possible deadlock in ovl_write_iter (3)

[syzbot]

Hello,

syzbot found the following issue on:

HEAD commit: c14d30dc Linux 4.19.139
git tree: linux-4.19.y
console output: https://syzkaller.appspot.com/x/log.txt?x=145ed7d6900000
kernel config: https://syzkaller.appspot.com/x/.config?x=93b261233af4719e
dashboard link: https://syzkaller.appspot.com/bug?extid=9356bcfc031708500480
compiler: gcc (GCC) 10.1.0-syz 20200507
syz repro: https://syzkaller.appspot.com/x/repro.syz?x=12eedb9a900000
C reproducer: https://syzkaller.appspot.com/x/repro.c?x=1602387a900000

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+9356bc...@syzkaller.appspotmail.com

overlayfs: upperdir is in-use as upperdir/workdir of another mount, mount with '-o index=off' to override exclusive upperdir protection.
overlayfs: upperdir is in-use as upperdir/workdir of another mount, mount with '-o index=off' to override exclusive upperdir protection.
======================================================
overlayfs: filesystem on './file0' not supported as upperdir
WARNING: possible circular locking dependency detected
4.19.139-syzkaller #0 Not tainted
------------------------------------------------------
syz-executor315/6483 is trying to acquire lock:
0000000017c973ad (&ovl_i_mutex_key[depth]){+.+.}, at: inode_lock include/linux/fs.h:748 [inline]
0000000017c973ad (&ovl_i_mutex_key[depth]){+.+.}, at: ovl_write_iter+0x148/0xb40 fs/overlayfs/file.c:270

but task is already holding lock:
00000000a0a2053c (&pipe->mutex/1){+.+.}, at: pipe_lock_nested fs/pipe.c:62 [inline]
00000000a0a2053c (&pipe->mutex/1){+.+.}, at: pipe_lock fs/pipe.c:70 [inline]
00000000a0a2053c (&pipe->mutex/1){+.+.}, at: pipe_wait+0x1bd/0x1e0 fs/pipe.c:118

which lock already depends on the new lock.


the existing dependency chain (in reverse order) is:

-> #2 (&pipe->mutex/1){+.+.}:
overlayfs: filesystem on './file0' not supported as upperdir
pipe_lock_nested fs/pipe.c:62 [inline]
pipe_lock+0x63/0x80 fs/pipe.c:70
iter_file_splice_write+0x183/0xbb0 fs/splice.c:700
do_splice_from fs/splice.c:852 [inline]
do_splice fs/splice.c:1154 [inline]
__do_sys_splice fs/splice.c:1428 [inline]
__se_sys_splice+0xfe7/0x16d0 fs/splice.c:1408
do_syscall_64+0xf9/0x620 arch/x86/entry/common.c:293
entry_SYSCALL_64_after_hwframe+0x49/0xbe

-> #1 (sb_writers#3){.+.+}:
sb_start_write include/linux/fs.h:1579 [inline]
mnt_want_write+0x3a/0xb0 fs/namespace.c:360
ovl_setattr+0xdd/0x920 fs/overlayfs/inode.c:30
notify_change+0x70b/0xfc0 fs/attr.c:334
do_truncate+0x134/0x1f0 fs/open.c:63
handle_truncate fs/namei.c:3009 [inline]
do_last fs/namei.c:3427 [inline]
path_openat+0x2308/0x2df0 fs/namei.c:3537
do_filp_open+0x18c/0x3f0 fs/namei.c:3567
do_sys_open+0x3b3/0x520 fs/open.c:1085
do_syscall_64+0xf9/0x620 arch/x86/entry/common.c:293
entry_SYSCALL_64_after_hwframe+0x49/0xbe

