This is a note to let you know that I've just added the patch titled usbip: vudc_tx: fix v_send_ret_submit() vulnerability to null xfer to my usb git tree which can be found at git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/usb.git in the usb-linus branch. The patch will show up in the next release of the linux-next tree (usually sometime within the next 24 hours during the week.) The patch will hopefully also be merged in Linus's tree for the next -rc kernel release. If you have any questions about this process, please let me know. >From 5fd77a3a0e408c23ab4002a57db980e46bc16e72 Mon Sep 17 00:00:00 2001 From: Shuah Khan <shuahkh@xxxxxxxxxxxxxxx> Date: Fri, 22 Dec 2017 19:23:47 -0700 Subject: 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@xxxxxxxxxxxxxxx> Cc: stable <stable@xxxxxxxxxxxxxxx> Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> --- drivers/usb/usbip/vudc_tx.c | 11 +++++++++-- 1 file changed, 9 insertions(+), 2 deletions(-) diff --git a/drivers/usb/usbip/vudc_tx.c b/drivers/usb/usbip/vudc_tx.c index 1440ae0919ec..3ccb17c3e840 100644 --- a/drivers/usb/usbip/vudc_tx.c +++ b/drivers/usb/usbip/vudc_tx.c @@ -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; -- 2.15.1