{"api_version":"1","generated_at":"2026-09-25T07:54:39+00:00","cve":"CVE-2026-93795","urls":{"html":"https://cve.report/CVE-2026-93795","api":"https://cve.report/api/cve/CVE-2026-93795.json","docs":"https://cve.report/api","cve_org":"https://www.cve.org/CVERecord?id=CVE-2026-93795","nvd":"https://nvd.nist.gov/vuln/detail/CVE-2026-93795"},"summary":{"title":"blk-cgroup: fix leaks and online flag on radix_tree_insert failure","description":"In the Linux kernel, the following vulnerability has been resolved:\n\nblk-cgroup: fix leaks and online flag on radix_tree_insert failure\n\nWhen radix_tree_insert() fails in blkg_create(), the error path has two\nissues:\n\n1. blkg->online is set to true unconditionally, even when the blkg was\n   never fully inserted.  Move the assignment inside the success block.\n\n2. The error path calls blkg_put() without first calling\n   percpu_ref_kill().  Because the refcount is still in percpu mode,\n   percpu_ref_put() only does this_cpu_sub() without checking for zero,\n   so blkg_release() is never triggered.  This permanently leaks the\n   blkg memory, its percpu iostat, policy data, the parent blkg\n   reference, and the cgroup css reference — the latter preventing the\n   cgroup from ever being destroyed.\n\nFix by replacing blkg_put() with percpu_ref_kill(), matching the pattern\nused in blkg_destroy().","state":"PUBLISHED","assigner":"Linux","published_at":"2026-09-24 17:17:12","updated_at":"2026-09-24 17:17:12"},"problem_types":[],"metrics":[],"references":[{"url":"https://git.kernel.org/stable/c/dbbca20764382b4d411ec2918f4e278ffe547acc","name":"https://git.kernel.org/stable/c/dbbca20764382b4d411ec2918f4e278ffe547acc","refsource":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","tags":[],"title":"","mime":"","httpstatus":"","archivestatus":"0"},{"url":"https://git.kernel.org/stable/c/4c0d150fb98ea40760611979f4e664c244b20966","name":"https://git.kernel.org/stable/c/4c0d150fb98ea40760611979f4e664c244b20966","refsource":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","tags":[],"title":"","mime":"","httpstatus":"","archivestatus":"0"},{"url":"https://git.kernel.org/stable/c/6e85f02d45b5977c0326a8d854c6db878aa6b34a","name":"https://git.kernel.org/stable/c/6e85f02d45b5977c0326a8d854c6db878aa6b34a","refsource":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","tags":[],"title":"","mime":"","httpstatus":"","archivestatus":"0"},{"url":"https://www.cve.org/CVERecord?id=CVE-2026-93795","name":"CVE Program record","refsource":"CVE.ORG","tags":["canonical"]},{"url":"https://nvd.nist.gov/vuln/detail/CVE-2026-93795","name":"NVD vulnerability detail","refsource":"NVD","tags":["canonical","analysis"]}],"affected":[{"source":"CNA","vendor":"Linux","product":"Linux","version":"affected 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 6e85f02d45b5977c0326a8d854c6db878aa6b34a git","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"affected 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 4c0d150fb98ea40760611979f4e664c244b20966 git","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"affected 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 dbbca20764382b4d411ec2918f4e278ffe547acc git","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"affected 6.12.111 semver","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"affected 6.18.53 semver","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"unaffected 6.12.111 6.12.* semver","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"unaffected 6.18.53 6.18.* semver","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"unaffected 7.2 * original_commit_for_fix","platforms":[]}],"timeline":[],"solutions":[],"workarounds":[],"exploits":[],"credits":[],"nvd_cpes":[],"vendor_comments":[],"enrichments":{"kev":null,"epss":null,"legacy_qids":[]},"source_records":{"cve_program":{"containers":{"cna":{"affected":[{"defaultStatus":"unaffected","product":"Linux","programFiles":["block/blk-cgroup.c"],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","vendor":"Linux","versions":[{"lessThan":"6e85f02d45b5977c0326a8d854c6db878aa6b34a","status":"affected","version":"1da177e4c3f41524e886b7f1b8a0c1fc7321cac2","versionType":"git"},{"lessThan":"4c0d150fb98ea40760611979f4e664c244b20966","status":"affected","version":"1da177e4c3f41524e886b7f1b8a0c1fc7321cac2","versionType":"git"},{"lessThan":"dbbca20764382b4d411ec2918f4e278ffe547acc","status":"affected","version":"1da177e4c3f41524e886b7f1b8a0c1fc7321cac2","versionType":"git"},{"lessThan":"6.12.111","status":"affected","version":"0","versionType":"semver"},{"lessThan":"6.18.53","status":"affected","version":"0","versionType":"semver"}]},{"defaultStatus":"affected","product":"Linux","programFiles":["block/blk-cgroup.c"],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","vendor":"Linux","versions":[{"lessThanOrEqual":"6.12.