{"dataType": "CVE_RECORD", "dataVersion": "5.2", "cveMetadata": {"cveId": "CVE-2026-98542", "assignerOrgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "state": "PUBLISHED", "assignerShortName": "Linux", "dateReserved": "2026-09-25T10:25:14.356Z", "datePublished": "2026-10-18T15:18:10.035Z", "dateUpdated": "2026-10-18T15:18:10.035Z"}, "containers": {"cna": {"providerMetadata": {"orgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "shortName": "Linux", "dateUpdated": "2026-10-18T15:18:10.035Z"}, "descriptions": [{"lang": "en", "value": "In the Linux kernel, the following vulnerability has been resolved:\n\ncgroup/cpuset: Return PERR_NOCPUS in remote_partition_enable() on subpartitions_cpus conflict\n\nWhen a remote partition is created underneath an existing local partition\nvia a non-partition (PRS_MEMBER) intermediate cgroup, update_prstate() sees\nparent->partition_root_state == PRS_MEMBER and calls\nremote_partition_enable().\n\nCommit 86888c7bd117 (\"cgroup/cpuset: Add warnings to catch inconsistency\nin exclusive CPUs\") replaced the cpumask_intersects(tmp->new_cpus,\nsubpartitions_cpus) error check in remote_partition_enable() with\nWARN_ON_ONCE(). As a result, remote_partition_enable() emits a warning\nand proceeds to enable the remote partition on CPUs that are already\nowned by the ancestor local partition in subpartitions_cpus.\n\nThis can be reproduced on Linux 7.3.0-rc3 with:\n\n mkdir -p /tmp/cg1\n mount -t cgroup2 none /tmp/cg1\n echo \"+cpuset\" > /tmp/cg1/cgroup.subtree_control\n\n mkdir /tmp/cg1/A\n echo 1 > /tmp/cg1/A/cpuset.cpus\n echo 1 > /tmp/cg1/A/cpuset.cpus.exclusive\n echo root > /tmp/cg1/A/cpuset.cpus.partition\n echo \"+cpuset\" > /tmp/cg1/A/cgroup.subtree_control\n\n mkdir /tmp/cg1/A/B\n echo 1 > /tmp/cg1/A/B/cpuset.cpus\n echo 1 > /tmp/cg1/A/B/cpuset.cpus.exclusive\n echo \"+cpuset\" > /tmp/cg1/A/B/cgroup.subtree_control\n\n mkdir /tmp/cg1/A/B/D\n echo 1 > /tmp/cg1/A/B/D/cpuset.cpus\n echo 1 > /tmp/cg1/A/B/D/cpuset.cpus.exclusive\n echo root > /tmp/cg1/A/B/D/cpuset.cpus.partition\n\nwhich triggers:\n\n WARNING: kernel/cgroup/cpuset.c:1594 at remote_partition_enable+0x1c1/0x300\n\nand leaves both /tmp/cg1/A and /tmp/cg1/A/B/D as active root partitions\nclaiming exclusive CPU 1.\n\nFix this by returning PERR_NOCPUS when tmp->new_cpus intersects\nsubpartitions_cpus in remote_partition_enable(), matching the error code\nused by remote_cpus_update() for the same subpartitions_cpus conflict, and\nadd a regression test case to\ntools/testing/selftests/cgroup/test_cpuset_prs.sh.\n\nTested in QEMU on Linux 7.3.0-rc3 using the reproducer above and\ntools/testing/selftests/cgroup/test_cpuset_prs.sh."}], "affected": [{"product": "Linux", "vendor": "Linux", "defaultStatus": "unaffected", "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "programFiles": ["kernel/cgroup/cpuset.c", "tools/testing/selftests/cgroup/test_cpuset_prs.sh"], "versions": [{"version": "86888c7bd117c29eab169c37e5f6bbbf583da983", "lessThan": "241e67b60308cdce25bba66616a109759edd1d40", "status": "affected", "versionType": "git"}, {"version": "86888c7bd117c29eab169c37e5f6bbbf583da983", "lessThan": "0751ab665cb3dcdac224b002565f2e28461740d5", "status": "affected", "versionType": "git"}, {"version": "86888c7bd117c29eab169c37e5f6bbbf583da983", "lessThan": "31c88350b7dd1522792f726f79607f31bb55c50f", "status": "affected", "versionType": "git"}]}, {"product": "Linux", "vendor": "Linux", "defaultStatus": "affected", "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "programFiles": ["kernel/cgroup/cpuset.c", "tools/testing/selftests/cgroup/test_cpuset_prs.sh"], "versions": [{"version": "6.16", "status": "affected"}, {"version": "0", "lessThan": "6.16", "status": "unaffected", "versionType": "semver"}, {"version": "6.18.55", "lessThanOrEqual": "6.18.