EXT4-fs error (device loop0): ext4_mb_generate_buddy:1306: group 0, block bitmap and bg descriptor inconsistent: 25 vs 4278190105 free clusters
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kernel BUG at fs/ext4/inode.c:2810!
Oops: invalid opcode: 0000 [#1] SMP KASAN NOPTI
CPU: 0 UID: 0 PID: 5337 Comm: syz.0.0 Not tainted syzkaller #0 PREEMPT(full) 
Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.3-debian-1.16.3-2 04/01/2014
RIP: 0010:ext4_do_writepages+0x45f4/0x4600 fs/ext4/inode.c:2809
Code: c6 40 dd a3 8b e8 5c 71 a9 fe 90 0f 0b e8 84 11 44 ff 4c 89 f7 48 c7 c6 20 e2 a3 8b e8 45 71 a9 fe 90 0f 0b e8 6d 11 44 ff 90 <0f> 0b 66 2e 0f 1f 84 00 00 00 00 00 90 90 90 90 90 90 90 90 90 90
RSP: 0018:ffffc9000db1f300 EFLAGS: 00010293
RAX: ffffffff827e9713 RBX: 0000006a10000000 RCX: ffff8880003ba4c0
RDX: 0000000000000000 RSI: 0000004000000000 RDI: 0000000000000000
RBP: ffffc9000db1f710 R08: ffff888012a51397 R09: 1ffff1100254a272
R10: dffffc0000000000 R11: ffffed100254a273 R12: dffffc0000000000
R13: 0000000000000001 R14: 0000004000000000 R15: 1ffff110087338c7
FS:  0000000000000000(0000) GS:ffff88808cf1d000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007fd4dfddfe9c CR3: 0000000044551000 CR4: 0000000000352ef0
Call Trace:
 <TASK>
 ext4_writepages+0x241/0x3b0 fs/ext4/inode.c:3026
 do_writepages+0x32e/0x550 mm/page-writeback.c:2598
 filemap_writeback mm/filemap.c:387 [inline]
 filemap_flush_range mm/filemap.c:436 [inline]
 filemap_flush+0x1e1/0x2e0 mm/filemap.c:451
 ext4_release_file+0x82/0x310 fs/ext4/file.c:169
 __fput+0x44f/0xa70 fs/file_table.c:468
 task_work_run+0x1d9/0x270 kernel/task_work.c:233
 exit_task_work include/linux/task_work.h:40 [inline]
 do_exit+0x69b/0x2310 kernel/exit.c:971
 do_group_exit+0x21b/0x2d0 kernel/exit.c:1112
 __do_sys_exit_group kernel/exit.c:1123 [inline]
 __se_sys_exit_group kernel/exit.c:1121 [inline]
 __x64_sys_exit_group+0x3f/0x40 kernel/exit.c:1121
 x64_sys_call+0x2210/0x2210 arch/x86/include/generated/asm/syscalls_64.h:232
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0xe2/0xf80 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f6ead79acb9
Code: Unable to access opcode bytes at 0x7f6ead79ac8f.
RSP: 002b:00007ffe69e6d4b8 EFLAGS: 00000246 ORIG_RAX: 00000000000000e7
RAX: ffffffffffffffda RBX: 000000000000000b RCX: 00007f6ead79acb9
RDX: 0000000000000001 RSI: 0000000000000000 RDI: 000000000000000b
RBP: 0000000000001c5a R08: 00007ffe69e6e077 R09: 000000000000000b
R10: 00007f6eada15fa0 R11: 0000000000000246 R12: 0000000000000003
R13: 00007f6eada1627c R14: 00007f6eada16278 R15: 00007f6eada16270
 </TASK>
Modules linked in:
---[ end trace 0000000000000000 ]---
RIP: 0010:ext4_do_writepages+0x45f4/0x4600 fs/ext4/inode.c:2809
Code: c6 40 dd a3 8b e8 5c 71 a9 fe 90 0f 0b e8 84 11 44 ff 4c 89 f7 48 c7 c6 20 e2 a3 8b e8 45 71 a9 fe 90 0f 0b e8 6d 11 44 ff 90 <0f> 0b 66 2e 0f 1f 84 00 00 00 00 00 90 90 90 90 90 90 90 90 90 90
RSP: 0018:ffffc9000db1f300 EFLAGS: 00010293
RAX: ffffffff827e9713 RBX: 0000006a10000000 RCX: ffff8880003ba4c0
RDX: 0000000000000000 RSI: 0000004000000000 RDI: 0000000000000000
RBP: ffffc9000db1f710 R08: ffff888012a51397 R09: 1ffff1100254a272
R10: dffffc0000000000 R11: ffffed100254a273 R12: dffffc0000000000
R13: 0000000000000001 R14: 0000004000000000 R15: 1ffff110087338c7
FS:  0000000000000000(0000) GS:ffff88808cf1d000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000556298fc9168 CR3: 000000001173c000 CR4: 0000000000352ef0