CVE-2022-50334
Estado: AnalizadaMedia (5.5)—
In the Linux kernel, the following vulnerability has been resolved:
hugetlbfs: fix null-ptr-deref in hugetlbfs_parse_param()
According to commit "vfs: parse: deal with zero length string value", kernel will set the param->string to null pointer in vfs_parse_fs_string() if fs string has zero length.
Yet the problem is that, hugetlbfs_parse_param() will dereference the param->string, without checking whether it is a null pointer. To be more specific, if hugetlbfs_parse_param() parses an illegal mount parameter, such as "size=,", kernel will constructs struct fs_parameter with null pointer in vfs_parse_fs_string(), then passes this struct fs_parameter to hugetlbfs_parse_param(), which triggers the above null-ptr-deref bug.
Leer descripción completaMostrar menos
This patch solves it by adding sanity check on param->string in hugetlbfs_parse_param().
Detalles técnicos trazas, registros y código del informe original
Syzkaller reports a null-ptr-deref bug as follows: ====================================================== KASAN: null-ptr-deref in range [0x0000000000000000-0x0000000000000007] RIP: 0010:hugetlbfs_parse_param+0x1dd/0x8e0 fs/hugetlbfs/inode.c:1380 [...] Call Trace: <TASK> vfs_parse_fs_param fs/fs_context.c:148 [inline] vfs_parse_fs_param+0x1f9/0x3c0 fs/fs_context.c:129 vfs_parse_fs_string+0xdb/0x170 fs/fs_context.c:191 generic_parse_monolithic+0x16f/0x1f0 fs/fs_context.c:231 do_new_mount fs/namespace.c:3036 [inline] path_mount+0x12de/0x1e20 fs/namespace.c:3370 do_mount fs/namespace.c:3383 [inline] __do_sys_mount fs/namespace.c:3591 [inline] __se_sys_mount fs/namespace.c:3568 [inline] __x64_sys_mount+0x27f/0x300 fs/namespace.c:3568 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x35/0xb0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x63/0xcd [...] </TASK> ======================================================
CVSS
- Versión: 3.1
- Vector: CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H
- Puntuación base: 5.5
Probabilidad de explotación (EPSS)
- Probabilidad de explotación en los próximos 30 días: 0.16%
- Percentil entre todas las CVEs puntuadas: 4
- Fecha de la puntuación: 6/10/2026
EPSS (Exploit Prediction Scoring System, de FIRST) estima la probabilidad de que una vulnerabilidad sea explotada en 30 días. Complementa a CVSS (impacto) y a CISA KEV (explotación confirmada).
Tecnologías afectadas (1)
CWE
- CWE-476
Referencias
- https://git.kernel.org/stable/c/26215b7ee923b9251f7bb12c4e5f09dc465d35f2
- https://git.kernel.org/stable/c/965e8f8ae0f642b5528f5a82b7bcaf15a659d5bd
- https://git.kernel.org/stable/c/9a8862820cbf1f18dca4f3b4c289d88561b3a384
- https://git.kernel.org/stable/c/dcd28191be9bbf307ba51a5b485773a55b0037c4
- https://git.kernel.org/stable/c/f2207145693ae5697a7b59e2add4b92f9e5b0e3c
- https://git.kernel.org/stable/c/fa71639873518e3587632ae58e25e4a96b57fa90
JSON original (NVD)
Mostrar
{
"id": "CVE-2022-50334",
"cveTags": [],
"metrics": {
"cvssMetricV31": [
{
"type": "Primary",
"source": "nvd@nist.gov",
"cvssData": {
"scope": "UNCHANGED",
"version": "3.1",
"baseScore": 5.5,
"attackVector": "LOCAL",
"baseSeverity": "MEDIUM",
"vectorString": "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H",
"integrityImpact": "NONE",
"userInteraction": "NONE",
"attackComplexity": "LOW",
