bond: Check length of IFLA_BOND_ARP_IP_TARGET attributes

commit f6c6fda4c9e17940b0a2ba206b0408babfdc930c upstream.

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>
Signed-off-by: Luis Henriques <luis.henriques@canonical.com>

diff --git a/drivers/net/bonding/bond_netlink.c b/drivers/net/bonding/bond_netlink.c
index 5ab3c1847e6760e2f3ef7d2ec35085c2d4bf655b..8626bc0cb2afd04e88df865b94f84126b53bfdff 100644 (file)
--- a/drivers/net/bonding/bond_netlink.c
+++ b/drivers/net/bonding/bond_netlink.c
@@ -197,7 +197,12 @@ 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,