*","status":"unaffected","version":"6.12.111","versionType":"semver"},{"lessThanOrEqual":"6.18.*","status":"unaffected","version":"6.18.53","versionType":"semver"},{"lessThanOrEqual":"*","status":"unaffected","version":"7.2","versionType":"original_commit_for_fix"}]}],"cpeApplicability":[{"nodes":[{"cpeMatch":[{"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionEndExcluding":"6.12.111","vulnerable":true},{"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionEndExcluding":"6.18.53","vulnerable":true},{"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionEndExcluding":"7.2","vulnerable":true}],"negate":false,"operator":"OR"}]}],"descriptions":[{"lang":"en","value":"In the Linux kernel, the following vulnerability has been resolved:\n\nblk-cgroup: fix leaks and online flag on radix_tree_insert failure\n\nWhen radix_tree_insert() fails in blkg_create(), the error path has two\nissues:\n\n1. blkg->online is set to true unconditionally, even when the blkg was\n   never fully inserted.  Move the assignment inside the success block.\n\n2. The error path calls blkg_put() without first calling\n   percpu_ref_kill().  Because the refcount is still in percpu mode,\n   percpu_ref_put() only does this_cpu_sub() without checking for zero,\n   so blkg_release() is never triggered.  This permanently leaks the\n   blkg memory, its percpu iostat, policy data, the parent blkg\n   reference, and the cgroup css reference — the latter preventing the\n   cgroup from ever being destroyed.\n\nFix by replacing blkg_put() with percpu_ref_kill(), matching the pattern\nused in blkg_destroy()."}],"providerMetadata":{"dateUpdated":"2026-09-24T16:02:28.654Z","orgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","shortName":"Linux"},"references":[{"url":"https://git.kernel.org/stable/c/6e85f02d45b5977c0326a8d854c6db878aa6b34a"},{"url":"https://git.kernel.org/stable/c/4c0d150fb98ea40760611979f4e664c244b20966"},{"url":"https://git.kernel.org/stable/c/dbbca20764382b4d411ec2918f4e278ffe547acc"}],"title":"blk-cgroup: fix leaks and online flag on radix_tree_insert failure","x_generator":{"engine":"bippy-1.2.0"}}},"cveMetadata":{"assignerOrgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","assignerShortName":"Linux","cveId":"CVE-2026-93795","datePublished":"2026-09-24T16:02:28.654Z","dateReserved":"2026-09-18T17:59:28.789Z","dateUpdated":"2026-09-24T16:02:28.654Z","state":"PUBLISHED"},"dataType":"CVE_RECORD","dataVersion":"5.2"},"nvd":{"publishedDate":"2026-09-24 17:17:12","lastModifiedDate":"2026-09-24 17:17:12","problem_types":[],"metrics":[],"configurations":[]},"legacy_mitre":{"record":{"CveYear":"2026","CveId":"93795","Ordinal":"1","Title":"blk-cgroup: fix leaks and online flag on radix_tree_insert failu","CVE":"CVE-2026-93795","Year":"2026"},"notes":[{"CveYear":"2026","CveId":"93795","Ordinal":"1","NoteData":"In the Linux kernel, the following vulnerability has been resolved:\n\nblk-cgroup: fix leaks and online flag on radix_tree_insert failure\n\nWhen radix_tree_insert() fails in blkg_create(), the error path has two\nissues:\n\n1. blkg->online is set to true unconditionally, even when the blkg was\n   never fully inserted.  Move the assignment inside the success block.\n\n2. The error path calls blkg_put() without first calling\n   percpu_ref_kill().  Because the refcount is still in percpu mode,\n   percpu_ref_put() only does this_cpu_sub() without checking for zero,\n   so blkg_release() is never triggered.  This permanently leaks the\n   blkg memory, its percpu iostat, policy data, the parent blkg\n   reference, and the cgroup css reference — the latter preventing the\n   cgroup from ever being destroyed.\n\nFix by replacing blkg_put() with percpu_ref_kill(), matching the pattern\nused in blkg_destroy().","Type":"Description","Title":"blk-cgroup: fix leaks and online flag on radix_tree_insert failu"}]}}}