net: ieee802154: fix null deref in parse dev addr

[ Upstream commit 9fdd04918a452980631ecc499317881c1d120b70 ]

Fix a logic error that could result in a null deref if the user sets
the mode incorrectly for the given addr type.

Signed-off-by: Dan Robertson <dan@dlrobertson.com>
Acked-by: Alexander Aring <aahringo@redhat.com>
Link: https://lore.kernel.org/r/20210423040214.15438-2-dan@dlrobertson.com
Signed-off-by: Stefan Schmidt <stefan@datenfreihafen.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>

diff --git a/net/ieee802154/nl802154.c b/net/ieee802154/nl802154.c
index f0b47d4..b34e4f8 100644 (file)
--- a/net/ieee802154/nl802154.c
+++ b/net/ieee802154/nl802154.c
@@ -1298,19 +1298,20 @@ ieee802154_llsec_parse_dev_addr(struct nlattr *nla,
        if (!nla || nla_parse_nested_deprecated(attrs, NL802154_DEV_ADDR_ATTR_MAX, nla, nl802154_dev_addr_policy, NULL))
                return -EINVAL;
 
-       if (!attrs[NL802154_DEV_ADDR_ATTR_PAN_ID] ||
-           !attrs[NL802154_DEV_ADDR_ATTR_MODE] ||
-           !(attrs[NL802154_DEV_ADDR_ATTR_SHORT] ||
-             attrs[NL802154_DEV_ADDR_ATTR_EXTENDED]))
+       if (!attrs[NL802154_DEV_ADDR_ATTR_PAN_ID] || !attrs[NL802154_DEV_ADDR_ATTR_MODE])
                return -EINVAL;
 
        addr->pan_id = nla_get_le16(attrs[NL802154_DEV_ADDR_ATTR_PAN_ID]);
        addr->mode = nla_get_u32(attrs[NL802154_DEV_ADDR_ATTR_MODE]);
        switch (addr->mode) {
        case NL802154_DEV_ADDR_SHORT:
+               if (!attrs[NL802154_DEV_ADDR_ATTR_SHORT])
+                       return -EINVAL;
                addr->short_addr = nla_get_le16(attrs[NL802154_DEV_ADDR_ATTR_SHORT]);
                break;
        case NL802154_DEV_ADDR_EXTENDED:
+               if (!attrs[NL802154_DEV_ADDR_ATTR_EXTENDED])
+                       return -EINVAL;
                addr->extended_addr = nla_get_le64(attrs[NL802154_DEV_ADDR_ATTR_EXTENDED]);
                break;
        default: