==================================================================
BUG: KASAN: slab-out-of-bounds in ciCompare fs/jfs/jfs_dtree.c:3428 [inline]
BUG: KASAN: slab-out-of-bounds in dtSearch+0x16b4/0x21b0 fs/jfs/jfs_dtree.c:645
Read of size 1 at addr ffff88805c5deb84 by task syz.6.204/7978

CPU: 0 UID: 0 PID: 7978 Comm: syz.6.204 Not tainted syzkaller #0 PREEMPT_{RT,(full)} 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/12/2025
Call Trace:
 <TASK>
 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
 ciCompare fs/jfs/jfs_dtree.c:3428 [inline]
 dtSearch+0x16b4/0x21b0 fs/jfs/jfs_dtree.c:645
 jfs_lookup+0x155/0x380 fs/jfs/namei.c:1461
 lookup_one_qstr_excl+0x12e/0x360 fs/namei.c:1697
 filename_create+0x224/0x3c0 fs/namei.c:4140
 do_mkdirat+0xa0/0x590 fs/namei.c:4391
 __do_sys_mkdir fs/namei.c:4421 [inline]
 __se_sys_mkdir fs/namei.c:4419 [inline]
 __x64_sys_mkdir+0x6c/0x80 fs/namei.c:4419
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0xfa/0x3b0 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f60caf0ebe9
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:00007f60c8d09038 EFLAGS: 00000246 ORIG_RAX: 0000000000000053
RAX: ffffffffffffffda RBX: 00007f60cb136270 RCX: 00007f60caf0ebe9
RDX: 0000000000000000 RSI: 0000000000000010 RDI: 0000200000000200
RBP: 00007f60caf91e19 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f60cb136308 R14: 00007f60cb136270 R15: 00007ffe3bd5bcb8
 </TASK>

Allocated by task 7947:
 kasan_save_stack mm/kasan/common.c:47 [inline]
 kasan_save_track+0x3e/0x80 mm/kasan/common.c:68
 unpoison_slab_object mm/kasan/common.c:330 [inline]
 __kasan_slab_alloc+0x6c/0x80 mm/kasan/common.c:356
 kasan_slab_alloc include/linux/kasan.h:250 [inline]
 slab_post_alloc_hook mm/slub.c:4180 [inline]
 slab_alloc_node mm/slub.c:4229 [inline]
 kmem_cache_alloc_lru_noprof+0x14c/0x310 mm/slub.c:4248
 jfs_alloc_inode+0x28/0x70 fs/jfs/super.c:105
 alloc_inode+0x6a/0x1b0 fs/inode.c:346
 iget_locked+0xf0/0x570 fs/inode.c:1438
 jfs_iget+0x24/0x3e0 fs/jfs/inode.c:29
 jfs_lookup+0x1c5/0x380 fs/jfs/namei.c:1469
 __lookup_slow+0x29a/0x3d0 fs/namei.c:1808
 lookup_slow+0x53/0x70 fs/namei.c:1825
 walk_component+0x2d2/0x400 fs/namei.c:2129
 lookup_last fs/namei.c:2630 [inline]
 path_lookupat+0x163/0x430 fs/namei.c:2654
 filename_lookup+0x212/0x570 fs/namei.c:2683
 user_path_at+0x3a/0x60 fs/namei.c:3127
 __do_sys_chdir fs/open.c:561 [inline]
 __se_sys_chdir+0x91/0x280 fs/open.c:555
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0xfa/0x3b0 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

The buggy address belongs to the object at ffff88805c5de220
 which belongs to the cache jfs_ip of size 2384
The buggy address is located 20 bytes to the right of
 allocated 2384-byte region [ffff88805c5de220, ffff88805c5deb70)

