This is a note to let you know that I've just added the patch titled usbip: fix vudc_rx: harden CMD_SUBMIT path to handle malicious input 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 b78d830f0049ef1966dc1e0ebd1ec2a594e2cf25 Mon Sep 17 00:00:00 2001 From: Shuah Khan <shuahkh@xxxxxxxxxxxxxxx> Date: Fri, 22 Dec 2017 19:23:46 -0700 Subject: usbip: fix vudc_rx: harden CMD_SUBMIT path to handle malicious input Harden CMD_SUBMIT path to handle malicious input that could trigger large memory allocations. Add checks to validate transfer_buffer_length and number_of_packets to protect against bad input requesting for unbounded memory allocations. Signed-off-by: Shuah Khan <shuahkh@xxxxxxxxxxxxxxx> Cc: stable <stable@xxxxxxxxxxxxxxx> Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> --- drivers/usb/usbip/vudc_rx.c | 19 +++++++++++++++++++ 1 file changed, 19 insertions(+) diff --git a/drivers/usb/usbip/vudc_rx.c b/drivers/usb/usbip/vudc_rx.c index df1e30989148..1e8a23d92cb4 100644 --- a/drivers/usb/usbip/vudc_rx.c +++ b/drivers/usb/usbip/vudc_rx.c @@ -120,6 +120,25 @@ static int v_recv_cmd_submit(struct vudc *udc, urb_p->new = 1; urb_p->seqnum = pdu->base.seqnum; + if (urb_p->ep->type == USB_ENDPOINT_XFER_ISOC) { + /* validate packet size and number of packets */ + unsigned int maxp, packets, bytes; + + maxp = usb_endpoint_maxp(urb_p->ep->desc); + maxp *= usb_endpoint_maxp_mult(urb_p->ep->desc); + bytes = pdu->u.cmd_submit.transfer_buffer_length; + packets = DIV_ROUND_UP(bytes, maxp); + + if (pdu->u.cmd_submit.number_of_packets < 0 || + pdu->u.cmd_submit.number_of_packets > packets) { + dev_err(&udc->gadget.dev, + "CMD_SUBMIT: isoc invalid num packets %d\n", + pdu->u.cmd_submit.number_of_packets); + ret = -EMSGSIZE; + goto free_urbp; + } + } + ret = alloc_urb_from_cmd(&urb_p->urb, pdu, urb_p->ep->type); if (ret) { usbip_event_add(&udc->ud, VUDC_EVENT_ERROR_MALLOC); -- 2.15.1