usbip: vudc_tx: fix v_send_ret_submit() vulnerability to null xfer buffer

v_send_ret_submit() handles urb with a null transfer_buffer, when it
replays a packet with potential malicious data that could contain a
null buffer.

Add a check for the condition when actual_length > 0 and transfer_buffer
is null.

Signed-off-by: Shuah Khan <shuahkh@osg.samsung.com>
Cc: stable <stable@vger.kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This commit is contained in:
Shuah Khan 2017-12-22 19:23:47 -07:00 committed by Greg Kroah-Hartman
parent e1346fd87c
commit 5fd77a3a0e

View File

@ -85,6 +85,13 @@ static int v_send_ret_submit(struct vudc *udc, struct urbp *urb_p)
memset(&pdu_header, 0, sizeof(pdu_header));
memset(&msg, 0, sizeof(msg));
if (urb->actual_length > 0 && !urb->transfer_buffer) {
dev_err(&udc->gadget.dev,
"urb: actual_length %d transfer_buffer null\n",
urb->actual_length);
return -1;
}
if (urb_p->type == USB_ENDPOINT_XFER_ISOC)
iovnum = 2 + urb->number_of_packets;
else
@ -100,8 +107,8 @@ static int v_send_ret_submit(struct vudc *udc, struct urbp *urb_p)
/* 1. setup usbip_header */
setup_ret_submit_pdu(&pdu_header, urb_p);
usbip_dbg_stub_tx("setup txdata seqnum: %d urb: %p\n",
pdu_header.base.seqnum, urb);
usbip_dbg_stub_tx("setup txdata seqnum: %d\n",
pdu_header.base.seqnum);
usbip_header_correct_endian(&pdu_header, 1);
iov[iovnum].iov_base = &pdu_header;