In the Linux kernel, the following vulnerability has been resolved:
perf/aux: Fix AUX buffer serialization
Ole reported that event->mmap_mutex is strictly insufficient to
serialize the AUX buffer, add a per RB mutex to fully serialize it.
Note that in the lock order comment the perf_event::mmap_mutex order
was already wrong, that is, it nesting under mmap_lock is not new with
this patch.
git.kernel.org/stable/c/2ab9d830262c132ab5db2f571003d80850d56b2a
git.kernel.org/stable/c/52d13d224fdf1299c8b642807fa1ea14d693f5ff
git.kernel.org/stable/c/7882923f1cb88dc1a17f2bf0c81b1fc80d44db82
git.kernel.org/stable/c/9dc7ad2b67772cfb94ceb3b0c9c4023c2463215d
git.kernel.org/stable/c/b9b6882e243b653d379abbeaa64a500182aba370
git.kernel.org/stable/c/c4b69bee3f4ef76809288fe6827bc14d4ae788ef