[PATCH AUTOSEL 4.19 01/21] net: ieee802154: fix null deref in parse dev addr

Sasha Levin
2021-06-07T16:21:22Z

From: Dan Robertson <dan@dlrobertson.com>

[ 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>
---
net/ieee802154/nl802154.c | 9 +++++----
1 file changed, 5 insertions(+), 4 deletions(-)

diff --git a/net/ieee802154/nl802154.c b/net/ieee802154/nl802154.c
index b1c55db73764..6d4c71a52b6b 100644
--- a/net/ieee802154/nl802154.c
+++ b/net/ieee802154/nl802154.c
@@ -1315,19 +1315,20 @@ ieee802154_llsec_parse_dev_addr(struct nlattr *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:
--
2.30.2