{"id":"CVE-2026-93795","summary":"blk-cgroup: fix leaks and online flag on radix_tree_insert failure","details":"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-\u003eonline 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().","modified":"2026-09-26T03:48:26.829488838Z","published":"2026-09-24T16:02:28.654Z","database_specific":{"cna_assigner":"Linux","osv_generated_from":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/93xxx/CVE-2026-93795.json"},"references":[{"type":"WEB","url":"https://git.kernel.org/stable/c/4c0d150fb98ea40760611979f4e664c244b20966"},{"type":"WEB","url":"https://git.kernel.org/stable/c/6e85f02d45b5977c0326a8d854c6db878aa6b34a"},{"type":"WEB","url":"https://git.kernel.org/stable/c/dbbca20764382b4d411ec2918f4e278ffe547acc"},{"type":"ADVISORY","url":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/93xxx/CVE-2026-93795.json"},{"type":"ADVISORY","url":"https://nvd.nist.gov/vuln/detail/CVE-2026-93795"},{"type":"PACKAGE","url":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git"}],"affected":[{"ranges":[{"type":"GIT","repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","events":[{"introduced":"7fcf2b033b84e261dca283bc2911aaea4b07b525"},{"fixed":"6e85f02d45b5977c0326a8d854c6db878aa6b34a"},{"fixed":"4c0d150fb98ea40760611979f4e664c244b20966"},{"fixed":"dbbca20764382b4d411ec2918f4e278ffe547acc"}]}],"database_specific":{"source":"https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2026-93795.json"}},{"package":{"name":"Kernel","ecosystem":"Linux"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"5.0.0"},{"fixed":"6.12.111"}]},{"type":"ECOSYSTEM","events":[{"introduced":"6.13.0"},{"fixed":"6.18.53"}]}],"database_specific":{"source":"https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2026-93795.json"}}],"schema_version":"1.9.0"}