-> #0 (&ovl_i_mutex_key[depth]){+.+.}:
down_write+0x34/0x90 kernel/locking/rwsem.c:70
inode_lock include/linux/fs.h:748 [inline]
ovl_write_iter+0x148/0xb40 fs/overlayfs/file.c:270
call_write_iter include/linux/fs.h:1821 [inline]
new_sync_write fs/read_write.c:474 [inline]
__vfs_write+0x51b/0x770 fs/read_write.c:487
__kernel_write+0x109/0x370 fs/read_write.c:506
write_pipe_buf+0x153/0x1f0 fs/splice.c:798
splice_from_pipe_feed fs/splice.c:503 [inline]
__splice_from_pipe+0x389/0x800 fs/splice.c:627
splice_from_pipe fs/splice.c:662 [inline]
default_file_splice_write+0xd8/0x180 fs/splice.c:810
do_splice_from fs/splice.c:852 [inline]
do_splice fs/splice.c:1154 [inline]
__do_sys_splice fs/splice.c:1428 [inline]
__se_sys_splice+0xfe7/0x16d0 fs/splice.c:1408
do_syscall_64+0xf9/0x620 arch/x86/entry/common.c:293
entry_SYSCALL_64_after_hwframe+0x49/0xbe

other info that might help us debug this:

Chain exists of:
&ovl_i_mutex_key[depth] --> sb_writers#3 --> &pipe->mutex/1

Possible unsafe locking scenario:

CPU0 CPU1
---- ----
lock(&pipe->mutex/1);
lock(sb_writers#3);
lock(&pipe->mutex/1);
lock(&ovl_i_mutex_key[depth]);

*** DEADLOCK ***

2 locks held by syz-executor315/6483:
#0: 000000005c845a01 (sb_writers#13){.+.+}, at: file_start_write include/linux/fs.h:2776 [inline]
#0: 000000005c845a01 (sb_writers#13){.+.+}, at: do_splice fs/splice.c:1153 [inline]
#0: 000000005c845a01 (sb_writers#13){.+.+}, at: __do_sys_splice fs/splice.c:1428 [inline]
#0: 000000005c845a01 (sb_writers#13){.+.+}, at: __se_sys_splice+0x11de/0x16d0 fs/splice.c:1408
#1: 00000000a0a2053c (&pipe->mutex/1){+.+.}, at: pipe_lock_nested fs/pipe.c:62 [inline]
#1: 00000000a0a2053c (&pipe->mutex/1){+.+.}, at: pipe_lock fs/pipe.c:70 [inline]
#1: 00000000a0a2053c (&pipe->mutex/1){+.+.}, at: pipe_wait+0x1bd/0x1e0 fs/pipe.c:118

