{"cve":"CVE-2026-89496","nvd":{"published":"2026-09-11T20:19:31.657","modified":"2026-10-19T09:17:43.667","status":"Received","description":"In the Linux kernel, the following vulnerability has been resolved:\n\nocfs2: always run deallocs on copy-on-write completion\n\nLocal fuzzing of 6.12.94 has found the following memory leak\ncaused by doing 'copy_file_range()' within the same filesystem:\n\nunreferenced object 0xffff88812192c980 (size 32):\n  comm \"syz.0.49\", pid 12095, jiffies 4294964143\n  hex dump (first 32 bytes):\n    00 00 00 00 00 00 00 00 08 00 00 00 00 00 00 00  ................\n    c0 c5 92 21 81 88 ff ff 00 02 00 00 00 06 00 00  ...!............\n  backtrace (crc 7068d63f):\n    kmemleak_alloc_recursive include/linux/kmemleak.h:42 [inline]\n    slab_post_alloc_hook mm/slub.c:4152 [inline]\n    slab_alloc_node mm/slub.c:4197 [inline]\n    __kmalloc_cache_noprof+0x168/0x2c0 mm/slub.c:4358\n    kmalloc_noprof include/linux/slab.h:878 [inline]\n    ocfs2_find_per_slot_free_list fs/ocfs2/alloc.c:6618 [inline]\n    ocfs2_cache_block_dealloc+0x155/0x4b0 fs/ocfs2/alloc.c:6786\n    ocfs2_cache_extent_block_free fs/ocfs2/alloc.c:6819 [inline]\n    ocfs2_unlink_path+0x286/0x450 fs/ocfs2/alloc.c:2613\n    ocfs2_rotate_subtree_left fs/ocfs2/alloc.c:2779 [inline]\n    __ocfs2_rotate_tree_left+0x1f6f/0x2da0 fs/ocfs2/alloc.c:2985\n    ocfs2_rotate_tree_left+0x283/0xe00 fs/ocfs2/alloc.c:3237\n    ocfs2_try_to_merge_extent+0xf56/0x1a20 fs/ocfs2/alloc.c:3825\n    ocfs2_split_extent+0x15f4/0x2940 fs/ocfs2/alloc.c:5138\n    ocfs2_clear_ext_refcount+0x2f6/0x550 fs/ocfs2/refcounttree.c:3098\n    ocfs2_replace_clusters fs/ocfs2/refcounttree.c:3131 [inline]\n    ocfs2_make_clusters_writable fs/ocfs2/refcounttree.c:3255 [inline]\n    ocfs2_replace_cow+0x991/0x1660 fs/ocfs2/refcounttree.c:3349\n    ocfs2_refcount_cow_hunk fs/ocfs2/refcounttree.c:3427 [inline]\n    ocfs2_refcount_cow+0x5e1/0x9f0 fs/ocfs2/refcounttree.c:3470\n    ocfs2_prepare_inode_for_write fs/ocfs2/file.c:2340 [inline]\n    ocfs2_file_write_iter+0xbda/0x1880 fs/ocfs2/file.c:2451\n    iter_file_splice_write+0x890/0xf60 fs/splice.c:743\n    do_splice_from fs/splice.c:944 [inline]\n    direct_splice_actor+0x232/0x480 fs/splice.c:1167\n    splice_direct_to_actor+0x4b4/0xb60 fs/splice.c:1111\n    do_splice_direct_actor fs/splice.c:1210 [inline]\n    do_splice_direct+0x10f/0x1c0 fs/splice.c:1236\n    do_sendfile+0x430/0xbf0 fs/read_write.c:1388\n\nunreferenced object 0xffff88812192c5c0 (size 32):\n  comm \"syz.0.49\", pid 12095, jiffies 4294964143\n  hex dump (first 32 bytes):\n    00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00  ................\n    29 70 00 00 00 00 00 00 19 00 00 00 00 00 00 00  )p..............