The buggy address belongs to the physical page:
page: refcount:0 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x5c5d8
head: order:3 mapcount:0 entire_mapcount:0 nr_pages_mapped:0 pincount:0
memcg:ffff8880313ae901
flags: 0x80000000000040(head|node=0|zone=1)
page_type: f5(slab)
raw: 0080000000000040 ffff8881466c13c0 dead000000000122 0000000000000000
raw: 0000000000000000 00000000800d000d 00000000f5000000 ffff8880313ae901
head: 0080000000000040 ffff8881466c13c0 dead000000000122 0000000000000000
head: 0000000000000000 00000000800d000d 00000000f5000000 ffff8880313ae901
head: 0080000000000003 ffffea0001717601 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 6988, tgid 6987 (syz.1.138), ts 218168559666, free_ts 217556458165
 set_page_owner include/linux/page_owner.h:32 [inline]
 post_alloc_hook+0x240/0x2a0 mm/page_alloc.c:1851
 prep_new_page mm/page_alloc.c:1859 [inline]
 get_page_from_freelist+0x2119/0x21b0 mm/page_alloc.c:3858
 __alloc_frozen_pages_noprof+0x181/0x370 mm/page_alloc.c:5148
 alloc_pages_mpol+0xd1/0x380 mm/mempolicy.c:2416
 alloc_slab_page mm/slub.c:2487 [inline]
 allocate_slab+0x8a/0x370 mm/slub.c:2655
 new_slab mm/slub.c:2709 [inline]
 ___slab_alloc+0x8d1/0xdd0 mm/slub.c:3891
 __slab_alloc mm/slub.c:3981 [inline]
 __slab_alloc_node mm/slub.c:4056 [inline]
 slab_alloc_node mm/slub.c:4217 [inline]
 kmem_cache_alloc_lru_noprof+0xea/0x310 mm/slub.c:4248
 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:1145
 ialloc+0x4c/0x8f0 fs/jfs/jfs_inode.c:48
 jfs_create+0x18d/0xa80 fs/jfs/namei.c:92
 vfs_create+0x24e/0x400 fs/namei.c:3405
 do_mknodat+0x3c6/0x4d0 fs/namei.c:4285
 __do_sys_mknod fs/namei.c:4318 [inline]
 __se_sys_mknod fs/namei.c:4316 [inline]
 __x64_sys_mknod+0x8c/0xa0 fs/namei.c:4316
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0xfa/0x3b0 arch/x86/entry/syscall_64.c:94
page last free pid 5838 tgid 5838 stack trace:
 reset_page_owner include/linux/page_owner.h:25 [inline]
 free_pages_prepare mm/page_alloc.c:1395 [inline]
 __free_frozen_pages+0xb59/0xce0 mm/page_alloc.c:2895
 free_large_kmalloc+0x13a/0x1f0 mm/slub.c:4805
 __btree_node_data_free+0x2bb/0x3a0 fs/bcachefs/btree_cache.c:107
 btree_node_data_free+0x13f/0x340 fs/bcachefs/btree_cache.c:122
 bch2_fs_btree_cache_exit+0x9c1/0x13c0 fs/bcachefs/btree_cache.c:609
 __bch2_fs_free fs/bcachefs/super.c:619 [inline]
 bch2_fs_release+0x2bb/0x830 fs/bcachefs/super.c:667
 kobject_cleanup lib/kobject.c:689 [inline]
 kobject_release lib/kobject.c:720 [inline]
 kref_put include/linux/kref.h:65 [inline]
 kobject_put+0x22b/0x480 lib/kobject.c:737
 deactivate_locked_super+0xbc/0x130 fs/super.c:474
 cleanup_mnt+0x425/0x4c0 fs/namespace.c:1375
 task_work_run+0x1d4/0x260 kernel/task_work.c:227
 resume_user_mode_work include/linux/resume_user_mode.h:50 [inline]
 exit_to_user_mode_loop+0xec/0x110 kernel/entry/common.c:43
 exit_to_user_mode_prepare include/linux/irq-entry-common.h:225 [inline]
 syscall_exit_to_user_mode_work include/linux/entry-common.h:175 [inline]
 syscall_exit_to_user_mode include/linux/entry-common.h:210 [inline]
 do_syscall_64+0x2bd/0x3b0 arch/x86/entry/syscall_64.c:100
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

Memory state around the buggy address:
 ffff88805c5dea80: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
 ffff88805c5deb00: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 fc fc
>ffff88805c5deb80: fc fc fc fc fc fc fc fc fc fc fc fc fc fc 00 00
                   ^
 ffff88805c5dec00: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
 ffff88805c5dec80: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
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