================================================================== BUG: KASAN: slab-use-after-free in JFS_SBI fs/jfs/jfs_incore.h:217 [inline] BUG: KASAN: slab-use-after-free in txLazyUnlock+0xf6/0x190 fs/jfs/jfs_txnmgr.c:2786 Read of size 8 at addr ffff888063a88798 by task syz.2.114/6676 CPU: 0 UID: 0 PID: 6676 Comm: syz.2.114 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 JFS_SBI fs/jfs/jfs_incore.h:217 [inline] txLazyUnlock+0xf6/0x190 fs/jfs/jfs_txnmgr.c:2786 lmPostGC fs/jfs/jfs_logmgr.c:843 [inline] lbmIODone+0x94c/0x16c0 fs/jfs/jfs_logmgr.c:2283 lbmWrite+0x34e/0x4a0 fs/jfs/jfs_logmgr.c:2064 lmGCwrite fs/jfs/jfs_logmgr.c:-1 [inline] lmNextPage+0x6b3/0xa00 fs/jfs/jfs_logmgr.c:604 lmWriteRecord+0x4f5/0x1ab0 fs/jfs/jfs_logmgr.c:431 lmLog+0x6f0/0xa30 fs/jfs/jfs_logmgr.c:312 dtLog fs/jfs/jfs_txnmgr.c:1620 [inline] txLog fs/jfs/jfs_txnmgr.c:1402 [inline] txCommit+0x1c20/0x5410 fs/jfs/jfs_txnmgr.c:1266 jfs_create+0x8f4/0xb10 fs/jfs/namei.c:157 lookup_open fs/namei.c:4511 [inline] open_last_lookups fs/namei.c:4611 [inline] path_openat+0x13b4/0x38a0 fs/namei.c:4855 do_file_open+0x23e/0x4a0 fs/namei.c:4887 do_sys_openat2+0x113/0x200 fs/open.c:1364 do_sys_open fs/open.c:1370 [inline] __do_sys_creat fs/open.c:1448 [inline] __se_sys_creat fs/open.c:1442 [inline] __x64_sys_creat+0x8f/0xc0 fs/open.c:1442 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0x174/0x580 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f54cd5dce59 Code: ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 44 00 00 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 e8 ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007f54cb7f4028 EFLAGS: 00000246 ORIG_RAX: 0000000000000055 RAX: ffffffffffffffda RBX: 00007f54cd856180 RCX: 00007f54cd5dce59 RDX: 0000000000000000 RSI: 0000000000000009 RDI: 0000200000000e00 RBP: 00007f54cd672d6f R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007f54cd856218 R14: 00007f54cd856180 R15: 00007ffe9bc08458 Allocated by task 6531: kasan_save_stack mm/kasan/common.c:57 [inline] kasan_save_track+0x3e/0x80 mm/kasan/common.c:78 poison_kmalloc_redzone mm/kasan/common.c:398 [inline] __kasan_kmalloc+0x93/0xb0 mm/kasan/common.c:415 kasan_kmalloc include/linux/kasan.h:263 [inline] __kmalloc_cache_noprof+0x3a6/0x690 mm/slub.c:5420 kmalloc_noprof include/linux/slab.h:950 [inline] kzalloc_noprof include/linux/slab.h:1188 [inline] alloc_super+0x5b/0xac0 fs/super.c:320 sget_fc+0x329/0xa40 fs/super.c:764 sget_dev fs/super.c:1408 [inline] get_tree_bdev_flags+0x214/0x4f0 fs/super.c:1680 vfs_get_tree+0x92/0x2a0 fs/super.c:1754 fc_mount fs/namespace.c:1193 [inline] do_new_mount_fc fs/namespace.c:3758 [inline] do_new_mount+0x341/0xd30 fs/namespace.c:3834 do_mount fs/namespace.c:4167 [inline] __do_sys_mount fs/namespace.c:4383 [inline] __se_sys_mount+0x31d/0x420 fs/namespace.c:4360 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0x174/0x580 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f Freed by task 9: 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] kfree+0x1c5/0x6c0 mm/slub.c:6566 process_one_work kernel/workqueue.c:3314 [inline] process_scheduled_works+0xb5d/0x1860 kernel/workqueue.c:3397 worker_thread+0xa53/0xfc0 kernel/workqueue.c:3478 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 Last potentially related work creation: kasan_save_stack+0x3e/0x60 mm/kasan/common.c:57 kasan_record_aux_stack+0xbd/0xd0 mm/kasan/generic.c:556 insert_work+0x3d/0x330 kernel/workqueue.c:2226 __queue_work+0xd1d/0x1090 kernel/workqueue.c:2393 queue_work_on+0x106/0x1d0 kernel/workqueue.c:2444 rcu_do_batch kernel/rcu/tree.c:2617 [inline] rcu_core