------------[ cut here ]------------
kernel BUG at fs/ext4/mballoc.c:4780!
Oops: invalid opcode: 0000 [#1] SMP KASAN NOPTI
CPU: 0 UID: 0 PID: 68 Comm: kworker/u4:4 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
Workqueue: writeback wb_workfn (flush-7:0)
RIP: 0010:ext4_mb_use_inode_pa+0x6c1/0x720 fs/ext4/mballoc.c:4780
Code: e8 e4 91 a4 ff 48 ba 00 00 00 00 00 fc ff df e9 da fa ff ff e8 80 c8 37 ff 90 0f 0b e8 78 c8 37 ff 90 0f 0b e8 70 c8 37 ff 90 <0f> 0b e8 68 c8 37 ff 90 0f 0b 48 8b 0c 24 80 e1 07 80 c1 03 38 c1
RSP: 0018:ffffc90000ace528 EFLAGS: 00010293
RAX: ffffffff828e0670 RBX: 00000000ffffffcc RCX: ffff88800071ca00
RDX: 0000000000000000 RSI: 0000000000000054 RDI: 0000000000000020
RBP: 1ffff11008fd9329 R08: ffff888047ecdefb R09: 1ffff11008fd9bdf
R10: dffffc0000000000 R11: ffffed1008fd9be0 R12: 0000000000000000
R13: 0000000000000054 R14: 1ffff11008fd9be2 R15: ffff888047ecdf10
FS:  0000000000000000(0000) GS:ffff88808c882000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007fdeb4b4f000 CR3: 000000000e74a000 CR4: 0000000000352ef0
Call Trace:
 <TASK>
 ext4_mb_use_preallocated+0x660/0x13f0 fs/ext4/mballoc.c:4997
 ext4_mb_new_blocks+0x5e2/0x46c0 fs/ext4/mballoc.c:6301
 ext4_alloc_branch fs/ext4/indirect.c:340 [inline]
 ext4_ind_map_blocks+0xe96/0x2260 fs/ext4/indirect.c:635
 ext4_map_create_blocks+0xc1/0x540 fs/ext4/inode.c:633
 ext4_map_blocks+0x7cd/0x11d0 fs/ext4/inode.c:824
 mpage_map_one_extent fs/ext4/inode.c:2396 [inline]
 mpage_map_and_submit_extent fs/ext4/inode.c:2490 [inline]
 ext4_do_writepages+0x18f3/0x4670 fs/ext4/inode.c:2948
 ext4_writepages+0x241/0x3b0 fs/ext4/inode.c:3042
 do_writepages+0x32e/0x550 mm/page-writeback.c:2571
 __writeback_single_inode+0x133/0x10e0 fs/fs-writeback.c:1764
 writeback_sb_inodes+0x979/0x19d0 fs/fs-writeback.c:2056
 __writeback_inodes_wb+0x111/0x240 fs/fs-writeback.c:2132
 wb_writeback+0x459/0xb00 fs/fs-writeback.c:2243
 wb_check_start_all fs/fs-writeback.c:2369 [inline]
 wb_do_writeback fs/fs-writeback.c:2395 [inline]
 wb_workfn+0x921/0xf10 fs/fs-writeback.c:2428
 process_one_work kernel/workqueue.c:3302 [inline]
 process_scheduled_works+0xb5d/0x1860 kernel/workqueue.c:3385
 worker_thread+0xa53/0xfc0 kernel/workqueue.c:3466
 kthread+0x388/0x470 kernel/kthread.c:436
 ret_from_fork+0x514/0xb70 arch/x86/kernel/process.c:158
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245
 </TASK>
Modules linked in:
---[ end trace 0000000000000000 ]---
RIP: 0010:ext4_mb_use_inode_pa+0x6c1/0x720 fs/ext4/mballoc.c:4780
Code: e8 e4 91 a4 ff 48 ba 00 00 00 00 00 fc ff df e9 da fa ff ff e8 80 c8 37 ff 90 0f 0b e8 78 c8 37 ff 90 0f 0b e8 70 c8 37 ff 90 <0f> 0b e8 68 c8 37 ff 90 0f 0b 48 8b 0c 24 80 e1 07 80 c1 03 38 c1
RSP: 0018:ffffc90000ace528 EFLAGS: 00010293
RAX: ffffffff828e0670 RBX: 00000000ffffffcc RCX: ffff88800071ca00
RDX: 0000000000000000 RSI: 0000000000000054 RDI: 0000000000000020
RBP: 1ffff11008fd9329 R08: ffff888047ecdefb R09: 1ffff11008fd9bdf
R10: dffffc0000000000 R11: ffffed1008fd9be0 R12: 0000000000000000
R13: 0000000000000054 R14: 1ffff11008fd9be2 R15: ffff888047ecdf10
FS:  0000000000000000(0000) GS:ffff88808c882000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007fdeb4b4f000 CR3: 000000000e74a000 CR4: 0000000000352ef0