stack backtrace:
CPU: 1 PID: 6483 Comm: syz-executor315 Not tainted 4.19.139-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Call Trace:
__dump_stack lib/dump_stack.c:77 [inline]
dump_stack+0x1fc/0x2fe lib/dump_stack.c:118
print_circular_bug.constprop.0.cold+0x2d7/0x41e kernel/locking/lockdep.c:1221
check_prev_add kernel/locking/lockdep.c:1865 [inline]
check_prevs_add kernel/locking/lockdep.c:1978 [inline]
validate_chain kernel/locking/lockdep.c:2419 [inline]
__lock_acquire+0x30c9/0x3ff0 kernel/locking/lockdep.c:3415
lock_acquire+0x170/0x3c0 kernel/locking/lockdep.c:3907
down_write+0x34/0x90 kernel/locking/rwsem.c:70
inode_lock include/linux/fs.h:748 [inline]
ovl_write_iter+0x148/0xb40 fs/overlayfs/file.c:270
call_write_iter include/linux/fs.h:1821 [inline]
new_sync_write fs/read_write.c:474 [inline]
__vfs_write+0x51b/0x770 fs/read_write.c:487
__kernel_write+0x109/0x370 fs/read_write.c:506
write_pipe_buf+0x153/0x1f0 fs/splice.c:798
splice_from_pipe_feed fs/splice.c:503 [inline]
__splice_from_pipe+0x389/0x800 fs/splice.c:627
splice_from_pipe fs/splice.c:662 [inline]
default_file_splice_write+0xd8/0x180 fs/splice.c:810
do_splice_from fs/splice.c:852 [inline]
do_splice fs/splice.c:1154 [inline]
__do_sys_splice fs/splice.c:1428 [inline]
__se_sys_splice+0xfe7/0x16d0 fs/splice.c:1408
do_syscall_64+0xf9/0x620 arch/x86/entry/common.c:293
entry_SYSCALL_64_after_hwframe+0x49/0xbe
RIP: 0033:0x446a89
Code: e8 0c e8 ff ff 48 83 c4 18 c3 0f 1f 80 00 00 00 00 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 0f 83 db 06 fc ff c3 66 2e 0f 1f 84 00 00 00 00
RSP: 002b:00007f3ebcd4dda8 EFLAGS: 00000246 ORIG_RAX: 0000000000000113
RAX: ffffffffffffffda RBX: 00000000006dbc78 RCX: 0000000000446a89
RDX: 000000000000000a RSI: 0000000000000000 RDI: 0000000000000008
RBP: 00000000006dbc70 R08: 00000000088000cc R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 00000000006dbc7c
R13: 00007ffeeacba97f R14: 00007f3ebcd4e9c0 R15: 0000000000000001
overlayfs: filesystem on './file0' not supported as upperdir
overlayfs: failed to resolve './file0': -2
overlayfs: filesystem on './file0' not supported as upperdir
overlayfs: upperdir is in-use as upperdir/workdir of another mount, mount with '-o index=off' to override exclusive upperdir protection.
overlayfs: upperdir is in-use as upperdir/workdir of another mount, mount with '-o index=off' to override exclusive upperdir protection.
overlayfs: upperdir is in-use as upperdir/workdir of another mount, mount with '-o index=off' to override exclusive upperdir protection.
overlayfs: upperdir is in-use as upperdir/workdir of another mount, mount with '-o index=off' to override exclusive upperdir protection.
overlayfs: upperdir is in-use as upperdir/workdir of another mount, mount with '-o index=off' to override exclusive upperdir protection.
overlayfs: upperdir is in-use as upperdir/workdir of another mount, mount with '-o index=off' to override exclusive upperdir protection.
overlayfs: filesystem on './file0' not supported as upperdir
overlayfs: filesystem on './file0' not supported as upperdir
overlayfs: filesystem on './file0' not supported as upperdir
overlayfs: failed to resolve './file0': -2
overlayfs: filesystem on './file0' not supported as upperdir
overlayfs: filesystem on './file0' not supported as upperdir
overlayfs: upperdir is in-use as upperdir/workdir of another mount, mount with '-o index=off' to override exclusive upperdir protection.
overlayfs: upperdir is in-use as upperdir/workdir of another mount, mount with '-o index=off' to override exclusive upperdir protection.
overlayfs: upperdir is in-use as upperdir/workdir of another mount, mount with '-o index=off' to override exclusive upperdir protection.
overlayfs: upperdir is in-use as upperdir/workdir of another mount, mount with '-o index=off' to override exclusive upperdir protection.
overlayfs: upperdir is in-use as upperdir/workdir of another mount, mount with '-o index=off' to override exclusive upperdir protection.
overlayfs: upperdir is in-use as upperdir/workdir of another mount, mount with '-o index=off' to override exclusive upperdir protection.
overlayfs: filesystem on './file0' not supported as upperdir
overlayfs: filesystem on './file0' not supported as upperdir
overlayfs: filesystem on './file0' not supported as upperdir
overlayfs: filesystem on './file0' not supported as upperdir
overlayfs: upperdir is in-use as upperdir/workdir of another mount, mount with '-o index=off' to override exclusive upperdir protection.
