[PATCH 4.9 139/177] ppp: Destroy the mutex when cleanup

[Greg Kroah-Hartman]

4.9-stable review patch.  If anyone has any objections, please let me know.

------------------

From: Gao Feng <gfree.wind@xxxxxxxxxxx>


[ Upstream commit f02b2320b27c16b644691267ee3b5c110846f49e ]

The mutex_destroy only makes sense when enable DEBUG_MUTEX. For the
good readbility, it's better to invoke it in exit func when the init
func invokes mutex_init.

Signed-off-by: Gao Feng <gfree.wind@xxxxxxxxxxx>
Acked-by: Guillaume Nault <g.nault@xxxxxxxxxxxx>
Signed-off-by: David S. Miller <davem@xxxxxxxxxxxxx>
Signed-off-by: Sasha Levin <alexander.levin@xxxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
 drivers/net/ppp/ppp_generic.c |    1 +
 1 file changed, 1 insertion(+)

--- a/drivers/net/ppp/ppp_generic.c
+++ b/drivers/net/ppp/ppp_generic.c
@@ -958,6 +958,7 @@ static __net_exit void ppp_exit_net(stru
 	unregister_netdevice_many(&list);
 	rtnl_unlock();
 
+	mutex_destroy(&pn->all_ppp_mutex);
 	idr_destroy(&pn->units_idr);
 }