The .release function of driver_ktype is 'driver_release()'.
This function frees the container_of this kobject.

So, this memory must not be freed explicitly in the error handling path of
'bus_add_driver()'. Otherwise a double free will occur.

Signed-off-by: Christophe JAILLET <[email protected]>
---
I have left the 'drv->p = NULL' even if it looks useless to me. It does not
hurt. I have also left a comment to explain why we do not free 'drv->p'
explicitly before zeroing this pointer.
---
 drivers/base/bus.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/base/bus.c b/drivers/base/bus.c
index e162c9a789ba..22a64fd3309b 100644
--- a/drivers/base/bus.c
+++ b/drivers/base/bus.c
@@ -698,7 +698,7 @@ int bus_add_driver(struct device_driver *drv)
 
 out_unregister:
        kobject_put(&priv->kobj);
-       kfree(drv->p);
+       /* drv->p is freed in driver_release()  */
        drv->p = NULL;
 out_put_bus:
        bus_put(bus);
-- 
2.11.0

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