Donate to e Foundation | Murena handsets with /e/OS | Own a part of Murena! Learn more

Commit a6bcfc89 authored by Li RongQing's avatar Li RongQing Committed by David S. Miller
Browse files

net: check extack._msg before print 



dev_set_mtu_ext is able to fail with a valid mtu value, at that
condition, extack._msg is not set and random since it is in stack,
then kernel will crash when print it.

Fixes: 7a4c53be ("net: report invalid mtu value via netlink extack")
Signed-off-by: default avatarZhang Yu <zhangyu31@baidu.com>
Signed-off-by: default avatarLi RongQing <lirongqing@baidu.com>
Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
parent 0ed4229b

net/core/dev.c

+2 −1
Original line number Diff line number Diff line
@@ -7583,8 +7583,9 @@ int dev_set_mtu(struct net_device *dev, int new_mtu) 
	struct netlink_ext_ack extack;

	int err;



	memset(&extack, 0, sizeof(extack));

	err = dev_set_mtu_ext(dev, new_mtu, &extack);

	if (err)

	if (err && extack._msg)

		net_err_ratelimited("%s: %s\n", dev->name, extack._msg);

	return err;

}