[PATCH 4.19 65/86] staging: wlan-ng: properly check endpoint types

Greg Kroah-Hartman
2020-07-27T14:37:34Z

From: Rustam Kovhaev <rkovhaev@gmail.com>

commit faaff9765664009c1c7c65551d32e9ed3b1dda8f upstream.

As syzkaller detected, wlan-ng driver does not do sanity check of
endpoints in prism2sta_probe_usb(), add check for xfer direction and type

Reported-and-tested-by: syzbot+c2a1fa67c02faa0de723@syzkaller.appspotmail.com
Link: https://syzkaller.appspot.com/bug?extid=c2a1fa67c02faa0de723
Signed-off-by: Rustam Kovhaev <rkovhaev@gmail.com>
Cc: stable <stable@vger.kernel.org>
Link: https://lore.kernel.org/r/20200722161052.999754-1-rkovhaev@gmail.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

---
drivers/staging/wlan-ng/prism2usb.c | 16 +++++++++++++++-
1 file changed, 15 insertions(+), 1 deletion(-)

--- a/drivers/staging/wlan-ng/prism2usb.c
+++ b/drivers/staging/wlan-ng/prism2usb.c
@@ -61,11 +61,25 @@ static int prism2sta_probe_usb(struct us
const struct usb_device_id *id)
{
struct usb_device *dev;
-
+ const struct usb_endpoint_descriptor *epd;
+ const struct usb_host_interface *iface_desc = interface->cur_altsetting;
struct wlandevice *wlandev = NULL;
struct hfa384x *hw = NULL;
int result = 0;

+ if (iface_desc->desc.bNumEndpoints != 2) {
+ result = -ENODEV;
+ goto failed;
+ }
+
+ result = -EINVAL;
+ epd = &iface_desc->endpoint[1].desc;
+ if (!usb_endpoint_is_bulk_in(epd))
+ goto failed;
+ epd = &iface_desc->endpoint[2].desc;
+ if (!usb_endpoint_is_bulk_out(epd))
+ goto failed;
+
dev = interface_to_usbdev(interface);
wlandev = create_wlan();
if (!wlandev) {