{"id":"CVE-2026-46274","summary":"io-wq: check that the predecessor is hashed in io_wq_remove_pending()","details":"In the Linux kernel, the following vulnerability has been resolved:\n\nio-wq: check that the predecessor is hashed in io_wq_remove_pending()\n\nio_wq_remove_pending() needs to fix up wq-\u003ehash_tail[] if the cancelled\nwork was the tail of its hash bucket. When doing this, it checks whether\nthe preceding entry in acct-\u003ework_list has the same hash value, but\nnever checks that the predecessor is hashed at all. io_get_work_hash()\nis simply atomic_read(&work-\u003eflags) \u003e\u003e IO_WQ_HASH_SHIFT, and the hash\nbits are never set for non-hashed work, so it returns 0. Thus, when a\nhashed bucket-0 work is cancelled while a non-hashed work is its list\npredecessor, the check spuriously passes and a pointer to the non-hashed\nio_kiocb is stored in wq-\u003ehash_tail[0].\n\nBecause non-hashed work is dequeued via the fast path in\nio_get_next_work(), which never touches hash_tail[], the stale pointer\nis never cleared. Therefore, after the non-hashed io_kiocb completes and\nis freed back to req_cachep, wq-\u003ehash_tail[0] is a dangling pointer. The\nio_wq is per-task (tctx-\u003eio_wq) and survives ring open/close, so the\ndangling pointer persists for the lifetime of the task; the next hashed\nbucket-0 enqueue dereferences it in io_wq_insert_work() and\nwq_list_add_after() writes through freed memory.\n\nAdd the missing io_wq_is_hashed() check so a non-hashed predecessor\nnever inherits a hash_tail[] slot.","modified":"2026-10-28T02:30:36.611879459Z","published":"2026-06-08T14:30:53.323Z","related":["SUSE-SU-2026:22521-1","SUSE-SU-2026:22522-1","SUSE-SU-2026:22665-1","SUSE-SU-2026:22666-1","SUSE-SU-2026:23066-1","SUSE-SU-2026:23068-1","SUSE-SU-2026:23221-1","SUSE-SU-2026:23231-1","SUSE-SU-2026:23237-1","SUSE-SU-2026:23263-1","SUSE-SU-2026:23264-1","SUSE-SU-2026:23265-1","SUSE-SU-2026:23266-1","SUSE-SU-2026:23267-1","SUSE-SU-2026:23268-1","SUSE-SU-2026:23269-1","SUSE-SU-2026:23270-1","SUSE-SU-2026:23271-1","SUSE-SU-2026:23272-1","SUSE-SU-2026:23284-1","SUSE-SU-2026:23285-1","SUSE-SU-2026:23286-1","SUSE-SU-2026:23287-1","SUSE-SU-2026:23288-1","SUSE-SU-2026:23290-1","SUSE-SU-2026:23291-1","SUSE-SU-2026:23292-1","SUSE-SU-2026:23293-1","SUSE-SU-2026:23296-1","SUSE-SU-2026:23333-1","SUSE-SU-2026:23334-1","SUSE-SU-2026:23335-1","SUSE-SU-2026:23336-1","SUSE-SU-2026:23337-1","SUSE-SU-2026:23338-1","SUSE-SU-2026:23339-1","SUSE-SU-2026:23340-1","SUSE-SU-2026:23341-1","SUSE-SU-2026:23343-1","SUSE-SU-2026:23366-1","SUSE-SU-2026:23367-1","SUSE-SU-2026:23368-1","SUSE-SU-2026:23369-1","SUSE-SU-2026:23370-1","SUSE-SU-2026:23371-1","SUSE-SU-2026:23372-1","SUSE-SU-2026:23373-1","SUSE-SU-2026:23374-1","SUSE-SU-2026:23375-1","SUSE-SU-2026:23376-1","SUSE-SU-2026:23383-1","SUSE-SU-2026:23384-1","SUSE-SU-2026:23385-1","SUSE-SU-2026:23386-1","SUSE-SU-2026:23387-1","SUSE-SU-2026:23388-1","SUSE-SU-2026:23389-1","SUSE-SU-2026:23390-1","SUSE-SU-2026:23416-1","SUSE-SU-2026:23417-1","SUSE-SU-2026:23418-1","SUSE-SU-2026:23419-1","SUSE-SU-2026:23420-1","SUSE-SU-2026:23421-1","SUSE-SU-2026:23422-1","SUSE-SU-2026:23423-1","SUSE-SU-2026:23424-