CVE-2026-68398

CVE-2026-68398 is a Linux kernel UAF in PPPoL2TP: pppol2tp_recv() can dereference a freed internal PPP channel when a bound-but-unattached channel is closed, leading to potential local escalation. The fix defers freeing the channel to an RCU callback (call_rcu) to ensure a grace period for in-fli...