act_ife: fix a potential use-after-free

[ Upstream commit 6d784f1625ea68783cc1fb17de8f6cd3e1660c3f ]

Immediately after module_put(), user could delete this
module, so e->ops could be already freed before we call
e->ops->release().

Fix this by moving module_put() after ops->release().

Fixes: ef6980b6becb ("introduce IFE action")
Cc: Jamal Hadi Salim <jhs@mojatatu.com>
Signed-off-by: Cong Wang <xiyou.wangcong@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This commit is contained in:
Cong Wang 2018-09-03 11:08:15 -07:00 committed by Greg Kroah-Hartman
parent bc71f393d3
commit 4fb15ff15b

View File

@ -395,7 +395,6 @@ static void _tcf_ife_cleanup(struct tc_action *a, int bind)
struct tcf_meta_info *e, *n;
list_for_each_entry_safe(e, n, &ife->metalist, metalist) {
module_put(e->ops->owner);
list_del(&e->metalist);
if (e->metaval) {
if (e->ops->release)
@ -403,6 +402,7 @@ static void _tcf_ife_cleanup(struct tc_action *a, int bind)
else
kfree(e->metaval);
}
module_put(e->ops->owner);
kfree(e);
}
}