------------[ cut here ]------------
kernel BUG at fs/ext4/mballoc.c:4781!
Oops: invalid opcode: 0000 [#1] SMP KASAN NOPTI
CPU: 0 UID: 0 PID: 44 Comm: kworker/u4:3 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+0x6bf/0x720 fs/ext4/mballoc.c:4781
Code: e8 26 83 a1 ff 48 ba 00 00 00 00 00 fc ff df e9 d7 fa ff ff e8 42 0b 2f ff 90 0f 0b e8 3a 0b 2f ff 90 0f 0b e8 32 0b 2f ff 90 <0f> 0b e8 2a 0b 2f ff 90 0f 0b 48 8b 0c 24 48 83 c1 54 80 e1 07 80
RSP: 0018:ffffc90000886540 EFLAGS: 00010293
RAX: ffffffff829917de RBX: 00000000ffffffeb RCX: ffff888031e02580
RDX: 0000000000000000 RSI: 000000000000001a RDI: 0000000000000005
RBP: 1ffff11008b236b5 R08: ffff88804591fc43 R09: 1ffff11008b23f88
R10: dffffc0000000000 R11: ffffed1008b23f89 R12: 0000000000000000
R13: 000000000000001a R14: 1ffff11008b23f8b R15: ffff88804591fc58
FS:  0000000000000000(0000) GS:ffff88808b0b4000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000056052e4c9168 CR3: 00000000139e2000 CR4: 0000000000352ef0
Call Trace:
 <TASK>
 ext4_mb_use_preallocated+0x638/0x13e0 fs/ext4/mballoc.c:4998
 ext4_mb_new_blocks+0x5a0/0x4530 fs/ext4/mballoc.c:6302
 ext4_alloc_branch fs/ext4/indirect.c:340 [inline]
 ext4_ind_map_blocks+0xe96/0x22a0 fs/ext4/indirect.c:635
 ext4_map_create_blocks+0xbb/0x530 fs/ext4/inode.c:632
 ext4_map_blocks+0x791/0x12c0 fs/ext4/inode.c:823
 mpage_map_one_extent fs/ext4/inode.c:2379 [inline]
 mpage_map_and_submit_extent fs/ext4/inode.c:2469 [inline]
 ext4_do_writepages+0x1901/0x4770 fs/ext4/inode.c:2938
 ext4_writepages+0x241/0x3b0 fs/ext4/inode.c:3032
 do_writepages+0x338/0x560 mm/page-writeback.c:2560
 __writeback_single_inode+0x136/0x1220 fs/fs-writeback.c:1803
 writeback_sb_inodes+0x9de/0x1b00 fs/fs-writeback.c:2114
 __writeback_inodes_wb+0x114/0x240 fs/fs-writeback.c:2190
 wb_writeback+0x42f/0xad0 fs/fs-writeback.c:2301
 wb_check_start_all fs/fs-writeback.c:2427 [inline]
 wb_do_writeback fs/fs-writeback.c:2474 [inline]
 wb_workfn+0x980/0x10f0 fs/fs-writeback.c:2512
 process_one_work kernel/workqueue.c:3396 [inline]
 process_scheduled_works+0xc3d/0x1630 kernel/workqueue.c:3479
 worker_thread+0xa47/0xfb0 kernel/workqueue.c:3560
 kthread+0x38b/0x480 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+0x6bf/0x720 fs/ext4/mballoc.c:4781
Code: e8 26 83 a1 ff 48 ba 00 00 00 00 00 fc ff df e9 d7 fa ff ff e8 42 0b 2f ff 90 0f 0b e8 3a 0b 2f ff 90 0f 0b e8 32 0b 2f ff 90 <0f> 0b e8 2a 0b 2f ff 90 0f 0b 48 8b 0c 24 48 83 c1 54 80 e1 07 80
RSP: 0018:ffffc90000886540 EFLAGS: 00010293
RAX: ffffffff829917de RBX: 00000000ffffffeb RCX: ffff888031e02580
RDX: 0000000000000000 RSI: 000000000000001a RDI: 0000000000000005
RBP: 1ffff11008b236b5 R08: ffff88804591fc43 R09: 1ffff11008b23f88
R10: dffffc0000000000 R11: ffffed1008b23f89 R12: 0000000000000000
R13: 000000000000001a R14: 1ffff11008b23f8b R15: ffff88804591fc58
FS:  0000000000000000(0000) GS:ffff88808b0b4000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000056052e4c9168 CR3: 00000000139e2000 CR4: 0000000000352ef0