CVE Catalog

CVE-2026-90247

Unknown
Published: Translated: NVD NIST

Summary

In the Linux kernel's BPF subsystem, there is a mmap_lock leak in the irq_work path. A nested caller can reuse the slot before the first caller queues it, leading to double locking of mmap_lock and a lock leak, blocking exit_mmap().

Risk Assessment

Lock leak can lead to deadlocks and blocking of processes, potentially used for DoS attacks.

Recommendation

Apply the Linux kernel update containing the fix that reserves the slot before mmap_read_trylock() and releases it after unlock.

Other vulnerabilities in Linux kernel

See all
Original NVD description (English source)

In the Linux kernel, the following vulnerability has been resolved: bpf: Fix mmap_lock leak in irq_work path stack_map_get_build_id_offset() introduced a per-CPU irq_work to defer mmap_read_unlock() from NMI context, and bpf_find_vma() later reused the same mmap_unlock_work. Both callers only check whether the work is busy before taking mmap_lock, so a nested caller can reuse the slot before the first caller queues it. Two read locks may then be acquired while only one deferred unlock runs, leaking a read lock and blocking exit_mmap(). Reserve the per-CPU slot before mmap_read_trylock(). Use the same wrapper in stackmap and bpf_find_vma() so both callers release the reservation on trylock failure. Keep rejecting the slot while the irq_work remains busy. Release it after the irq_work callback unlocks the mm.

Vulnerability data from NVD (NIST) · CISA KEV · EPSS