{"id":"CVE-2026-98972","state":"PUBLISHED","title":"cgroup/cpuset: Don't access cpuset_cgrp_subsys.root in is_in_v2_mode()","description":"In the Linux kernel, the following vulnerability has been resolved:\n\ncgroup/cpuset: Don't access cpuset_cgrp_subsys.root in is_in_v2_mode()\n\nAfter seeing the patch [1] to guard is_in_v2_mode() with RCU, it makes\nme realize that is_in_v2_mode() may be called in a context where a new\ncgroup filesystem is being rebound with stale cpuset_cgrp_subsys.root\npointer. Avoid this potential UaF situation by adding a new cpuset_v2_mode\nflag which is set when the cpuset_v2_mode mount option is used. This\nflag is written into only when cpuset_bind() is being called with a\nstable cpuset_cgrp_subsys.root value. The is_in_v2_mode() helper is\nmodified to read the new cpuset_v2_mode flag instead of accessing\ncpuset_cgrp_subsys.root directly.\n\n[1] https://lore.kernel.org/lkml/20260929084124.626693-2-arighi@nvidia.com","publishedAt":"2026-10-23T12:19:45.458Z","updatedAt":"2026-10-23T12:19:45.458Z","severity":null,"assigner":"Linux","products":["Linux Linux"],"affected":[{"vendor":"Linux","product":"Linux","defaultStatus":"unaffected","versions":[{"version":"b8d1b8ee93df8ffbabbeadd65d39853cfad6d698","status":"affected","lessThan":"988bf67a13890a37a33201f95947095ca9bec856","versionType":"git"},{"version":"b8d1b8ee93df8ffbabbeadd65d39853cfad6d698","status":"affected","lessThan":"e06b678e3b4e12fdaa0b51a7a5a54abc5dbd6469","versionType":"git"}],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["kernel/cgroup/cpuset.c"]},{"vendor":"Linux","product":"Linux","defaultStatus":"affected","versions":[{"version":"4.14","status":"affected"},{"version":"0","status":"unaffected","lessThan":"4.14","versionType":"semver"},{"version":"7.2.11","status":"unaffected","lessThanOrEqual":"7.2.*","versionType":"semver"},{"version":"7.3","status":"unaffected","lessThanOrEqual":"*","versionType":"original_commit_for_fix"}],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["kernel/cgroup/cpuset.c"]}],"references":["https://git.kernel.org/stable/c/988bf67a13890a37a33201f95947095ca9bec856","https://git.kernel.org/stable/c/e06b678e3b4e12fdaa0b51a7a5a54abc5dbd6469"],"weaknesses":[],"ingestedAt":"2026-10-29T20:13:43.249Z","source":{"repository":"CVEProject/cvelistV5","path":"cves/2026/98xxx/CVE-2026-98972.json","commit":"556c9d3a8cd17e218bb8e452ba7cd619a384ff47"},"raw":{"dataType":"CVE_RECORD","dataVersion":"5.2","cveMetadata":{"cveId":"CVE-2026-98972","state":"PUBLISHED","datePublished":"2026-10-23T12:19:45.458Z","dateUpdated":"2026-10-23T12:19:45.458Z","assignerShortName":"Linux","assignerOrgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","dateReserved":"2026-09-25T10:25:14.383Z"},"containers":{"cna":{"title":"cgroup/cpuset: Don't access cpuset_cgrp_subsys.root in is_in_v2_mode()","descriptions":[{"lang":"en","value":"In the Linux kernel, the following vulnerability has been resolved:\n\ncgroup/cpuset: Don't access cpuset_cgrp_subsys.root in is_in_v2_mode()\n\nAfter seeing the patch [1] to guard is_in_v2_mode() with RCU, it makes\nme realize that is_in_v2_mode() may be called in a context where a new\ncgroup filesystem is being rebound with stale cpuset_cgrp_subsys.root\npointer. Avoid this potential UaF situation by adding a new cpuset_v2_mode\nflag which is set when the cpuset_v2_mode mount option is used. This\nflag is written into only when cpuset_bind() is being called with a\nstable cpuset_cgrp_subsys.root value. The is_in_v2_mode() helper is\nmodified to read the new cpuset_v2_mode flag instead of accessing\ncpuset_cgrp_subsys.root directly.\n\n[1] https://lore.kernel.org/lkml/20260929084124.626693-2-arighi@nvidia.com"}],"affected":[{"vendor":"Linux","product":"Linux","defaultStatus":"unaffected","versions":[{"version":"b8d1b8ee93df8ffbabbeadd65d39853cfad6d698","status":"affected","lessThan":"988bf67a13890a37a33201f95947095ca9bec856","versionType":"git"},{"version":"b8d1b8ee93df8ffbabbeadd65d39853cfad6d698","status":"affected","lessThan":"e06b678e3b4e12fdaa0b51a7a5a54abc5dbd6469","versionType":"git"}],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["kernel/cgroup/cpuset.c"]},{"vendor":"Linux","product":"Linux","defaultStatus":"affected","versions":[{"version":"4.14","status":"affected"},{"version":"0","status":"unaffected","lessThan":"4.14","versionType":"semver"},{"version":"7.2.11","status":"unaffected","lessThanOrEqual":"7.2.*","versionType":"semver"},{"version":"7.3","status":"unaffected","lessThanOrEqual":"*","versionType":"original_commit_for_fix"}],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["kernel/cgroup/cpuset.c"]}],"references":[{"url":"https://git.kernel.org/stable/c/988bf67a13890a37a33201f95947095ca9bec856"},{"url":"https://git.kernel.org/stable/c/e06b678e3b4e12fdaa0b51a7a5a54abc5dbd6469"}],"providerMetadata":{"shortName":"Linux","orgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","dateUpdated":"2026-10-23T12:19:45.458Z"},"cpeApplicability":[{"nodes":[{"operator":"OR","negate":false,"cpeMatch":[{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"4.14","versionEndExcluding":"7.2.11"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"4.14","versionEndExcluding":"7.3"}]}]}],"x_generator":{"engine":"bippy-1.2.0"}}}}}