*", "status": "unaffected", "versionType": "semver"}, {"version": "7.2.9", "lessThanOrEqual": "7.2.*", "status": "unaffected", "versionType": "semver"}, {"version": "7.3-rc5", "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": "6.16", "versionEndExcluding": "6.18.55"}, {"vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "6.16", "versionEndExcluding": "7.2.9"}, {"vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "6.16", "versionEndExcluding": "7.3-rc5"}]}]}], "references": [{"url": "https://git.kernel.org/stable/c/241e67b60308cdce25bba66616a109759edd1d40"}, {"url": "https://git.kernel.org/stable/c/0751ab665cb3dcdac224b002565f2e28461740d5"}, {"url": "https://git.kernel.org/stable/c/31c88350b7dd1522792f726f79607f31bb55c50f"}], "title": "cgroup/cpuset: Return PERR_NOCPUS in remote_partition_enable() on subpartitions_cpus conflict", "x_generator": {"engine": "bippy-1.2.0"}}}}

{}

{"affected": [{"affectedData": [{"defaultStatus": "unaffected", "product": "Linux", "programFiles": ["kernel/cgroup/cpuset.c", "tools/testing/selftests/cgroup/test_cpuset_prs.sh"], "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "vendor": "Linux", "versions": [{"lessThan": "241e67b60308cdce25bba66616a109759edd1d40", "status": "affected", "version": "86888c7bd117c29eab169c37e5f6bbbf583da983", "versionType": "git"}, {"lessThan": "0751ab665cb3dcdac224b002565f2e28461740d5", "status": "affected", "version": "86888c7bd117c29eab169c37e5f6bbbf583da983", "versionType": "git"}, {"lessThan": "31c88350b7dd1522792f726f79607f31bb55c50f", "status": "affected", "version": "86888c7bd117c29eab169c37e5f6bbbf583da983", "versionType": "git"}]}, {"defaultStatus": "affected", "product": "Linux", "programFiles": ["kernel/cgroup/cpuset.c", "tools/testing/selftests/cgroup/test_cpuset_prs.sh"], "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": "6.18.55", "versionType": "semver"}, {"lessThanOrEqual": "7.2.*", "status": "unaffected", "version": "7.2.9", "versionType": "semver"}, {"lessThanOrEqual": "*", "status": "unaffected", "version": "7.3-rc5", "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\ncgroup/cpuset: Return PERR_NOCPUS in remote_partition_enable() on subpartitions_cpus conflict\n\nWhen a remote partition is created underneath an existing local partition\nvia a non-partition (PRS_MEMBER) intermediate cgroup, update_prstate() sees\nparent->partition_root_state == PRS_MEMBER and calls\nremote_partition_enable().\n\nCommit 86888c7bd117 (\"cgroup/cpuset: Add warnings to catch inconsistency\nin exclusive CPUs\") replaced the cpumask_intersects(tmp->new_cpus,\nsubpartitions_cpus) error check in remote_partition_enable() with\nWARN_ON_ONCE(). As a result, remote_partition_enable() emits a warning\nand proceeds to enable the remote partition on CPUs that are already\nowned by the ancestor local partition in subpartitions_cpus.