Input: usbtouchscreen - don't use DMA on stack

DMA on the stack is not allowed. The buffer must be kmalloced.

Signed-off-by: Oliver Neukum <oneukum@suse.de>
Signed-off-by: Dmitry Torokhov <dtor@mail.ru>

1 files changed, 19 insertions, 12 deletions

diff --git a/drivers/input/touchscreen/usbtouchscreen.c b/drivers/input/touchscreen/usbtouchscreen.c
index 63f9664a066f..3a0a8ca57076 100644
--- a/drivers/input/touchscreen/usbtouchscreen.c
+++ b/drivers/input/touchscreen/usbtouchscreen.c
@@ -396,9 +396,12 @@ static int gunze_read_data(struct usbtouch_usb *dev, unsigned char *pkt)
 static int dmc_tsc10_init(struct usbtouch_usb *usbtouch)
 {
         struct usb_device *dev = usbtouch->udev;
-        int ret;
-        unsigned char buf[2];
+        int ret = -ENOMEM;
+        unsigned char *buf;
 
+        buf = kmalloc(2, GFP_KERNEL);
+        if (!buf)
+                goto err_nobuf;
         /* reset */
         buf[0] = buf[1] = 0xFF;
         ret = usb_control_msg(dev, usb_rcvctrlpipe (dev, 0),
@@ -406,9 +409,11 @@ static int dmc_tsc10_init(struct usbtouch_usb *usbtouch)
                               USB_DIR_IN | USB_TYPE_VENDOR | USB_RECIP_DEVICE,
                               0, 0, buf, 2, USB_CTRL_SET_TIMEOUT);
         if (ret < 0)
-                return ret;
-        if (buf[0] != 0x06 || buf[1] != 0x00)
-                return -ENODEV;
+                goto err_out;
+        if (buf[0] != 0x06 || buf[1] != 0x00) {
+                ret = -ENODEV;
+                goto err_out;
+        }
 
         /* set coordinate output rate */
         buf[0] = buf[1] = 0xFF;
@@ -417,20 +422,22 @@ static int dmc_tsc10_init(struct usbtouch_usb *usbtouch)
                               USB_DIR_IN | USB_TYPE_VENDOR | USB_RECIP_DEVICE,
                               TSC10_RATE_150, 0, buf, 2, USB_CTRL_SET_TIMEOUT);
         if (ret < 0)
-                return ret;
+                goto err_out;
         if ((buf[0] != 0x06 || buf[1] != 0x00) &&
-            (buf[0] != 0x15 || buf[1] != 0x01))
-                return -ENODEV;
+            (buf[0] != 0x15 || buf[1] != 0x01)) {
+                ret = -ENODEV;
+                goto err_out;
+        }
 
         /* start sending data */
         ret = usb_control_msg(dev, usb_rcvctrlpipe (dev, 0),
                               TSC10_CMD_DATA1,
                               USB_DIR_OUT | USB_TYPE_VENDOR | USB_RECIP_DEVICE,
                               0, 0, NULL, 0, USB_CTRL_SET_TIMEOUT);
-        if (ret < 0)
-                return ret;
-
-        return 0;
+err_out:
+        kfree(buf);
+err_nobuf:
+        return ret;
 }