can: mcba_usb: properly check endpoint type

Syzbot reported warning in usb_submit_urb() which is caused by wrong
endpoint type. We should check that in endpoint is actually present to
prevent this warning.

Found pipes are now saved to struct mcba_priv and code uses them
directly instead of making pipes in place.

Fail log:

| usb 5-1: BOGUS urb xfer, pipe 3 != type 1
| WARNING: CPU: 1 PID: 49 at drivers/usb/core/urb.c:502 usb_submit_urb+0xed2/0x18a0 drivers/usb/core/urb.c:502
| Modules linked in:
| CPU: 1 PID: 49 Comm: kworker/1:2 Not tainted 5.17.0-rc6-syzkaller-00184-g38f80f42147f #0
| Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.14.0-2 04/01/2014
| Workqueue: usb_hub_wq hub_event
| RIP: 0010:usb_submit_urb+0xed2/0x18a0 drivers/usb/core/urb.c:502
| ...
| Call Trace:
|  <TASK>
|  mcba_usb_start drivers/net/can/usb/mcba_usb.c:662 [inline]
|  mcba_usb_probe+0x8a3/0xc50 drivers/net/can/usb/mcba_usb.c:858
|  usb_probe_interface+0x315/0x7f0 drivers/usb/core/driver.c:396
|  call_driver_probe drivers/base/dd.c:517 [inline]

Fixes: 51f3baad7de9 ("can: mcba_usb: Add support for Microchip CAN BUS Analyzer")
Link: https://lore.kernel.org/all/20220313100903.10868-1-paskripkin@gmail.com
Reported-and-tested-by: syzbot+3bc1dce0cc0052d60fde@syzkaller.appspotmail.com
Signed-off-by: Pavel Skripkin <paskripkin@gmail.com>
Reviewed-by: Vincent Mailhol <mailhol.vincent@wanadoo.fr>
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>

diff --git a/drivers/net/can/usb/mcba_usb.c b/drivers/net/can/usb/mcba_usb.c
index 7c198eb5bc9c327d640cadf3b9709dc2aba5e444..c45a814e1de2f9106b0c464301bfb0c53ae739ae 100644 (file)
--- a/drivers/net/can/usb/mcba_usb.c
+++ b/drivers/net/can/usb/mcba_usb.c
@@ -33,10 +33,6 @@
 #define MCBA_USB_RX_BUFF_SIZE 64
 #define MCBA_USB_TX_BUFF_SIZE (sizeof(struct mcba_usb_msg))
 
-/* MCBA endpoint numbers */
-#define MCBA_USB_EP_IN 1
-#define MCBA_USB_EP_OUT 1
-
 /* Microchip command id */
 #define MBCA_CMD_RECEIVE_MESSAGE 0xE3
 #define MBCA_CMD_I_AM_ALIVE_FROM_CAN 0xF5
@@ -83,6 +79,8 @@ struct mcba_priv {
        atomic_t free_ctx_cnt;
        void *rxbuf[MCBA_MAX_RX_URBS];
        dma_addr_t rxbuf_dma[MCBA_MAX_RX_URBS];
+       int rx_pipe;
+       int tx_pipe;
 };
 
 /* CAN frame */
@@ -268,10 +266,8 @@ static netdev_tx_t mcba_usb_xmit(struct mcba_priv *priv,
 
        memcpy(buf, usb_msg, MCBA_USB_TX_BUFF_SIZE);
 
-       usb_fill_bulk_urb(urb, priv->udev,
-                         usb_sndbulkpipe(priv->udev, MCBA_USB_EP_OUT), buf,
-                         MCBA_USB_TX_BUFF_SIZE, mcba_usb_write_bulk_callback,
-                         ctx);
+       usb_fill_bulk_urb(urb, priv->udev, priv->tx_pipe, buf, MCBA_USB_TX_BUFF_SIZE,
+                         mcba_usb_write_bulk_callback, ctx);
 
        urb->transfer_flags |= URB_NO_TRANSFER_DMA_MAP;
        usb_anchor_urb(urb, &priv->tx_submitted);
@@ -607,7 +603,7 @@ static void mcba_usb_read_bulk_callback(struct urb *urb)
 resubmit_urb:
 
        usb_fill_bulk_urb(urb, priv->udev,
-                         usb_rcvbulkpipe(priv->udev, MCBA_USB_EP_OUT),
+                         priv->rx_pipe,
                          urb->transfer_buffer, MCBA_USB_RX_BUFF_SIZE,
                          mcba_usb_read_bulk_callback, priv);
 
@@ -652,7 +648,7 @@ static int mcba_usb_start(struct mcba_priv *priv)
                urb->transfer_dma = buf_dma;
 
                usb_fill_bulk_urb(urb, priv->udev,
-                                 usb_rcvbulkpipe(priv->udev, MCBA_USB_EP_IN),
+                                 priv->rx_pipe,
                                  buf, MCBA_USB_RX_BUFF_SIZE,
                                  mcba_usb_read_bulk_callback, priv);
                urb->transfer_flags |= URB_NO_TRANSFER_DMA_MAP;
@@ -806,6 +802,13 @@ static int mcba_usb_probe(struct usb_interface *intf,
        struct mcba_priv *priv;
        int err;
        struct usb_device *usbdev = interface_to_usbdev(intf);
+       struct usb_endpoint_descriptor *in, *out;
+
+       err = usb_find_common_endpoints(intf->cur_altsetting, &in, &out, NULL, NULL);
+       if (err) {
+               dev_err(&intf->dev, "Can't find endpoints\n");
+               return err;
+       }
 
        netdev = alloc_candev(sizeof(struct mcba_priv), MCBA_MAX_TX_URBS);
        if (!netdev) {
@@ -851,6 +854,9 @@ static int mcba_usb_probe(struct usb_interface *intf,
                goto cleanup_free_candev;
        }
 
+       priv->rx_pipe = usb_rcvbulkpipe(priv->udev, in->bEndpointAddress);
+       priv->tx_pipe = usb_sndbulkpipe(priv->udev, out->bEndpointAddress);
+
        devm_can_led_init(netdev);
 
        /* Start USB dev only if we have successfully registered CAN device */