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BUG: KASAN: use-after-free in ocfs2_find_victim_chain fs/ocfs2/suballoc.c:1447 [inline]
BUG: KASAN: use-after-free in ocfs2_claim_suballoc_bits+0x8b2/0x2450 fs/ocfs2/suballoc.c:1996
Read of size 4 at addr ffff88805663b000 by task syz.0.15/5849

CPU: 0 UID: 0 PID: 5849 Comm: syz.0.15 Not tainted 6.15.0-rc6-syzkaller-00278-g172a9d94339c #0 PREEMPT(full) 
Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.3-debian-1.16.3-2~bpo12+1 04/01/2014
Call Trace:
 <TASK>
 dump_stack_lvl+0x189/0x250 lib/dump_stack.c:120
 print_address_description mm/kasan/report.c:408 [inline]
 print_report+0xb4/0x290 mm/kasan/report.c:521
 kasan_report+0x118/0x150 mm/kasan/report.c:634
 ocfs2_find_victim_chain fs/ocfs2/suballoc.c:1447 [inline]
 ocfs2_claim_suballoc_bits+0x8b2/0x2450 fs/ocfs2/suballoc.c:1996
 ocfs2_claim_metadata+0x178/0x4c0 fs/ocfs2/suballoc.c:2082
 ocfs2_create_refcount_tree+0x54f/0x1250 fs/ocfs2/refcounttree.c:591
 ocfs2_reflink_remap_blocks+0x2ea/0x1930 fs/ocfs2/refcounttree.c:4646
 ocfs2_remap_file_range+0x4b7/0x730 fs/ocfs2/file.c:2740
 vfs_copy_file_range+0xd53/0x1310 fs/read_write.c:1589
 __do_sys_copy_file_range fs/read_write.c:1675 [inline]
 __se_sys_copy_file_range+0x319/0x460 fs/read_write.c:1642
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0xf6/0x210 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7fc48d579e79
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:00007fc48e289038 EFLAGS: 00000246 ORIG_RAX: 0000000000000146
RAX: ffffffffffffffda RBX: 00007fc48d715f80 RCX: 00007fc48d579e79
RDX: 0000000000000004 RSI: 0000000000000000 RDI: 0000000000000006
RBP: 00007fc48d5e7916 R08: 0000000000000006 R09: 0000000000000000
R10: 00000000200000c0 R11: 0000000000000246 R12: 0000000000000000
R13: 0000000000000000 R14: 00007fc48d715f80 R15: 00007fff5e2f2e78
 </TASK>

The buggy address belongs to the physical page:
page: refcount:0 mapcount:0 mapping:0000000000000000 index:0x5f pfn:0x5663b
flags: 0x4fff00000000000(node=1|zone=1|lastcpupid=0x7ff)
raw: 04fff00000000000 ffffea0001599008 ffffea00015990c8 0000000000000000
raw: 000000000000005f 0000000000000000 00000000ffffffff 0000000000000000
page dumped because: kasan: bad access detected
page_owner tracks the page as freed
page last allocated via order 0, migratetype Movable, gfp_mask 0x140cca(GFP_HIGHUSER_MOVABLE|__GFP_COMP), pid 5857, tgid 5857 (rm), ts 138838352422, free_ts 138849693670
 set_page_owner include/linux/page_owner.h:32 [inline]
 post_alloc_hook+0x1d8/0x230 mm/page_alloc.c:1718
 prep_new_page mm/page_alloc.c:1726 [inline]
 get_page_from_freelist+0x21ce/0x22b0 mm/page_alloc.c:3688
 __alloc_frozen_pages_noprof+0x181/0x370 mm/page_alloc.c:4970
 alloc_pages_mpol+0x232/0x4a0 mm/mempolicy.c:2301
 folio_alloc_mpol_noprof mm/mempolicy.c:2320 [inline]
 vma_alloc_folio_noprof+0xe4/0x200 mm/mempolicy.c:2355
 folio_prealloc+0x30/0x180 mm/memory.c:-1
 wp_page_copy mm/memory.c:3478 [inline]
 do_wp_page+0x123a/0x5760 mm/memory.c:3939
 handle_pte_fault mm/memory.c:6013 [inline]
 __handle_mm_fault+0x1028/0x5380 mm/memory.c:6140
 handle_mm_fault+0x3f6/0x8c0 mm/memory.c:6309
 do_user_addr_fault+0xa81/0x1390 arch/x86/mm/fault.c:1337
 handle_page_fault arch/x86/mm/fault.c:1480 [inline]
 exc_page_fault+0x68/0x110 arch/x86/mm/fault.c:1538
 asm_exc_page_fault+0x26/0x30 arch/x86/include/asm/idtentry.h:623
page last free pid 5857 tgid 5857 stack trace:
 reset_page_owner include/linux/page_owner.h:25 [inline]
 free_pages_prepare mm/page_alloc.c:1262 [inline]
 free_unref_folios+0xb81/0x14a0 mm/page_alloc.c:2782
 folios_put_refs+0x559/0x640 mm/swap.c:992
 free_pages_and_swap_cache+0x277/0x520 mm/swap_state.c:267
 __tlb_batch_free_encoded_pages mm/mmu_gather.c:136 [inline]
 tlb_batch_pages_flush mm/mmu_gather.c:149 [inline]
 tlb_flush_mmu_free mm/mmu_gather.c:397 [inline]
 tlb_flush_mmu+0x3a0/0x680 mm/mmu_gather.c:404
 tlb_finish_mmu+0xc3/0x1d0 mm/mmu_gather.c:496
 exit_mmap+0x474/0xba0 mm/mmap.c:1297
 __mmput+0x118/0x420 kernel/fork.c:1379
 exit_mm+0x1da/0x2c0 kernel/exit.c:589
 do_exit+0x859/0x2550 kernel/exit.c:940
 do_group_exit+0x21c/0x2d0 kernel/exit.c:1102
 __do_sys_exit_group kernel/exit.c:1113 [inline]
 __se_sys_exit_group kernel/exit.c:1111 [inline]
 __x64_sys_exit_group+0x3f/0x40 kernel/exit.c:1111
 x64_sys_call+0x21ba/0x21c0 arch/x86/include/generated/asm/syscalls_64.h:232
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0xf6/0x210 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

Memory state around the buggy address:
 ffff88805663af00: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
 ffff88805663af80: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
>ffff88805663b000: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
                   ^
 ffff88805663b080: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
 ffff88805663b100: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
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