GHSA-WW4G-J47R-8Q39
Vulnerability from github – Published: 2026-08-06 09:30 – Updated: 2026-08-06 09:30In the Linux kernel, the following vulnerability has been resolved:
fuse-uring: fix data races on ring->ready
On weakly-ordered architectures, the store to fiq->ops can be reordered past the store to ring->ready, allowing a CPU that sees ring->ready == true via fuse_uring_ready() to dispatch requests through a stale fiq->ops pointer. Upgrade the store to smp_store_release() and the load in fuse_uring_ready() to smp_load_acquire() so that the preceding WRITE_ONCE(fiq->ops, ...) is visible to any CPU that observes ring->ready == true.
Additionally, fuse_uring_do_register() publishes ring->ready with WRITE_ONCE() but the fast-path check reads it with a plain load. This is a marked-vs-unmarked access that KCSAN will flag. Wrap it in READ_ONCE() to mark it without adding unnecessary ordering.
Also wrap the fc->ring load in fuse_uring_ready() in READ_ONCE() to prevent the compiler from reloading it between the NULL check and the dereference.
{
"affected": [],
"aliases": [
"CVE-2026-64588"
],
"database_specific": {
"cwe_ids": [],
"github_reviewed": false,
"github_reviewed_at": null,
"nvd_published_at": "2026-08-06T08:16:34Z",
"severity": null
},
"details": "In the Linux kernel, the following vulnerability has been resolved:\n\nfuse-uring: fix data races on ring-\u003eready\n\nOn weakly-ordered architectures, the store to fiq-\u003eops can be\nreordered past the store to ring-\u003eready, allowing a CPU that sees\nring-\u003eready == true via fuse_uring_ready() to dispatch requests\nthrough a stale fiq-\u003eops pointer. Upgrade the store to\nsmp_store_release() and the load in fuse_uring_ready() to\nsmp_load_acquire() so that the preceding WRITE_ONCE(fiq-\u003eops, ...)\nis visible to any CPU that observes ring-\u003eready == true.\n\nAdditionally, fuse_uring_do_register() publishes ring-\u003eready with\nWRITE_ONCE() but the fast-path check reads it with a plain load.\nThis is a marked-vs-unmarked access that KCSAN will flag. Wrap it in\nREAD_ONCE() to mark it without adding unnecessary ordering.\n\nAlso wrap the fc-\u003ering load in fuse_uring_ready() in READ_ONCE() to\nprevent the compiler from reloading it between the NULL check and the\ndereference.",
"id": "GHSA-ww4g-j47r-8q39",
"modified": "2026-08-06T09:30:32Z",
"published": "2026-08-06T09:30:32Z",
"references": [
{
"type": "ADVISORY",
"url": "https://nvd.nist.gov/vuln/detail/CVE-2026-64588"
},
{
"type": "WEB",
"url": "https://git.kernel.org/stable/c/46725a0056c884cf58a6897f222892807327d82d"
},
{
"type": "WEB",
"url": "https://git.kernel.org/stable/c/b156bb9966972122b148acab8bdf415cdb8176a3"
},
{
"type": "WEB",
"url": "https://git.kernel.org/stable/c/d01a09b442cb786cd44ccc7c84d57e2856d6737c"
}
],
"schema_version": "1.4.0",
"severity": []
}
Sightings
| Author | Source | Type | Date | Other |
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Nomenclature
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