{"id":"CVE-2026-93795","title":"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","summary":"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 …","severity":"none","vendor":"Linux","product":"Linux","affected":["Linux >= 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 < 6e85f02d45b5977c0326a8d854c6db878aa6b34a","Linux >= 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 < 4c0d150fb98ea40760611979f4e664c244b20966","Linux >= 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 < dbbca20764382b4d411ec2918f4e278ffe547acc","Linux < 6.12.111","Linux < 6.18.53","Linux (all versions)"],"published":"2026-09-24","updated":"2026-09-24","sourceUpdated":"2026-09-24T17:17:12.270","source":"NVD","sourceUrl":"https://nvd.nist.gov/vuln/detail/CVE-2026-93795","references":[{"url":"https://git.kernel.org/stable/c/4c0d150fb98ea40760611979f4e664c244b20966","label":"416baaa9-dc9f-4396-8d5f-8c081fb06d67"},{"url":"https://git.kernel.org/stable/c/6e85f02d45b5977c0326a8d854c6db878aa6b34a","label":"416baaa9-dc9f-4396-8d5f-8c081fb06d67"},{"url":"https://git.kernel.org/stable/c/dbbca20764382b4d411ec2918f4e278ffe547acc","label":"416baaa9-dc9f-4396-8d5f-8c081fb06d67"}],"tags":["nvd","cve.org"],"ingestedAt":"2026-09-24T16:47:15.900Z","slug":"CVE-2026-93795","body":"## Overview\n\nIn 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().\n\n## Remediation\n\nRefer to the linked advisories for vendor-supplied fixes and affected version ranges.","depth":"sunlit","depthScore":3,"depthScoreParts":{"impact":2.8,"likelihood":0,"exploitation":0,"ransomware":0},"changes":[]}