From 63ce18cfe685115ff8d341bae4c9204a79043cf0 Mon Sep 17 00:00:00 2001
From: Mike Galbraith <efault@gmx.de>
Date: Wed, 21 Feb 2007 12:45:35 -0800
Subject: [PATCH] driver core: refcounting fix

Fix a reference counting bug exposed by commit
725522b5453dd680412f2b6463a988e4fd148757.  If driver.mod_name exists, we
take a reference in module_add_driver(), and never release it.  Undo that
reference in module_remove_driver().

Signed-off-by: Mike Galbraith <efault@gmx.de>
Cc: Kay Sievers <kay.sievers@vrfy.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
---
 kernel/module.c | 6 ++++++
 1 file changed, 6 insertions(+)

diff --git a/kernel/module.c b/kernel/module.c
index 8c25b1a04fa..1ecf0810638 100644
--- a/kernel/module.c
+++ b/kernel/module.c
@@ -2425,6 +2425,12 @@ void module_remove_driver(struct device_driver *drv)
 			kfree(driver_name);
 		}
 	}
+	/*
+	 * Undo the additional reference we added in module_add_driver()
+	 * via kset_find_obj()
+	 */
+	if (drv->mod_name)
+		kobject_put(&drv->kobj);
 }
 EXPORT_SYMBOL(module_remove_driver);
 #endif
-- 
2.20.1