CVE-2026-89988

In the Linux kernel, the following vulnerability has been resolved:

kprobes: Protect kprobe_blacklist with RCU

__within_kprobe_blacklist() traverses kprobe_blacklist without holding

kprobe_mutex. When a module is unloaded, kprobe_remove_area_blacklist()

removes blacklist entries and immediately frees them with kfree().

A concurrent call to within_kprobe_blacklist() can therefore dereference

freed memory.

Furthermore, within_kprobe_blacklist() can be called in atomic or

non-preemptible contexts where the sleeping kprobe_mutex cannot be taken.

Protect kprobe_blacklist with RCU. Use guard(rcu)() and

list_for_each_entry_rcu() for traversal, list_add_tail_rcu() for

insertions, list_del_rcu() for deletions, and kfree_rcu() to reclaim

entries safely after a grace period.