1 files changed, 53 insertions, 22 deletions

diff --git a/drivers/usb/usbip/stub_dev.c b/drivers/usb/usbip/stub_dev.c
index 8e629b6a6f3f..a5a6a114219a 100644
--- a/drivers/usb/usbip/stub_dev.c
+++ b/drivers/usb/usbip/stub_dev.c
@@ -315,9 +315,17 @@ static int stub_probe(struct usb_device *udev)
 	const char *udev_busid = dev_name(&udev->dev);
 	struct bus_id_priv *busid_priv;
 	int rc = 0;
+	char save_status;
 
 	dev_dbg(&udev->dev, "Enter probe\n");
 
+	/* Not sure if this is our device. Allocate here to avoid
+	 * calling alloc while holding busid_table lock.
+	 */
+	sdev = stub_device_alloc(udev);
+	if (!sdev)
+		return -ENOMEM;
+
 	/* check we should claim or not by busid_table */
 	busid_priv = get_busid_priv(udev_busid);
 	if (!busid_priv || (busid_priv->status == STUB_BUSID_REMOV) ||
@@ -332,6 +340,9 @@ static int stub_probe(struct usb_device *udev)
 		 * See driver_probe_device() in driver/base/dd.c
 		 */
 		rc = -ENODEV;
+		if (!busid_priv)
+			goto sdev_free;
+
 		goto call_put_busid_priv;
 	}
 
@@ -351,12 +362,6 @@ static int stub_probe(struct usb_device *udev)
 		goto call_put_busid_priv;
 	}
 
-	/* ok, this is my device */
-	sdev = stub_device_alloc(udev);
-	if (!sdev) {
-		rc = -ENOMEM;
-		goto call_put_busid_priv;
-	}
 
 	dev_info(&udev->dev,
 		"usbip-host: register new device (bus %u dev %u)\n",
@@ -366,9 +371,16 @@ static int stub_probe(struct usb_device *udev)
 
 	/* set private data to usb_device */
 	dev_set_drvdata(&udev->dev, sdev);
+
 	busid_priv->sdev = sdev;
 	busid_priv->udev = udev;
 
+	save_status = busid_priv->status;
+	busid_priv->status = STUB_BUSID_ALLOC;
+
+	/* release the busid_lock */
+	put_busid_priv(busid_priv);
+
 	/*
 	 * Claim this hub port.
 	 * It doesn't matter what value we pass as owner
@@ -386,10 +398,8 @@ static int stub_probe(struct usb_device *udev)
 		dev_err(&udev->dev, "stub_add_files for %s\n", udev_busid);
 		goto err_files;
 	}
-	busid_priv->status = STUB_BUSID_ALLOC;
 
-	rc = 0;
-	goto call_put_busid_priv;
+	return 0;
 
 err_files:
 	usb_hub_release_port(udev->parent, udev->portnum,
@@ -398,23 +408,30 @@ err_port:
 	dev_set_drvdata(&udev->dev, NULL);
 	usb_put_dev(udev);
 
+	/* we already have busid_priv, just lock busid_lock */
+	spin_lock(&busid_priv->busid_lock);
 	busid_priv->sdev = NULL;
-	stub_device_free(sdev);
+	busid_priv->status = save_status;
+	spin_unlock(&busid_priv->busid_lock);
+	/* lock is released - go to free */
+	goto sdev_free;
 
 call_put_busid_priv:
+	/* release the busid_lock */
 	put_busid_priv(busid_priv);
+
+sdev_free:
+	stub_device_free(sdev);
+
 	return rc;
 }
 
 static void shutdown_busid(struct bus_id_priv *busid_priv)
 {
-	if (busid_priv->sdev && !busid_priv->shutdown_busid) {
-		busid_priv->shutdown_busid = 1;
-		usbip_event_add(&busid_priv->sdev->ud, SDEV_EVENT_REMOVED);
+	usbip_event_add(&busid_priv->sdev->ud, SDEV_EVENT_REMOVED);
 
-		/* wait for the stop of the event handler */
-		usbip_stop_eh(&busid_priv->sdev->ud);
-	}
+	/* wait for the stop of the event handler */
+	usbip_stop_eh(&busid_priv->sdev->ud);
 }
 
 /*
@@ -441,11 +458,16 @@ static void stub_disconnect(struct usb_device *udev)
 	/* get stub_device */
 	if (!sdev) {
 		dev_err(&udev->dev, "could not get device");
-		goto call_put_busid_priv;
+		/* release busid_lock */
+		put_busid_priv(busid_priv);
+		return;
 	}
 
 	dev_set_drvdata(&udev->dev, NULL);
 
+	/* release busid_lock before call to remove device files */
+	put_busid_priv(busid_priv);
+
 	/*
 	 * NOTE: rx/tx threads are invoked for each usb_device.
 	 */
@@ -456,27 +478,36 @@ static void stub_disconnect(struct usb_device *udev)
 				  (struct usb_dev_state *) udev);
 	if (rc) {
 		dev_dbg(&udev->dev, "unable to release port\n");
-		goto call_put_busid_priv;
+		return;
 	}
 
 	/* If usb reset is called from event handler */
 	if (usbip_in_eh(current))
-		goto call_put_busid_priv;
+		return;
+
+	/* we already have busid_priv, just lock busid_lock */
+	spin_lock(&busid_priv->busid_lock);
+	if (!busid_priv->shutdown_busid)
+		busid_priv->shutdown_busid = 1;
+	/* release busid_lock */
+	spin_unlock(&busid_priv->busid_lock);
 
 	/* shutdown the current connection */
 	shutdown_busid(busid_priv);
 
 	usb_put_dev(sdev->udev);
 
+	/* we already have busid_priv, just lock busid_lock */
+	spin_lock(&busid_priv->busid_lock);
 	/* free sdev */
 	busid_priv->sdev = NULL;
 	stub_device_free(sdev);
 
 	if (busid_priv->status == STUB_BUSID_ALLOC)
 		busid_priv->status = STUB_BUSID_ADDED;
-
-call_put_busid_priv:
-	put_busid_priv(busid_priv);
+	/* release busid_lock */
+	spin_unlock(&busid_priv->busid_lock);
+	return;
 }
 
 #ifdef CONFIG_PM