================================================================== BUG: KASAN: slab-use-after-free in dtCompare fs/jfs/jfs_dtree.c:3345 [inline] BUG: KASAN: slab-use-after-free in dtSearch+0x1683/0x21b0 fs/jfs/jfs_dtree.c:650 Read of size 1 at addr ffff88805c7f1c08 by task syz.6.348/9421 CPU: 1 UID: 0 PID: 9421 Comm: syz.6.348 Not tainted syzkaller #0 PREEMPT_{RT,(full)} Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/25/2025 Call Trace: dump_stack_lvl+0x189/0x250 lib/dump_stack.c:120 print_address_description mm/kasan/report.c:378 [inline] print_report+0xca/0x240 mm/kasan/report.c:482 kasan_report+0x118/0x150 mm/kasan/report.c:595 dtCompare fs/jfs/jfs_dtree.c:3345 [inline] dtSearch+0x1683/0x21b0 fs/jfs/jfs_dtree.c:650 jfs_lookup+0x155/0x380 fs/jfs/namei.c:1461 __lookup_slow+0x29d/0x3d0 fs/namei.c:1858 lookup_slow+0x53/0x70 fs/namei.c:1875 walk_component fs/namei.c:2221 [inline] link_path_walk+0xd1e/0x18d0 fs/namei.c:2589 path_lookupat+0xe4/0x8c0 fs/namei.c:2745 do_o_path+0x97/0x1f0 fs/namei.c:4758 path_openat+0x3674/0x3df0 fs/namei.c:4780 do_filp_open+0x1fa/0x410 fs/namei.c:4814 do_sys_openat2+0x121/0x200 fs/open.c:1430 do_sys_open fs/open.c:1436 [inline] __do_sys_openat fs/open.c:1452 [inline] __se_sys_openat fs/open.c:1447 [inline] __x64_sys_openat+0x138/0x170 fs/open.c:1447 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xfa/0xf80 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f31a9dbf749 Code: ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 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 a8 ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007f31a7fe4038 EFLAGS: 00000246 ORIG_RAX: 0000000000000101 RAX: ffffffffffffffda RBX: 00007f31aa016180 RCX: 00007f31a9dbf749 RDX: 0000000000200002 RSI: 00002000000000c0 RDI: ffffffffffffff9c RBP: 00007f31a9e43f91 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007f31aa016218 R14: 00007f31aa016180 R15: 00007ffeba1efae8 Allocated by task 9059: kasan_save_stack mm/kasan/common.c:56 [inline] kasan_save_track+0x3e/0x80 mm/kasan/common.c:77 unpoison_slab_object mm/kasan/common.c:339 [inline] __kasan_slab_alloc+0x6c/0x80 mm/kasan/common.c:365 kasan_slab_alloc include/linux/kasan.h:252 [inline] slab_post_alloc_hook mm/slub.c:4948 [inline] slab_alloc_node mm/slub.c:5258 [inline] kmem_cache_alloc_lru_noprof+0x193/0x6c0 mm/slub.c:5277 jfs_alloc_inode+0x28/0x70 fs/jfs/super.c:105 alloc_inode+0x6a/0x1b0 fs/inode.c:346 new_inode+0x22/0x170 fs/inode.c:1175 diReadSpecial+0x52/0x710 fs/jfs/jfs_imap.c:426 jfs_mount+0x3d1/0x870 fs/jfs/jfs_mount.c:166 jfs_fill_super+0x6bc/0xd80 fs/jfs/super.c:523 get_tree_bdev_flags+0x40e/0x4d0 fs/super.c:1691 vfs_get_tree+0x92/0x2a0 fs/super.c:1751 fc_mount fs/namespace.c:1199 [inline] do_new_mount_fc fs/namespace.c:3636 [inline] do_new_mount+0x302/0xa10 fs/namespace.c:3712 do_mount fs/namespace.c:4035 [inline] __do_sys_mount fs/namespace.c:4224 [inline] __se_sys_mount+0x313/0x410 fs/namespace.c:4201 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xfa/0xf80 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f Freed by task 20: kasan_save_stack mm/kasan/common.c:56 [inline] kasan_save_track+0x3e/0x80 mm/kasan/common.c:77 kasan_save_free_info+0x46/0x50 mm/kasan/generic.c:584 poison_slab_object mm/kasan/common.c:252 [inline] __kasan_slab_free+0x5c/0x80 mm/kasan/common.c:284 kasan_slab_free include/linux/kasan.h:234 [inline] slab_free_hook mm/slub.c:2540 [inline] slab_free mm/slub.c:6663 [inline] kmem_cache_free+0x18f/0x8d0 mm/slub.c:6774 rcu_do_batch kernel/rcu/tree.c:2605 [inline] rcu_core kernel/rcu/tree.c:2857 [inline] rcu_cpu_kthread+0xc96/0x1c40 kernel/rcu/tree.c:2945 smpboot_thread_fn+0x542/0xa60 kernel/smpboot.c:160 kthread+0x711/0x8a0 kernel/kthread.c:463 ret_from_fork+0x599/0xb30 