WARNING in dio_complete

[syzbot]

Hello,

syzbot found the following crash on:

HEAD commit: 47350a9f ANDROID: x86_64_cuttlefish_defconfig: Enable lz4 ..
git tree: android-4.14
console output: https://syzkaller.appspot.com/x/log.txt?x=13b8f55a400000
kernel config: https://syzkaller.appspot.com/x/.config?x=10d236078f3378a3
dashboard link: https://syzkaller.appspot.com/bug?extid=b8169b73b542fac6e295
compiler: gcc (GCC) 8.0.1 20180413 (experimental)
syz repro: https://syzkaller.appspot.com/x/repro.syz?x=17d3e4ea400000
C reproducer: https://syzkaller.appspot.com/x/repro.c?x=11bc6f0e400000

IMPORTANT: if you fix the bug, please add the following tag to the commit:
Reported-by: syzbot+b8169b...@syzkaller.appspotmail.com

random: sshd: uninitialized urandom read (32 bytes read)
random: sshd: uninitialized urandom read (32 bytes read)
------------[ cut here ]------------
WARNING: CPU: 1 PID: 2022 at fs/direct-io.c:293 dio_complete+0x578/0x800
fs/direct-io.c:293
Kernel panic - not syncing: panic_on_warn set ...

CPU: 1 PID: 2022 Comm: syz-executor209 Not tainted 4.14.67+ #1
Call Trace:
__dump_stack lib/dump_stack.c:17 [inline]
dump_stack+0xb9/0x11b lib/dump_stack.c:53
panic+0x1bf/0x3a4 kernel/panic.c:181
__warn.cold.7+0x148/0x185 kernel/panic.c:542
report_bug+0x1f7/0x26c lib/bug.c:186
fixup_bug arch/x86/kernel/traps.c:177 [inline]
do_error_trap+0x1ba/0x2c0 arch/x86/kernel/traps.c:295
invalid_op+0x18/0x40 arch/x86/entry/entry_64.S:944
RIP: 0010:dio_complete+0x578/0x800 fs/direct-io.c:293
RSP: 0018:ffff8801bf7af070 EFLAGS: 00010297
RAX: ffff8801bf25af00 RBX: ffff8801c92d7a80 RCX: 0000000000000000
RDX: 0000000000000000 RSI: 0000000000000000 RDI: ffff8801bf25af24
RBP: 0000000000010000 R08: 1ffff1003a26b000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000000 R12: ffff8801c3c854d8
R13: 0000000000010000 R14: 0000000000000002 R15: ffff8801c92d7b18
do_blockdev_direct_IO fs/direct-io.c:1373 [inline]
__blockdev_direct_IO+0x7614/0xc4e0 fs/direct-io.c:1399
ext4_direct_IO_write fs/ext4/inode.c:3705 [inline]
ext4_direct_IO+0x905/0x27f0 fs/ext4/inode.c:3858
generic_file_direct_write+0x225/0x430 mm/filemap.c:2940
__generic_file_write_iter+0x213/0x540 mm/filemap.c:3119
ext4_file_write_iter+0x4f6/0xe20 fs/ext4/file.c:264
call_write_iter include/linux/fs.h:1782 [inline]
do_iter_readv_writev+0x3a4/0x560 fs/read_write.c:678
do_iter_write+0x156/0x530 fs/read_write.c:957
vfs_iter_write+0x70/0xa0 fs/read_write.c:970
iter_file_splice_write+0x5b4/0xab0 fs/splice.c:749
do_splice_from fs/splice.c:851 [inline]
direct_splice_actor+0x116/0x160 fs/splice.c:1018
splice_direct_to_actor+0x28c/0x750 fs/splice.c:973
do_splice_direct+0x17b/0x220 fs/splice.c:1061
do_sendfile+0x4a1/0xb50 fs/read_write.c:1438
SYSC_sendfile64 fs/read_write.c:1493 [inline]
SyS_sendfile64+0xab/0x140 fs/read_write.c:1485
do_syscall_64+0x19b/0x4b0 arch/x86/entry/common.c:289
entry_SYSCALL_64_after_hwframe+0x42/0xb7
RIP: 0033:0x4464d9
RSP: 002b:00007fdfb821ed18 EFLAGS: 00000297 ORIG_RAX: 0000000000000028
RAX: ffffffffffffffda RBX: 00000000006dbc48 RCX: 00000000004464d9
RDX: 0000000020d83ff8 RSI: 000000000000000a RDI: 0000000000000008
RBP: 00000000006dbc40 R08: 65732f636f72702f R09: 65732f636f72702f
R10: 00008000fffffffe R11: 0000000000000297 R12: 00000000006dbc4c
R13: 00007fdfb821ed20 R14: 0000000000000000 R15: 00000000006dbd4c
Dumping ftrace buffer:
(ftrace buffer empty)
Kernel Offset: 0x2ac00000 from 0xffffffff81000000 (relocation range:
0xffffffff80000000-0xffffffffbfffffff)
Rebooting in 86400 seconds..


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