CVE-2025-40078
Full vulnerability record from the local CVENow database.
Description
In the Linux kernel, the following vulnerability has been resolved: bpf: Explicitly check accesses to bpf_sock_addr Syzkaller found a kernel warning on the following sock_addr program: 0: r0 = 0 1: r2 = *(u32 *)(r1 +60) 2: exit which triggers: verifier bug: error during ctx access conversion (0) This is happening because offset 60 in bpf_sock_addr corresponds to an implicit padding of 4 bytes, right after msg_src_ip4. Access to this padding isn't rejected in sock_addr_is_valid_access and it thus later fails to convert the access. This patch fixes it by explicitly checking the various fields of bpf_sock_addr in sock_addr_is_valid_access. I checked the other ctx structures and is_valid_access functions and didn't find any other similar cases. Other cases of (properly handled) padding are covered in new tests in a subsequent patch.
Severity
Not scored
CVSS score
Not available
Vulnerability status
Deferred
Source identifier
416baaa9-dc9f-4396-8d5f-8c081fb06d67
Published
2025-10-28 12:15:42.360000
Last modified
2026-10-19 21:10:00.160000
View original CVE JSON
{
"id": "CVE-2025-40078",
"sourceIdentifier": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
"published": "2025-10-28T12:15:42.360",
"lastModified": "2026-10-19T21:10:00.160",
"vulnStatus": "Deferred",
"cveTags": [],
"descriptions": [
{
"lang": "en",
"value": "In the Linux kernel, the following vulnerability has been resolved:\n\nbpf: Explicitly check accesses to bpf_sock_addr\n\nSyzkaller found a kernel warning on the following sock_addr program:\n\n 0: r0 = 0\n 1: r2 = *(u32 *)(r1 +60)\n 2: exit\n\nwhich triggers:\n\n verifier bug: error during ctx access conversion (0)\n\nThis is happening because offset 60 in bpf_sock_addr corresponds to an\nimplicit padding of 4 bytes, right after msg_src_ip4. Access to this\npadding isn't rejected in sock_addr_is_valid_access and it thus later\nfails to convert the access.\n\nThis patch fixes it by explicitly checking the various fields of\nbpf_sock_addr in sock_addr_is_valid_access.\n\nI checked the other ctx structures and is_valid_access functions and\ndidn't find any other similar cases. Other cases of (properly handled)\npadding are covered in new tests in a subsequent patch."
},
{
"lang": "es",
"value": "En el kernel de Linux, la siguiente vulnerabilidad ha sido resuelta:\n\nbpf: Comprobar explícitamente los accesos a bpf_sock_addr\n\nSyzkaller encontró una advertencia del kernel en el siguiente programa sock_addr:\n\n 0: r0 = 0\n 1: r2 = *(u32 *)(r1 +60)\n 2: exit\n\nlo que activa:\n\n error del verificador: error durante la conversión de acceso a ctx (0)\n\nEsto está ocurriendo porque el desplazamiento 60 en bpf_sock_addr corresponde a un relleno implícito de 4 bytes, justo después de msg_src_ip4. El acceso a este relleno no es rechazado en sock_addr_is_valid_access y, por lo tanto, más tarde falla en convertir el acceso.\n\nEste parche lo soluciona comprobando explícitamente los diversos campos de bpf_sock_addr en sock_addr_is_valid_access.\n\nRevisé las otras estructuras ctx y las funciones is_valid_access y no encontré ningún otro caso similar. Otros casos de relleno (manejado correctamente) están cubiertos en nuevas pruebas en un parche posterior."
}
],
"affected": [
{
"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
"affectedData": [
{
"vendor": "Linux",
"product": "Linux",
"defaultStatus": "unaffected",
"programFiles": [
"net/core/filter.c"
],
"repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
"versions": [
{
"version": "1cedee13d25ab118d325f95588c1a084e9317229",
"lessThan": "de44cdc50d2dce8718cb57deddf9cf1be9a7759f",
"versionType": "git",
"status": "affected"
},
{
"version": "1cedee13d25ab118d325f95588c1a084e9317229",
"lessThan": "76e04bbb4296fb6eac084dbfc27e02ccc744db3e",
"versionType": "git",
"status": "affected"
},
{
"version": "1cedee13d25ab118d325f95588c1a084e9317229",
"lessThan": "6d8b1a21fd5c34622b0c3893c61e4a38d8ba53ec",
"versionType": "git",
"status": "affected"
},
{
"version": "1cedee13d25ab118d325f95588c1a084e9317229",
"lessThan": "4f00858cd9bbbdf67159e28b85a8ca9e77c83622",
"versionType": "git",
"status": "affected"
},
{
"version": "1cedee13d25ab118d325f95588c1a084e9317229",
"lessThan": "cdeafacb4f9ff261a96baef519e29480fd7b1019",
"versionType": "git",
"status": "affected"
},
{
"version": "1cedee13d25ab118d325f95588c1a084e9317229",
"lessThan": "fe9d33f0470350558cb08cecb54cf2267b3a45d2",
"versionType": "git",
"status": "affected"
},
{
"version": "1cedee13d25ab118d325f95588c1a084e9317229",
"lessThan": "ad8b4fe5617e3c85fc23267f02500c4f3bf0ff69",
"versionType": "git",
"status": "affected"
},
{
"version": "1cedee13d25ab118d325f95588c1a084e9317229",
"lessThan": "6fabca2fc94d33cdf7ec102058983b086293395f",
