================================================================== BUG: KASAN: slab-use-after-free in drop_metapage fs/jfs/jfs_metapage.c:312 [inline] BUG: KASAN: slab-use-after-free in release_metapage+0x72e/0xa90 fs/jfs/jfs_metapage.c:893 Read of size 8 at addr ffff88801e32a298 by task jfsCommit/129 CPU: 1 UID: 0 PID: 129 Comm: jfsCommit Not tainted syzkaller #0 PREEMPT_{RT,(full)} Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/18/2026 Call Trace: dump_stack_lvl+0xe8/0x150 lib/dump_stack.c:120 print_address_description+0x55/0x1e0 mm/kasan/report.c:378 print_report+0x58/0x70 mm/kasan/report.c:482 kasan_report+0x117/0x150 mm/kasan/report.c:595 drop_metapage fs/jfs/jfs_metapage.c:312 [inline] release_metapage+0x72e/0xa90 fs/jfs/jfs_metapage.c:893 txUnlock+0x509/0xdb0 fs/jfs/jfs_txnmgr.c:949 txLazyCommit fs/jfs/jfs_txnmgr.c:2684 [inline] jfs_lazycommit+0x52c/0xa10 fs/jfs/jfs_txnmgr.c:2735 kthread+0x388/0x470 kernel/kthread.c:436 ret_from_fork+0x514/0xb70 arch/x86/kernel/process.c:158 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245 Allocated by task 10289: kasan_save_stack mm/kasan/common.c:57 [inline] kasan_save_track+0x3e/0x80 mm/kasan/common.c:78 unpoison_slab_object mm/kasan/common.c:340 [inline] __kasan_slab_alloc+0x6c/0x80 mm/kasan/common.c:366 kasan_slab_alloc include/linux/kasan.h:253 [inline] slab_post_alloc_hook mm/slub.c:4570 [inline] slab_alloc_node mm/slub.c:4899 [inline] kmem_cache_alloc_noprof+0x33b/0x680 mm/slub.c:4906 mempool_alloc_noprof+0x1d4/0x300 mm/mempool.c:566 alloc_metapage fs/jfs/jfs_metapage.c:264 [inline] __get_metapage+0x50c/0xe20 fs/jfs/jfs_metapage.c:761 diNewExt+0xa88/0x3150 fs/jfs/jfs_imap.c:2275 diAllocExt fs/jfs/jfs_imap.c:1952 [inline] diAllocAG+0xeb1/0x1db0 fs/jfs/jfs_imap.c:1669 diAlloc+0x1d4/0x1670 fs/jfs/jfs_imap.c:1590 ialloc+0x8c/0x8f0 fs/jfs/jfs_inode.c:56 jfs_mkdir+0x1e1/0xb00 fs/jfs/namei.c:226 vfs_mkdir+0x40b/0x630 fs/namei.c:5261 filename_mkdirat+0x289/0x520 fs/namei.c:5294 __do_sys_mkdirat fs/namei.c:5315 [inline] __se_sys_mkdirat+0x35/0x150 fs/namei.c:5312 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0x15f/0x560 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f Freed by task 8093: kasan_save_stack mm/kasan/common.c:57 [inline] kasan_save_track+0x3e/0x80 mm/kasan/common.c:78 kasan_save_free_info+0x46/0x50 mm/kasan/generic.c:584 poison_slab_object mm/kasan/common.c:253 [inline] __kasan_slab_free+0x5c/0x80 mm/kasan/common.c:285 kasan_slab_free include/linux/kasan.h:235 [inline] slab_free_hook mm/slub.c:2689 [inline] slab_free mm/slub.c:6251 [inline] kmem_cache_free+0x187/0x6c0 mm/slub.c:6378 mempool_free+0xf5/0x140 mm/mempool.c:711 free_metapage fs/jfs/jfs_metapage.c:280 [inline] metapage_release_folio+0x469/0x5a0 fs/jfs/jfs_metapage.c:637 folio_invalidate mm/truncate.c:140 [inline] truncate_cleanup_folio+0xcb/0x190 mm/truncate.c:160 truncate_inode_pages_range+0x2d1/0xe30 mm/truncate.c:404 jfs_put_super+0x12c/0x190 fs/jfs/super.c:200 generic_shutdown_super+0x13d/0x2d0 fs/super.c:646 kill_block_super+0x44/0x90 fs/super.c:1725 