overlayfs: upperdir is in-use as upperdir/workdir of another mount, mount with '-o index=off' to override exclusive upperdir protection.
overlayfs: upperdir is in-use as upperdir/workdir of another mount, mount with '-o index=off' to override exclusive upperdir protection.
overlayfs: upperdir is in-use as upperdir/workdir of another mount, mount with '-o index=off' to override exclusive upperdir protection.
overlayfs: upperdir is in-use as upperdir/workdir of another mount, mount with '-o index=off' to override exclusive upperdir protection.
overlayfs: upperdir is in-use as upperdir/workdir of another mount, mount with '-o index=off' to override exclusive upperdir protection.
overlayfs: filesystem on './file0' not supported as upperdir
overlayfs: failed to resolve './file0': -2
overlayfs: filesystem on './file0' not supported as upperdir
overlayfs: filesystem on './file0' not supported as upperdir
overlayfs: filesystem on './file0' not supported as upperdir
overlayfs: upperdir is in-use as upperdir/workdir of another mount, mount with '-o index=off' to override exclusive upperdir protection.
overlayfs: upperdir is in-use as upperdir/workdir of another mount, mount with '-o index=off' to override exclusive upperdir protection.
overlayfs: upperdir is in-use as upperdir/workdir of another mount, mount with '-o index=off' to override exclusive upperdir protection.
overlayfs: upperdir is in-use as upperdir/workdir of another mount, mount with '-o index=off' to override exclusive upperdir protection.
overlayfs: upperdir is in-use as upperdir/workdir of another mount, mount with '-o index=off' to override exclusive upperdir protection.
overlayfs: upperdir is in-use as upperdir/workdir of another mount, mount with '-o index=off' to override exclusive upperdir protection.
overlayfs: filesystem on './file0' not supported as upperdir
overlayfs: filesystem on './file0' not supported as upperdir
overlayfs: filesystem on './file0' not supported as upperdir
overlayfs: filesystem on './file0' not supported as upperdir
overlayfs: failed to resolve './file0': -2
overlayfs: upperdir is in-use as upperdir/workdir of another mount, mount with '-o index=off' to override exclusive upperdir protection.
overlayfs: upperdir is in-use as upperdir/workdir of another mount, mount with '-o index=off' to override exclusive upperdir protection.
overlayfs: upperdir is in-use as upperdir/workdir of another mount, mount with '-o index=off' to override exclusive upperdir protection.
overlayfs: upperdir is in-use as upperdir/workdir of another mount, mount with '-o index=off' to override exclusive upperdir protection.
overlayfs: upperdir is in-use as upperdir/workdir of another mount, mount with '-o index=off' to override exclusive upperdir protection.
overlayfs: filesystem on './file0' not supported as upperdir
overlayfs: upperdir is in-use as upperdir/workdir of another mount, mount with '-o index=off' to override exclusive upperdir protection.
overlayfs: filesystem on './file0' not supported as upperdir
overlayfs: filesystem on './file0' not supported as upperdir
overlayfs: filesystem on './file0' not supported as upperdir
overlayfs: filesystem on './file0' not supported as upperdir
overlayfs: filesystem on './file0' not supported as upperdir
overlayfs: upperdir is in-use as upperdir/workdir of another mount, mount with '-o index=off' to override exclusive upperdir protection.
overlayfs: upperdir is in-use as upperdir/workdir of another mount, mount with '-o index=off' to override exclusive upperdir protection.
overlayfs: upperdir is in-use as upperdir/workdir of another mount, mount with '-o index=off' to override exclusive upperdir protection.
overlayfs: upperdir is in-use as upperdir/workdir of another mount, mount with '-o index=off' to override exclusive upperdir protection.
overlayfs: upperdir is in-use as upperdir/workdir of another mount, mount with '-o index=off' to override exclusive upperdir protection.
overlayfs: filesystem on './file0' not supported as upperdir
overlayfs: filesystem on './file0' not supported as upperdir
overlayfs: filesystem on './file0' not supported as upperdir
overlayfs: upperdir is in-use as upperdir/workdir of another mount, mount with '-o index=off' to override exclusive upperdir protection.
overlayfs: filesystem on './file0' not supported as upperdir
overlayfs: filesystem on './file0' not supported as upperdir
overlayfs: upperdir is in-use as upperdir/workdir of another mount, mount with '-o index=off' to override exclusive upperdir protection.
