fkie_cve-2024-42293
Vulnerability from fkie_nvd
Published
2024-08-17 09:15
Modified
2025-09-29 15:19
Severity ?
Summary
In the Linux kernel, the following vulnerability has been resolved:
arm64: mm: Fix lockless walks with static and dynamic page-table folding
Lina reports random oopsen originating from the fast GUP code when
16K pages are used with 4-level page-tables, the fourth level being
folded at runtime due to lack of LPA2.
In this configuration, the generic implementation of
p4d_offset_lockless() will return a 'p4d_t *' corresponding to the
'pgd_t' allocated on the stack of the caller, gup_fast_pgd_range().
This is normally fine, but when the fourth level of page-table is folded
at runtime, pud_offset_lockless() will offset from the address of the
'p4d_t' to calculate the address of the PUD in the same page-table page.
This results in a stray stack read when the 'p4d_t' has been allocated
on the stack and can send the walker into the weeds.
Fix the problem by providing our own definition of p4d_offset_lockless()
when CONFIG_PGTABLE_LEVELS <= 4 which returns the real page-table
pointer rather than the address of the local stack variable.
References
Impacted products
| Vendor | Product | Version | |
|---|---|---|---|
| linux | linux_kernel | * |
{
"configurations": [
{
"nodes": [
{
"cpeMatch": [
{
"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
"matchCriteriaId": "3332351F-A9A1-4AD4-BEDB-5B3BBD5B7279",
"versionEndExcluding": "6.10.3",
"versionStartIncluding": "6.9",
"vulnerable": true
}
],
"negate": false,
"operator": "OR"
}
]
}
],
"cveTags": [],
"descriptions": [
{
"lang": "en",
"value": "In the Linux kernel, the following vulnerability has been resolved:\n\narm64: mm: Fix lockless walks with static and dynamic page-table folding\n\nLina reports random oopsen originating from the fast GUP code when\n16K pages are used with 4-level page-tables, the fourth level being\nfolded at runtime due to lack of LPA2.\n\nIn this configuration, the generic implementation of\np4d_offset_lockless() will return a \u0027p4d_t *\u0027 corresponding to the\n\u0027pgd_t\u0027 allocated on the stack of the caller, gup_fast_pgd_range().\nThis is normally fine, but when the fourth level of page-table is folded\nat runtime, pud_offset_lockless() will offset from the address of the\n\u0027p4d_t\u0027 to calculate the address of the PUD in the same page-table page.\nThis results in a stray stack read when the \u0027p4d_t\u0027 has been allocated\non the stack and can send the walker into the weeds.\n\nFix the problem by providing our own definition of p4d_offset_lockless()\nwhen CONFIG_PGTABLE_LEVELS \u003c= 4 which returns the real page-table\npointer rather than the address of the local stack variable."
},
{
"lang": "es",
"value": "En el kernel de Linux, se ha resuelto la siguiente vulnerabilidad: arm64: mm: corrige recorridos sin bloqueo con plegado de tablas de p\u00e1ginas est\u00e1ticas y din\u00e1micas. Lina informa oopsen aleatorios que se originan en el c\u00f3digo GUP r\u00e1pido cuando se utilizan p\u00e1ginas de 16 KB con tablas de p\u00e1ginas de 4 niveles. el cuarto nivel se pliega en tiempo de ejecuci\u00f3n debido a la falta de LPA2. En esta configuraci\u00f3n, la implementaci\u00f3n gen\u00e9rica de p4d_offset_lockless() devolver\u00e1 un \u0027p4d_t *\u0027 correspondiente al \u0027pgd_t\u0027 asignado en la pila de la persona que llama, gup_fast_pgd_range(). Esto normalmente est\u00e1 bien, pero cuando el cuarto nivel de la tabla de p\u00e1ginas se pliega en tiempo de ejecuci\u00f3n, pud_offset_lockless() se desplazar\u00e1 de la direcci\u00f3n de \u0027p4d_t\u0027 para calcular la direcci\u00f3n del PUD en la misma p\u00e1gina de la tabla de p\u00e1ginas. Esto da como resultado una lectura de pila perdida cuando el \u0027p4d_t\u0027 se ha asignado en la pila y puede enviar al caminante hacia la maleza. Solucione el problema proporcionando nuestra propia definici\u00f3n de p4d_offset_lockless() cuando CONFIG_PGTABLE_LEVELS \u0026lt;= 4, que devuelve el puntero de la tabla de p\u00e1ginas real en lugar de la direcci\u00f3n de la variable de pila local."
}
],
"id": "CVE-2024-42293",
"lastModified": "2025-09-29T15:19:10.967",
"metrics": {
"cvssMetricV31": [
{
"cvssData": {
"attackComplexity": "LOW",
"attackVector": "LOCAL",
"availabilityImpact": "HIGH",
"baseScore": 5.5,
"baseSeverity": "MEDIUM",
"confidentialityImpact": "NONE",
"integrityImpact": "NONE",
"privilegesRequired": "LOW",
"scope": "UNCHANGED",
"userInteraction": "NONE",
"vectorString": "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H",
"version": "3.1"
},
"exploitabilityScore": 1.8,
"impactScore": 3.6,
"source": "nvd@nist.gov",
"type": "Primary"
}
]
},
"published": "2024-08-17T09:15:09.867",
"references": [
{
"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
"tags": [
"Patch"
],
"url": "https://git.kernel.org/stable/c/36639013b3462c06ff8e3400a427f775b4fc97f5"
},
{
"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
"tags": [
"Patch"
],
"url": "https://git.kernel.org/stable/c/78672d49d3eebbcda3589f4d6e589caf357c5a59"
}
],
"sourceIdentifier": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
"vulnStatus": "Analyzed",
"weaknesses": [
{
"description": [
{
"lang": "en",
"value": "CWE-125"
}
],
"source": "nvd@nist.gov",
"type": "Primary"
}
]
}
Loading…
Loading…
Sightings
| Author | Source | Type | Date |
|---|
Nomenclature
- Seen: The vulnerability was mentioned, discussed, or seen somewhere by the user.
- Confirmed: The vulnerability is confirmed from an analyst perspective.
- Exploited: This vulnerability was exploited and seen by the user reporting the sighting.
- Patched: This vulnerability was successfully patched by the user reporting the sighting.
- Not exploited: This vulnerability was not exploited or seen by the user reporting the sighting.
- Not confirmed: The user expresses doubt about the veracity of the vulnerability.
- Not patched: This vulnerability was not successfully patched by the user reporting the sighting.
Loading…