bond: Check length of IFLA_BOND_ARP_IP_TARGET attributes

Fixes: 7f28fa10 ("bonding: add arp_ip_target netlink support")
Reported-by: John Fastabend <john.fastabend@gmail.com>
Cc: Scott Feldman <sfeldma@cumulusnetworks.com>
Signed-off-by: Thomas Graf <tgraf@suug.ch>
Acked-by: John Fastabend <john.r.fastabend@intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

1 files changed, 6 insertions, 1 deletions

diff --git a/drivers/net/bonding/bond_netlink.c b/drivers/net/bonding/bond_netlink.c
index c13d83e15ace..45f09a66e6c9 100644
--- a/drivers/net/bonding/bond_netlink.c
+++ b/drivers/net/bonding/bond_netlink.c
@@ -225,7 +225,12 @@ static int bond_changelink(struct net_device *bond_dev,
 
                 bond_option_arp_ip_targets_clear(bond);
                 nla_for_each_nested(attr, data[IFLA_BOND_ARP_IP_TARGET], rem) {
-                        __be32 target = nla_get_be32(attr);
+                        __be32 target;
+
+                        if (nla_len(attr) < sizeof(target))
+                                return -EINVAL;
+
+                        target = nla_get_be32(attr);
 
                         bond_opt_initval(&newval, (__force u64)target);
                         err = __bond_opt_set(bond, BOND_OPT_ARP_TARGETS,