"versionType": "git",
"status": "affected"
}
]
},
{
"vendor": "Linux",
"product": "Linux",
"defaultStatus": "affected",
"programFiles": [
"net/core/filter.c"
],
"repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
"versions": [
{
"version": "4.18",
"status": "affected"
},
{
"version": "0",
"lessThan": "4.18",
"versionType": "semver",
"status": "unaffected"
},
{
"version": "5.4.301",
"lessThanOrEqual": "5.4.*",
"versionType": "semver",
"status": "unaffected"
},
{
"version": "5.10.246",
"lessThanOrEqual": "5.10.*",
"versionType": "semver",
"status": "unaffected"
},
{
"version": "5.15.195",
"lessThanOrEqual": "5.15.*",
"versionType": "semver",
"status": "unaffected"
},
{
"version": "6.1.156",
"lessThanOrEqual": "6.1.*",
"versionType": "semver",
"status": "unaffected"
},
{
"version": "6.6.112",
"lessThanOrEqual": "6.6.*",
"versionType": "semver",
"status": "unaffected"
},
{
"version": "6.12.53",
"lessThanOrEqual": "6.12.*",
"versionType": "semver",
"status": "unaffected"
},
{
"version": "6.17.3",
"lessThanOrEqual": "6.17.*",
"versionType": "semver",
"status": "unaffected"
},
{
"version": "6.18",
"lessThanOrEqual": "*",
"versionType": "original_commit_for_fix",
"status": "unaffected"
}
]
}
]
},
{
"source": "0b142b55-0307-4c5a-b3c9-f314f3fb7c5e",
"affectedData": [
{
"vendor": "Siemens",
"product": "SIMATIC S7-1500 CPU 1518-4 PN/DP MFP",
"defaultStatus": "unknown",
"versions": [
{
"version": "V3.1.6",
"lessThan": "*",
"versionType": "custom",
"status": "affected"
}
]
},
{
"vendor": "Siemens",
"product": "SIMATIC S7-1500 CPU 1518-4 PN/DP MFP",
"defaultStatus": "unknown",
"versions": [
{
"version": "V3.1.7",
"lessThan": "*",
"versionType": "custom",
"status": "affected"
}
]
},
{
"vendor": "Siemens",
"product": "SIMATIC S7-1500 CPU 1518-4 PN/DP MFP",
"defaultStatus": "unknown",
"versions": [
{
"version": "V3.1.6",
"lessThan": "*",
"versionType": "custom",
"status": "affected"
}
]
},
{
"vendor": "Siemens",
"product": "SIMATIC S7-1500 CPU 1518-4 PN/DP MFP",
"defaultStatus": "unknown",
"versions": [
{
"version": "V3.1.7",
"lessThan": "*",
"versionType": "custom",
"status": "affected"
}
]
},
{
"vendor": "Siemens",
"product": "SIMATIC S7-1500 CPU 1518F-4 PN/DP MFP",
"defaultStatus": "unknown",
"versions": [
{
"version": "V3.1.6",
"lessThan": "*",
"versionType": "custom",
"status": "affected"
}
]
},
{
"vendor": "Siemens",
"product": "SIMATIC S7-1500 CPU 1518F-4 PN/DP MFP",
"defaultStatus": "unknown",
"versions": [
{
"version": "V3.1.7",
"lessThan": "*",
"versionType": "custom",
"status": "affected"
}
]
},
{
"vendor": "Siemens",
"product": "SIMATIC S7-1500 CPU 1518F-4 PN/DP MFP",
"defaultStatus": "unknown",
"versions": [
{
"version": "V3.1.6",
"lessThan": "*",
"versionType": "custom",
"status": "affected"
}
]
},
{
"vendor": "Siemens",
"product": "SIMATIC S7-1500 CPU 1518F-4 PN/DP MFP",
"defaultStatus": "unknown",
"versions": [
{
"version": "V3.1.7",
"lessThan": "*",
"versionType": "custom",
"status": "affected"
}
]
},
{
"vendor": "Siemens",
"product": "SIPLUS S7-1500 CPU 1518-4 PN/DP MFP",
"defaultStatus": "unknown",
"versions": [
{
"version": "V3.1.6",
"lessThan": "*",
"versionType": "custom",
"status": "affected"
}
]
},
{
"vendor": "Siemens",
"product": "SIPLUS S7-1500 CPU 1518-4 PN/DP MFP",
"defaultStatus": "unknown",
"versions": [
{
"version": "V3.1.7",
"lessThan": "*",
"versionType": "custom",
"status": "affected"
}
]
}
]
}
],
"metrics": {},
"references": [
{
"url": "https://git.kernel.org/stable/c/4f00858cd9bbbdf67159e28b85a8ca9e77c83622",
"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
},
{
"url": "https://git.kernel.org/stable/c/6d8b1a21fd5c34622b0c3893c61e4a38d8ba53ec",
"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
},
{
"url": "https://git.kernel.org/stable/c/6fabca2fc94d33cdf7ec102058983b086293395f",
"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
},
{
"url": "https://git.kernel.org/stable/c/76e04bbb4296fb6eac084dbfc27e02ccc744db3e",
"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
},
{
"url": "https://git.kernel.org/stable/c/ad8b4fe5617e3c85fc23267f02500c4f3bf0ff69",
"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
},
{
"url": "https://git.kernel.org/stable/c/cdeafacb4f9ff261a96baef519e29480fd7b1019",
"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
},
{
"url": "https://git.kernel.org/stable/c/de44cdc50d2dce8718cb57deddf9cf1be9a7759f",
"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
},
{
"url": "https://git.kernel.org/stable/c/fe9d33f0470350558cb08cecb54cf2267b3a45d2",
"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
},
{
"url": "https://cert-portal.siemens.com/productcert/html/ssa-019113.html",
"source": "0b142b55-0307-4c5a-b3c9-f314f3fb7c5e"
},
{
"url": "https://cert-portal.siemens.com/productcert/html/ssa-457936.html",
"source": "0b142b55-0307-4c5a-b3c9-f314f3fb7c5e"
}
]
}