CVE-2026-98235: net/sched: act_api: release tail references on DELACTION failure

In the Linux kernel, the following vulnerability has been resolved:

net/sched: actapi: release tail references on DELACTION failure

A batched RTMDELACTION request takes a temporary reference on each action before attempting any deletion. tcfactiondelete() clears each processed slot and drops its temporary reference before attempting the deletion. If deletion fails, tcaactiongd() calls tcfactionputmany() to release the remaining references, but its tcfactforeachaction() iterator stops at the first NULL slot.

When a batch stops at an action bound to a filter, this leaks a reference on each subsequent action. A later delete of an unbound action can then return success without removing it from the IDR.

Walk the full array in tcfactionputmany() and skip NULL slots to release the references held on the unprocessed actions.