------------[ cut here ]------------
kernel BUG at fs/f2fs/data.c:356!
Oops: invalid opcode: 0000 [#1] SMP KASAN NOPTI
CPU: 0 UID: 0 PID: 3403 Comm: kworker/u4:17 Not tainted syzkaller #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
Workqueue: loop0 loop_rootcg_workfn
RIP: 0010:f2fs_write_end_io+0xb52/0xb60 fs/f2fs/data.c:355
Code: e8 73 5c 11 fe e9 91 f6 ff ff 89 d9 80 e1 07 38 c1 0f 8c e3 f6 ff ff 48 89 df e8 e9 5c 11 fe e9 d6 f6 ff ff e8 ff d9 a9 fd 90 <0f> 0b 66 66 66 2e 0f 1f 84 00 00 00 00 00 90 90 90 90 90 90 90 90
RSP: 0018:ffffc9000d967438 EFLAGS: 00010093
RAX: ffffffff84178001 RBX: 0000000000000000 RCX: ffff88800038a4c0
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 000000000000000a
RBP: ffff888000ef6b40 R08: ffffea00014c42c7 R09: 1ffffd4000298858
R10: dffffc0000000000 R11: fffff94000298859 R12: 0000000000000006
R13: ffffea00014c42c0 R14: 000000000000000a R15: dffffc0000000000
FS:  0000000000000000(0000) GS:ffff88808d69f000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000200000005b00 CR3: 000000000dd3a000 CR4: 0000000000352ef0
Call Trace:
 <TASK>
 blk_update_request+0x57e/0xe60 block/blk-mq.c:1006
 blk_mq_end_request+0x3e/0x70 block/blk-mq.c:1168
 blk_flush_complete_seq+0x678/0xcc0 block/blk-flush.c:191
 flush_end_io+0xbaf/0xe60 block/blk-flush.c:250
 __blk_mq_end_request+0x46a/0x630 block/blk-mq.c:1158
 loop_handle_cmd drivers/block/loop.c:1944 [inline]
 loop_process_work+0xac3/0x10b0 drivers/block/loop.c:1962
 process_one_work kernel/workqueue.c:3257 [inline]
 process_scheduled_works+0xad1/0x1770 kernel/workqueue.c:3340
 worker_thread+0x8a0/0xda0 kernel/workqueue.c:3421
 kthread+0x711/0x8a0 kernel/kthread.c:463
 ret_from_fork+0x599/0xb30 arch/x86/kernel/process.c:158
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:246
 </TASK>
Modules linked in:
---[ end trace 0000000000000000 ]---
RIP: 0010:f2fs_write_end_io+0xb52/0xb60 fs/f2fs/data.c:355
Code: e8 73 5c 11 fe e9 91 f6 ff ff 89 d9 80 e1 07 38 c1 0f 8c e3 f6 ff ff 48 89 df e8 e9 5c 11 fe e9 d6 f6 ff ff e8 ff d9 a9 fd 90 <0f> 0b 66 66 66 2e 0f 1f 84 00 00 00 00 00 90 90 90 90 90 90 90 90
RSP: 0018:ffffc9000d967438 EFLAGS: 00010093
RAX: ffffffff84178001 RBX: 0000000000000000 RCX: ffff88800038a4c0
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 000000000000000a
RBP: ffff888000ef6b40 R08: ffffea00014c42c7 R09: 1ffffd4000298858
R10: dffffc0000000000 R11: fffff94000298859 R12: 0000000000000006
R13: ffffea00014c42c0 R14: 000000000000000a R15: dffffc0000000000
FS:  0000000000000000(0000) GS:ffff88808d69f000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000200000005b00 CR3: 000000000dd3a000 CR4: 0000000000352ef0