5E, 0x15,
0x60, 0xFE, 0xC6, 0x97,
0x16, 0x3D, 0x47, 0xF2 };

+ buf = kmemdup(set_def_chn, sizeof(set_def_chn), GFP_KERNEL);
+
+ if (!buf)
+ return -ENOMEM;
+
ret = usb_control_msg(dev->udev, usb_sndctrlpipe(dev->udev, 0),
NR_USB_REQUEST_CHANNEL,
(USB_DIR_OUT | USB_TYPE_VENDOR), 0, 0,
- set_def_chn, sizeof(set_def_chn), USB_CTRL_SET_TIMEOUT);
+ buf, sizeof(set_def_chn), USB_CTRL_SET_TIMEOUT);
+
+ kfree(buf);
+
return ret;
}

--
2.14.1