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FKIE_CVE-2026-93254

Vulnerability from fkie_nvd - Published: 2026-09-24 16:17 - Updated: 2026-09-24 16:17

Severity

Summary

In the Linux kernel, the following vulnerability has been resolved: arm64: entry: Avoid unnecessary local_irq_disable() on kernel exit Currently, when exiting to kernel mode, we attempt involuntary preemption. The preemption logic expects IRQs to be disabled, which is why we call local_irq_disable() before attempting preemption. However, depending on the context, local_irq_disable() may be unnecessary: - __el1_irq(), the non-NMI EL1 IRQ path, already has IRQs disabled, so local_irq_disable() is redundant. - irqentry_exit_to_kernel_mode_preempt() immediately returns when exiting from an NMI-like context, so calling local_irq_disable() beforehand is unnecessary work. Furthermore, it confuses the pNMI state tracking when we are in a context with interrupts disabled and the GIC_PRIO_PSR_I_SET bit is set in the PMR, leading to a warning when CONFIG_ARM64_DEBUG_PRIORITY_MASKING=y: WARNING: ./arch/arm64/include/asm/irqflags.h:63 at arm64_exit_to_kernel_mode+0xb8/0xc0, CPU#40: retsnoop/31805 CPU: 40 UID: 0 PID: 31805 Comm: retsnoop Not tainted 7.2.0-rc6-next-20260805 #7 PREEMPTLAZY pstate: 234013c9 (nzCv DAIF +PAN -UAO +TCO +DIT +SSBS BTYPE=--) pc : arm64_exit_to_kernel_mode (arch/arm64/kernel/entry-common.c:63) lr : el1_abort (arch/arm64/kernel/entry-common.c:323) pmr: 000000f0 Call trace: arm64_exit_to_kernel_mode (arch/arm64/kernel/entry-common.c:63) (P) el1_abort (arch/arm64/kernel/entry-common.c:323) el1h_64_sync_handler (arch/arm64/kernel/entry-common.c:449) el1h_64_sync (arch/arm64/kernel/entry.S:589) [...] Split arm64_exit_to_kernel_mode() into preempt, non-preempt, and dispatch parts so that we can avoid this extra work where it is not needed and avoid breaking the pNMI tracking logic.

References

	URL	Tags
	416baaa9-dc9f-4396-8d5f-8c081fb06d67	https://git.kernel.org/stable/c/39aebe0e89469c2904e60b1e977e0d4dbf33326b
	416baaa9-dc9f-4396-8d5f-8c081fb06d67	https://git.kernel.org/stable/c/49a61174186bed25d439ff37400c7ce5e3603e73

