[PATCH v3] ar5523: check endpoints type and direction in probe()

[Mazin Al Haddad]

Fixes a bug reported by syzbot, where a warning occurs in usb_submit_urb()
due to the wrong endpoint type. There is no check for both the number
of endpoints and the type.

Fix it by adding a check for the number of endpoints and the
direction/type of the endpoints. If the endpoints do not match -ENODEV is
returned.

usb 1-1: BOGUS urb xfer, pipe 3 != type 1
WARNING: CPU: 1 PID: 71 at drivers/usb/core/urb.c:502 usb_submit_urb+0xed2/0x18a0 drivers/usb/core/urb.c:502
Modules linked in:
CPU: 1 PID: 71 Comm: kworker/1:2 Not tainted 5.19.0-rc7-syzkaller-00150-g32f02a211b0a #0
Hardware name: Google Compute Engine/Google Compute Engine, BIOS Google 06/29/2022
Workqueue: usb_hub_wq hub_event
Call Trace:
 <TASK>
 ar5523_cmd+0x420/0x790 drivers/net/wireless/ath/ar5523/ar5523.c:275
 ar5523_cmd_read drivers/net/wireless/ath/ar5523/ar5523.c:302 [inline]
 ar5523_host_available drivers/net/wireless/ath/ar5523/ar5523.c:1376 [inline]
 ar5523_probe+0xc66/0x1da0 drivers/net/wireless/ath/ar5523/ar5523.c:1655

Link: https://syzkaller.appspot.com/bug?extid=1bc2c2afd44f820a669f
Reported-and-tested-by: syzbot+1bc2c2afd44f820a669f@xxxxxxxxxxxxxxxxxxxxxxxxx
Signed-off-by: Mazin Al Haddad <mazinalhaddad05@xxxxxxxxx>
---
v2->v3 changes:
 - Make use of helper functions instead of checking for direction
	 and type manually. 

 drivers/net/wireless/ath/ar5523/ar5523.c | 38 ++++++++++++++++++++++++
 1 file changed, 38 insertions(+)

diff --git a/drivers/net/wireless/ath/ar5523/ar5523.c b/drivers/net/wireless/ath/ar5523/ar5523.c
index 6f937d2cc126..69979e8f99fd 100644
--- a/drivers/net/wireless/ath/ar5523/ar5523.c
+++ b/drivers/net/wireless/ath/ar5523/ar5523.c
@@ -1581,8 +1581,46 @@ static int ar5523_probe(struct usb_interface *intf,
 	struct usb_device *dev = interface_to_usbdev(intf);
 	struct ieee80211_hw *hw;
 	struct ar5523 *ar;
+	struct usb_host_interface *host = intf->cur_altsetting;
+	struct usb_endpoint_descriptor *cmd_tx, *cmd_rx, *data_tx, *data_rx;
 	int error = -ENOMEM;
 
+	if (host->desc.bNumEndpoints != 4) {
+		dev_err(&dev->dev, "Wrong number of endpoints\n");
+		return -ENODEV;
+	}
+
+	for (int i = 0; i < host->desc.bNumEndpoints; ++i) {
+		struct usb_endpoint_descriptor *ep = &host->endpoint[i].desc;
+
+		if (usb_endpoint_is_bulk_out(ep)) {
+			if (!cmd_tx) {
+				if (ep->bEndpointAddress == AR5523_CMD_TX_PIPE)
+					cmd_tx = ep;
+			}
+			if (!data_tx) {
+				if (ep->bEndpointAddress == AR5523_DATA_TX_PIPE)
+					data_tx = ep;
+				}
+		}
+
+		if (usb_endpoint_is_bulk_in(ep)) {
+			if (!cmd_rx) {
+				if (ep->bEndpointAddress == AR5523_CMD_RX_PIPE)
+					cmd_rx = ep;
+			}
+			if (!data_rx) {
+				if (ep->bEndpointAddress == AR5523_DATA_RX_PIPE)
+					data_rx = ep;
+			}
+		}
+	}
+
+	if (!cmd_tx || !data_tx || !cmd_rx || !data_rx) {
+		dev_warn("wrong number of endpoints\n");
+		return -ENODEV;
+	}
+
 	/*
 	 * Load firmware if the device requires it.  This will return
 	 * -ENXIO on success and we'll get called back afer the usb
-- 
2.37.2