[PATCH 4.19 020/116] slcan: not call free_netdev before rtnl_unlock in slcan_open

From: Greg Kroah-Hartman
Date: Wed Apr 01 2020 - 12:23:42 EST


From: Oliver Hartkopp <socketcan@xxxxxxxxxxxx>

[ Upstream commit 2091a3d42b4f339eaeed11228e0cbe9d4f92f558 ]

As the description before netdev_run_todo, we cannot call free_netdev
before rtnl_unlock, fix it by reorder the code.

This patch is a 1:1 copy of upstream slip.c commit f596c87005f7
("slip: not call free_netdev before rtnl_unlock in slip_open").

Reported-by: yangerkun <yangerkun@xxxxxxxxxx>
Signed-off-by: Oliver Hartkopp <socketcan@xxxxxxxxxxxx>
Signed-off-by: David S. Miller <davem@xxxxxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
drivers/net/can/slcan.c | 3 +++
1 file changed, 3 insertions(+)

--- a/drivers/net/can/slcan.c
+++ b/drivers/net/can/slcan.c
@@ -621,7 +621,10 @@ err_free_chan:
tty->disc_data = NULL;
clear_bit(SLF_INUSE, &sl->flags);
slc_free_netdev(sl->dev);
+ /* do not call free_netdev before rtnl_unlock */
+ rtnl_unlock();
free_netdev(sl->dev);
+ return err;

err_exit:
rtnl_unlock();