overlayfs: upperdir is in-use as upperdir/workdir of another mount, mount with '-o index=off' to override exclusive upperdir protection.
overlayfs: upperdir is in-use as upperdir/workdir of another mount, mount with '-o index=off' to override exclusive upperdir protection.
overlayfs: upperdir is in-use as upperdir/workdir of another mount, mount with '-o index=off' to override exclusive upperdir protection.
overlayfs: filesystem on './file0' not supported as upperdir
overlayfs: upperdir is in-use as upperdir/workdir of another mount, mount with '-o index=off' to override exclusive upperdir protection.
overlayfs: filesystem on './file0' not supported as upperdir
overlayfs: filesystem on './file0' not supported as upperdir
overlayfs: upperdir is in-use as upperdir/workdir of another mount, mount with '-o index=off' to override exclusive upperdir protection.
overlayfs: filesystem on './file0' not supported as upperdir
overlayfs: filesystem on './file0' not supported as upperdir
overlayfs: upperdir is in-use as upperdir/workdir of another mount, mount with '-o index=off' to override exclusive upperdir protection.
overlayfs: upperdir is in-use as upperdir/workdir of another mount, mount with '-o index=off' to override exclusive upperdir protection.
overlayfs: upperdir is in-use as upperdir/workdir of another mount, mount with '-o index=off' to override exclusive upperdir protection.
overlayfs: upperdir is in-use as upperdir/workdir of another mount, mount with '-o index=off' to override exclusive upperdir protection.
overlayfs: filesystem on './file0' not supported as upperdir
overlayfs: filesystem on './file0' not supported as upperdir
overlayfs: filesystem on './file0' not supported as upperdir
overlayfs: upperdir is in-use as upperdir/workdir of another mount, mount with '-o index=off' to override exclusive upperdir protection.
overlayfs: upperdir is in-use as upperdir/workdir of another mount, mount with '-o index=off' to override exclusive upperdir protection.
overlayfs: filesystem on './file0' not supported as upperdir
overlayfs: upperdir is in-use as upperdir/workdir of another mount, mount with '-o index=off' to override exclusive upperdir protection.
overlayfs: filesystem on './file0' not supported as upperdir
overlayfs: upperdir is in-use as upperdir/workdir of another mount, mount with '-o index=off' to override exclusive upperdir protection.
overlayfs: upperdir is in-use as upperdir/workdir of another mount, mount with '-o index=off' to override exclusive upperdir protection.
overlayfs: upperdir is in-use as upperdir/workdir of another mount, mount with '-o index=off' to override exclusive upperdir protection.
overlayfs: filesystem on './file0' not supported as upperdir
overlayfs: filesystem on './file0' not supported as upperdir
overlayfs: filesystem on './file0' not supported as upperdir
overlayfs: filesystem on './file0' not supported as upperdir
overlayfs: upperdir is in-use as upperdir/workdir of another mount, mount with '-o index=off' to override exclusive upperdir protection.
overlayfs: upperdir is in-use as upperdir/workdir of another mount, mount with '-o index=off' to override exclusive upperdir protection.
overlayfs: filesystem on './file0' not supported as upperdir
overlayfs: upperdir is in-use as upperdir/workdir of another mount, mount with '-o index=off' to override exclusive upperdir protection.
overlayfs: filesystem on './file0' not supported as upperdir
overlayfs: upperdir is in-use as upperdir/workdir of another mount, mount with '-o index=off' to override exclusive upperdir protection.
overlayfs: upperdir is in-use as upperdir/workdir of another mount, mount with '-o index=off' to override exclusive upperdir protection.
overlayfs: upperdir is in-use as upperdir/workdir of another mount, mount with '-o index=off' to override exclusive upperdir protection.
overlayfs: failed to resolve './file0': -2
overlayfs: failed to resolve './file0': -2
overlayfs: upperdir is in-use as upperdir/workdir of another mount, mount with '-o index=off' to override exclusive upperdir protection.
overlayfs: filesystem on './file0' not supported as upperdir
overlayfs: filesystem on './file0' not supported as upperdir
overlayfs: upperdir is in-use as upperdir/workdir of another mount, mount with '-o index=off' to override exclusive upperdir protection.
overlayfs: filesystem on './file0' not supported as upperdir
overlayfs: upperdir is in-use as upperdir/workdir of another mount, mount with '-o index=off' to override exclusive upperdir protection.
