net: ieee802154: forbid monitor for del llsec seclevel

stable inclusion
from stable-5.10.30
commit f872fb3feadd2212b4272b840decbf6c55df1c6a
bugzilla: 51791

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

commit 9dde1309 upstream.

This patch forbids to del llsec seclevel for monitor interfaces which we
don't support yet. Otherwise we will access llsec mib which isn't
initialized for monitors.

Reported-by: syzbot+fbf4fc11a819824e027b@syzkaller.appspotmail.com
Signed-off-by: NAlexander Aring <aahringo@redhat.com>
Link: https://lore.kernel.org/r/20210405003054.256017-15-aahringo@redhat.comSigned-off-by: NStefan Schmidt <stefan@datenfreihafen.org>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: NChen Jun <chenjun102@huawei.com>
Acked-by: N  Weilong Chen <chenweilong@huawei.com>
Signed-off-by: NZheng Zengkai <zhengzengkai@huawei.com>

net/ieee802154/nl802154.c

@@ -2092,6 +2092,9 @@ static int nl802154_del_llsec_seclevel(struct sk_buff *skb,
 	struct wpan_dev *wpan_dev = dev->ieee802154_ptr;
 	struct ieee802154_llsec_seclevel sl;
 
+	if (wpan_dev->iftype == NL802154_IFTYPE_MONITOR)
+		return -EOPNOTSUPP;
+
 	if (!info->attrs[NL802154_ATTR_SEC_LEVEL] ||
 	    llsec_parse_seclevel(info->attrs[NL802154_ATTR_SEC_LEVEL],
 				 &sl) < 0)