[PATCH v3] usb: usbip: fix a refcount leak in stub_probe()

From: Hangyu Hua <hbh25y@gmail.com>
To: valentina.manea.m@gmail.com, shuah@kernel.org,
	gregkh@linuxfoundation.org, khoroshilov@ispras.ru,
	skhan@linuxfoundation.org
Cc: linux-usb@vger.kernel.org, linux-kernel@vger.kernel.org,
	Hangyu Hua <hbh25y@gmail.com>
Subject: [PATCH v3] usb: usbip: fix a refcount leak in stub_probe()
Date: Tue, 12 Apr 2022 10:02:57 +0800	[thread overview]
Message-ID: <20220412020257.9767-1-hbh25y@gmail.com> (raw)

usb_get_dev() is called in stub_device_alloc(). When stub_probe() fails
after that, usb_put_dev() needs to be called to release the reference.

Fix this by moving usb_put_dev() to sdev_free error path handling.

Find this by code review.

Fixes: 3ff67445750a ("usbip: fix error handling in stub_probe()")
Signed-off-by: Hangyu Hua <hbh25y@gmail.com>
Reviewed-by: Shuah Khan <skhan@linuxfoundation.org>
---

v2: add more description of this patch.

v3: add how to find the problem.

 drivers/usb/usbip/stub_dev.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/usb/usbip/stub_dev.c b/drivers/usb/usbip/stub_dev.c
index d8d3892e5a69..3c6d452e3bf4 100644
--- a/drivers/usb/usbip/stub_dev.c
+++ b/drivers/usb/usbip/stub_dev.c
@@ -393,7 +393,6 @@ static int stub_probe(struct usb_device *udev)
 
 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);
@@ -408,6 +407,7 @@ static int stub_probe(struct usb_device *udev)
 	put_busid_priv(busid_priv);
 
 sdev_free:
+	usb_put_dev(udev);
 	stub_device_free(sdev);
 
 	return rc;
-- 
2.25.1