"availabilityImpact": "HIGH",
"privilegesRequired": "LOW",
"confidentialityImpact": "NONE"
},
"impactScore": 3.6,
"exploitabilityScore": 1.8
}
]
},
"affected": [
{
"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
"affectedData": [
{
"repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
"vendor": "Linux",
"product": "Linux",
"versions": [
{
"status": "affected",
"version": "32021982a324dce93b4ae00c06213bf45fb319c8",
"lessThan": "fa71639873518e3587632ae58e25e4a96b57fa90",
"versionType": "git"
},
{
"status": "affected",
"version": "32021982a324dce93b4ae00c06213bf45fb319c8",
"lessThan": "dcd28191be9bbf307ba51a5b485773a55b0037c4",
"versionType": "git"
},
{
"status": "affected",
"version": "32021982a324dce93b4ae00c06213bf45fb319c8",
"lessThan": "9a8862820cbf1f18dca4f3b4c289d88561b3a384",
"versionType": "git"
},
{
"status": "affected",
"version": "32021982a324dce93b4ae00c06213bf45fb319c8",
"lessThan": "965e8f8ae0f642b5528f5a82b7bcaf15a659d5bd",
"versionType": "git"
},
{
"status": "affected",
"version": "32021982a324dce93b4ae00c06213bf45fb319c8",
"lessThan": "f2207145693ae5697a7b59e2add4b92f9e5b0e3c",
"versionType": "git"
},
{
"status": "affected",
"version": "32021982a324dce93b4ae00c06213bf45fb319c8",
"lessThan": "26215b7ee923b9251f7bb12c4e5f09dc465d35f2",
"versionType": "git"
}
],
"programFiles": [
"fs/hugetlbfs/inode.c"
],
"defaultStatus": "unaffected"
},
{
"repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
"vendor": "Linux",
"product": "Linux",
"versions": [
{
"status": "affected",
"version": "5.1"
},
{
"status": "unaffected",
"version": "0",
"lessThan": "5.1",
"versionType": "semver"
},
{
"status": "unaffected",
"version": "5.4.229",
"versionType": "semver",
"lessThanOrEqual": "5.4.*"
},
{
"status": "unaffected",
"version": "5.10.163",
"versionType": "semver",
"lessThanOrEqual": "5.10.*"
},
{
"status": "unaffected",
"version": "5.15.86",
"versionType": "semver",
"lessThanOrEqual": "5.15.*"
},
{
"status": "unaffected",
"version": "6.0.16",
"versionType": "semver",
"lessThanOrEqual": "6.0.*"
},
{
"status": "unaffected",
"version": "6.1.2",
"versionType": "semver",
"lessThanOrEqual": "6.1.*"
},
{
"status": "unaffected",
"version": "6.2",
"versionType": "original_commit_for_fix",
"lessThanOrEqual": "*"
}
],
"programFiles": [
"fs/hugetlbfs/inode.c"
],
"defaultStatus": "affected"
}
]
}
],
"published": "2025-09-15T15:15:45.677",
"references": [
{
"url": "https://git.kernel.org/stable/c/26215b7ee923b9251f7bb12c4e5f09dc465d35f2",
"tags": [
"Patch"
],
"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
},
{
"url": "https://git.kernel.org/stable/c/965e8f8ae0f642b5528f5a82b7bcaf15a659d5bd",
"tags": [
"Patch"
],
"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
},
{
"url": "https://git.kernel.org/stable/c/9a8862820cbf1f18dca4f3b4c289d88561b3a384",
"tags": [
"Patch"
],
"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
},
{
"url": "https://git.kernel.org/stable/c/dcd28191be9bbf307ba51a5b485773a55b0037c4",
"tags": [
"Patch"
],
"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
},
{
"url": "https://git.kernel.org/stable/c/f2207145693ae5697a7b59e2add4b92f9e5b0e3c",
"tags": [
"Patch"
],
"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
},
{
"url": "https://git.kernel.org/stable/c/fa71639873518e3587632ae58e25e4a96b57fa90",
"tags": [
