Re: [Patch net-next v2] net_sched: use idr to allocate bpf filter handles

On 09/26/2017 01:11 AM, Cong Wang wrote:

On Mon, Sep 25, 2017 at 2:16 PM, Daniel Borkmann [off-list ref] wrote:

quoted

On 09/25/2017 07:13 PM, Cong Wang wrote:

[...]

quoted

There's this condition in the code before above idr allocations,
I think also in other classifiers:

         if (oldprog) {
                 if (handle && oldprog->handle != handle) {
                         ret = -EINVAL;
                         goto errout;
                 }
         }

Sure. If we use handle to find oldprog, it should have the
same handle. cls_bpf_get() guarantees it. This check is
redundant.

Good point, we should just test for 'oldprog && oldprog->handle !=
handle' and bail out then, otherwise it's just irritating. I can
see to fix this up later. Seems fine to me then, thanks!