FKIE_CVE-2025-38620
Vulnerability from fkie_nvd - Published: 2025-08-22 16:15 - Updated: 2026-06-17 09:17
Severity
Summary
In the Linux kernel, the following vulnerability has been resolved:
zloop: fix KASAN use-after-free of tag set
When a zoned loop device, or zloop device, is removed, KASAN enabled
kernel reports "BUG KASAN use-after-free" in blk_mq_free_tag_set(). The
BUG happens because zloop_ctl_remove() calls put_disk(), which invokes
zloop_free_disk(). The zloop_free_disk() frees the memory allocated for
the zlo pointer. However, after the memory is freed, zloop_ctl_remove()
calls blk_mq_free_tag_set(&zlo->tag_set), which accesses the freed zlo.
Hence the KASAN use-after-free.
zloop_ctl_remove()
put_disk(zlo->disk)
put_device()
kobject_put()
...
zloop_free_disk()
kvfree(zlo)
blk_mq_free_tag_set(&zlo->tag_set)
To avoid the BUG, move the call to blk_mq_free_tag_set(&zlo->tag_set)
from zloop_ctl_remove() into zloop_free_disk(). This ensures that
the tag_set is freed before the call to kvfree(zlo).
References
Impacted products
| Vendor | Product | Version | |
|---|---|---|---|
| linux | linux_kernel | 6.16 |
{
"affected": [
{
"affectedData": [
{
"defaultStatus": "unaffected",
"product": "Linux",
"programFiles": [
"drivers/block/zloop.c"
],
"repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
"vendor": "Linux",
"versions": [
{
"lessThan": "c7c87046b41a9ef28ee7ac476c369da5b5228bc5",
"status": "affected",
"version": "eb0570c7df23c2f32fe899fcdaf8fca9a5ecd51e",
"versionType": "git"
},
{
"lessThan": "765761851d89c772f482494d452e266795460278",
"status": "affected",
"version": "eb0570c7df23c2f32fe899fcdaf8fca9a5ecd51e",
"versionType": "git"
}
]
},
{
"defaultStatus": "affected",
"product": "Linux",
"programFiles": [
"drivers/block/zloop.c"
],
"repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
"vendor": "Linux",
"versions": [
{
"status": "affected",
"version": "6.16"
},
{
"lessThan": "6.16",
"status": "unaffected",
"version": "0",
"versionType": "semver"
},
{
"lessThanOrEqual": "6.16.*",
"status": "unaffected",
"version": "6.16.1",
"versionType": "semver"
},
{
"lessThanOrEqual": "*",
"status": "unaffected",
"version": "6.17",
"versionType": "original_commit_for_fix"
}
]
}
],
"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
}
],
"configurations": [
{
"nodes": [
{
"cpeMatch": [
{
"criteria": "cpe:2.3:o:linux:linux_kernel:6.16:*:*:*:*:*:*:*",
"matchCriteriaId": "D6BFC4F7-7099-4420-AF39-DD1CEABB8DF9",
"vulnerable": true
}
],
"negate": false,
"operator": "OR"
}
]
}
],
"cveTags": [],
"descriptions": [
{
"lang": "en",
"value": "In the Linux kernel, the following vulnerability has been resolved:\n\nzloop: fix KASAN use-after-free of tag set\n\nWhen a zoned loop device, or zloop device, is removed, KASAN enabled\nkernel reports \"BUG KASAN use-after-free\" in blk_mq_free_tag_set(). The\nBUG happens because zloop_ctl_remove() calls put_disk(), which invokes\nzloop_free_disk(). The zloop_free_disk() frees the memory allocated for\nthe zlo pointer. However, after the memory is freed, zloop_ctl_remove()\ncalls blk_mq_free_tag_set(\u0026zlo-\u003etag_set), which accesses the freed zlo.\nHence the KASAN use-after-free.\n\n zloop_ctl_remove()\n put_disk(zlo-\u003edisk)\n put_device()\n kobject_put()\n ...\n zloop_free_disk()\n kvfree(zlo)\n blk_mq_free_tag_set(\u0026zlo-\u003etag_set)\n\nTo avoid the BUG, move the call to blk_mq_free_tag_set(\u0026zlo-\u003etag_set)\nfrom zloop_ctl_remove() into zloop_free_disk(). This ensures that\nthe tag_set is freed before the call to kvfree(zlo)."
},
{
"lang": "es",
"value": "En el kernel de Linux, se ha resuelto la siguiente vulnerabilidad: zloop: correcci\u00f3n del uso tras liberaci\u00f3n de KASAN del conjunto de etiquetas. Al eliminar un dispositivo de bucle zonificado o un dispositivo zloop, el kernel habilitado para KASAN informa \"BUG KASAN use after-free\" en blk_mq_free_tag_set(). El error se produce porque zloop_ctl_remove() llama a put_disk(), que a su vez invoca zloop_free_disk(). zloop_free_disk() libera la memoria asignada al puntero zloop. Sin embargo, una vez liberada la memoria, zloop_ctl_remove() llama a blk_mq_free_tag_set(\u0026amp;zlo-\u0026gt;tag_set), que accede al puntero zloop liberado. De ah\u00ed use-after-free de KASAN. Para evitar el error, mueva la llamada a blk_mq_free_tag_set(\u0026amp;zlo-\u0026gt;tag_set) de zloop_ctl_remove() a zloop_free_disk(). Esto garantiza que el conjunto de etiquetas se libere antes de la llamada a kvfree(zlo)."
}
],
"id": "CVE-2025-38620",
"lastModified": "2026-06-17T09:17:13.900",
"metrics": {
"cvssMetricV31": [
{
"cvssData": {
"attackComplexity": "LOW",
"attackVector": "LOCAL",
"availabilityImpact": "HIGH",
"baseScore": 7.8,
"baseSeverity": "HIGH",
"confidentialityImpact": "HIGH",
"integrityImpact": "HIGH",
"privilegesRequired": "LOW",
"scope": "UNCHANGED",
"userInteraction": "NONE",
"vectorString": "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H",
"version": "3.1"
},
"exploitabilityScore": 1.8,
"impactScore": 5.9,
"source": "nvd@nist.gov",
"type": "Primary"
}
]
},
"published": "2025-08-22T16:15:35.320",
"references": [
{
"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
"tags": [
"Patch"
],
"url": "https://git.kernel.org/stable/c/765761851d89c772f482494d452e266795460278"
},
{
"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
"tags": [
"Patch"
],
"url": "https://git.kernel.org/stable/c/c7c87046b41a9ef28ee7ac476c369da5b5228bc5"
}
],
"sourceIdentifier": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
"vulnStatus": "Analyzed",
"weaknesses": [
{
"description": [
{
"lang": "en",
"value": "CWE-416"
}
],
"source": "nvd@nist.gov",
"type": "Primary"
}
]
}
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|---|
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vulnerability by the CIRCL/vulnerability-attack-technique-classification-roberta-base
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They have not been verified by an analyst and are provided for guidance only.
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The approach is described in our paper Mapping CVEs to MITRE ATT&CK Techniques: A Curated Gold-Set Classifier and the Limits of LLM-Assisted Label Expansion.
Browse all ATT&CK techniques and the vulnerabilities related to each.
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