"Patch"
],
"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
}
],
"vulnStatus": "Analyzed",
"weaknesses": [
{
"type": "Primary",
"source": "nvd@nist.gov",
"description": [
{
"lang": "en",
"value": "CWE-476"
}
]
}
],
"descriptions": [
{
"lang": "en",
"value": "In the Linux kernel, the following vulnerability has been resolved:\n\nhugetlbfs: fix null-ptr-deref in hugetlbfs_parse_param()\n\nSyzkaller reports a null-ptr-deref bug as follows:\n======================================================\nKASAN: null-ptr-deref in range [0x0000000000000000-0x0000000000000007]\nRIP: 0010:hugetlbfs_parse_param+0x1dd/0x8e0 fs/hugetlbfs/inode.c:1380\n[...]\nCall Trace:\n <TASK>\n vfs_parse_fs_param fs/fs_context.c:148 [inline]\n vfs_parse_fs_param+0x1f9/0x3c0 fs/fs_context.c:129\n vfs_parse_fs_string+0xdb/0x170 fs/fs_context.c:191\n generic_parse_monolithic+0x16f/0x1f0 fs/fs_context.c:231\n do_new_mount fs/namespace.c:3036 [inline]\n path_mount+0x12de/0x1e20 fs/namespace.c:3370\n do_mount fs/namespace.c:3383 [inline]\n __do_sys_mount fs/namespace.c:3591 [inline]\n __se_sys_mount fs/namespace.c:3568 [inline]\n __x64_sys_mount+0x27f/0x300 fs/namespace.c:3568\n do_syscall_x64 arch/x86/entry/common.c:50 [inline]\n do_syscall_64+0x35/0xb0 arch/x86/entry/common.c:80\n entry_SYSCALL_64_after_hwframe+0x63/0xcd\n [...]\n </TASK>\n======================================================\n\nAccording to commit \"vfs: parse: deal with zero length string value\",\nkernel will set the param->string to null pointer in vfs_parse_fs_string()\nif fs string has zero length.\n\nYet the problem is that, hugetlbfs_parse_param() will dereference the\nparam->string, without checking whether it is a null pointer. To be more\nspecific, if hugetlbfs_parse_param() parses an illegal mount parameter,\nsuch as \"size=,\", kernel will constructs struct fs_parameter with null\npointer in vfs_parse_fs_string(), then passes this struct fs_parameter to\nhugetlbfs_parse_param(), which triggers the above null-ptr-deref bug.\n\nThis patch solves it by adding sanity check on param->string\nin hugetlbfs_parse_param()."
}
],
"lastModified": "2026-06-17T05:23:15.393",
"configurations": [
{
"nodes": [
{
"negate": false,
"cpeMatch": [
{
"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
"vulnerable": true,
"matchCriteriaId": "35BD75DA-D55E-4B66-8E0E-4931F67E1163",
"versionEndExcluding": "5.4.229"
},
{
"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
"vulnerable": true,
"matchCriteriaId": "D05D31FC-BD74-4F9E-B1D8-9CED62BE6F65",
"versionEndExcluding": "5.10.163",
"versionStartIncluding": "5.5"
},
{
"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
"vulnerable": true,
"matchCriteriaId": "47237296-55D1-4ED4-8075-D00FC85A61EE",
"versionEndExcluding": "5.15.86",
"versionStartIncluding": "5.11"
},
{
"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
"vulnerable": true,
"matchCriteriaId": "C720A569-3D93-4D77-95F6-E2B3A3267D9F",
"versionEndExcluding": "6.0.16",
"versionStartIncluding": "5.16"
},
{
"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
"vulnerable": true,
"matchCriteriaId": "77239F4B-6BB2-4B9E-A654-36A52396116C",
"versionEndExcluding": "6.1.2",
"versionStartIncluding": "6.1"
}
],
"operator": "OR"
}
]
}
],
"sourceIdentifier": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
}