CVE-2024-40995 net/sched: act_api: fix possible infinite loop in tcf_idr_check_alloc()

In the Linux kernel, the following vulnerability has been resolved: net/sched: actapi: fix possible infinite loop in tcfidrcheckalloc syzbot found hanging tasks waiting on rtnllock 1 A reproducer is available in the syzbot bug. When a request to add multiple actions with the same index is sent, t...