Vulnerability-Lookup

FKIE_CVE-2026-23114

Vulnerability from fkie_nvd - Published: 2026-02-14 15:16 - Updated: 2026-02-18 17:52

Severity ?

Summary

In the Linux kernel, the following vulnerability has been resolved: arm64/fpsimd: ptrace: Fix SVE writes on !SME systems When SVE is supported but SME is not supported, a ptrace write to the NT_ARM_SVE regset can place the tracee into an invalid state where (non-streaming) SVE register data is stored in FP_STATE_SVE format but TIF_SVE is clear. This can result in a later warning from fpsimd_restore_current_state(), e.g. WARNING: CPU: 0 PID: 7214 at arch/arm64/kernel/fpsimd.c:383 fpsimd_restore_current_state+0x50c/0x748 When this happens, fpsimd_restore_current_state() will set TIF_SVE, placing the task into the correct state. This occurs before any other check of TIF_SVE can possibly occur, as other checks of TIF_SVE only happen while the FPSIMD/SVE/SME state is live. Thus, aside from the warning, there is no functional issue. This bug was introduced during rework to error handling in commit: 9f8bf718f2923 ("arm64/fpsimd: ptrace: Gracefully handle errors") ... where the setting of TIF_SVE was moved into a block which is only executed when system_supports_sme() is true. Fix this by removing the system_supports_sme() check. This ensures that TIF_SVE is set for (SVE-formatted) writes to NT_ARM_SVE, at the cost of unconditionally manipulating the tracee's saved svcr value. The manipulation of svcr is benign and inexpensive, and we already do similar elsewhere (e.g. during signal handling), so I don't think it's worth guarding this with system_supports_sme() checks. Aside from the above, there is no functional change. The 'type' argument to sve_set_common() is only set to ARM64_VEC_SME (in ssve_set())) when system_supports_sme(), so the ARM64_VEC_SME case in the switch statement is still unreachable when !system_supports_sme(). When CONFIG_ARM64_SME=n, the only caller of sve_set_common() is sve_set(), and the compiler can constant-fold for the case where type is ARM64_VEC_SVE, removing the logic for other cases.

References

	URL	Tags
	416baaa9-dc9f-4396-8d5f-8c081fb06d67	https://git.kernel.org/stable/c/128a7494a9f15aad60cc6b7e3546bf481ac54a13
	416baaa9-dc9f-4396-8d5f-8c081fb06d67	https://git.kernel.org/stable/c/4f39984176e7edcaba3432b6c649c6fe93bf2f80

