[PATCH] staging: wlan-ng: properly check endpoint types

Rustam Kovhaev
2020-07-22T16:11:04Z

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

diff --git a/drivers/staging/wlan-ng/prism2usb.c b/drivers/staging/wlan-ng/prism2usb.c
index 4689b2170e4f..456603fd26c0 100644
--- a/drivers/staging/wlan-ng/prism2usb.c
+++ b/drivers/staging/wlan-ng/prism2usb.c
@@ -61,11 +61,25 @@ static int prism2sta_probe_usb(struct usb_interface *interface,
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) {
--
2.27.0