F2FS-fs (loop0): Found nat_bits in checkpoint
F2FS-fs (loop0): Start checkpoint disabled!
F2FS-fs (loop0): Mounted with checkpoint version = 48b305e6
------------[ cut here ]------------
kernel BUG at fs/f2fs/segment.c:3481!
invalid opcode: 0000 [#1] PREEMPT SMP KASAN
CPU: 0 PID: 20781 Comm: syz.0.4858 Not tainted 6.6.102-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/12/2025
RIP: 0010:f2fs_allocate_data_block+0x3f08/0x3f50 fs/f2fs/segment.c:3481
Code: 21 fe 48 8b 54 24 30 e9 c6 eb ff ff e8 21 51 ca fd 48 c7 c7 f0 cd 2f 8d 4c 89 f6 e8 d2 e5 95 00 e9 e2 eb ff ff e8 08 51 ca fd <0f> 0b e8 01 51 ca fd 0f 0b e8 fa 50 ca fd 0f 0b e8 f3 50 ca fd 0f
RSP: 0018:ffffc900035af410 EFLAGS: 00010283
RAX: ffffffff83bb3a18 RBX: 0000000000000200 RCX: 0000000000080000
RDX: ffffc9000cc79000 RSI: 0000000000030bc0 RDI: 0000000000030bc1
RBP: 0000000000000200 R08: ffff888024f2e05f R09: 1ffff110049e5c0b
R10: dffffc0000000000 R11: ffffed10049e5c0c R12: 1ffff920006b5ef8
R13: 0000000000000000 R14: 0000000000001e00 R15: dffffc0000000000
FS:  00007f1c7e3f66c0(0000) GS:ffff8880b8e00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007efce7fa9e9c CR3: 000000006cab2000 CR4: 00000000003506f0
Call Trace:
 <TASK>
 __allocate_data_block fs/f2fs/data.c:1421 [inline]
 f2fs_map_blocks+0x1301/0x3d60 fs/f2fs/data.c:1604
 f2fs_expand_inode_data+0x5c2/0x970 fs/f2fs/file.c:1837
 f2fs_fallocate+0x416/0x8a0 fs/f2fs/file.c:1940
 vfs_fallocate+0x58e/0x700 fs/open.c:324
 ioctl_preallocate fs/ioctl.c:291 [inline]
 file_ioctl fs/ioctl.c:-1 [inline]
 do_vfs_ioctl+0x1935/0x1bb0 fs/ioctl.c:850
 __do_sys_ioctl fs/ioctl.c:869 [inline]
 __se_sys_ioctl+0x83/0x170 fs/ioctl.c:857
 do_syscall_x64 arch/x86/entry/common.c:51 [inline]
 do_syscall_64+0x55/0xb0 arch/x86/entry/common.c:81
 entry_SYSCALL_64_after_hwframe+0x68/0xd2
RIP: 0033:0x7f1c8018ebe9
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:00007f1c7e3f6038 EFLAGS: 00000246 ORIG_RAX: 0000000000000010
RAX: ffffffffffffffda RBX: 00007f1c803b5fa0 RCX: 00007f1c8018ebe9
RDX: 00002000000000c0 RSI: 0000000040305828 RDI: 0000000000000004
RBP: 00007f1c80211e19 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f1c803b6038 R14: 00007f1c803b5fa0 R15: 00007ffda5c48b68
 </TASK>
Modules linked in:
---[ end trace 0000000000000000 ]---
RIP: 0010:f2fs_allocate_data_block+0x3f08/0x3f50 fs/f2fs/segment.c:3481
Code: 21 fe 48 8b 54 24 30 e9 c6 eb ff ff e8 21 51 ca fd 48 c7 c7 f0 cd 2f 8d 4c 89 f6 e8 d2 e5 95 00 e9 e2 eb ff ff e8 08 51 ca fd <0f> 0b e8 01 51 ca fd 0f 0b e8 fa 50 ca fd 0f 0b e8 f3 50 ca fd 0f
RSP: 0018:ffffc900035af410 EFLAGS: 00010283
RAX: ffffffff83bb3a18 RBX: 0000000000000200 RCX: 0000000000080000
RDX: ffffc9000cc79000 RSI: 0000000000030bc0 RDI: 0000000000030bc1
RBP: 0000000000000200 R08: ffff888024f2e05f R09: 1ffff110049e5c0b
R10: dffffc0000000000 R11: ffffed10049e5c0c R12: 1ffff920006b5ef8
R13: 0000000000000000 R14: 0000000000001e00 R15: dffffc0000000000
FS:  00007f1c7e3f66c0(0000) GS:ffff8880b8e00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007ffde7a74270 CR3: 000000006cab2000 CR4: 00000000003506f0