Pan Bian d4327131db exportfs: do not read dentry after free
[ Upstream commit 2084ac6c505a58f7efdec13eba633c6aaa085ca5 ]

The function dentry_connected calls dput(dentry) to drop the previously
acquired reference to dentry. In this case, dentry can be released.
After that, IS_ROOT(dentry) checks the condition
(dentry == dentry->d_parent), which may result in a use-after-free bug.
This patch directly compares dentry with its parent obtained before
dropping the reference.

Fixes: a056cc8934c("exportfs: stop retrying once we race with
rename/remove")

Signed-off-by: Pan Bian <bianpan2016@163.com>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2018-12-17 21:55:10 +01:00
..
2017-12-20 10:04:56 +01:00
2017-08-06 19:19:42 -07:00
2018-12-13 09:21:27 +01:00
2018-11-21 09:27:44 +01:00
2017-11-30 08:37:20 +00:00
2018-11-21 09:27:35 +01:00
2018-09-15 09:40:41 +02:00
2018-07-03 11:21:34 +02:00
2018-06-06 16:46:23 +02:00
2015-11-10 12:07:22 -08:00
2017-06-14 13:16:24 +02:00
2015-11-16 23:54:45 -08:00
2018-05-16 10:06:51 +02:00
2015-11-16 23:54:45 -08:00
2017-06-14 13:16:24 +02:00
2018-02-16 20:09:43 +01:00
2017-06-14 13:16:24 +02:00
2018-09-09 20:04:36 +02:00