[PATCH 4.4 37/45] rtl8150: Use heap buffers for all register access

Greg Kroah-Hartman
2017-04-19T14:58:49Z

From: Ben Hutchings <ben@decadent.org.uk>

commit 7926aff5c57b577ab0f43364ff0c59d968f6a414 upstream.

Allocating USB buffers on the stack is not portable, and no longer
works on x86_64 (with VMAP_STACK enabled as per default).

Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2")
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
Signed-off-by: David S. Miller <davem@davemloft.net>
Cc: Brad Spengler <spender@grsecurity.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

---
drivers/net/usb/rtl8150.c | 34 +++++++++++++++++++++++++++-------
1 file changed, 27 insertions(+), 7 deletions(-)

--- a/drivers/net/usb/rtl8150.c
+++ b/drivers/net/usb/rtl8150.c
@@ -155,16 +155,36 @@ static const char driver_name [] = "rtl8
*/
static int get_registers(rtl8150_t * dev, u16 indx, u16 size, void *data)
{
- return usb_control_msg(dev->udev, usb_rcvctrlpipe(dev->udev, 0),
- RTL8150_REQ_GET_REGS, RTL8150_REQT_READ,
- indx, 0, data, size, 500);
+ void *buf;
+ int ret;
+
+ buf = kmalloc(size, GFP_NOIO);
+ if (!buf)
+ return -ENOMEM;
+
+ ret = usb_control_msg(dev->udev, usb_rcvctrlpipe(dev->udev, 0),
+ RTL8150_REQ_GET_REGS, RTL8150_REQT_READ,
+ indx, 0, buf, size, 500);
+ if (ret > 0 && ret <= size)
+ memcpy(data, buf, ret);
+ kfree(buf);
+ return ret;
}

-static int set_registers(rtl8150_t * dev, u16 indx, u16 size, void *data)
+static int set_registers(rtl8150_t * dev, u16 indx, u16 size, const void *data)
{
- return usb_control_msg(dev->udev, usb_sndctrlpipe(dev->udev, 0),
- RTL8150_REQ_SET_REGS, RTL8150_REQT_WRITE,
- indx, 0, data, size, 500);
+ void *buf;
+ int ret;
+
+ buf = kmemdup(data, size, GFP_NOIO);
+ if (!buf)
+ return -ENOMEM;
+
+ ret = usb_control_msg(dev->udev, usb_sndctrlpipe(dev->udev, 0),
+ RTL8150_REQ_SET_REGS, RTL8150_REQT_WRITE,
+ indx, 0, buf, size, 500);
+ kfree(buf);
+ return ret;
}

static void async_set_reg_cb(struct urb *urb)