overlayfs: upperdir is in-use as upperdir/workdir of another mount, mount with '-o index=off' to override exclusive upperdir protection.
overlayfs: upperdir is in-use as upperdir/workdir of another mount, mount with '-o index=off' to override exclusive upperdir protection.
overlayfs: upperdir is in-use as upperdir/workdir of another mount, mount with '-o index=off' to override exclusive upperdir protection.
overlayfs: filesystem on './file0' not supported as upperdir
overlayfs: upperdir is in-use as upperdir/workdir of another mount, mount with '-o index=off' to override exclusive upperdir protection.
overlayfs: filesystem on './file0' not supported as upperdir
overlayfs: filesystem on './file0' not supported as upperdir
overlayfs: upperdir is in-use as upperdir/workdir of another mount, mount with '-o index=off' to override exclusive upperdir protection.
overlayfs: filesystem on './file0' not supported as upperdir
overlayfs: filesystem on './file0' not supported as upperdir
overlayfs: upperdir is in-use as upperdir/workdir of another mount, mount with '-o index=off' to override exclusive upperdir protection.
overlayfs: upperdir is in-use as upperdir/workdir of another mount, mount with '-o index=off' to override exclusive upperdir protection.
overlayfs: upperdir is in-use as upperdir/workdir of another mount, mount with '-o index=off' to override exclusive upperdir protection.
overlayfs: upperdir is in-use as upperdir/workdir of another mount, mount with '-o index=off' to override exclusive upperdir protection.
overlayfs: filesystem on './file0' not supported as upperdir
overlayfs: filesystem on './file0' not supported as upperdir
overlayfs: upperdir is in-use as upperdir/workdir of another mount, mount with '-o index=off' to override exclusive upperdir protection.
overlayfs: upperdir is in-use as upperdir/workdir of another mount, mount with '-o index=off' to override exclusive upperdir protection.
overlayfs: filesystem on './file0' not supported as upperdir
overlayfs: upperdir is in-use as upperdir/workdir of another mount, mount with '-o index=off' to override exclusive upperdir protection.
overlayfs: upperdir is in-use as upperdir/workdir of another mount, mount with '-o index=off' to override exclusive upperdir protection.
overlayfs: upperdir is in-use as upperdir/workdir of another mount, mount with '-o index=off' to override exclusive upperdir protection.
overlayfs: upperdir is in-use as upperdir/workdir of another mount, mount with '-o index=off' to override exclusive upperdir protection.
overlayfs: filesystem on './file0' not supported as upperdir
overlayfs: filesystem on './file0' not supported as upperdir
overlayfs: failed to resolve './file0': -2
overlayfs: filesystem on './file0' not supported as upperdir
overlayfs: upperdir is in-use as upperdir/workdir of another mount, mount with '-o index=off' to override exclusive upperdir protection.
overlayfs: upperdir is in-use as upperdir/workdir of another mount, mount with '-o index=off' to override exclusive upperdir protection.
overlayfs: filesystem on './file0' not supported as upperdir
overlayfs: upperdir is in-use as upperdir/workdir of another mount, mount with '-o index=off' to override exclusive upperdir protection.
overlayfs: upperdir is in-use as upperdir/workdir of another mount, mount with '-o index=off' to override exclusive upperdir protection.
overlayfs: upperdir is in-use as upperdir/workdir of another mount, mount with '-o index=off' to override exclusive upperdir protection.
overlayfs: filesystem on './file0' not supported as upperdir
overlayfs: upperdir is in-use as upperdir/workdir of another mount, mount with '-o index=off' to override exclusive upperdir protection.
overlayfs: filesystem on './file0' not supported as upperdir
overlayfs: filesystem on './file0' not supported as upperdir
overlayfs: filesystem on './file0' not supported as upperdir
overlayfs: filesystem on './file0' not supported as upperdir
overlayfs: upperdir is in-use as upperdir/workdir of another mount, mount with '-o index=off' to override exclusive upperdir protection.
overlayfs: upperdir is in-use as upperdir/workdir of another mount, mount with '-o index=off' to override exclusive upperdir protection.
overlayfs: upperdir is in-use as upperdir/workdir of another mount, mount with '-o index=off' to override exclusive upperdir protection.
overlayfs: upperdir is in-use as upperdir/workdir of another mount, mount with '-o index=off' to override exclusive upperdir protection.
