WARNING in blkdev_put

[syzbot]

Hello,

syzbot found the following crash on:

HEAD commit: b7d377b4 Merge 4.9.108 into android-4.9
git tree: android-4.9
console output: https://syzkaller.appspot.com/x/log.txt?x=1145fccf800000
kernel config: https://syzkaller.appspot.com/x/.config?x=a360a6f1c9995318
dashboard link: https://syzkaller.appspot.com/bug?extid=50a0edf1e2c7653f8e49
compiler: gcc (GCC) 8.0.1 20180413 (experimental)
syz repro: https://syzkaller.appspot.com/x/repro.syz?x=1437dfe8400000
C reproducer: https://syzkaller.appspot.com/x/repro.c?x=147785f8400000

IMPORTANT: if you fix the bug, please add the following tag to the commit:
Reported-by: syzbot+50a0ed...@syzkaller.appspotmail.com

loop7: p1 size 135963288 extends beyond EOD,
truncated
loop7: p2 start 1279850000 is beyond EOD,
truncated
------------[ cut here ]------------
WARNING: CPU: 1 PID: 8162 at fs/block_dev.c:1634 blkdev_put+0x4c8/0x560
fs/block_dev.c:1634
Kernel panic - not syncing: panic_on_warn set ...

CPU: 1 PID: 8162 Comm: syz-executor773 Not tainted 4.9.108-gb7d377b #47
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS
Google 01/01/2011
ffff8801c5c5f828
ffffffff81eb3e29 ffffffff83c48b40 00000000ffffffff 0000000000000000
0000000000000001 0000000000000662 ffff8801c5c5f8e8 ffffffff81421925
0000000041b58ab3 ffffffff843b9b78 ffffffff81421766Call Trace:
[<ffffffff81eb3e29>] __dump_stack lib/dump_stack.c:15 [inline]
[<ffffffff81eb3e29>] dump_stack+0xc1/0x128 lib/dump_stack.c:51
[<ffffffff81421925>] panic+0x1bf/0x3bc kernel/panic.c:179
[<ffffffff81421c11>] __warn.cold.9+0xc1/0x17f kernel/panic.c:542
[<ffffffff811367cc>] warn_slowpath_null+0x2c/0x40 kernel/panic.c:585
[<ffffffff816323b8>] blkdev_put+0x4c8/0x560 fs/block_dev.c:1634
[<ffffffff816324db>] blkdev_close+0x8b/0xb0 fs/block_dev.c:1670
[<ffffffff81578193>] __fput+0x263/0x700 fs/file_table.c:208
[<ffffffff815786b5>] ____fput+0x15/0x20 fs/file_table.c:244
[<ffffffff8119832c>] task_work_run+0x10c/0x180 kernel/task_work.c:116
[<ffffffff81140e41>] exit_task_work include/linux/task_work.h:21 [inline]
[<ffffffff81140e41>] do_exit+0x9e1/0x27c0 kernel/exit.c:837
[<ffffffff81146f41>] do_group_exit+0x111/0x340 kernel/exit.c:941
[<ffffffff81169d9f>] get_signal+0x4cf/0x1450 kernel/signal.c:2321
[<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
[<ffffffff839f99d3>] entry_SYSCALL_64_after_swapgs+0x5d/0xdb
Dumping ftrace buffer:
(ftrace buffer empty)
Kernel Offset: disabled
Rebooting in 86400 seconds..


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