From b7a937e90c3631cf3662a518cf2e4bf07f72967c Mon Sep 17 00:00:00 2001 From: Endre Kollar Date: Tue, 27 Jul 2010 12:40:00 +0200 Subject: [PATCH 462/524] Staging: usbip: Filtering illegal flags from remote driver The usb_submit_urb function in debug mode monitors the bogus flags. The client driver errors should not be conveyed to the local USB device. Signed-off-by: Endre Kollar Signed-off-by: Greg Kroah-Hartman --- drivers/staging/usbip/stub_rx.c | 55 +++++++++++++++++++++++++++++++++++++++ 1 files changed, 55 insertions(+), 0 deletions(-) diff --git a/drivers/staging/usbip/stub_rx.c b/drivers/staging/usbip/stub_rx.c index c602260..3e9d463 100644 --- a/drivers/staging/usbip/stub_rx.c +++ b/drivers/staging/usbip/stub_rx.c @@ -424,6 +424,60 @@ static int get_pipe(struct stub_device *sdev, int epnum, int dir) return 0; } +static void masking_bogus_flags(struct urb *urb) +{ + int xfertype; + struct usb_device *dev; + struct usb_host_endpoint *ep; + int is_out; + unsigned int allowed; + + if (!urb || urb->hcpriv || !urb->complete) + return; + dev = urb->dev; + if ((!dev) || (dev->state < USB_STATE_UNAUTHENTICATED)) + return; + + ep = (usb_pipein(urb->pipe) ? dev->ep_in : dev->ep_out) + [usb_pipeendpoint(urb->pipe)]; + if (!ep) + return; + + xfertype = usb_endpoint_type(&ep->desc); + if (xfertype == USB_ENDPOINT_XFER_CONTROL) { + struct usb_ctrlrequest *setup = + (struct usb_ctrlrequest *) urb->setup_packet; + + if (!setup) + return; + is_out = !(setup->bRequestType & USB_DIR_IN) || + !setup->wLength; + } else { + is_out = usb_endpoint_dir_out(&ep->desc); + } + + /* enforce simple/standard policy */ + allowed = (URB_NO_TRANSFER_DMA_MAP | URB_NO_SETUP_DMA_MAP | + URB_NO_INTERRUPT | URB_DIR_MASK | URB_FREE_BUFFER); + switch (xfertype) { + case USB_ENDPOINT_XFER_BULK: + if (is_out) + allowed |= URB_ZERO_PACKET; + /* FALLTHROUGH */ + case USB_ENDPOINT_XFER_CONTROL: + allowed |= URB_NO_FSBR; /* only affects UHCI */ + /* FALLTHROUGH */ + default: /* all non-iso endpoints */ + if (!is_out) + allowed |= URB_SHORT_NOT_OK; + break; + case USB_ENDPOINT_XFER_ISOC: + allowed |= URB_ISO_ASAP; + break; + } + urb->transfer_flags &= allowed; +} + static void stub_recv_cmd_submit(struct stub_device *sdev, struct usbip_header *pdu) { @@ -490,6 +544,7 @@ static void stub_recv_cmd_submit(struct stub_device *sdev, /* no need to submit an intercepted request, but harmless? */ tweak_special_requests(priv->urb); + masking_bogus_flags(priv->urb); /* urb is now ready to submit */ ret = usb_submit_urb(priv->urb, GFP_KERNEL); -- 1.7.1