Just using 'rem > 0' might be unsafe, so it's better to use the nla_ok() instead. Because we can see from the nla_next() that '*remaining' might be smaller than 'totlen'. And nla_ok() will avoid it happening. For example, ovs_dp_process_packet() -> ovs_execute_actions() -> do_execute_actions(), and attr comes from OVS_CB(skb)->input_vport, which restores the received packet from the user space.
Fixes: ccb1352e76cff0524e7ccb2074826a092dd13016 ('net: Add Open vSwitch kernel components.') Signed-off-by: Jiasheng Jiang <jiash...@iscas.ac.cn> --- net/openvswitch/actions.c | 3 +-- 1 file changed, 1 insertion(+), 2 deletions(-) diff --git a/net/openvswitch/actions.c b/net/openvswitch/actions.c index 77d924a..c23537f 100644 --- a/net/openvswitch/actions.c +++ b/net/openvswitch/actions.c @@ -1238,8 +1238,7 @@ static int do_execute_actions(struct datapath *dp, struct sk_buff *skb, const struct nlattr *a; int rem; - for (a = attr, rem = len; rem > 0; - a = nla_next(a, &rem)) { + nla_for_each_attr(a, attr, len, rem) { int err = 0; switch (nla_type(a)) { -- 2.7.4 _______________________________________________ dev mailing list d...@openvswitch.org https://mail.openvswitch.org/mailman/listinfo/ovs-dev