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CVE-2026-74593 (GCVE-0-2026-74593)

Vulnerability from cvelistv5 – Published: 2026-08-22 15:31 – Updated: 2026-08-23 12:47
VLAI
Title
sched_ext: Take cgroup_lock() first in scx_cgroup_lock()
Summary
In the Linux kernel, the following vulnerability has been resolved: sched_ext: Take cgroup_lock() first in scx_cgroup_lock() scx_cgroup_lock() write-locks scx_cgroup_ops_rwsem and then takes cgroup_lock(), which can deadlock through kernfs: scx enable/disable cgroup rmdir cpu.weight write ------------------ ------------ ---------------- cgroup_lock() percpu_down_write(rwsem) cgroup_lock() kernfs_get_active() percpu_down_read(rwsem) kernfs_drain() The enable path waits for the rmdir to release cgroup_mutex. The rmdir, deactivating the cpu controller's files, waits in kernfs_drain() for the write's active reference. The write, in scx_group_set_weight(), waits for the rwsem behind the pending writer. Take cgroup_lock() first. The set_* paths take no cgroup locks inside the read side, so a pending write-lock then only waits for read sections that always run to completion, and no dependency from the rwsem back to cgroup_mutex remains.
Severity
No CVSS data available.
Assigner
References
Impacted products
Vendor Product Version CPE status
Linux Linux Affected: a5bd6ba30b3364354269b81ac55c2edca9a96d6d , < 2ca6b43edf83f8fc368cc3094ee5f3b1e8e0b0f0 (git)
Affected: a5bd6ba30b3364354269b81ac55c2edca9a96d6d , < a054c9ffa9b7a0dffb763837b91ac9d381ec6d10 (git)
Affected: a5bd6ba30b3364354269b81ac55c2edca9a96d6d , < 5f8b69642d18e1f3e11996707842ac530444e959 (git)
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Linux Linux Affected: 6.18
Unaffected: 0 , < 6.18 (semver)
Unaffected: 6.18.46 , ≤ 6.18.* (semver)
Unaffected: 7.1.9 , ≤ 7.1.* (semver)
Unaffected: 7.2 , ≤ * (original_commit_for_fix)
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{
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          "programFiles": [
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      "descriptions": [
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          "lang": "en",
          "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nsched_ext: Take cgroup_lock() first in scx_cgroup_lock()\n\nscx_cgroup_lock() write-locks scx_cgroup_ops_rwsem and then takes\ncgroup_lock(), which can deadlock through kernfs:\n\n  scx enable/disable         cgroup rmdir           cpu.weight write\n  ------------------         ------------           ----------------\n                             cgroup_lock()\n  percpu_down_write(rwsem)\n  cgroup_lock()\n                                                    kernfs_get_active()\n                                                    percpu_down_read(rwsem)\n                             kernfs_drain()\n\nThe enable path waits for the rmdir to release cgroup_mutex. The rmdir,\ndeactivating the cpu controller\u0027s files, waits in kernfs_drain() for the\nwrite\u0027s active reference. The write, in scx_group_set_weight(), waits for\nthe rwsem behind the pending writer.\n\nTake cgroup_lock() first. The set_* paths take no cgroup locks inside the\nread side, so a pending write-lock then only waits for read sections that\nalways run to completion, and no dependency from the rwsem back to\ncgroup_mutex remains."
        }
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        "orgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
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      "references": [
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          "url": "https://git.kernel.org/stable/c/5f8b69642d18e1f3e11996707842ac530444e959"
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    "cveId": "CVE-2026-74593",
    "datePublished": "2026-08-22T15:31:44.160Z",
    "dateReserved": "2026-08-15T05:44:03.919Z",
    "dateUpdated": "2026-08-23T12:47:36.437Z",
    "state": "PUBLISHED"
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      "cve": "CVE-2026-74593",
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}



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Forecast uses a logistic model when the trend is rising, or an exponential decay model when the trend is falling. Fitted via linearized least squares.

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Vulnerabilities whose description is nearest to this one in the vector space of the CIRCL/vulnerability-attack-technique-biencoder model. This is a similarity search over the bi-encoder space (plain cosine), not a classification, and it has no measured accuracy.