UBUNTU-CVE-2025-39977

In the Linux kernel, the following vulnerability has been resolved: futex: Prevent use-after-free during requeue-PI syzbot managed to trigger the following race: T1 T2 futexwaitrequeuepi futexdowait schedule futexrequeue futexproxytrylockatomic futexrequeuepiprepare requeuepiwakefutex...

CVE-2025-39977 futex: Prevent use-after-free during requeue-PI

In the Linux kernel, the following vulnerability has been resolved: futex: Prevent use-after-free during requeue-PI syzbot managed to trigger the following race: T1 T2 futexwaitrequeuepi futexdowait schedule futexrequeue futexproxytrylockatomic futexrequeuepiprepare requeuepiwakefutex...

CVE-2025-39977

In CVE-2025-39977, the Linux kernel futex subsystem (futex_wait_requeue_pi / futex_requeue_pi_complete path) suffers a use-after-free during requeue-PI race conditions. The race can leave futex_wait_requeue_pi() without synchronizing via futex_q::lock_ptr, risking a stale/garbage futex_q on retur...