I've observed a NULL pointer dereference in ieee802154_del_iface() during
netlink fuzzing. It's the ->wpan_phy dereference here:
phy = dev->ieee802154_ptr->wpan_phy;
My bet is that we're not checking that this is an IEEE802154 interface,
so let's do what ieee802154_nl_get_dev() is doing. (Maybe we should even
be calling this directly?)
Cc: Lennert Buytenhek <buyt...@wantstofly.org>
Cc: Alexander Aring <alex.ar...@gmail.com>
Cc: Marcel Holtmann <mar...@holtmann.org>
Cc: Dmitry Eremin-Solenikov <dbarysh...@gmail.com>
Cc: Sergey Lapin <sla...@ossfans.org>
Signed-off-by: Vegard Nossum <vegard.nos...@oracle.com>
---
net/ieee802154/nl-phy.c | 6 +++++-
1 file changed, 5 insertions(+), 1 deletion(-)
diff --git a/net/ieee802154/nl-phy.c b/net/ieee802154/nl-phy.c
index 77d7301..dc2960b 100644
--- a/net/ieee802154/nl-phy.c
+++ b/net/ieee802154/nl-phy.c
@@ -286,9 +286,12 @@ int ieee802154_del_iface(struct sk_buff *skb, struct
genl_info *info)
if (name[nla_len(info->attrs[IEEE802154_ATTR_DEV_NAME]) - 1] != '\0')
return -EINVAL; /* name should be null-terminated */
+ rc = -ENODEV;
dev = dev_get_by_name(genl_info_net(info), name);
if (!dev)
- return -ENODEV;
+ return rc;
+ if (dev->type != ARPHRD_IEEE802154)
+ goto out;
phy = dev->ieee802154_ptr->wpan_phy;
BUG_ON(!phy);
@@ -342,6 +345,7 @@ nla_put_failure:
nlmsg_free(msg);
out_dev:
wpan_phy_put(phy);
+out:
if (dev)
dev_put(dev);
--
1.9.1
