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kernel BUG at fs/ext4/inode.c:2630!
invalid opcode: 0000 [#1] PREEMPT SMP KASAN
Dumping ftrace buffer:
   (ftrace buffer empty)
Modules linked in:
CPU: 0 PID: 4270 Comm: syz-executor172 Not tainted 4.9.100-ge14d1a3 #27
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
task: ffff8801d90dc800 task.stack: ffff8801b6350000
RIP: 0010:[<ffffffff8173cde8>]  [<ffffffff8173cde8>] mpage_prepare_extent_to_map+0x7f8/0xa40 fs/ext4/inode.c:2630
RSP: 0018:ffff8801b63573c0  EFLAGS: 00010293
RAX: ffff8801d90dc800 RBX: ffffea0006f19a80 RCX: 0000000000000000
RDX: 0000000000000000 RSI: ffffffff8173cde8 RDI: ffffea0006f19a88
RBP: ffff8801b6357588 R08: ffff8801d90dd138 R09: 0000000000000001
R10: 0000000000000000 R11: 1ffff1003b21ba22 R12: 0000000000000009
R13: 0000000000000000 R14: ffff8801b63576f0 R15: dffffc0000000000
FS:  0000000000000000(0000) GS:ffff8801db200000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f9f07c21e78 CR3: 000000000461e000 CR4: 00000000001606f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Stack:
 1ffff10036c6ae88 ffff8801b63576f8 ffff8801b6357460 ffff8801b6357700
 00000000d90dd0c0 ffff8801b6f37538 000000010000000c 7fffffffffffffff
 ffff8801b63574a0 ffff8801b6357708 ffffea0006f19a90 ffffed0036c6aedf
Call Trace:
 [<ffffffff8174dcb9>] ext4_writepages+0xdb9/0x2e50 fs/ext4/inode.c:2792
 [<ffffffff8145ca7f>] do_writepages+0xef/0x1d0 mm/page-writeback.c:2347
 [<ffffffff8143aae3>] __filemap_fdatawrite_range+0x1b3/0x250 mm/filemap.c:390
 [<ffffffff8143ad03>] __filemap_fdatawrite mm/filemap.c:398 [inline]
 [<ffffffff8143ad03>] filemap_flush+0x23/0x30 mm/filemap.c:423
 [<ffffffff817431b9>] ext4_alloc_da_blocks+0xd9/0x330 fs/ext4/inode.c:3169
 [<ffffffff8172921f>] ext4_release_file+0x1ff/0x2e0 fs/ext4/file.c:42
 [<ffffffff81575a33>] __fput+0x263/0x700 fs/file_table.c:208
 [<ffffffff81575f55>] ____fput+0x15/0x20 fs/file_table.c:244
 [<ffffffff8119603c>] task_work_run+0x10c/0x180 kernel/task_work.c:116
 [<ffffffff8113ec91>] exit_task_work include/linux/task_work.h:21 [inline]
 [<ffffffff8113ec91>] do_exit+0x9e1/0x27c0 kernel/exit.c:837
 [<ffffffff81144d91>] do_group_exit+0x111/0x340 kernel/exit.c:941
 [<ffffffff81167b8f>] get_signal+0x4cf/0x1450 kernel/signal.c:2317
 [<ffffffff810524d7>] do_signal+0x87/0x19f0 arch/x86/kernel/signal.c:807
 [<ffffffff81005581>] exit_to_usermode_loop+0xe1/0x120 arch/x86/entry/common.c:157
 [<ffffffff810064d4>] prepare_exit_to_usermode arch/x86/entry/common.c:191 [inline]
 [<ffffffff810064d4>] syscall_return_slowpath arch/x86/entry/common.c:260 [inline]
 [<ffffffff810064d4>] do_syscall_64+0x364/0x490 arch/x86/entry/common.c:287
 [<ffffffff839f4613>] entry_SYSCALL_64_after_swapgs+0x5d/0xdb
Code: ff 48 8b 75 d0 65 48 33 34 25 28 00 00 00 0f 85 50 02 00 00 48 81 c4 a0 01 00 00 5b 41 5c 41 5d 41 5e 41 5f 5d c3 e8 18 fc c1 ff <0f> 0b e8 11 fc c1 ff 8b 95 18 ff ff ff 85 d2 75 7a e8 02 fc c1 
RIP  [<ffffffff8173cde8>] mpage_prepare_extent_to_map+0x7f8/0xa40 fs/ext4/inode.c:2630
 RSP <ffff8801b63573c0>
---[ end trace d5cdce8e0c2c007b ]---