Impacted products

	Vendor	Product	Version

JSON

To clipboard

{
  "affected": [
    {
      "affectedData": [
        {
          "defaultStatus": "unaffected",
          "product": "Linux",
          "programFiles": [
            "arch/arm64/kernel/entry-common.c"
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "vendor": "Linux",
          "versions": [
            {
              "lessThan": "49a61174186bed25d439ff37400c7ce5e3603e73",
              "status": "affected",
              "version": "ae654112eac05f316ef31587fc55e4d7160d0086",
              "versionType": "git"
            },
            {
              "lessThan": "39aebe0e89469c2904e60b1e977e0d4dbf33326b",
              "status": "affected",
              "version": "ae654112eac05f316ef31587fc55e4d7160d0086",
              "versionType": "git"
            }
          ]
        },
        {
          "defaultStatus": "affected",
          "product": "Linux",
          "programFiles": [
            "arch/arm64/kernel/entry-common.c"
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "vendor": "Linux",
          "versions": [
            {
              "status": "affected",
              "version": "7.1"
            },
            {
              "lessThan": "7.1",
              "status": "unaffected",
              "version": "0",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "7.2.*",
              "status": "unaffected",
              "version": "7.2.6",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "*",
              "status": "unaffected",
              "version": "7.3-rc1",
              "versionType": "original_commit_for_fix"
            }
          ]
        }
      ],
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
    }
  ],
  "cveTags": [],
  "descriptions": [
    {
      "lang": "en",
      "value": "In the Linux kernel, the following vulnerability has been resolved:\n\narm64: entry: Avoid unnecessary local_irq_disable() on kernel exit\n\nCurrently, when exiting to kernel mode, we attempt involuntary\npreemption. The preemption logic expects IRQs to be disabled, which is\nwhy we call local_irq_disable() before attempting preemption.\n\nHowever, depending on the context, local_irq_disable() may be\nunnecessary:\n\n- __el1_irq(), the non-NMI EL1 IRQ path, already has IRQs disabled, so\n  local_irq_disable() is redundant.\n\n- irqentry_exit_to_kernel_mode_preempt() immediately returns when\n  exiting from an NMI-like context, so calling local_irq_disable()\n  beforehand is unnecessary work.\n\nFurthermore, it confuses the pNMI state tracking when we are in a\ncontext with interrupts disabled and the GIC_PRIO_PSR_I_SET bit is set\nin the PMR, leading to a warning when\nCONFIG_ARM64_DEBUG_PRIORITY_MASKING=y:\n\n     WARNING: ./arch/arm64/include/asm/irqflags.h:63 at arm64_exit_to_kernel_mode+0xb8/0xc0, CPU#40: retsnoop/31805\n     CPU: 40 UID: 0 PID: 31805 Comm: retsnoop Not tainted 7.2.0-rc6-next-20260805 #7 PREEMPTLAZY\n     pstate: 234013c9 (nzCv DAIF +PAN -UAO +TCO +DIT +SSBS BTYPE=--)\n     pc : arm64_exit_to_kernel_mode (arch/arm64/kernel/entry-common.c:63)\n     lr : el1_abort (arch/arm64/kernel/entry-common.c:323)\n     pmr: 000000f0\n     Call trace:\n      arm64_exit_to_kernel_mode (arch/arm64/kernel/entry-common.c:63) (P)\n      el1_abort (arch/arm64/kernel/entry-common.c:323)\n      el1h_64_sync_handler (arch/arm64/kernel/entry-common.c:449)\n      el1h_64_sync (arch/arm64/kernel/entry.S:589)\n      [...]\n\nSplit arm64_exit_to_kernel_mode() into preempt, non-preempt, and\ndispatch parts so that we can avoid this extra work where it is not\nneeded and avoid breaking the pNMI tracking logic."
    }
  ],
  "id": "CVE-2026-93254",
  "lastModified": "2026-09-24T16:17:21.807",
  "metrics": {},
  "published": "2026-09-24T16:17:21.807",
  "references": [
    {
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
      "url": "https://git.kernel.org/stable/c/39aebe0e89469c2904e60b1e977e0d4dbf33326b"
    },
    {
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
      "url": "https://git.kernel.org/stable/c/49a61174186bed25d439ff37400c7ce5e3603e73"
    }
  ],
  "sourceIdentifier": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
  "vulnStatus": "Received"
}

CVE-2026-93254 (GCVE-0-2026-93254)

Vulnerability from cvelistv5 – Published: 2026-09-24 15:51 – Updated: 2026-09-24 15:51

Title

arm64: entry: Avoid unnecessary local_irq_disable() on kernel exit

Summary

Severity

No CVSS data available.

Assigner

Linux mitre root

References

2 references

URL	Tags
https://git.kernel.org/stable/c/49a61174186bed25d…
https://git.kernel.org/stable/c/39aebe0e89469c290…

Impacted products

2 products

Vendor	Product	Version
Linux	Linux	Affected: ae654112eac05f316ef31587fc55e4d7160d0086 , < 49a61174186bed25d439ff37400c7ce5e3603e73 (git) Affected: ae654112eac05f316ef31587fc55e4d7160d0086 , < 39aebe0e89469c2904e60b1e977e0d4dbf33326b (git)
Linux	Linux	Affected: 7.1 Unaffected: 0 , < 7.1 (semver) Unaffected: 7.2.6 , ≤ 7.2.* (semver) Unaffected: 7.3-rc1 , ≤ * (original_commit_for_fix)