kernel/rcu/tree.c:2869 [inline] rcu_cpu_kthread+0x99e/0x1470 kernel/rcu/tree.c:2957 smpboot_thread_fn+0x541/0xa50 kernel/smpboot.c:160 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 Second to last potentially related work creation: kasan_save_stack+0x3e/0x60 mm/kasan/common.c:57 kasan_record_aux_stack+0xbd/0xd0 mm/kasan/generic.c:556 __call_rcu_common kernel/rcu/tree.c:3131 [inline] call_rcu+0xee/0x890 kernel/rcu/tree.c:3251 put_super fs/super.c:428 [inline] deactivate_locked_super+0xf8/0x130 fs/super.c:489 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+0x193/0x680 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+0x353/0x580 arch/x86/entry/syscall_64.c:100 entry_SYSCALL_64_after_hwframe+0x77/0x7f The buggy address belongs to the object at ffff888063a88000 which belongs to the cache kmalloc-4k of size 4096 The buggy address is located 1944 bytes inside of freed 4096-byte region [ffff888063a88000, ffff888063a89000) The buggy address belongs to the physical page: page: refcount:0 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x63a88 head: order:3 mapcount:0 entire_mapcount:0 nr_pages_mapped:0 pincount:0 flags: 0x80000000000040(head|node=0|zone=1) page_type: f5(slab) raw: 0080000000000040 ffff88813fe0d140 dead000000000122 0000000000000000 raw: 0000000000000000 0000000800040004 00000000f5000000 0000000000000000 head: 0080000000000040 ffff88813fe0d140 dead000000000122 0000000000000000 head: 0000000000[ 180.183471][ T6676] head: 0000000000000000 0000000800040004 00000000f5000000 0000000000000000 head: 0080000000000003 fffffffffffffe01 00000000ffffffff 00000000ffffffff head: 0000000000000000 0000000000000000 00000000ffffffff 0000000000000008 page dumped because: kasan: bad access detected page_owner tracks the page as allocated page last allocated via order 3, migratetype Unmovable, gfp_mask 0xd2040(__GFP_IO|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP|__GFP_NOMEMALLOC), pid 4966, tgid 4966 (udevd), ts 167692305626, free_ts 167660608114 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] __do_kmalloc_node mm/slub.c:5295 [inline] __kmalloc_noprof+0x530/0x7b0 mm/slub.c:5308 kmalloc_noprof include/linux/slab.h:954 [inline] tomoyo_realpath_from_path+0xe3/0x5d0 security/tomoyo/realpath.c:251 tomoyo_get_realpath security/tomoyo/file.c:151 [inline] tomoyo_check_open_permission+0x229/0x470 security/tomoyo/file.c:776 security_file_open+0xa9/0x240 security/security.c:2739 do_dentry_open+0x4c0/0x13e0 fs/open.c:924 vfs_open+0x3b/0x350 fs/open.c:1079 do_open fs/namei.c:4699 [inline] path_openat+0x2e43/0x38a0 fs/namei.c:4858 do_file_open+0x23e/0x4a0 fs/namei.c:4887 do_sys_openat2+0x113/0x200 fs/open.c:1364 do_sys_open fs/open.c:1370 [inline] __do_sys_openat fs/open.c:1386 [inline] __se_sys_openat fs/open.c:1381 [inline] __x64_sys_openat+0x138/0x170 fs/open.c:1381 page last free pid 6527 tgid 6526 stack trace: create_dummy_stack mm/page_owner.c:103 [inline] register_dummy_stack+0x98/0x100 mm/page_owner.c:109 init_page_owner+0x2e/0x600 mm/page_owner.c:127 invoke_init_callbacks mm/page_ext.c:152 [inline] page_ext_init+0x500/0x540 mm/page_ext.c:490 mm_core_init+0x97/0xb0 mm/mm_init.c:2738 Memory state around the buggy address: ffff888063a88680: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff888063a88700: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb >ffff888063a88780: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff888063a88800: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff888063a88880: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ==================================================================