arch/x86/kernel/process.c:158 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:246 Last potentially related work creation: kasan_save_stack+0x3e/0x60 mm/kasan/common.c:56 kasan_record_aux_stack+0xbd/0xd0 mm/kasan/generic.c:556 __call_rcu_common kernel/rcu/tree.c:3119 [inline] call_rcu+0x157/0x9c0 kernel/rcu/tree.c:3239 destroy_inode fs/inode.c:401 [inline] evict+0x931/0xae0 fs/inode.c:861 jfs_umount+0x199/0x3c0 fs/jfs/jfs_umount.c:65 jfs_put_super+0x8c/0x190 fs/jfs/super.c:194 generic_shutdown_super+0x135/0x2c0 fs/super.c:643 kill_block_super+0x44/0x90 fs/super.c:1722 deactivate_locked_super+0xbc/0x130 fs/super.c:474 cleanup_mnt+0x425/0x4c0 fs/namespace.c:1318 task_work_run+0x1d4/0x260 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:44 [inline] exit_to_user_mode_loop+0xff/0x4f0 kernel/entry/common.c:75 __exit_to_user_mode_prepare include/linux/irq-entry-common.h:226 [inline] syscall_exit_to_user_mode_prepare include/linux/irq-entry-common.h:256 [inline] syscall_exit_to_user_mode_work include/linux/entry-common.h:159 [inline] syscall_exit_to_user_mode include/linux/entry-common.h:194 [inline] do_syscall_64+0x2e3/0xf80 arch/x86/entry/syscall_64.c:100 entry_SYSCALL_64_after_hwframe+0x77/0x7f The buggy address belongs to the object at ffff88805c7f1380 which belongs to the cache jfs_ip of size 2368 The buggy address is located 2184 bytes inside of freed 2368-byte region [ffff88805c7f1380, ffff88805c7f1cc0) The buggy address belongs to the physical page: page: refcount:0 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x5c7f0 head: order:3 mapcount:0 entire_mapcount:0 nr_pages_mapped:0 pincount:0 memcg:ffff888059fc1101 anon flags: 0x80000000000040(head|node=0|zone=1) page_type: f5(slab) raw: 0080000000000040 ffff88801b3fd3c0 0000000000000000 0000000000000001 raw: 0000000000000000 00000000800d000d 00000000f5000000 ffff888059fc1101 head: 0080000000000040 ffff88801b3fd3c0 0000000000000000 0000000000000001 head: 0000000000000000 00000000800d000d 00000000f5000000 ffff888059fc1101 head: 0080000000000003 ffffea000171fc01 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 Reclaimable, gfp_mask 0xd2050(__GFP_RECLAIMABLE|__GFP_IO|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP|__GFP_NOMEMALLOC), pid 7186, tgid 7184 (syz.2.195), ts 219577507729, free_ts 0 set_page_owner include/linux/page_owner.h:32 [inline] post_alloc_hook+0x234/0x290 mm/page_alloc.c:1846 prep_new_page mm/page_alloc.c:1854 [inline] get_page_from_freelist+0x28c0/0x2960 mm/page_alloc.c:3915 __alloc_frozen_pages_noprof+0x181/0x370 mm/page_alloc.c:5210 alloc_pages_mpol+0xd1/0x380 mm/mempolicy.c:2486 alloc_slab_page mm/slub.c:3075 [inline] allocate_slab+0x86/0x3b0 mm/slub.c:3248 new_slab mm/slub.c:3302 [inline] ___slab_alloc+0xb10/0x1400 mm/slub.c:4651 __slab_alloc+0xc6/0x1f0 mm/slub.c:4774 __slab_alloc_node mm/slub.c:4850 [inline] slab_alloc_node mm/slub.c:5246 [inline] kmem_cache_alloc_lru_noprof+0x104/0x6c0 mm/slub.c:5277 jfs_alloc_inode+0x28/0x70 fs/jfs/super.c:105 alloc_inode+0x6a/0x1b0 fs/inode.c:346 iget_locked+0x131/0x6a0 fs/inode.c:1470 jfs_iget+0x24/0x470 fs/jfs/inode.c:29 jfs_nfs_get_inode+0x2f/0xd0 fs/jfs/namei.c:1484 generic_fh_to_dentry+0x9f/0xf0 fs/libfs.c:1506 exportfs_decode_fh_raw+0x178/0x6e0 fs/exportfs/expfs.c:456 do_handle_to_path+0xa4/0x1a0 fs/fhandle.c:276 page_owner free stack trace missing Memory state around the buggy address: ffff88805c7f1b00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff88805c7f1b80: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb >ffff88805c7f1c00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff88805c7f1c80: fb fb fb fb fb fb fb fb fc fc fc fc fc fc fc fc ffff88805c7f1d00: fc fc fc fc fc fc fc fc 00 00 00 00 00 00 00 00 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