incfs: ino conflict with backing FS 1
==================================================================
BUG: KASAN: slab-out-of-bounds in inode_test+0xd9/0x190 fs/incfs/vfs.c:325
Read of size 8 at addr ffff888128407320 by task syz.4.992/5270

CPU: 0 PID: 5270 Comm: syz.4.992 Not tainted 5.15.156-syzkaller-00821-g29d153aabd54 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 06/27/2024
Call Trace:
 <TASK>
 __dump_stack lib/dump_stack.c:88 [inline]
 dump_stack_lvl+0x151/0x1c0 lib/dump_stack.c:106
 print_address_description+0x87/0x3b0 mm/kasan/report.c:248
 __kasan_report mm/kasan/report.c:427 [inline]
 kasan_report+0x179/0x1c0 mm/kasan/report.c:444
 __asan_report_load8_noabort+0x14/0x20 mm/kasan/report_generic.c:309
 inode_test+0xd9/0x190 fs/incfs/vfs.c:325
 find_inode+0x16b/0x430 fs/inode.c:834
 ilookup5_nowait fs/inode.c:1386 [inline]
 ilookup5+0xa0/0x1d0 fs/inode.c:1415
 iget5_locked+0x37/0x280 fs/inode.c:1196
 fetch_regular_inode+0x266/0x330 fs/incfs/vfs.c:384
 dir_lookup+0x5fb/0x680 fs/incfs/vfs.c:1037
 __lookup_slow+0x2b9/0x400 fs/namei.c:1663
 lookup_one_len+0x187/0x2c0 fs/namei.c:2718
 ovl_check_whiteouts fs/overlayfs/readdir.c:281 [inline]
 ovl_dir_read+0x3d4/0x530 fs/overlayfs/readdir.c:315
 ovl_dir_read_merged+0x268/0x530 fs/overlayfs/readdir.c:362
 ovl_cache_get fs/overlayfs/readdir.c:414 [inline]
 ovl_iterate+0x1065/0x2030 fs/overlayfs/readdir.c:764
 iterate_dir+0x265/0x610
 __do_sys_getdents64 fs/readdir.c:369 [inline]
 __se_sys_getdents64+0x1c1/0x460 fs/readdir.c:354
 __x64_sys_getdents64+0x7b/0x90 fs/readdir.c:354
 x64_sys_call+0x5ae/0x9a0 arch/x86/include/generated/asm/syscalls_64.h:218
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x3b/0xb0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x66/0xd0
RIP: 0033:0x7fdcfc5c4e79
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:00007fdcfb221038 EFLAGS: 00000246 ORIG_RAX: 00000000000000d9
RAX: ffffffffffffffda RBX: 00007fdcfc761058 RCX: 00007fdcfc5c4e79
RDX: 0000000000000029 RSI: 9999999999999999 RDI: 0000000000000008
RBP: 00007fdcfc63293e R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 0000000000000000 R14: 00007fdcfc761058 R15: 00007ffff2089028
 </TASK>

Allocated by task 4614:
 kasan_save_stack mm/kasan/common.c:38 [inline]
 kasan_set_track mm/kasan/common.c:45 [inline]
 set_alloc_info mm/kasan/common.c:433 [inline]
 __kasan_slab_alloc+0xb1/0xe0 mm/kasan/common.c:466
 kasan_slab_alloc include/linux/kasan.h:217 [inline]
 slab_post_alloc_hook+0x53/0x2c0 mm/slab.h:550
 slab_alloc_node mm/slub.c:3240 [inline]
 slab_alloc mm/slub.c:3248 [inline]
 kmem_cache_alloc+0xf5/0x200 mm/slub.c:3253
 f2fs_kmem_cache_alloc fs/f2fs/f2fs.h:2805 [inline]
 f2fs_alloc_inode+0x26/0x340 fs/f2fs/super.c:1406
 alloc_inode fs/inode.c:236 [inline]
 iget_locked+0x174/0x860 fs/inode.c:1244
 f2fs_iget+0x55/0x5040 fs/f2fs/inode.c:498
 f2fs_fill_super+0x4eed/0x8170 fs/f2fs/super.c:4265
 mount_bdev+0x282/0x3b0 fs/super.c:1387
 f2fs_mount+0x34/0x40 fs/f2fs/super.c:4625
 legacy_get_tree+0xf1/0x190 fs/fs_context.c:611
 vfs_get_tree+0x88/0x290 fs/super.c:1517
 do_new_mount+0x2ba/0xb30 fs/namespace.c:3005
 path_mount+0x671/0x1070 fs/namespace.c:3335
 do_mount fs/namespace.c:3348 [inline]
 __do_sys_mount fs/namespace.c:3556 [inline]
 __se_sys_mount+0x2c4/0x3b0 fs/namespace.c:3533
 __x64_sys_mount+0xbf/0xd0 fs/namespace.c:3533
 x64_sys_call+0x49d/0x9a0 arch/x86/include/generated/asm/syscalls_64.h:166
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x3b/0xb0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x66/0xd0

