syzbot

EXT4-fs error (device loop0): ext4_mb_generate_buddy:1314: group 0, block bitmap and bg descriptor inconsistent: 25 vs 150994969 free clusters
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kernel BUG at fs/ext4/inode.c:2825!
Oops: invalid opcode: 0000 [#1] SMP KASAN NOPTI
CPU: 0 UID: 0 PID: 5985 Comm: syz.0.36 Not tainted syzkaller #0 PREEMPT(full) 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/09/2026
RIP: 0010:ext4_do_writepages+0x2ddf/0x3ed0 fs/ext4/inode.c:2825
Code: a5 10 ff ff ff 48 c1 ea 03 80 3c 02 00 0f 84 fa e7 ff ff 48 8b bd 28 ff ff ff e8 8c 19 a4 ff e9 e9 e7 ff ff e8 c2 21 37 ff 90 <0f> 0b e8 ba 21 37 ff 89 9d f8 fe ff ff 44 0f b6 ad a3 fe ff ff e9
RSP: 0018:ffffc900025d7760 EFLAGS: 00010293
RAX: 0000000000000000 RBX: ffff888071c1f070 RCX: ffffffff82d22f21
RDX: ffff888034175d00 RSI: ffffffff82d24b9e RDI: ffff888034175d00
RBP: ffffc900025d7930 R08: 0000000000000007 R09: 0000000000000000
R10: 0000004000000000 R11: 0000000000000080 R12: 0000000000000001
R13: ffff888071c1f258 R14: 1ffff920004baf0c R15: ffffc900025d7978
FS:  00005555950bf500(0000) GS:ffff88812437d000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000200000000660 CR3: 000000002c007000 CR4: 0000000000350ef0
Call Trace:
 <TASK>
 ext4_writepages+0x347/0x750 fs/ext4/inode.c:3042
 do_writepages+0x278/0x600 mm/page-writeback.c:2571
 filemap_writeback+0x22d/0x2e0 mm/filemap.c:388
 ext4_alloc_da_blocks+0x213/0x2c0 fs/ext4/inode.c:3353
 ext4_release_file+0x17c/0x370 fs/ext4/file.c:169
 __fput+0x3ff/0xb50 fs/file_table.c:512
 task_work_run+0x150/0x240 kernel/task_work.c:233
 resume_user_mode_work include/linux/resume_user_mode.h:50 [inline]
 __exit_to_user_mode_loop kernel/entry/common.c:70 [inline]
 exit_to_user_mode_loop+0x1d8/0x6f0 kernel/entry/common.c:101
 __exit_to_user_mode_prepare include/linux/irq-entry-common.h:207 [inline]
 syscall_exit_to_user_mode_prepare include/linux/irq-entry-common.h:230 [inline]
 syscall_exit_to_user_mode include/linux/entry-common.h:318 [inline]
 do_syscall_64+0x666/0x870 arch/x86/entry/syscall_64.c:100
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f937fb9ce59
Code: ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 44 00 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 e8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007ffe59640cf8 EFLAGS: 00000246 ORIG_RAX: 00000000000001b4
RAX: 0000000000000000 RBX: 00007ffe59640de0 RCX: 00007f937fb9ce59
RDX: 0000000000000000 RSI: 000000000000001e RDI: 0000000000000003
RBP: 0000000000013a3b R08: 0000000000000001 R09: 0000000000000000
R10: 0000001b2c620000 R11: 0000000000000246 R12: 00007ffe59640e20
R13: 00007f937fe15fac R14: 0000000000013abb R15: 00007f937fe15fa0
 </TASK>
Modules linked in:
---[ end trace 0000000000000000 ]---
RIP: 0010:ext4_do_writepages+0x2ddf/0x3ed0 fs/ext4/inode.c:2825
Code: a5 10 ff ff ff 48 c1 ea 03 80 3c 02 00 0f 84 fa e7 ff ff 48 8b bd 28 ff ff ff e8 8c 19 a4 ff e9 e9 e7 ff ff e8 c2 21 37 ff 90 <0f> 0b e8 ba 21 37 ff 89 9d f8 fe ff ff 44 0f b6 ad a3 fe ff ff e9
RSP: 0018:ffffc900025d7760 EFLAGS: 00010293
RAX: 0000000000000000 RBX: ffff888071c1f070 RCX: ffffffff82d22f21
RDX: ffff888034175d00 RSI: ffffffff82d24b9e RDI: ffff888034175d00
RBP: ffffc900025d7930 R08: 0000000000000007 R09: 0000000000000000
R10: 0000004000000000 R11: 0000000000000080 R12: 0000000000000001
R13: ffff888071c1f258 R14: 1ffff920004baf0c R15: ffffc900025d7978
FS:  00005555950bf500(0000) GS:ffff88812437d000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000200000000660 CR3: 000000002c007000 CR4: 0000000000350ef0