CVE-2026-68138

The CVE-2026-68138 issue concerns a race in the Linux kernel networking scheduler (net/sched) where qdisc_rtab_list and a non-atomic refcnt are mutated without proper locking. The historical RTNL mutex was supposed to serialize rate-table lookups, inserts, and frees, but CLS_FLOWER/TCF_PROTO_OPS_...