Linux hwe edge: In the Linux kernel, the following vulnerability has been resolved: fuse: publish io-uring queues with release semantics fuse_uring_create_queue()… (CVE-2026-80858)

The Linux kernel's FUSE subsystem had a concurrency vulnerability in fuse_uring_create_queue() where the queue pointer was published using WRITE_ONCE() under a lock, but this did not guarantee the ordering of field initialization before the pointer assignment. Concurrent readers could fetch and dereference this pointer locklessly, potentially observing partially initialized data. The correct approach requires publishing the pointer with smp_store_release() to ensure proper memory ordering, and readers must use READ_ONCE() to avoid undefined behavior in concurrent reads. This flaw has been resolved in the Linux kernel.

The vulnerability could lead to undefined behavior when multiple threads concurrently access the io-uring queue pointers in the FUSE subsystem. This may cause data races or inconsistent reads of partially initialized data structures, potentially leading to kernel instability or crashes. There is no indication of direct privilege escalation or remote code execution from the provided data.

A fix has been implemented in the Linux kernel to address this issue by replacing WRITE_ONCE() with smp_store_release() when publishing the queue pointer and ensuring readers use READ_ONCE() for concurrent access. Users should apply the official kernel updates that include this fix once available. Patch status is not yet confirmed in the provided data; check the vendor advisory or Linux kernel mailing lists for current remediation guidance.