CVE-2026-80858

Summary

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

fuse: publish io-uring queues with release semantics

fuse_uring_create_queue() initializes a fuse_ring_queue and then publishes the pointer into ring->queues[qid] with WRITE_ONCE() under the fch->lock. There are several readers that may concurrently be fetching that pointer locklessly and then deferencing it.

WRITE_ONCE() doesn't ensure ordering of the queue's field initialization before the ring->queues[qid] pointer assignment. The queue must be published with smp_store_release() so the field initialization is guaranteed to happen before.

Readers in paths where the read may happen concurrently with the store need to use READ_ONCE() because any race involving a plain access is undefined.

Affected Software

VendorProductVersion RangeStatus
LinuxLinux24fe962c86f55347385933a1b06ca71b60854690 < a1bb359c443d048fe5dfd6ca9caf4e3897f3e9aaaffected
LinuxLinux24fe962c86f55347385933a1b06ca71b60854690 < 42df916e5a5f8fb4b60c8cefb54318d1ec02c580affected
LinuxLinux6.14affected
LinuxLinux0 < 6.14unaffected
LinuxLinux7.2.3 <= 7.2.*unaffected
LinuxLinux7.3-rc1 <= *unaffected

Weaknesses

References