CVE-2026-23067
Full vulnerability record from the local CVENow database.
Description
In the Linux kernel, the following vulnerability has been resolved: iommu/io-pgtable-arm: fix size_t signedness bug in unmap path __arm_lpae_unmap() returns size_t but was returning -ENOENT (negative error code) when encountering an unmapped PTE. Since size_t is unsigned, -ENOENT (typically -2) becomes a huge positive value (0xFFFFFFFFFFFFFFFE on 64-bit systems). This corrupted value propagates through the call chain: __arm_lpae_unmap() returns -ENOENT as size_t -> arm_lpae_unmap_pages() returns it -> __iommu_unmap() adds it to iova address -> iommu_pgsize() triggers BUG_ON due to corrupted iova This can cause IOVA address overflow in __iommu_unmap() loop and trigger BUG_ON in iommu_pgsize() from invalid address alignment. Fix by returning 0 instead of -ENOENT. The WARN_ON already signals the error condition, and returning 0 (meaning "nothing unmapped") is the correct semantic for size_t return type. This matches the behavior of other io-pgtable implementations (io-pgtable-arm-v7s, io-pgtable-dart) which return 0 on error conditions.
Severity
MEDIUM
CVSS score
5.5
(v3.1)
Vulnerability status
Analyzed
Source identifier
416baaa9-dc9f-4396-8d5f-8c081fb06d67
Published
2026-02-04 17:16:17.403000
Last modified
2026-11-05 22:18:01.100000
View original CVE JSON
{
"id": "CVE-2026-23067",
"sourceIdentifier": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
"published": "2026-02-04T17:16:17.403",
"lastModified": "2026-11-05T22:18:01.100",
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{
"lang": "en",
"value": "In the Linux kernel, the following vulnerability has been resolved:\n\niommu/io-pgtable-arm: fix size_t signedness bug in unmap path\n\n__arm_lpae_unmap() returns size_t but was returning -ENOENT (negative\nerror code) when encountering an unmapped PTE. Since size_t is unsigned,\n-ENOENT (typically -2) becomes a huge positive value (0xFFFFFFFFFFFFFFFE\non 64-bit systems).\n\nThis corrupted value propagates through the call chain:\n __arm_lpae_unmap() returns -ENOENT as size_t\n -> arm_lpae_unmap_pages() returns it\n -> __iommu_unmap() adds it to iova address\n -> iommu_pgsize() triggers BUG_ON due to corrupted iova\n\nThis can cause IOVA address overflow in __iommu_unmap() loop and\ntrigger BUG_ON in iommu_pgsize() from invalid address alignment.\n\nFix by returning 0 instead of -ENOENT. The WARN_ON already signals\nthe error condition, and returning 0 (meaning \"nothing unmapped\")\nis the correct semantic for size_t return type. This matches the\nbehavior of other io-pgtable implementations (io-pgtable-arm-v7s,\nio-pgtable-dart) which return 0 on error conditions."
},
{
"lang": "es",
"value": "En el kernel de Linux, la siguiente vulnerabilidad ha sido resuelta:\n\niommu/io-pgtable-arm: corrección de error de signo de size_t en la ruta de desmapeo\n\n__arm_lpae_unmap() devuelve size_t pero estaba devolviendo -ENOENT (código de error negativo) al encontrar una PTE no mapeada. Dado que size_t no tiene signo, -ENOENT (típicamente -2) se convierte en un valor positivo enorme (0xFFFFFFFFFFFFFFFE en sistemas de 64 bits).\n\nEste valor corrupto se propaga a través de la cadena de llamadas:\n __arm_lpae_unmap() devuelve -ENOENT como size_t\n -> arm_lpae_unmap_pages() lo devuelve\n -> __iommu_unmap() lo añade a la dirección iova\n -> iommu_pgsize() activa BUG_ON debido a iova corrupta\n\nEsto puede causar un desbordamiento de dirección IOVA en el bucle de __iommu_unmap() y activar BUG_ON en iommu_pgsize() por una alineación de dirección inválida.\n\nSe corrige devolviendo 0 en lugar de -ENOENT. El WARN_ON ya señala la condición de error, y devolver 0 (que significa 'nada desmapeado') es la semántica correcta para el tipo de retorno size_t. Esto coincide con el comportamiento de otras implementaciones de io-pgtable (io-pgtable-arm-v7s, io-pgtable-dart) que devuelven 0 en condiciones de error."
}
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"baseScore": 5.5,
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"attackVector": "LOCAL",
"attackComplexity": "LOW",
"privilegesRequired": "LOW",
"userInteraction": "NONE",
"scope": "UNCHANGED",
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"integrityImpact": "NONE",
"availabilityImpact": "HIGH"
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"id": "CVE-2026-23067",
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"description": [
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