Impacted products

	Vendor	Product	Version

JSON

To clipboard

{
  "cveTags": [],
  "descriptions": [
    {
      "lang": "en",
      "value": "In the Linux kernel, the following vulnerability has been resolved:\n\narm64/fpsimd: ptrace: Fix SVE writes on !SME systems\n\nWhen SVE is supported but SME is not supported, a ptrace write to the\nNT_ARM_SVE regset can place the tracee into an invalid state where\n(non-streaming) SVE register data is stored in FP_STATE_SVE format but\nTIF_SVE is clear. This can result in a later warning from\nfpsimd_restore_current_state(), e.g.\n\n  WARNING: CPU: 0 PID: 7214 at arch/arm64/kernel/fpsimd.c:383 fpsimd_restore_current_state+0x50c/0x748\n\nWhen this happens, fpsimd_restore_current_state() will set TIF_SVE,\nplacing the task into the correct state. This occurs before any other\ncheck of TIF_SVE can possibly occur, as other checks of TIF_SVE only\nhappen while the FPSIMD/SVE/SME state is live. Thus, aside from the\nwarning, there is no functional issue.\n\nThis bug was introduced during rework to error handling in commit:\n\n  9f8bf718f2923 (\"arm64/fpsimd: ptrace: Gracefully handle errors\")\n\n... where the setting of TIF_SVE was moved into a block which is only\nexecuted when system_supports_sme() is true.\n\nFix this by removing the system_supports_sme() check. This ensures that\nTIF_SVE is set for (SVE-formatted) writes to NT_ARM_SVE, at the cost of\nunconditionally manipulating the tracee\u0027s saved svcr value. The\nmanipulation of svcr is benign and inexpensive, and we already do\nsimilar elsewhere (e.g. during signal handling), so I don\u0027t think it\u0027s\nworth guarding this with system_supports_sme() checks.\n\nAside from the above, there is no functional change. The \u0027type\u0027 argument\nto sve_set_common() is only set to ARM64_VEC_SME (in ssve_set())) when\nsystem_supports_sme(), so the ARM64_VEC_SME case in the switch statement\nis still unreachable when !system_supports_sme(). When\nCONFIG_ARM64_SME=n, the only caller of sve_set_common() is sve_set(),\nand the compiler can constant-fold for the case where type is\nARM64_VEC_SVE, removing the logic for other cases."
    },
    {
      "lang": "es",
      "value": "En el kernel de Linux, se ha resuelto la siguiente vulnerabilidad:\n\narm64/fpsimd: ptrace: Corrige escrituras SVE en sistemas sin SME\n\nCuando SVE es compatible pero SME no lo es, una escritura de ptrace al regset NT_ARM_SVE puede colocar al tracee en un estado inv\u00e1lido donde los datos del registro SVE (no streaming) se almacenan en formato FP_STATE_SVE pero TIF_SVE est\u00e1 en cero. Esto puede resultar en una advertencia posterior de fpsimd_restore_current_state(), por ejemplo:\n\n  WARNING: CPU: 0 PID: 7214 at arch/arm64/kernel/fpsimd.c:383 fpsimd_restore_current_state+0x50c/0x748\n\nCuando esto sucede, fpsimd_restore_current_state() establecer\u00e1 TIF_SVE, colocando la tarea en el estado correcto. Esto ocurre antes de que cualquier otra verificaci\u00f3n de TIF_SVE pueda ocurrir, ya que otras verificaciones de TIF_SVE solo suceden mientras el estado FPSIMD/SVE/SME est\u00e1 activo. Por lo tanto, aparte de la advertencia, no hay ning\u00fan problema funcional.\n\nEste error fue introducido durante una revisi\u00f3n del manejo de errores en el commit:\n\n  9f8bf718f2923 (\u0027arm64/fpsimd: ptrace: Manejar errores con gracia\u0027)\n\n... donde la configuraci\u00f3n de TIF_SVE se movi\u00f3 a un bloque que solo se ejecuta cuando system_supports_sme() es verdadero.\n\nEsto se soluciona eliminando la verificaci\u00f3n de system_supports_sme(). Esto asegura que TIF_SVE se establezca para escrituras (con formato SVE) a NT_ARM_SVE, a costa de manipular incondicionalmente el valor svcr guardado del tracee. La manipulaci\u00f3n de svcr es inofensiva y de bajo costo, y ya hacemos algo similar en otros lugares (por ejemplo, durante el manejo de se\u00f1ales), por lo que no creo que valga la pena condicionar esto a verificaciones de system_supports_sme().\n\nAparte de lo anterior, no hay ning\u00fan cambio funcional. El argumento \u0027type\u0027 de sve_set_common() solo se establece en ARM64_VEC_SME (en ssve_set()) cuando system_supports_sme(), por lo que el caso ARM64_VEC_SME en la declaraci\u00f3n switch sigue siendo inalcanzable cuando system_supports_sme() es falso. Cuando CONFIG_ARM64_SME=n, el \u00fanico llamador de sve_set_common() es sve_set(), y el compilador puede realizar plegado de constantes para el caso en que \u0027type\u0027 es ARM64_VEC_SVE, eliminando la l\u00f3gica para otros casos."
    }
  ],
  "id": "CVE-2026-23114",
  "lastModified": "2026-02-18T17:52:44.520",
  "metrics": {},
  "published": "2026-02-14T15:16:06.500",
  "references": [
    {
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
      "url": "https://git.kernel.org/stable/c/128a7494a9f15aad60cc6b7e3546bf481ac54a13"
    },
    {
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
      "url": "https://git.kernel.org/stable/c/4f39984176e7edcaba3432b6c649c6fe93bf2f80"
    }
  ],
  "sourceIdentifier": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
  "vulnStatus": "Awaiting Analysis"
}

CVE-2026-23114 (GCVE-0-2026-23114)

Vulnerability from cvelistv5 – Published: 2026-02-14 15:09 – Updated: 2026-02-14 15:09

Title

arm64/fpsimd: ptrace: Fix SVE writes on !SME systems

Summary

Severity ?

No CVSS data available.

Assigner

Linux

References

URL

Tags

	https://git.kernel.org/stable/c/4f39984176e7edcab…
	https://git.kernel.org/stable/c/128a7494a9f15aad6…

Impacted products

Vendor

Product

Version

Linux

Affected: 9f8bf718f29230e38a048d08fc3063e316cd60c1 , < 4f39984176e7edcaba3432b6c649c6fe93bf2f80 (git)
Affected: 9f8bf718f29230e38a048d08fc3063e316cd60c1 , < 128a7494a9f15aad60cc6b7e3546bf481ac54a13 (git)

Linux

Affected: 6.16
Unaffected: 0 , < 6.16 (semver)
Unaffected: 6.18.8 , ≤ 6.18.* (semver)
Unaffected: 6.19 , ≤ * (original_commit_for_fix)

