usb: hso: fix error handling code of hso_create_net_device

The current error handling code of hso_create_net_device is
hso_free_net_device, no matter which errors lead to. For example,
WARNING in hso_free_net_device [1].

Fix this by refactoring the error handling code of
hso_create_net_device by handling different errors by different code.

[1] https://syzkaller.appspot.com/bug?id=66eff8d49af1b28370ad342787413e35bbe76efe

Reported-by: syzbot+44d53c7255bb1aea22d2@syzkaller.appspotmail.com
Fixes: 487731b0ac1f ("hso: fix bailout in error case of probe")
Signed-off-by: Dongliang Mu <mudongliangabcd@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

diff --git a/drivers/net/usb/hso.c b/drivers/net/usb/hso.c
index 63006838bdccd5b9b7d9029032051058be3d4519..dec96e8ab56791341181f0168c51523fc1eb17e9 100644 (file)
--- a/drivers/net/usb/hso.c
+++ b/drivers/net/usb/hso.c
@@ -2495,7 +2495,7 @@ static struct hso_device *hso_create_net_device(struct usb_interface *interface,
                           hso_net_init);
        if (!net) {
                dev_err(&interface->dev, "Unable to create ethernet device\n");
-               goto exit;
+               goto err_hso_dev;
        }
 
        hso_net = netdev_priv(net);
@@ -2508,13 +2508,13 @@ static struct hso_device *hso_create_net_device(struct usb_interface *interface,
                                      USB_DIR_IN);
        if (!hso_net->in_endp) {
                dev_err(&interface->dev, "Can't find BULK IN endpoint\n");
-               goto exit;
+               goto err_net;
        }
        hso_net->out_endp = hso_get_ep(interface, USB_ENDPOINT_XFER_BULK,
                                       USB_DIR_OUT);
        if (!hso_net->out_endp) {
                dev_err(&interface->dev, "Can't find BULK OUT endpoint\n");
-               goto exit;
+               goto err_net;
        }
        SET_NETDEV_DEV(net, &interface->dev);
        SET_NETDEV_DEVTYPE(net, &hso_type);
@@ -2523,18 +2523,18 @@ static struct hso_device *hso_create_net_device(struct usb_interface *interface,
        for (i = 0; i < MUX_BULK_RX_BUF_COUNT; i++) {
                hso_net->mux_bulk_rx_urb_pool[i] = usb_alloc_urb(0, GFP_KERNEL);
                if (!hso_net->mux_bulk_rx_urb_pool[i])
-                       goto exit;
+                       goto err_mux_bulk_rx;
                hso_net->mux_bulk_rx_buf_pool[i] = kzalloc(MUX_BULK_RX_BUF_SIZE,
                                                           GFP_KERNEL);
                if (!hso_net->mux_bulk_rx_buf_pool[i])
-                       goto exit;
+                       goto err_mux_bulk_rx;
        }
        hso_net->mux_bulk_tx_urb = usb_alloc_urb(0, GFP_KERNEL);
        if (!hso_net->mux_bulk_tx_urb)
-               goto exit;
+               goto err_mux_bulk_rx;
        hso_net->mux_bulk_tx_buf = kzalloc(MUX_BULK_TX_BUF_SIZE, GFP_KERNEL);
        if (!hso_net->mux_bulk_tx_buf)
-               goto exit;
+               goto err_free_tx_urb;
 
        add_net_device(hso_dev);
 
@@ -2542,7 +2542,7 @@ static struct hso_device *hso_create_net_device(struct usb_interface *interface,
        result = register_netdev(net);
        if (result) {
                dev_err(&interface->dev, "Failed to register device\n");
-               goto exit;
+               goto err_free_tx_buf;
        }
 
        hso_log_port(hso_dev);
@@ -2550,8 +2550,21 @@ static struct hso_device *hso_create_net_device(struct usb_interface *interface,
        hso_create_rfkill(hso_dev, interface);
 
        return hso_dev;
-exit:
-       hso_free_net_device(hso_dev, true);
+
+err_free_tx_buf:
+       remove_net_device(hso_dev);
+       kfree(hso_net->mux_bulk_tx_buf);
+err_free_tx_urb:
+       usb_free_urb(hso_net->mux_bulk_tx_urb);
+err_mux_bulk_rx:
+       for (i = 0; i < MUX_BULK_RX_BUF_COUNT; i++) {
+               usb_free_urb(hso_net->mux_bulk_rx_urb_pool[i]);
+               kfree(hso_net->mux_bulk_rx_buf_pool[i]);
+       }
+err_net:
+       free_netdev(net);
+err_hso_dev:
+       kfree(hso_dev);
        return NULL;
 }