{
    "dataType": "CVE_RECORD",
    "dataVersion": "5.2",
    "cveMetadata": {
        "cveId": "CVE-2026-64070",
        "assignerOrgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
        "state": "PUBLISHED",
        "assignerShortName": "Linux",
        "dateReserved": "2026-07-19T07:54:57.030Z",
        "datePublished": "2026-07-19T15:39:46.536Z",
        "dateUpdated": "2026-09-02T12:49:39.984Z"
    },
    "containers": {
        "cna": {
            "providerMetadata": {
                "orgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
                "shortName": "Linux",
                "dateUpdated": "2026-09-02T12:49:39.984Z"
            },
            "descriptions": [
                {
                    "lang": "en",
                    "value": "In the Linux kernel, the following vulnerability has been resolved:\n\npowerpc/hv-gpci: fix preempt count leak in sysfs show paths\n\nFour sysfs show() callbacks in hv-gpci take get_cpu_var(hv_gpci_reqb)\n(which calls preempt_disable()) but only call the matching put_cpu_var()\non the error path under the 'out:' label. Every successful read leaks\none preempt_disable():\n\n  processor_bus_topology_show()\n  processor_config_show()\n  affinity_domain_via_virtual_processor_show()\n  affinity_domain_via_domain_show()\n\n(affinity_domain_via_partition_show() was already correct.)\n\nOn a CONFIG_PREEMPT=y kernel, repeated reads raise preempt_count and\neventually return to userspace with preemption still disabled. The\nnext user-mode page fault then hits faulthandler_disabled() == 1,\ngets forced to SIGSEGV, and the resulting coredump trips\n'BUG: scheduling while atomic' in call_usermodehelper_exec ->\nwait_for_completion_state -> schedule:\n\n  BUG: scheduling while atomic: <task>/<pid>/0x00000004\n  ...\n  __schedule_bug+0x6c/0x90\n  __schedule+0x58c/0x13a0\n  schedule+0x48/0x1a0\n  schedule_timeout+0x104/0x170\n  wait_for_completion_state+0x16c/0x330\n  call_usermodehelper_exec+0x254/0x2d0\n  vfs_coredump+0x1050/0x2590\n  get_signal+0xb9c/0xc80\n  do_notify_resume+0xf8/0x470\n\nAdd an out_success label that calls put_cpu_var() before returning\nthe byte count, mirroring affinity_domain_via_partition_show()."
                }
            ],
            "affected": [
                {
                    "product": "Linux",
                    "vendor": "Linux",
                    "defaultStatus": "unaffected",
                    "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
                    "programFiles": [
                        "arch/powerpc/perf/hv-gpci.c"
                    ],
                    "versions": [
                        {
                            "version": "71f1c39647d8c9d4d54a861ec81f1ff17544bcb6",
                            "lessThan": "b300312562fd6e4729697adb9f777f00ca0429f3",
                            "status": "affected",
                            "versionType": "git"
                        },
                        {
                            "version": "71f1c39647d8c9d4d54a861ec81f1ff17544bcb6",
                            "lessThan": "45afabe7f99c5d8746434ee41c86584c01d70147",
                            "status": "affected",
                            "versionType": "git"
                        },
                        {
                            "version": "71f1c39647d8c9d4d54a861ec81f1ff17544bcb6",
                            "lessThan": "b61ebb2826ca1852c2bbd92a676fb622c358cab4",
                            "status": "affected",
                            "versionType": "git"
                        },
                        {
                            "version": "71f1c39647d8c9d4d54a861ec81f1ff17544bcb6",
                            "lessThan": "903409000a07ac8e31ffedeb8516f4f8d67150c8",
                            "status": "affected",
                            "versionType": "git"
                        },
                        {
                            "version": "71f1c39647d8c9d4d54a861ec81f1ff17544bcb6",
                            "lessThan": "dbc30a57bd8e026995e9fa8e8c31cffd18542c01",
                            "status": "affected",
                            "versionType": "git"
                        }
                    ]
                },
                {
                    "product": "Linux",
                    "vendor": "Linux",
                    "defaultStatus": "affected",
                    "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
                    "programFiles": [
                        "arch/powerpc/perf/hv-gpci.c"
                    ],
                    "versions": [
                        {
                            "version": "6.6",
                            "status": "affected"
                        },
                        {
                            "version": "0",
                            "lessThan": "6.6",
                            "status": "unaffected",
                            "versionType": "semver"
                        },
                        {
                            "version": "6.6.156",
                            "lessThanOrEqual": "6.6.*",
                            "status": "unaffected",
                            "versionType": "semver"
                        },
                        {
                            "version": "6.12.108",
                            "lessThanOrEqual": "6.12.*",
                            "status": "unaffected",
                            "versionType": "semver"
                        },
                        {
                            "version": "6.18.49",
                            "lessThanOrEqual": "6.18.*",
                            "status": "unaffected",
                            "versionType": "semver"
                        },
                        {
                            "version": "7.0.11",
                            "lessThanOrEqual": "7.0.*",
                            "status": "unaffected",
                            "versionType": "semver"
                        },
                        {
                            "version": "7.1",
                            "lessThanOrEqual": "*",
                            "status": "unaffected",
                            "versionType": "original_commit_for_fix"
                        }
                    ]
                }
            ],
            "cpeApplicability": [
                {
                    "nodes": [
                        {
                            "operator": "OR",
                            "negate": false,
                            "cpeMatch": [
                                {
                                    "vulnerable": true,
                                    "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                                    "versionStartIncluding": "6.6",
                                    "versionEndExcluding": "6.6.156"
                                },
                                {
                                    "vulnerable": true,
                                    "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                                    "versionStartIncluding": "6.6",
                                    "versionEndExcluding": "6.12.108"
                                },
                                {
                                    "vulnerable": true,
                                    "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                                    "versionStartIncluding": "6.6",
                                    "versionEndExcluding": "6.18.49"
                                },
                                {
                                    "vulnerable": true,
                                    "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                                    "versionStartIncluding": "6.6",
                                    "versionEndExcluding": "7.0.11"
                                },
                                {
                                    "vulnerable": true,
                                    "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                                    "versionStartIncluding": "6.6",
                                    "versionEndExcluding": "7.1"
                                }
                            ]
                        }
                    ]
                }
            ],
            "references": [
                {
                    "url": "https://git.kernel.org/stable/c/b300312562fd6e4729697adb9f777f00ca0429f3"
                },
                {
                    "url": "https://git.kernel.org/stable/c/45afabe7f99c5d8746434ee41c86584c01d70147"
                },
                {
                    "url": "https://git.kernel.org/stable/c/b61ebb2826ca1852c2bbd92a676fb622c358cab4"
                },
                {
                    "url": "https://git.kernel.org/stable/c/903409000a07ac8e31ffedeb8516f4f8d67150c8"
                },
                {
                    "url": "https://git.kernel.org/stable/c/dbc30a57bd8e026995e9fa8e8c31cffd18542c01"
                }
            ],
            "title": "powerpc/hv-gpci: fix preempt count leak in sysfs show paths",
            "x_generator": {
                "engine": "bippy-1.2.0"
            }
        }
    }
}