{"id":"CVE-2026-31598","summary":"ocfs2: fix possible deadlock between unlink and dio_end_io_write","details":"In the Linux kernel, the following vulnerability has been resolved:\n\nocfs2: fix possible deadlock between unlink and dio_end_io_write\n\nocfs2_unlink takes orphan dir inode_lock first and then ip_alloc_sem,\nwhile in ocfs2_dio_end_io_write, it acquires these locks in reverse order.\nThis creates an ABBA lock ordering violation on lock classes\nocfs2_sysfile_lock_key[ORPHAN_DIR_SYSTEM_INODE] and\nocfs2_file_ip_alloc_sem_key.\n\nLock Chain #0 (orphan dir inode_lock -\u003e ip_alloc_sem):\nocfs2_unlink\n  ocfs2_prepare_orphan_dir\n    ocfs2_lookup_lock_orphan_dir\n      inode_lock(orphan_dir_inode) \u003c- lock A\n    __ocfs2_prepare_orphan_dir\n      ocfs2_prepare_dir_for_insert\n        ocfs2_extend_dir\n\t  ocfs2_expand_inline_dir\n\t    down_write(&oi-\u003eip_alloc_sem) \u003c- Lock B\n\nLock Chain #1 (ip_alloc_sem -\u003e orphan dir inode_lock):\nocfs2_dio_end_io_write\n  down_write(&oi-\u003eip_alloc_sem) \u003c- Lock B\n  ocfs2_del_inode_from_orphan()\n    inode_lock(orphan_dir_inode) \u003c- Lock A\n\nDeadlock Scenario:\n  CPU0 (unlink)                     CPU1 (dio_end_io_write)\n  ------                            ------\n  inode_lock(orphan_dir_inode)\n                                    down_write(ip_alloc_sem)\n  down_write(ip_alloc_sem)\n                                    inode_lock(orphan_dir_inode)\n\nSince ip_alloc_sem is to protect allocation changes, which is unrelated\nwith operations in ocfs2_del_inode_from_orphan.  So move\nocfs2_del_inode_from_orphan out of ip_alloc_sem to fix the deadlock.","modified":"2026-06-18T03:55:07.262389072Z","published":"2026-04-24T14:42:23.304Z","related":["CGA-25vm-vh6v-c2pf","openSUSE-SU-2026:10703-1"],"database_specific":{"cna_assigner":"Linux","osv_generated_from":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/31xxx/CVE-2026-31598.json"},"references":[{"type":"WEB","url":"https://git.kernel.org/stable/c/297d8d7bb6a2bf133d3a3636edbdf94101cbd719"},{"type":"WEB","url":"https://git.kernel.org/stable/c/2b884d52273c60c298bd570163e8053657bbaff6"},{"type":"WEB","url":"https://git.kernel.org/stable/c/32630dee18c6bb2175c8a865a474749492eaf19c"},{"type":"WEB","url":"https://git.kernel.org/stable/c/4b80b5a838a32437f2cae0662578bac216a2c51a"},{"type":"WEB","url":"https://git.kernel.org/stable/c/93f35419eb84d58820040642cb6e7528fe4aba7a"},{"type":"WEB","url":"https://git.kernel.org/stable/c/b02da26a992db0c0e2559acbda0fc48d4a2fd337"},{"type":"WEB","url":"https://git.kernel.org/stable/c/bc0fb5c7d54c78be43a536df0e20dee32adb27d3"},{"type":"WEB","url":"https://git.kernel.org/stable/c/e049f7a9bd80b7319590789ea5e1c523d6339d91"},{"type":"WEB","url":"https://git.kernel.org/stable/c/f9fb1a7b635849322e1d7b7b6b26389778ec8e82"},{"type":"ADVISORY","url":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/31xxx/CVE-2026-31598.json"},{"type":"ADVISORY","url":"https://nvd.nist.gov/vuln/detail/CVE-2026-31598"},{"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":"a86a72a4a4e0ec109a98e2737948864ed6794bf7"},{"fixed":"297d8d7bb6a2bf133d3a3636edbdf94101cbd719"},{"fixed":"32630dee18c6bb2175c8a865a474749492eaf19c"},{"fixed":"93f35419eb84d58820040642cb6e7528fe4aba7a"},{"fixed":"4b80b5a838a32437f2cae0662578bac216a2c51a"},{"fixed":"2b884d52273c60c298bd570163e8053657bbaff6"},{"fixed":"bc0fb5c7d54c78be43a536df0e20dee32adb27d3"},{"fixed":"f9fb1a7b635849322e1d7b7b6b26389778ec8e82"},{"fixed":"e049f7a9bd80b7319590789ea5e1c523d6339d91"},{"fixed":"b02da26a992db0c0e2559acbda0fc48d4a2fd337"}]}],"database_specific":{"source":"https://storage.googleapis.com/osv-test-cve-osv-conversion/osv-output/CVE-2026-31598.json"}},{"package":{"name":"Kernel","ecosystem":"Linux"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"4.6.0"},{"fixed":"5.10.258"}]},{"type":"ECOSYSTEM","events":[{"introduced":"5.11.0"},{"fixed":"5.15.209"}]},{"type":"ECOSYSTEM","events":[{"introduced":"5.16.0"},{"fixed":"6.1.175"}]},{"type":"ECOSYSTEM","events":[{"introduced":"6.2.0"},{"fixed":"6.6.136"}]},{"type":"ECOSYSTEM","events":[{"introduced":"6.7.0"},{"fixed":"6.12.83"}]},{"type":"ECOSYSTEM","events":[{"introduced":"6.13.0"},{"fixed":"6.18.24"}]},{"type":"ECOSYSTEM","events":[{"introduced":"6.19.0"},{"fixed":"6.19.14"}]},{"type":"ECOSYSTEM","events":[{"introduced":"6.20.0"},{"fixed":"7.0.1"}]}],"database_specific":{"source":"https://storage.googleapis.com/osv-test-cve-osv-conversion/osv-output/CVE-2026-31598.json"}}],"schema_version":"1.7.5","severity":[{"type":"CVSS_V3","score":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H"}]}