Show details on NVD website

JSON

To clipboard

{
  "containers": {
    "cna": {
      "affected": [
        {
          "defaultStatus": "unaffected",
          "product": "Linux",
          "programFiles": [
            "arch/arm64/kernel/entry-common.c"
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "vendor": "Linux",
          "versions": [
            {
              "lessThan": "49a61174186bed25d439ff37400c7ce5e3603e73",
              "status": "affected",
              "version": "ae654112eac05f316ef31587fc55e4d7160d0086",
              "versionType": "git"
            },
            {
              "lessThan": "39aebe0e89469c2904e60b1e977e0d4dbf33326b",
              "status": "affected",
              "version": "ae654112eac05f316ef31587fc55e4d7160d0086",
              "versionType": "git"
            }
          ]
        },
        {
          "defaultStatus": "affected",
          "product": "Linux",
          "programFiles": [
            "arch/arm64/kernel/entry-common.c"
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "vendor": "Linux",
          "versions": [
            {
              "status": "affected",
              "version": "7.1"
            },
            {
              "lessThan": "7.1",
              "status": "unaffected",
              "version": "0",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "7.2.*",
              "status": "unaffected",
              "version": "7.2.6",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "*",
              "status": "unaffected",
              "version": "7.3-rc1",
              "versionType": "original_commit_for_fix"
            }
          ]
        }
      ],
      "cpeApplicability": [
        {
          "nodes": [
            {
              "cpeMatch": [
                {
                  "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                  "versionEndExcluding": "7.2.6",
                  "versionStartIncluding": "7.1",
                  "vulnerable": true
                },
                {
                  "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                  "versionEndExcluding": "7.3-rc1",
                  "versionStartIncluding": "7.1",
                  "vulnerable": true
                }
              ],
              "negate": false,
              "operator": "OR"
            }
          ]
        }
      ],
      "descriptions": [
        {
          "lang": "en",
          "value": "In the Linux kernel, the following vulnerability has been resolved:\n\narm64: entry: Avoid unnecessary local_irq_disable() on kernel exit\n\nCurrently, when exiting to kernel mode, we attempt involuntary\npreemption. The preemption logic expects IRQs to be disabled, which is\nwhy we call local_irq_disable() before attempting preemption.\n\nHowever, depending on the context, local_irq_disable() may be\nunnecessary:\n\n- __el1_irq(), the non-NMI EL1 IRQ path, already has IRQs disabled, so\n  local_irq_disable() is redundant.\n\n- irqentry_exit_to_kernel_mode_preempt() immediately returns when\n  exiting from an NMI-like context, so calling local_irq_disable()\n  beforehand is unnecessary work.\n\nFurthermore, it confuses the pNMI state tracking when we are in a\ncontext with interrupts disabled and the GIC_PRIO_PSR_I_SET bit is set\nin the PMR, leading to a warning when\nCONFIG_ARM64_DEBUG_PRIORITY_MASKING=y:\n\n     WARNING: ./arch/arm64/include/asm/irqflags.h:63 at arm64_exit_to_kernel_mode+0xb8/0xc0, CPU#40: retsnoop/31805\n     CPU: 40 UID: 0 PID: 31805 Comm: retsnoop Not tainted 7.2.0-rc6-next-20260805 #7 PREEMPTLAZY\n     pstate: 234013c9 (nzCv DAIF +PAN -UAO +TCO +DIT +SSBS BTYPE=--)\n     pc : arm64_exit_to_kernel_mode (arch/arm64/kernel/entry-common.c:63)\n     lr : el1_abort (arch/arm64/kernel/entry-common.c:323)\n     pmr: 000000f0\n     Call trace:\n      arm64_exit_to_kernel_mode (arch/arm64/kernel/entry-common.c:63) (P)\n      el1_abort (arch/arm64/kernel/entry-common.c:323)\n      el1h_64_sync_handler (arch/arm64/kernel/entry-common.c:449)\n      el1h_64_sync (arch/arm64/kernel/entry.S:589)\n      [...]\n\nSplit arm64_exit_to_kernel_mode() into preempt, non-preempt, and\ndispatch parts so that we can avoid this extra work where it is not\nneeded and avoid breaking the pNMI tracking logic."
        }
      ],
      "providerMetadata": {
        "dateUpdated": "2026-09-24T15:51:40.955Z",
        "orgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
        "shortName": "Linux"
      },
      "references": [
        {
          "url": "https://git.kernel.org/stable/c/49a61174186bed25d439ff37400c7ce5e3603e73"
        },
        {
          "url": "https://git.kernel.org/stable/c/39aebe0e89469c2904e60b1e977e0d4dbf33326b"
        }
      ],
      "title": "arm64: entry: Avoid unnecessary local_irq_disable() on kernel exit",
      "x_generator": {
        "engine": "bippy-1.2.0"
      }
    }
  },
  "cveMetadata": {
    "assignerOrgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
    "assignerShortName": "Linux",
    "cveId": "CVE-2026-93254",
    "datePublished": "2026-09-24T15:51:40.955Z",
    "dateReserved": "2026-09-17T16:02:15.096Z",
    "dateUpdated": "2026-09-24T15:51:40.955Z",
    "state": "PUBLISHED"
  },
  "dataType": "CVE_RECORD",
  "dataVersion": "5.2"
}

Sightings

Author	Source	Type	Date	Other

Nomenclature

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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.

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The approach is described in our paper Mapping CVEs to MITRE ATT&CK Techniques: A Curated Gold-Set Classifier and the Limits of LLM-Assisted Label Expansion.
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FKIE_CVE-2026-93254

CVE-2026-93254 (GCVE-0-2026-93254)

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