net: sched: fix flush on non-existing chain

User was able to perform filter flush on chain 0 even if it didn't have
any filters in it. With the patch that avoided implicit chain 0
creation, this changed. So in case user wants filter flush on chain
which does not exist, just return success. There's no reason for non-0
chains to behave differently than chain 0, so do the same for them.

Reported-by: Ido Schimmel <idosch@mellanox.com>
Fixes: f71e0ca4db ("net: sched: Avoid implicit chain 0 creation")
Signed-off-by: Jiri Pirko <jiri@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
This commit is contained in:
Jiri Pirko 2018-08-03 11:08:47 +02:00 committed by David S. Miller
parent 6fd544c897
commit 5ca8a25c14

View File

@ -1389,6 +1389,13 @@ static int tc_del_tfilter(struct sk_buff *skb, struct nlmsghdr *n,
}
chain = tcf_chain_get(block, chain_index, false);
if (!chain) {
/* User requested flush on non-existent chain. Nothing to do,
* so just return success.
*/
if (prio == 0) {
err = 0;
goto errout;
}
NL_SET_ERR_MSG(extack, "Cannot find specified filter chain");
err = -EINVAL;
goto errout;