\n\nThis can be reproduced on Linux 7.3.0-rc3 with:\n\n mkdir -p /tmp/cg1\n mount -t cgroup2 none /tmp/cg1\n echo \"+cpuset\" > /tmp/cg1/cgroup.subtree_control\n\n mkdir /tmp/cg1/A\n echo 1 > /tmp/cg1/A/cpuset.cpus\n echo 1 > /tmp/cg1/A/cpuset.cpus.exclusive\n echo root > /tmp/cg1/A/cpuset.cpus.partition\n echo \"+cpuset\" > /tmp/cg1/A/cgroup.subtree_control\n\n mkdir /tmp/cg1/A/B\n echo 1 > /tmp/cg1/A/B/cpuset.cpus\n echo 1 > /tmp/cg1/A/B/cpuset.cpus.exclusive\n echo \"+cpuset\" > /tmp/cg1/A/B/cgroup.subtree_control\n\n mkdir /tmp/cg1/A/B/D\n echo 1 > /tmp/cg1/A/B/D/cpuset.cpus\n echo 1 > /tmp/cg1/A/B/D/cpuset.cpus.exclusive\n echo root > /tmp/cg1/A/B/D/cpuset.cpus.partition\n\nwhich triggers:\n\n WARNING: kernel/cgroup/cpuset.c:1594 at remote_partition_enable+0x1c1/0x300\n\nand leaves both /tmp/cg1/A and /tmp/cg1/A/B/D as active root partitions\nclaiming exclusive CPU 1.\n\nFix this by returning PERR_NOCPUS when tmp->new_cpus intersects\nsubpartitions_cpus in remote_partition_enable(), matching the error code\nused by remote_cpus_update() for the same subpartitions_cpus conflict, and\nadd a regression test case to\ntools/testing/selftests/cgroup/test_cpuset_prs.sh.\n\nTested in QEMU on Linux 7.3.0-rc3 using the reproducer above and\ntools/testing/selftests/cgroup/test_cpuset_prs.sh."}], "id": "CVE-2026-98542", "lastModified": "2026-10-18T16:17:06.090", "metrics": {}, "published": "2026-10-18T16:17:06.090", "references": [{"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "url": "https://git.kernel.org/stable/c/0751ab665cb3dcdac224b002565f2e28461740d5"}, {"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "url": "https://git.kernel.org/stable/c/241e67b60308cdce25bba66616a109759edd1d40"}, {"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "url": "https://git.kernel.org/stable/c/31c88350b7dd1522792f726f79607f31bb55c50f"}], "sourceIdentifier": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "vulnStatus": "Received"}

{}

{"affected": [{"configurations": [{"platform": null, "status": "affected", "versions": {"scheme": "code_commit", "value": "[86888c7bd117c29eab169c37e5f6bbbf583da983,241e67b60308cdce25bba66616a109759edd1d40)"}}, {"platform": null, "status": "affected", "versions": {"scheme": "code_commit", "value": "[86888c7bd117c29eab169c37e5f6bbbf583da983,0751ab665cb3dcdac224b002565f2e28461740d5)"}}, {"platform": null, "status": "affected", "versions": {"scheme": "code_commit", "value": "[86888c7bd117c29eab169c37e5f6bbbf583da983,31c88350b7dd1522792f726f79607f31bb55c50f)"}}], "enrichment": {"confidence": 99.0, "confidence_source": "inferred", "scores": [{"score": 99.0, "source": "inferred"}, {"score": 100.0, "source": "matching"}]}, "original": {"product": "Linux", "source": "cna", "vendor": "Linux"}, "product": "linux_kernel", "vendor": "linux"}, {"configurations": [{"platform": null, "status": "affected", "versions": {"scheme": "generic", "value": "6.16"}}, {"platform": null, "status": "unaffected", "versions": {"scheme": "generic", "value": "[0,6.16)"}}, {"platform": null, "status": "unaffected", "versions": {"scheme": "generic", "value": "[6.18.55,6.19.0)"}}, {"platform": null, "status": "unaffected", "versions": {"scheme": "generic", "value": "[7.2.9,7.3.0)"}}, {"platform": null, "status": "unaffected", "versions": {"scheme": "generic", "value": "[7.3-rc5,*]"}}], "enrichment": {"confidence": 99.0, "confidence_source": "inferred", "scores": [{"score": 99.0, "source": "inferred"}, {"score": 100.0, "source": "matching"}]}, "original": {"product": "Linux", "source": "cna", "vendor": "Linux"}, "product": "linux_kernel", "vendor": "linux"}], "created": "2026-10-18T23:30:14.147212+00:00", "updated": "2026-10-19T03:15:14.427195+00:00", "vendors": ["linux", "linux$PRODUCT$linux_kernel"], "weaknesses": ["CWE-665"]}