------------[ cut here ]------------
kernel BUG at fs/ext4/extents.c:2153!
Oops: invalid opcode: 0000 [#1] SMP KASAN NOPTI
CPU: 0 UID: 0 PID: 127 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~bpo12+1 04/01/2014
Workqueue: writeback wb_workfn (flush-7:0)
RIP: 0010:ext4_ext_insert_extent+0x4ab7/0x4af0 fs/ext4/extents.c:2153
Code: 89 d9 80 e1 07 fe c1 38 c1 0f 8c a6 e7 ff ff 48 89 df e8 9c 4b b5 ff e9 99 e7 ff ff e8 12 12 4e ff 90 0f 0b e8 0a 12 4e ff 90 <0f> 0b e8 02 12 4e ff 90 0f 0b 89 d9 80 e1 07 80 c1 03 38 c1 0f 8c
RSP: 0018:ffffc900019de5e0 EFLAGS: 00010293
RAX: ffffffff82724186 RBX: 0000000000000000 RCX: ffff888000de8000
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000
RBP: ffffc900019de790 R08: ffff888012001bcf R09: 1ffff11002400379
R10: dffffc0000000000 R11: ffffed100240037a R12: 0000000000000000
R13: dffffc0000000000 R14: ffff88805214f620 R15: ffff888042dac000
FS:  0000000000000000(0000) GS:ffff88808d301000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000200000002000 CR3: 000000001c5a4000 CR4: 0000000000352ef0
Call Trace:
 <TASK>
 ext4_ext_map_blocks+0x1792/0x6ac0 fs/ext4/extents.c:4404
 ext4_map_create_blocks fs/ext4/inode.c:609 [inline]
 ext4_map_blocks+0x860/0x1740 fs/ext4/inode.c:811
 mpage_map_one_extent fs/ext4/inode.c:2374 [inline]
 mpage_map_and_submit_extent fs/ext4/inode.c:2468 [inline]
 ext4_do_writepages+0x1f88/0x4610 fs/ext4/inode.c:2931
 ext4_writepages+0x205/0x350 fs/ext4/inode.c:3025
 do_writepages+0x32e/0x550 mm/page-writeback.c:2604
 __writeback_single_inode+0x145/0xff0 fs/fs-writeback.c:1719
 writeback_sb_inodes+0x6c7/0x1010 fs/fs-writeback.c:2015
 __writeback_inodes_wb+0x111/0x240 fs/fs-writeback.c:2086
 wb_writeback+0x44f/0xaf0 fs/fs-writeback.c:2197
 wb_check_start_all fs/fs-writeback.c:2323 [inline]
 wb_do_writeback fs/fs-writeback.c:2349 [inline]
 wb_workfn+0x90b/0xef0 fs/fs-writeback.c:2382
 process_one_work kernel/workqueue.c:3263 [inline]
 process_scheduled_works+0xae1/0x17b0 kernel/workqueue.c:3346
 worker_thread+0x8a0/0xda0 kernel/workqueue.c:3427
 kthread+0x711/0x8a0 kernel/kthread.c:463
 ret_from_fork+0x4bc/0x870 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_ext_insert_extent+0x4ab7/0x4af0 fs/ext4/extents.c:2153
Code: 89 d9 80 e1 07 fe c1 38 c1 0f 8c a6 e7 ff ff 48 89 df e8 9c 4b b5 ff e9 99 e7 ff ff e8 12 12 4e ff 90 0f 0b e8 0a 12 4e ff 90 <0f> 0b e8 02 12 4e ff 90 0f 0b 89 d9 80 e1 07 80 c1 03 38 c1 0f 8c
RSP: 0018:ffffc900019de5e0 EFLAGS: 00010293
RAX: ffffffff82724186 RBX: 0000000000000000 RCX: ffff888000de8000
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000
RBP: ffffc900019de790 R08: ffff888012001bcf R09: 1ffff11002400379
R10: dffffc0000000000 R11: ffffed100240037a R12: 0000000000000000
R13: dffffc0000000000 R14: ffff88805214f620 R15: ffff888042dac000
FS:  0000000000000000(0000) GS:ffff88808d301000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007fa5fd8f3190 CR3: 00000000117ea000 CR4: 0000000000352ef0