CVE-2026-80859

Full vulnerability record from the local CVENow database.

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.

Severity

Not scored

CVSS score

Not available

Vulnerability status

Received

Source identifier

416baaa9-dc9f-4396-8d5f-8c081fb06d67

Published

2026-09-04 16:18:15.070000

Last modified

2026-10-19 09:17:21.583000

View original CVE JSON

{
  "id": "CVE-2026-80859",
  "sourceIdentifier": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
  "published": "2026-09-04T16:18:15.070",
  "lastModified": "2026-10-19T09:17:21.583",
  "vulnStatus": "Received",
  "cveTags": [],
  "descriptions": [
    {
      "lang": "en",
      "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nfuse: fix missing barrier when checking io-uring readiness\n\nfuse_block_alloc() reads fch->initialized and then fch->io_uring.\nfch->io_uring is set before fch->initialized, ordered by the smp_wmb()\nin fuse_chan_set_intialized(), but fuse_block_alloc() has no matching\nread barrier between the two loads.\n\nThis may lead a CPU to observe fch->initialized=1 but fch->io_uring=0,\nand skip the check that blocks request allocation until the io-uring\nqueues are ready. This can reintroduce the lock-order inversion deadlock\nthat commit 3393ff964e0f prevents.\n\nAdd an smp_rmb() barrier to pair with the smp_wmb() in\nfuse_chan_set_initialized() to prevent this."
    }
  ],
  "affected": [
    {
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
      "affectedData": [
        {
          "vendor": "Linux",
          "product": "Linux",
          "defaultStatus": "unaffected",
          "programFiles": [
            "fs/fuse/dev.c"
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "versions": [
            {
              "version": "3393ff964e0fa5def66570c54a4612bf9df06b76",
              "lessThan": "8974575898cd7a4c818088f102b2e7a0286d3302",
              "versionType": "git",
              "status": "affected"
            },
            {
              "version": "3393ff964e0fa5def66570c54a4612bf9df06b76",
              "lessThan": "dd9c835709f4bb3e4256eea7573e4e6e18f956de",
              "versionType": "git",
              "status": "affected"
            },
            {
              "version": "3393ff964e0fa5def66570c54a4612bf9df06b76",
              "lessThan": "edb310bc27f0ad83e7fd558a3caf1a94ca511654",
              "versionType": "git",
              "status": "affected"
            }
          ]
        },
        {
          "vendor": "Linux",
          "product": "Linux",
          "defaultStatus": "affected",
          "programFiles": [
            "fs/fuse/dev.c"
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "versions": [
            {
              "version": "6.14",
              "status": "affected"
            },
            {
              "version": "0",
              "lessThan": "6.14",
              "versionType": "semver",
              "status": "unaffected"
            },
            {
              "version": "6.18.51",
              "lessThanOrEqual": "6.18.*",
              "versionType": "semver",
              "status": "unaffected"
            },
            {
              "version": "7.2.3",
              "lessThanOrEqual": "7.2.*",
              "versionType": "semver",
              "status": "unaffected"
            },
            {
              "version": "7.3",
              "lessThanOrEqual": "*",
              "versionType": "original_commit_for_fix",
              "status": "unaffected"
            }
          ]
        }
      ]
    }
  ],
  "metrics": {},
  "references": [
    {
      "url": "https://git.kernel.org/stable/c/8974575898cd7a4c818088f102b2e7a0286d3302",
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
    },
    {
      "url": "https://git.kernel.org/stable/c/dd9c835709f4bb3e4256eea7573e4e6e18f956de",
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
    },
    {
      "url": "https://git.kernel.org/stable/c/edb310bc27f0ad83e7fd558a3caf1a94ca511654",
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
    }
  ]
}