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ocfs2: Mounting device (7,0) on (node local, slot 0) with ordered data mode.
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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 ffff888071dd6000 by task syz-executor222/5825

CPU: 1 UID: 0 PID: 5825 Comm: syz-executor222 Not tainted 6.15.0-syzkaller-10402-g4cb6c8af8591 #0 PREEMPT(full) 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025
Call Trace:
 <TASK>
 dump_stack_lvl+0x189/0x250 lib/dump_stack.c:120
 print_address_description mm/kasan/report.c:408 [inline]
 print_report+0xd2/0x2b0 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_new_inode+0x332/0x7a0 fs/ocfs2/suballoc.c:2292
 ocfs2_mknod_locked+0x100/0x250 fs/ocfs2/namei.c:634
 ocfs2_mknod+0x10c7/0x2050 fs/ocfs2/namei.c:381
 ocfs2_mkdir+0x191/0x440 fs/ocfs2/namei.c:656
 vfs_mkdir+0x306/0x510 fs/namei.c:4366
 do_mkdirat+0x247/0x590 fs/namei.c:4399
 __do_sys_mkdirat fs/namei.c:4416 [inline]
 __se_sys_mkdirat fs/namei.c:4414 [inline]
 __x64_sys_mkdirat+0x87/0xa0 fs/namei.c:4414
 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: 0033:0x7fa471ea1f59
Code: 28 00 00 00 75 05 48 83 c4 28 c3 e8 f1 17 00 00 90 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 b8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007ffddee82338 EFLAGS: 00000246 ORIG_RAX: 0000000000000102
RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00007fa471ea1f59
RDX: 0000000000000000 RSI: 0000200000000040 RDI: 00000000ffffff9c
RBP: 0000000000000000 R08: 0000000000004457 R09: 00007ffddee82370
R10: 00007ffddee82200 R11: 0000000000000246 R12: 00007ffddee82370
R13: 00007ffddee825f8 R14: 431bde82d7b634db R15: 00007fa471eea03b
 </TASK>

The buggy address belongs to the physical page:
page: refcount:0 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x71dd6
flags: 0xfff00000000000(node=0|zone=1|lastcpupid=0x7ff)
raw: 00fff00000000000 ffffea0001c775c8 ffff8880b8741470 0000000000000000
raw: 0000000000000000 0000000000000000 00000000ffffffff 0000000000000000
page dumped because: kasan: bad access detected
page_owner tracks the page as freed
page last allocated via order 0, migratetype Unmovable, gfp_mask 0xcc0(GFP_KERNEL), pid 1, tgid 1 (swapper/0), ts 26692944343, free_ts 28787811005
 set_page_owner include/linux/page_owner.h:32 [inline]
 post_alloc_hook+0x240/0x2a0 mm/page_alloc.c:1710
 split_free_pages+0xd7/0x2f0 mm/page_alloc.c:6615
 alloc_contig_range_noprof+0xd29/0x1210 mm/page_alloc.c:6792
 __alloc_contig_pages mm/page_alloc.c:6822 [inline]
 alloc_contig_pages_noprof+0x47b/0x5a0 mm/page_alloc.c:6904
 debug_vm_pgtable_alloc_huge_page+0xb5/0x110 mm/debug_vm_pgtable.c:1084
 init_args+0x95f/0xd70 mm/debug_vm_pgtable.c:1266
 debug_vm_pgtable+0xc0/0x450 mm/debug_vm_pgtable.c:1304
 do_one_initcall+0x233/0x820 init/main.c:1257
 do_initcall_level+0x137/0x1f0 init/main.c:1319
 do_initcalls+0x69/0xd0 init/main.c:1335
 kernel_init_freeable+0x3d9/0x570 init/main.c:1567
 kernel_init+0x1d/0x1d0 init/main.c:1457
 ret_from_fork+0x3fc/0x770 arch/x86/kernel/process.c:148
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245
page last free pid 1 tgid 1 stack trace:
 reset_page_owner include/linux/page_owner.h:25 [inline]
 free_pages_prepare mm/page_alloc.c:1254 [inline]
 __free_frozen_pages+0xc65/0xe50 mm/page_alloc.c:2717
 __free_pages mm/page_alloc.c:5082 [inline]
 free_contig_range+0x1bd/0x4a0 mm/page_alloc.c:6938
 destroy_args+0x7e/0x5d0 mm/debug_vm_pgtable.c:1017
 debug_vm_pgtable+0x412/0x450 mm/debug_vm_pgtable.c:1397
 do_one_initcall+0x233/0x820 init/main.c:1257
 do_initcall_level+0x137/0x1f0 init/main.c:1319
 do_initcalls+0x69/0xd0 init/main.c:1335
 kernel_init_freeable+0x3d9/0x570 init/main.c:1567
 kernel_init+0x1d/0x1d0 init/main.c:1457
 ret_from_fork+0x3fc/0x770 arch/x86/kernel/process.c:148
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245

Memory state around the buggy address:
 ffff888071dd5f00: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
 ffff888071dd5f80: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
>ffff888071dd6000: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
                   ^
 ffff888071dd6080: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
 ffff888071dd6100: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
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