Show details on NVD website

JSON

To clipboard

{
  "containers": {
    "cna": {
      "affected": [
        {
          "defaultStatus": "unaffected",
          "product": "Linux",
          "programFiles": [
            "arch/arm64/kernel/ptrace.c"
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "vendor": "Linux",
          "versions": [
            {
              "lessThan": "4f39984176e7edcaba3432b6c649c6fe93bf2f80",
              "status": "affected",
              "version": "9f8bf718f29230e38a048d08fc3063e316cd60c1",
              "versionType": "git"
            },
            {
              "lessThan": "128a7494a9f15aad60cc6b7e3546bf481ac54a13",
              "status": "affected",
              "version": "9f8bf718f29230e38a048d08fc3063e316cd60c1",
              "versionType": "git"
            }
          ]
        },
        {
          "defaultStatus": "affected",
          "product": "Linux",
          "programFiles": [
            "arch/arm64/kernel/ptrace.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": "6.18.*",
              "status": "unaffected",
              "version": "6.18.8",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "*",
              "status": "unaffected",
              "version": "6.19",
              "versionType": "original_commit_for_fix"
            }
          ]
        }
      ],
      "cpeApplicability": [
        {
          "nodes": [
            {
              "cpeMatch": [
                {
                  "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                  "versionEndExcluding": "6.18.8",
                  "versionStartIncluding": "6.16",
                  "vulnerable": true
                },
                {
                  "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                  "versionEndExcluding": "6.19",
                  "versionStartIncluding": "6.16",
                  "vulnerable": true
                }
              ],
              "negate": false,
              "operator": "OR"
            }
          ]
        }
      ],
      "descriptions": [
        {
          "lang": "en",
          "value": "In the Linux kernel, the following vulnerability has been resolved:\n\narm64/fpsimd: ptrace: Fix SVE writes on !SME systems\n\nWhen SVE is supported but SME is not supported, a ptrace write to the\nNT_ARM_SVE regset can place the tracee into an invalid state where\n(non-streaming) SVE register data is stored in FP_STATE_SVE format but\nTIF_SVE is clear. This can result in a later warning from\nfpsimd_restore_current_state(), e.g.\n\n  WARNING: CPU: 0 PID: 7214 at arch/arm64/kernel/fpsimd.c:383 fpsimd_restore_current_state+0x50c/0x748\n\nWhen this happens, fpsimd_restore_current_state() will set TIF_SVE,\nplacing the task into the correct state. This occurs before any other\ncheck of TIF_SVE can possibly occur, as other checks of TIF_SVE only\nhappen while the FPSIMD/SVE/SME state is live. Thus, aside from the\nwarning, there is no functional issue.\n\nThis bug was introduced during rework to error handling in commit:\n\n  9f8bf718f2923 (\"arm64/fpsimd: ptrace: Gracefully handle errors\")\n\n... where the setting of TIF_SVE was moved into a block which is only\nexecuted when system_supports_sme() is true.\n\nFix this by removing the system_supports_sme() check. This ensures that\nTIF_SVE is set for (SVE-formatted) writes to NT_ARM_SVE, at the cost of\nunconditionally manipulating the tracee\u0027s saved svcr value. The\nmanipulation of svcr is benign and inexpensive, and we already do\nsimilar elsewhere (e.g. during signal handling), so I don\u0027t think it\u0027s\nworth guarding this with system_supports_sme() checks.\n\nAside from the above, there is no functional change. The \u0027type\u0027 argument\nto sve_set_common() is only set to ARM64_VEC_SME (in ssve_set())) when\nsystem_supports_sme(), so the ARM64_VEC_SME case in the switch statement\nis still unreachable when !system_supports_sme(). When\nCONFIG_ARM64_SME=n, the only caller of sve_set_common() is sve_set(),\nand the compiler can constant-fold for the case where type is\nARM64_VEC_SVE, removing the logic for other cases."
        }
      ],
      "providerMetadata": {
        "dateUpdated": "2026-02-14T15:09:47.048Z",
        "orgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
        "shortName": "Linux"
      },
      "references": [
        {
          "url": "https://git.kernel.org/stable/c/4f39984176e7edcaba3432b6c649c6fe93bf2f80"
        },
        {
          "url": "https://git.kernel.org/stable/c/128a7494a9f15aad60cc6b7e3546bf481ac54a13"
        }
      ],
      "title": "arm64/fpsimd: ptrace: Fix SVE writes on !SME systems",
      "x_generator": {
        "engine": "bippy-1.2.0"
      }
    }
  },
  "cveMetadata": {
    "assignerOrgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
    "assignerShortName": "Linux",
    "cveId": "CVE-2026-23114",
    "datePublished": "2026-02-14T15:09:47.048Z",
    "dateReserved": "2026-01-13T15:37:45.968Z",
    "dateUpdated": "2026-02-14T15:09:47.048Z",
    "state": "PUBLISHED"
  },
  "dataType": "CVE_RECORD",
  "dataVersion": "5.2"
}

Sightings

Author	Source	Type	Date

Nomenclature

Seen: The vulnerability was mentioned, discussed, or observed by the user.
Confirmed: The vulnerability has been validated from an analyst's perspective.
Published Proof of Concept: A public proof of concept is available for this vulnerability.
Exploited: The vulnerability was observed as exploited by the user who reported the sighting.
Patched: The vulnerability was observed as successfully patched by the user who reported the sighting.
Not exploited: The vulnerability was not observed as exploited by the user who reported the sighting.
Not confirmed: The user expressed doubt about the validity of the vulnerability.
Not patched: The vulnerability was not observed as successfully patched by the user who reported the sighting.

Detection rules are retrieved from Rulezet.

Action not permitted

FKIE_CVE-2026-23114

CVE-2026-23114 (GCVE-0-2026-23114)

Tags

Sightings

Nomenclature