CVE-2026-80859

Published: September 8, 2026Last modified: September 8, 2026

Description

In the Linux kernel, the following vulnerability has been resolved: fuse: fix missing barrier when checking io-uring readiness fuse_block_alloc() reads fch->initialized and then fch->io_uring. fch->io_uring is set before fch->initialized, ordered by the smp_wmb() in fuse_chan_set_intialized(), but fuse_block_alloc() has no matching read barrier between the two loads. This may lead a CPU to observe fch->initialized=1 but fch->io_uring=0, and skip the check that blocks request allocation until the io-uring queues are ready. This can reintroduce the lock-order inversion deadlock that commit 3393ff964e0f prevents. Add an smp_rmb() barrier to pair with the smp_wmb() in fuse_chan_set_initialized() to prevent this.

Status

ProductReleasePackageStatus
Alpaquita Linux23 LTSlinux-ltsNot affected (6.1.33-r0)
25 LTSlinux-ltsNot affected (6.6.89-r0)
Streamlinux-ltsVulnerable (6.18.46-r0)

References

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