Last potentially related work creation:
 kasan_save_stack+0x3b/0x60 mm/kasan/common.c:38
 __kasan_record_aux_stack+0xd3/0xf0 mm/kasan/generic.c:348
 kasan_record_aux_stack_noalloc+0xb/0x10 mm/kasan/generic.c:358
 __call_rcu_common kernel/rcu/tree.c:3007 [inline]
 call_rcu+0x135/0x1310 kernel/rcu/tree.c:3125
 destroy_inode fs/inode.c:291 [inline]
 evict+0x5df/0x630 fs/inode.c:602
 iput_final fs/inode.c:1705 [inline]
 iput+0x63b/0x7e0 fs/inode.c:1731
 f2fs_put_super+0x683/0xc10 fs/f2fs/super.c:1638
 generic_shutdown_super+0x157/0x2e0 fs/super.c:475
 kill_block_super+0x7e/0xe0 fs/super.c:1414
 kill_f2fs_super+0x2f9/0x3c0 fs/f2fs/super.c:4657
 deactivate_locked_super+0xad/0x110 fs/super.c:335
 deactivate_super+0xbe/0xf0 fs/super.c:366
 cleanup_mnt+0x45c/0x510 fs/namespace.c:1143
 __cleanup_mnt+0x19/0x20 fs/namespace.c:1150
 task_work_run+0x129/0x190 kernel/task_work.c:164
 tracehook_notify_resume include/linux/tracehook.h:189 [inline]
 exit_to_user_mode_loop+0xc4/0xe0 kernel/entry/common.c:181
 exit_to_user_mode_prepare+0x5a/0xa0 kernel/entry/common.c:214
 __syscall_exit_to_user_mode_work kernel/entry/common.c:296 [inline]
 syscall_exit_to_user_mode+0x26/0x160 kernel/entry/common.c:307
 do_syscall_64+0x47/0xb0 arch/x86/entry/common.c:86
 entry_SYSCALL_64_after_hwframe+0x66/0xd0

Second to last potentially related work creation:
 kasan_save_stack+0x3b/0x60 mm/kasan/common.c:38
 __kasan_record_aux_stack+0xd3/0xf0 mm/kasan/generic.c:348
 kasan_record_aux_stack_noalloc+0xb/0x10 mm/kasan/generic.c:358
 __call_rcu_common kernel/rcu/tree.c:3007 [inline]
 call_rcu+0x135/0x1310 kernel/rcu/tree.c:3125
 destroy_inode fs/inode.c:291 [inline]
 evict+0x5df/0x630 fs/inode.c:602
 iput_final fs/inode.c:1705 [inline]
 iput+0x63b/0x7e0 fs/inode.c:1731
 f2fs_put_super+0x632/0xc10 fs/f2fs/super.c:1635
 generic_shutdown_super+0x157/0x2e0 fs/super.c:475
 kill_block_super+0x7e/0xe0 fs/super.c:1414
 kill_f2fs_super+0x2f9/0x3c0 fs/f2fs/super.c:4657
 deactivate_locked_super+0xad/0x110 fs/super.c:335
 deactivate_super+0xbe/0xf0 fs/super.c:366
 cleanup_mnt+0x45c/0x510 fs/namespace.c:1143
 __cleanup_mnt+0x19/0x20 fs/namespace.c:1150
 task_work_run+0x129/0x190 kernel/task_work.c:164
 tracehook_notify_resume include/linux/tracehook.h:189 [inline]
 exit_to_user_mode_loop+0xc4/0xe0 kernel/entry/common.c:181
 exit_to_user_mode_prepare+0x5a/0xa0 kernel/entry/common.c:214
 __syscall_exit_to_user_mode_work kernel/entry/common.c:296 [inline]
 syscall_exit_to_user_mode+0x26/0x160 kernel/entry/common.c:307
 do_syscall_64+0x47/0xb0 arch/x86/entry/common.c:86
 entry_SYSCALL_64_after_hwframe+0x66/0xd0