1","SUSE-SU-2026:23425-1","SUSE-SU-2026:23426-1","SUSE-SU-2026:23427-1","SUSE-SU-2026:23428-1","SUSE-SU-2026:23429-1","SUSE-SU-2026:23430-1","SUSE-SU-2026:23431-1","SUSE-SU-2026:23432-1","SUSE-SU-2026:23433-1","SUSE-SU-2026:23434-1","SUSE-SU-2026:23482-1","SUSE-SU-2026:23541-1","SUSE-SU-2026:2799-1","SUSE-SU-2026:2800-1","SUSE-SU-2026:2840-1","SUSE-SU-2026:2841-1","SUSE-SU-2026:3044-1","SUSE-SU-2026:3089-1","SUSE-SU-2026:3156-1","SUSE-SU-2026:3689-1","SUSE-SU-2026:3696-1","SUSE-SU-2026:3697-1","SUSE-SU-2026:3698-1","SUSE-SU-2026:3702-1","SUSE-SU-2026:3703-1","SUSE-SU-2026:3704-1","SUSE-SU-2026:3707-1","SUSE-SU-2026:3708-1","SUSE-SU-2026:3709-1","SUSE-SU-2026:3710-1","SUSE-SU-2026:3719-1","SUSE-SU-2026:3722-1","SUSE-SU-2026:3724-1","SUSE-SU-2026:3726-1","SUSE-SU-2026:3728-1","SUSE-SU-2026:3739-1","SUSE-SU-2026:3744-1","SUSE-SU-2026:3746-1","SUSE-SU-2026:3748-1","SUSE-SU-2026:3750-1","SUSE-SU-2026:3754-1","SUSE-SU-2026:3756-1","SUSE-SU-2026:3761-1","SUSE-SU-2026:3766-1","SUSE-SU-2026:3768-1","SUSE-SU-2026:3770-1","SUSE-SU-2026:3771-1","openSUSE-SU-2026:11014-1","openSUSE-SU-2026:21555-1"],"database_specific":{"cna_assigner":"Linux","osv_generated_from":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/46xxx/CVE-2026-46274.json"},"references":[{"type":"WEB","url":"https://git.kernel.org/stable/c/252c5051dba9c709b6a72f2866f93e5e618b3f06"},{"type":"WEB","url":"https://git.kernel.org/stable/c/5a20ebf0c81b61f5ea3b1b529c100cad69b9f603"},{"type":"WEB","url":"https://git.kernel.org/stable/c/d376c131af7c7739a87ff037ed2fdb67c2542c8a"},{"type":"WEB","url":"https://git.kernel.org/stable/c/d6a2d7b04b5a093021a7a0e2e69e9d5237dfa8cc"},{"type":"WEB","url":"https://git.kernel.org/stable/c/d6bda9df0c0a3080804181464d5c0f4d78a4e769"},{"type":"ADVISORY","url":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/46xxx/CVE-2026-46274.json"},{"type":"ADVISORY","url":"https://nvd.nist.gov/vuln/detail/CVE-2026-46274"},{"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":"204361a77f4018627addd4a06877448f088ddfc0"},{"fixed":"d6bda9df0c0a3080804181464d5c0f4d78a4e769"},{"fixed":"5a20ebf0c81b61f5ea3b1b529c100cad69b9f603"},{"fixed":"252c5051dba9c709b6a72f2866f93e5e618b3f06"},{"fixed":"d376c131af7c7739a87ff037ed2fdb67c2542c8a"},{"fixed":"d6a2d7b04b5a093021a7a0e2e69e9d5237dfa8cc"}]},{"type":"GIT","repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","events":[{"introduced":"5.8.6"},{"fixed":"5.9"}]},{"type":"GIT","repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","events":[{"introduced":"13f35a2c0fd5c6a4fcd8903542b053bcc914fcf5"}]}],"versions":["v5.8.18","v5.8.17","v5.8.16","v5.8.15","v5.8.14","v5.8.13","v5.8.12","v5.8.11","v5.8.10","v5.8.9","v5.8.8","v5.8.7","v5.8.6"],"database_specific":{"source":"https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2026-46274.json"}},{"package":{"name":"Kernel","ecosystem":"Linux"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"5.9.0"},{"fixed":"6.6.141"}]},{"type":"ECOSYSTEM","events":[{"introduced":"6.7.0"},{"fixed":"6.12.91"}]},{"type":"ECOSYSTEM","events":[{"introduced":"6.13.0"},{"fixed":"6.18.33"}]},{"type":"ECOSYSTEM","events":[{"introduced"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