{ "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": "2026-07-19T15:39:46.536Z" }, "containers": { "cna": { "providerMetadata": { "orgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "shortName": "Linux", "dateUpdated": "2026-07-19T15:39:46.536Z" }, "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: //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": "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": "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": "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/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" } } } }