The buggy address belongs to the object at ffff888128406d20
 which belongs to the cache f2fs_inode_cache of size 1424
The buggy address is located 112 bytes to the right of
 1424-byte region [ffff888128406d20, ffff8881284072b0)
The buggy address belongs to the page:
page:ffffea0004a10000 refcount:1 mapcount:0 mapping:0000000000000000 index:0xffff888128406d20 pfn:0x128400
head:ffffea0004a10000 order:3 compound_mapcount:0 compound_pincount:0
flags: 0x4000000000010200(slab|head|zone=1)
raw: 4000000000010200 ffffea0004a15c00 0000000200000002 ffff8881003f1800
raw: ffff888128406d20 0000000080150011 00000001ffffffff 0000000000000000
page dumped because: kasan: bad access detected
page_owner tracks the page as allocated
page last allocated via order 3, migratetype Reclaimable, gfp_mask 0x1d2050(__GFP_IO|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP|__GFP_NOMEMALLOC|__GFP_HARDWALL|__GFP_RECLAIMABLE), pid 1729, ts 95656950756, free_ts 82145034094
 set_page_owner include/linux/page_owner.h:33 [inline]
 post_alloc_hook+0x1a3/0x1b0 mm/page_alloc.c:2605
 prep_new_page+0x1b/0x110 mm/page_alloc.c:2611
 get_page_from_freelist+0x3550/0x35d0 mm/page_alloc.c:4485
 __alloc_pages+0x27e/0x8f0 mm/page_alloc.c:5779
 allocate_slab mm/slub.c:1932 [inline]
 new_slab+0x9a/0x4e0 mm/slub.c:1995
 ___slab_alloc+0x39e/0x830 mm/slub.c:3028
 __slab_alloc+0x4a/0x90 mm/slub.c:3115
 slab_alloc_node mm/slub.c:3206 [inline]
 slab_alloc mm/slub.c:3248 [inline]
 kmem_cache_alloc+0x134/0x200 mm/slub.c:3253
 f2fs_kmem_cache_alloc fs/f2fs/f2fs.h:2805 [inline]
 f2fs_alloc_inode+0x26/0x340 fs/f2fs/super.c:1406
 alloc_inode fs/inode.c:236 [inline]
 iget_locked+0x174/0x860 fs/inode.c:1244
 f2fs_iget+0x55/0x5040 fs/f2fs/inode.c:498
 f2fs_fill_super+0x6688/0x8170 fs/f2fs/super.c:4376
 mount_bdev+0x282/0x3b0 fs/super.c:1387
 f2fs_mount+0x34/0x40 fs/f2fs/super.c:4625
 legacy_get_tree+0xf1/0x190 fs/fs_context.c:611
 vfs_get_tree+0x88/0x290 fs/super.c:1517
page last free stack trace:
 reset_page_owner include/linux/page_owner.h:26 [inline]
 free_pages_prepare mm/page_alloc.c:1472 [inline]
 free_pcp_prepare mm/page_alloc.c:1544 [inline]
 free_unref_page_prepare+0x7c8/0x7d0 mm/page_alloc.c:3534
 free_unref_page+0xe8/0x750 mm/page_alloc.c:3616
 free_the_page mm/page_alloc.c:805 [inline]
 __free_pages+0x61/0xf0 mm/page_alloc.c:5855
 __free_slab+0xec/0x1d0 mm/slub.c:2020
 free_slab mm/slub.c:2035 [inline]
 discard_slab mm/slub.c:2041 [inline]
 __unfreeze_partials+0x165/0x1a0 mm/slub.c:2527
 put_cpu_partial+0xc4/0x120 mm/slub.c:2607
 __slab_free+0x1c8/0x290 mm/slub.c:3388
 do_slab_free mm/slub.c:3507 [inline]
 ___cache_free+0x109/0x120 mm/slub.c:3526
 qlink_free+0x4d/0x90 mm/kasan/quarantine.c:157
 qlist_free_all+0x44/0xb0 mm/kasan/quarantine.c:176
 kasan_quarantine_reduce+0x15a/0x180 mm/kasan/quarantine.c:283
 __kasan_slab_alloc+0x2f/0xe0 mm/kasan/common.c:443
 kasan_slab_alloc include/linux/kasan.h:217 [inline]
 slab_post_alloc_hook+0x53/0x2c0 mm/slab.h:550
 slab_alloc_node mm/slub.c:3240 [inline]
 slab_alloc mm/slub.c:3248 [inline]
 kmem_cache_alloc+0xf5/0x200 mm/slub.c:3253
 add_free_nid+0xe9/0x6d0 fs/f2fs/node.c:2288
 scan_free_nid_bits fs/f2fs/node.c:2439 [inline]
 __f2fs_build_free_nids fs/f2fs/node.c:2473 [inline]
 f2fs_build_free_nids+0x51b/0x1180 fs/f2fs/node.c:2531

Memory state around the buggy address:
 ffff888128407200: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
 ffff888128407280: fb fb fb fb fb fb fc fc fc fc fc fc fc fc fc fc
>ffff888128407300: fc fc fc fc fc fc 00 00 00 00 00 00 00 00 00 00
                               ^
 ffff888128407380: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
 ffff888128407400: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
==================================================================