From 55cef78c244d0d076f5a75a35530ca63c92f4426 Mon Sep 17 00:00:00 2001 From: Lin Ma Date: Sun, 23 Jul 2023 16:02:05 +0800 Subject: [PATCH] macvlan: add forgotten nla_policy for IFLA_MACVLAN_BC_CUTOFF The previous commit 954d1fa1ac93 ("macvlan: Add netlink attribute for broadcast cutoff") added one additional attribute named IFLA_MACVLAN_BC_CUTOFF to allow broadcast cutfoff. However, it forgot to describe the nla_policy at macvlan_policy (drivers/net/macvlan.c). Hence, this suppose NLA_S32 (4 bytes) integer can be faked as empty (0 bytes) by a malicious user, which could leads to OOB in heap just like CVE-2023-3773. To fix it, this commit just completes the nla_policy description for IFLA_MACVLAN_BC_CUTOFF. This enforces the length check and avoids the potential OOB read. Fixes: 954d1fa1ac93 ("macvlan: Add netlink attribute for broadcast cutoff") Signed-off-by: Lin Ma Reviewed-by: Simon Horman Link: https://lore.kernel.org/r/20230723080205.3715164-1-linma@zju.edu.cn Signed-off-by: Jakub Kicinski --- drivers/net/macvlan.c | 1 + 1 file changed, 1 insertion(+) diff --git a/drivers/net/macvlan.c b/drivers/net/macvlan.c index 4a53debf..ed90816 100644 --- a/drivers/net/macvlan.c +++ b/drivers/net/macvlan.c @@ -1746,6 +1746,7 @@ static const struct nla_policy macvlan_policy[IFLA_MACVLAN_MAX + 1] = { [IFLA_MACVLAN_MACADDR_COUNT] = { .type = NLA_U32 }, [IFLA_MACVLAN_BC_QUEUE_LEN] = { .type = NLA_U32 }, [IFLA_MACVLAN_BC_QUEUE_LEN_USED] = { .type = NLA_REJECT }, + [IFLA_MACVLAN_BC_CUTOFF] = { .type = NLA_S32 }, }; int macvlan_link_register(struct rtnl_link_ops *ops) -- 2.7.4