[PATCH 5.4 012/155] macsec: restrict to ethernet devices

Greg Kroah-Hartman
2020-03-31T09:10:53Z

From: Willem de Bruijn <willemb@google.com>

[ Upstream commit b06d072ccc4b1acd0147b17914b7ad1caa1818bb ]

Only attach macsec to ethernet devices.

Syzbot was able to trigger a KMSAN warning in macsec_handle_frame
by attaching to a phonet device.

Macvlan has a similar check in macvlan_port_create.

v1->v2
- fix commit message typo

Reported-by: syzbot <syzkaller@googlegroups.com>
Signed-off-by: Willem de Bruijn <willemb@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---
drivers/net/macsec.c | 3 +++
1 file changed, 3 insertions(+)

--- a/drivers/net/macsec.c
+++ b/drivers/net/macsec.c
@@ -16,6 +16,7 @@
#include <net/genetlink.h>
#include <net/sock.h>
#include <net/gro_cells.h>
+#include <linux/if_arp.h>

#include <uapi/linux/if_macsec.h>

@@ -3236,6 +3237,8 @@ static int macsec_newlink(struct net *ne
real_dev = __dev_get_by_index(net, nla_get_u32(tb[IFLA_LINK]));
if (!real_dev)
return -ENODEV;
+ if (real_dev->type != ARPHRD_ETHER)
+ return -EINVAL;

dev->priv_flags |= IFF_MACSEC;