[PATCH net] net: usb: kaweth: validate USB endpoints

[Greg Kroah-Hartman <gregkh@linuxfoundation.org>]

The kaweth driver should validate that the device it is probing has the
proper number and types of USB endpoints it is expecting before it binds
to it.  If a malicious device were to not have the same urbs the driver
will crash later on when it blindly accesses these endpoints.

Cc: stable <stable@kernel.org>
Assisted-by: gkh_clanker_2000
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---
 drivers/net/usb/kaweth.c | 13 +++++++++++++
 1 file changed, 13 insertions(+)

diff --git a/drivers/net/usb/kaweth.c b/drivers/net/usb/kaweth.c
index c9efb7df892e..a8c3ecf7d810 100644
--- a/drivers/net/usb/kaweth.c
+++ b/drivers/net/usb/kaweth.c
@@ -885,6 +885,13 @@ static int kaweth_probe(
 	const eth_addr_t bcast_addr = { 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF };
 	int result = 0;
 	int rv = -EIO;
+	static const u8 bulk_ep_addr[] = {
+		1 | USB_DIR_IN,
+		2 | USB_DIR_OUT,
+		0};
+	static const u8 int_ep_addr[] = {
+		3 | USB_DIR_IN,
+		0};
 
 	dev_dbg(dev,
 		"Kawasaki Device Probe (Device number:%d): 0x%4.4x:0x%4.4x:0x%4.4x\n",
@@ -898,6 +905,12 @@ static int kaweth_probe(
 		(int)udev->descriptor.bLength,
 		(int)udev->descriptor.bDescriptorType);
 
+	if (!usb_check_bulk_endpoints(intf, bulk_ep_addr) ||
+	    !usb_check_int_endpoints(intf, int_ep_addr)) {
+		dev_err(dev, "couldn't find required endpoints\n");
+		return -ENODEV;
+	}
+
 	netdev = alloc_etherdev(sizeof(*kaweth));
 	if (!netdev)
 		return -ENOMEM;
-- 
2.53.0