\n  backtrace (crc afec850f):\n    kmemleak_alloc_recursive include/linux/kmemleak.h:42 [inline]\n    slab_post_alloc_hook mm/slub.c:4152 [inline]\n    slab_alloc_node mm/slub.c:4197 [inline]\n    __kmalloc_cache_noprof+0x168/0x2c0 mm/slub.c:4358\n    kmalloc_noprof include/linux/slab.h:878 [inline]\n    kzalloc_noprof include/linux/slab.h:1014 [inline]\n    ocfs2_cache_block_dealloc+0x25c/0x4b0 fs/ocfs2/alloc.c:6793\n    ocfs2_cache_extent_block_free fs/ocfs2/alloc.c:6819 [inline]\n    ocfs2_unlink_path+0x286/0x450 fs/ocfs2/alloc.c:2613\n    ocfs2_rotate_subtree_left fs/ocfs2/alloc.c:2779 [inline]\n    __ocfs2_rotate_tree_left+0x1f6f/0x2da0 fs/ocfs2/alloc.c:2985\n    ocfs2_rotate_tree_left+0x283/0xe00 fs/ocfs2/alloc.c:3237\n    ocfs2_try_to_merge_extent+0xf56/0x1a20 fs/ocfs2/alloc.c:3825\n    ocfs2_split_extent+0x15f4/0x2940 fs/ocfs2/alloc.c:5138\n    ocfs2_clear_ext_refcount+0x2f6/0x550 fs/ocfs2/refcounttree.c:3098\n    ocfs2_replace_clusters fs/ocfs2/refcounttree.c:3131 [inline]\n    ocfs2_make_clusters_writable fs/ocfs2/refcounttree.c:3255 [inline]\n    ocfs2_replace_cow+0x991/0x1660 fs/ocfs2/refcounttree.c:3349\n    ocfs2_refcount_cow_hunk fs/ocfs2/refcounttree.c:3427 [inline]\n    ocfs2_refcount_cow+0x5e1/0x9f0 fs/ocfs2/refcounttree.c:3470\n    ocfs2_prepare_inode_for_write fs/ocfs2/file.c:2340 [inline]\n    ocfs2_file_write_iter+0xbda/0x1880 fs/ocfs2/file.c:2451\n    iter_file_splice_write+0x890/0xf60 fs/splice.c:743\n    do_splice_from fs/splice.c:9\n---truncated---","cvss_v4":null,"cvss_v3":null,"cwes":[],"references":["https://git.kernel.org/stable/c/09e93a60e18e83a630ff84ae00cb564bab96ab1f","https://git.kernel.org/stable/c/123c050eb96aae0bab74c9f06c6ad3de7992722b","https://git.kernel.org/stable/c/2753e12853ed2023555cec2c5fe22fbaabb2c0b7","https://git.kernel.org/stable/c/5ff30f07def6d0e6edacf47952807b5ff60f3af6","https://git.kernel.org/stable/c/71f07b7f90b3109c9098d1b9c8efbbeece5deb8a"],"products":[],"source":"nvd","synced_at":"2026-10-19T22:53:43.293028046+00:00"},"epss":{"cve":"CVE-2026-89496","score":0.00177,"percentile":0.0715,"date":"2026-10-25"},"kev":null,"osv":[],"attribution":["This product uses the NVD API but is not endorsed or certified by the NVD.","EPSS scores: FIRST Exploit Prediction Scoring System, https://www.first.org/epss","Known exploited vulnerabilities: CISA Known Exploited Vulnerabilities Catalog, https://www.cisa.gov/known-exploited-vulnerabilities-catalog","Package advisories: OSV (https://osv.dev), from the GitHub Advisory Database, PyPA, Go, RustSec and other ecosystem databases, under CC-BY 4.0 or CC0","CVE records: the CVE Program's CVE List (https://www.cve.org), under its terms of use (https://www.cve.org/Legal/TermsOfUse). CVE is a registered trademark of The MITRE Corporation; this product is not affiliated with the CVE Program."]}