{"answers":{"affected":"","exploited":"There is no known exploitation of CVE-2026-89491 in the wild and no public exploit code.","fix":"Apply the vendor's patch.","what":"CVE-2026-89491 is a denial of service vulnerability in Linux, published on 11 Sep 2026. It can only be exploited from the same machine or local network, with no action from the victim."},"fix_prompt":"Check this codebase for CVE-2026-89491 and fix it if it is affected.\n\nWhat it is: CVE-2026-89491 is a denial of service vulnerability in Linux, published on 11 Sep 2026. It can only be exploited from the same machine or local network, with no action from the victim.\nExploitation: There is no known exploitation of CVE-2026-89491 in the wild and no public exploit code.\n\nAffected product: Linux. No package-level version data is available, so check the vendor advisory linked from the reference page.\n\nTask:\n1. Search the dependency manifests and lockfiles (for example package.json, package-lock.json, requirements.txt, poetry.lock, uv.lock, pom.xml, build.gradle, go.mod, Cargo.lock, Gemfile.lock) and any Dockerfiles for the affected packages, including transitive dependencies.\n2. If an affected version is in use, upgrade it to the fixed version for its release line with the project's package manager, so the lockfile is regenerated. Prefer the smallest upgrade that fixes it.\n3. If there is no fix, or the upgrade would break the build, do not guess: explain the risk and the safest workaround instead.\n4. Run the tests and summarise what changed and why.\n5. If nothing in the project is affected, say so and change nothing.\n\nReference: https://insights.sbomify.com/CVE-2026-89491/ (Markdown: https://insights.sbomify.com/CVE-2026-89491/index.md)","id":"CVE-2026-89491","markdown":"https://insights.sbomify.com/CVE-2026-89491/index.md","name":"CVE-2026-89491","record":{"aliases":["AZL-100265","BELL-CVE-2026-89491","DEBIAN-CVE-2026-89491","GHSA-r32m-fj66-qf6p","UBUNTU-CVE-2026-89491"],"analysis":{"component_type":"kernel","fix_type":"patch","impacts":["denial_of_service"],"network_reachable":"adjacent_or_local","non_default_config":true,"product_category":"Linux kernel","requires_auth":"none","summary":"A local attacker can trigger a kernel bug or deadlock in the OCFS2 cluster module by mounting a filesystem, causing a denial of service.","user_interaction":"not_required","vuln_class":"denial_of_service"},"analysis_generated_by":"qwen3.8-flash-next","assigner":"Linux","cpe":[],"cvss":{"score":null,"severity":null,"source":null,"vector":null,"version":null},"cwes":[],"description":"In the Linux kernel, the following vulnerability has been resolved:\n\nocfs2: cluster: don't sleep while holding o2hb_live_lock in o2hb_region_pin()\n\nPatch series \"ocfs2: cluster: o2hb_region_pin() fixes\", v2.\n\nThis series fixes three related issues in o2hb_region_pin(), all are from\nthe original implementation in commit: 58a3158a5d17 (\"ocfs2/cluster:\nPin/unpin o2hb regions\"):\n\n1) It is called with o2hb_live_lock (a spinlock) held, but the\n   underlying configfs_depend_item() sleeps (takes inode rwsem and\n   pins the filesystem).  This triggers BUG under\n   CONFIG_DEBUG_ATOMIC_SLEEP.\n\n2) When called from the configfs drop_item callback, it creates a\n   lock order inversion: parent inode_lock -\u003e configfs root\n   inode_lock, which can deadlock against subsystem unregistration\n   paths taking root -\u003e parent.\n\n3) If pinning fails partway through o2hb_region_inc_user(), the\n   o2hb_dependent_users counter is leaked and partially-pinned\n   regions are never released, leaving heartbeat regions\n   unprotected on subsequent mounts.\n\nPatch 1 reworks o2hb_region_pin() to drop o2hb_live_lock across each\nsleeping configfs_depend_item() call, using a config_item reference to\nkeep the region alive while unlocked.\n\nPatch 2 adds a from_callback parameter to select\nconfigfs_depend_item_unlocked() when called from configfs context,\navoiding the inode_lock nesting.\n\nPatch 3 fixes the error path in o2hb_region_inc_user() to unpin and\ndecrement the counter on failure.\n\nThis patch (of 3):\n\no2hb_region_pin() is always called with the o2hb_live_lock spinlock held\n(from o2hb_region_inc_user() and o2hb_heartbeat_group_drop_item()), but it\ncalls o2nm_depend_item() -\u003e configfs_depend_item(), which sleeps: it pins\nthe configfs filesystem and takes the configfs root inode rwsem.  Under\nCONFIG_DEBUG_ATOMIC_SLEEP this triggers:\n\n  BUG: sleeping function called from invalid context at kernel/locking/rwsem.c\n  in_atomic(): 1, ... name: mount.ocfs2\n    down_write\n    configfs_depend_item\n    o2hb_region_pin\n    o2hb_region_inc_user\n    o2hb_register_callback\n    dlm_register_domain_handlers\n    ...\n    ocfs2_dlm_init\n    ocfs2_mount_volume\n    ocfs2_fill_super\n\nRework o2hb_region_pin() to pin one region at a time with the lock dropped\nacross the sleeping call: under o2hb_live_lock find the next eligible\nregion and take a config_item reference to keep it alive, drop the lock,\ncall o2nm_depend_item(), then retake the lock and record the pin.  The\nconfig_item_put() is done with the lock released as well, since\no2hb_region_release() also acquires o2hb_live_lock and can sleep.  The\nregion list may change while unlocked, so the scan restarts from the top\nafter each pin.  Local heartbeat still pins only the matching region;\nglobal heartbeat pins all eligible regions.\n\nThe unpin path is unaffected: configfs_undepend_item() only takes a\nspinlock and does not sleep.","ecosystems":[],"exploits":{"exploitdb":0,"first_seen":null,"github_poc":0,"max_poc_stars":null,"metasploit":0,"nuclei":0,"refs":[],"tier":"none_known"},"has_fix":true,"headline":"ocfs2: cluster: don't sleep while holding o2hb_live_lock in o2hb_region_pin()","id":"CVE-2026-89491","indexable":true,"kev":null,"kind":"cve","links":{"ecosystem":null,"product":null,"products":[],"type":"denial_of_service","year":"2026"},"n_packages":0,"n_references":8,"next":{"headline":"ocfs2: validate directory-index entry counts when reading metadata","id":"CVE-2026-89492"},"packages":[],"prev":{"headline":"ocfs2: fix readdir position truncation on 32-bit kernels","id":"CVE-2026-89490"},"products":["Linux"],"published":"2026-09-11","related":[],"sources":[{"class":"attribution","licence":"CVE Terms of Use (MITRE)","name":"CVE List","prefix":"CVE"}],"ssvc":{"automatable":null,"exploitation":null,"technical_impact":null},"state":"PUBLISHED","updated":"2026-10-19","vendors":["Linux"]},"summary":"A local attacker can trigger a kernel bug or deadlock in the OCFS2 cluster module by mounting a filesystem, causing a denial of service.","url":"https://insights.sbomify.com/CVE-2026-89491/"}