WARNING in ext4_dio_get_block_overwrite

[syzbot]

Hello,

syzbot found the following crash on:

HEAD commit: c6db52a8 Linux 4.14.183
git tree: linux-4.14.y
console output: https://syzkaller.appspot.com/x/log.txt?x=171feea6100000
kernel config: https://syzkaller.appspot.com/x/.config?x=98bbe4d18401ff4
dashboard link: https://syzkaller.appspot.com/bug?extid=b09c426cd5cc83e80118
compiler: gcc (GCC) 9.0.0 20181231 (experimental)

Unfortunately, I don't have any reproducer for this crash yet.

IMPORTANT: if you fix the bug, please add the following tag to the commit:
Reported-by: syzbot+b09c42...@syzkaller.appspotmail.com

netlink: 24 bytes leftover after parsing attributes in process `syz-executor.4'.
netlink: 24 bytes leftover after parsing attributes in process `syz-executor.0'.
------------[ cut here ]------------
WARNING: CPU: 1 PID: 22242 at fs/ext4/inode.c:963 ext4_dio_get_block_overwrite fs/ext4/inode.c:963 [inline]
WARNING: CPU: 1 PID: 22242 at fs/ext4/inode.c:963 ext4_dio_get_block_overwrite+0x8d/0xc0 fs/ext4/inode.c:948
Kernel panic - not syncing: panic_on_warn set ...

CPU: 1 PID: 22242 Comm: syz-executor.4 Not tainted 4.14.183-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Call Trace:
__dump_stack lib/dump_stack.c:17 [inline]
dump_stack+0x1b2/0x283 lib/dump_stack.c:58
panic+0x1f9/0x42d kernel/panic.c:183
__warn.cold+0x2f/0x30 kernel/panic.c:547
report_bug+0x20a/0x248 lib/bug.c:186
fixup_bug arch/x86/kernel/traps.c:177 [inline]
fixup_bug arch/x86/kernel/traps.c:172 [inline]
do_error_trap+0x195/0x2d0 arch/x86/kernel/traps.c:295
invalid_op+0x1b/0x40 arch/x86/entry/entry_64.S:964
RIP: 0010:ext4_dio_get_block_overwrite fs/ext4/inode.c:963 [inline]
RIP: 0010:ext4_dio_get_block_overwrite+0x8d/0xc0 fs/ext4/inode.c:948
RSP: 0018:ffff88804ccf7308 EFLAGS: 00010246
RAX: 0000000000040000 RBX: ffff88804ccf74b0 RCX: ffffc9000a525000
RDX: 0000000000040000 RSI: ffffffff81be706d RDI: ffff888215f28618
RBP: 000000000000007a R08: 0000000000000001 R09: 0000000000000001
R10: ffff88804301a8f0 R11: ffff88804301a040 R12: 0000000000000000
R13: ffff88804301a040 R14: 000000000000007a R15: ffff88801ad715c0
get_more_blocks fs/direct-io.c:718 [inline]
do_direct_IO fs/direct-io.c:1003 [inline]
do_blockdev_direct_IO fs/direct-io.c:1336 [inline]
__blockdev_direct_IO+0x3103/0xe97c fs/direct-io.c:1422
ext4_direct_IO_write fs/ext4/inode.c:3716 [inline]
ext4_direct_IO+0xeb8/0x1970 fs/ext4/inode.c:3852
generic_file_direct_write+0x1df/0x420 mm/filemap.c:2950
__generic_file_write_iter+0x2a5/0x590 mm/filemap.c:3129
ext4_file_write_iter+0x279/0xd90 fs/ext4/file.c:270
call_write_iter include/linux/fs.h:1778 [inline]
do_iter_readv_writev+0x3df/0x600 fs/read_write.c:675
do_iter_write fs/read_write.c:954 [inline]
do_iter_write+0x152/0x550 fs/read_write.c:935
vfs_iter_write+0x70/0xa0 fs/read_write.c:967
iter_file_splice_write+0x52e/0xa10 fs/splice.c:749
do_splice_from fs/splice.c:851 [inline]
direct_splice_actor+0x115/0x160 fs/splice.c:1018
splice_direct_to_actor+0x27e/0x730 fs/splice.c:973
do_splice_direct+0x164/0x210 fs/splice.c:1061
do_sendfile+0x469/0xaf0 fs/read_write.c:1441
SYSC_sendfile64 fs/read_write.c:1502 [inline]
SyS_sendfile64+0xff/0x110 fs/read_write.c:1488
do_syscall_64+0x1d5/0x640 arch/x86/entry/common.c:292
entry_SYSCALL_64_after_hwframe+0x46/0xbb
RIP: 0033:0x45ca69
RSP: 002b:00007ff5ac387c78 EFLAGS: 00000246 ORIG_RAX: 0000000000000028
RAX: ffffffffffffffda RBX: 00000000004fc580 RCX: 000000000045ca69
RDX: 0000000000000000 RSI: 0000000000000009 RDI: 0000000000000003
RBP: 000000000078bf00 R08: 0000000000000000 R09: 0000000000000000
R10: 00008400fffffffa R11: 0000000000000246 R12: 00000000ffffffff
R13: 00000000000008dc R14: 00000000004cba56 R15: 00007ff5ac3886d4
Kernel Offset: disabled
Rebooting in 86400 seconds..


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[syzbot]

Auto-closing this bug as obsolete.
Crashes did not happen for a while, no reproducer and no activity.