From: Johan Hovold <johan@kernel.org>
Date: Thu, 19 Sep 2019 10:30:39 +0200
Subject: USB: legousbtower: fix open after failed reset request
Git-commit: 0b074f6986751361ff442bc1127c1648567aa8d6
Patch-mainline: 5.4-rc3
References: bnc#1151927 5.3.7

The driver would return with a nonzero open count in case the reset
control request failed. This would prevent any further attempts to open
the char dev until the device was disconnected.

Fix this by incrementing the open count only on successful open.

Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2")
Signed-off-by: Johan Hovold <johan@kernel.org>
Cc: stable <stable@vger.kernel.org>
Link: https://lore.kernel.org/r/20190919083039.30898-5-johan@kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Jiri Slaby <jslaby@suse.cz>
---
 drivers/usb/misc/legousbtower.c |    4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

--- a/drivers/usb/misc/legousbtower.c
+++ b/drivers/usb/misc/legousbtower.c
@@ -348,7 +348,6 @@ static int tower_open (struct inode *ino
 		retval = -EBUSY;
 		goto unlock_exit;
 	}
-	dev->open_count = 1;
 
 	/* reset the tower */
 	result = usb_control_msg (dev->udev,
@@ -388,13 +387,14 @@ static int tower_open (struct inode *ino
 		dev_err(&dev->udev->dev,
 			"Couldn't submit interrupt_in_urb %d\n", retval);
 		dev->interrupt_in_running = 0;
-		dev->open_count = 0;
 		goto unlock_exit;
 	}
 
 	/* save device in the file's private structure */
 	file->private_data = dev;
 
+	dev->open_count = 1;
+
 unlock_exit:
 	mutex_unlock(&dev->lock);