deactivate_locked_super+0xbc/0x130 fs/super.c:476 cleanup_mnt+0x437/0x4d0 fs/namespace.c:1312 task_work_run+0x1d9/0x270 kernel/task_work.c:233 resume_user_mode_work include/linux/resume_user_mode.h:50 [inline] __exit_to_user_mode_loop kernel/entry/common.c:67 [inline] exit_to_user_mode_loop+0xf3/0x4d0 kernel/entry/common.c:98 __exit_to_user_mode_prepare include/linux/irq-entry-common.h:207 [inline] syscall_exit_to_user_mode_prepare include/linux/irq-entry-common.h:230 [inline] syscall_exit_to_user_mode include/linux/entry-common.h:318 [inline] do_syscall_64+0x33e/0x560 arch/x86/entry/syscall_64.c:100 entry_SYSCALL_64_after_hwframe+0x77/0x7f The buggy address belongs to the object at ffff88801e32a270 which belongs to the cache jfs_mp of size 248 The buggy address is located 40 bytes inside of freed 248-byte region [ffff88801e32a270, ffff88801e32a368) The buggy address belongs to the physical page: page: refcount:0 mapcount:0 mapping:0000000000000000 index:0xffff88801e32a4e0 pfn:0x1e32a flags: 0x80000000000200(workingset|node=0|zone=1) page_type: f5(slab) raw: 0080000000000200 ffff888140ec9b40 ffff88801e30cc88 ffffea000078cad0 raw: ffff88801e32a4e0 00000008000d0009 00000000f5000000 0000000000000000 page dumped because: kasan: bad access detected page_owner tracks the page as allocated page last allocated via order 0, migratetype Unmovable, gfp_mask 0xd2cc0(GFP_KERNEL|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP|__GFP_NOMEMALLOC), pid 1, tgid 1 (swapper/0), ts 5807848450, free_ts 0 set_page_owner include/linux/page_owner.h:32 [inline] post_alloc_hook+0x22d/0x280 mm/page_alloc.c:1853 prep_new_page mm/page_alloc.c:1861 [inline] get_page_from_freelist+0x28b2/0x2930 mm/page_alloc.c:3941 __alloc_frozen_pages_noprof+0x18d/0x380 mm/page_alloc.c:5221 alloc_slab_page mm/slub.c:3278 [inline] allocate_slab+0x77/0x660 mm/slub.c:3467 new_slab mm/slub.c:3525 [inline] refill_objects+0x33c/0x3d0 mm/slub.c:7272 refill_sheaf mm/slub.c:2816 [inline] __pcs_replace_empty_main+0x373/0x720 mm/slub.c:4652 alloc_from_pcs mm/slub.c:4750 [inline] slab_alloc_node mm/slub.c:4884 [inline] kmem_cache_alloc_noprof+0x433/0x680 mm/slub.c:4906 mempool_init_node+0x210/0x4f0 mm/mempool.c:259 mempool_create_node_noprof+0xb8/0x150 mm/mempool.c:323 metapage_init+0xed/0x150 fs/jfs/jfs_metapage.c:293 init_jfs_fs+0xfd/0x4e0 fs/jfs/super.c:968 do_one_initcall+0x250/0x870 init/main.c:1392 do_initcall_level+0x104/0x190 init/main.c:1454 do_initcalls+0x59/0xa0 init/main.c:1470 kernel_init_freeable+0x2a6/0x3e0 init/main.c:1703 kernel_init+0x1d/0x1d0 init/main.c:1593 page_owner free stack trace missing Memory state around the buggy address: ffff88801e32a180: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff88801e32a200: fb fb fb fb fb fb fc fc fc fc fc fc fc fc fa fb >ffff88801e32a280: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff88801e32a300: fb fb fb fb fb fb fb fb fb fb fb fb fb fc fc fc ffff88801e32a380: fc fc fc fc fc fa fb fb fb fb fb fb fb fb fb fb ==================================================================