overlayfs: upperdir is in-use as upperdir/workdir of another mount, mount with '-o index=off' to override exclusive upperdir protection.
overlayfs: upperdir is in-use as upperdir/workdir of another mount, mount with '-o index=off' to override exclusive upperdir protection.
overlayfs: filesystem on './file0' not supported as upperdir
overlayfs: filesystem on './file0' not supported as upperdir
overlayfs: filesystem on './file0' not supported as upperdir
overlayfs: filesystem on './file0' not supported as upperdir
overlayfs: upperdir is in-use as upperdir/workdir of another mount, mount with '-o index=off' to override exclusive upperdir protection.
overlayfs: upperdir is in-use as upperdir/workdir of another mount, mount with '-o index=off' to override exclusive upperdir protection.
overlayfs: filesystem on './file0' not supported as upperdir
overlayfs: upperdir is in-use as upperdir/workdir of another mount, mount with '-o index=off' to override exclusive upperdir protection.
overlayfs: upperdir is in-use as upperdir/workdir of another mount, mount with '-o index=off' to override exclusive upperdir protection.
overlayfs: upperdir is in-use as upperdir/workdir of another mount, mount with '-o index=off' to override exclusive upperdir protection.
overlayfs: filesystem on './file0' not supported as upperdir
overlayfs: upperdir is in-use as upperdir/workdir of another mount, mount with '-o index=off' to override exclusive upperdir protection.
overlayfs: filesystem on './file0' not supported as upperdir
overlayfs: filesystem on './file0' not supported as upperdir
overlayfs: filesystem on './file0' not supported as upperdir
overlayfs: upperdir is in-use as upperdir/workdir of another mount, mount with '-o index=off' to override exclusive upperdir protection.
overlayfs: filesystem on './file0' not supported as upperdir
overlayfs: upperdir is in-use as upperdir/workdir of another mount, mount with '-o index=off' to override exclusive upperdir protection.
overlayfs: filesystem on './file0' not supported as upperdir
overlayfs: filesystem on './file0' not supported as upperdir
overlayfs: upperdir is in-use as upperdir/workdir of another mount, mount with '-o index=off' to override exclusive upperdir protection.
overlayfs: upperdir is in-use as upperdir/workdir of another mount, mount with '-o index=off' to override exclusive upperdir protection.
overlayfs: upperdir is in-use as upperdir/workdir of another mount, mount with '-o index=off' to override exclusive upperdir protection.
overlayfs: upperdir is in-use as upperdir/workdir of another mount, mount with '-o index=off' to override exclusive upperdir protection.
overlayfs: filesystem on './file0' not supported as upperdir
overlayfs: filesystem on './file0' not supported as upperdir
overlayfs: filesystem on './file0' not supported as upperdir
overlayfs: upperdir is in-use as upperdir/workdir of another mount, mount with '-o index=off' to override exclusive upperdir protection.
overlayfs: upperdir is in-use as upperdir/workdir of another mount, mount with '-o index=off' to override exclusive upperdir protection.
overlayfs: filesystem on './file0' not supported as upperdir
overlayfs: upperdir is in-use as upperdir/workdir of another mount, mount with '-o index=off' to override exclusive upperdir protection.
overlayfs: upperdir is in-use as upperdir/workdir of another mount, mount with '-o index=off' to override exclusive upperdir protection.
overlayfs: upperdir is in-use as upperdir/workdir of another mount, mount with '-o index=off' to override exclusive upperdir protection.
overlayfs: upperdir is in-use as upperdir/workdir of another mount, mount with '-o index=off' to override exclusive upperdir protection.
overlayfs: filesystem on './file0' not supported as upperdir
overlayfs: filesystem on './file0' not supported as upperdir
overlayfs: filesystem on './file0' not supported as upperdir
overlayfs: upperdir is in-use as upperdir/workdir of another mount, mount with '-o index=off' to override exclusive upperdir protection.
overlayfs: upperdir is in-use as upperdir/workdir of another mount, mount with '-o index=off' to override exclusive upperdir protection.
overlayfs: filesystem on './file0' not supported as upperdir
overlayfs: filesystem on './file0' not supported as upperdir
overlayfs: filesystem on './file0' not supported as upperdir
overlayfs: upperdir is in-use as upperdir/workdir of another mount, mount with '-o index=off' to override exclusive upperdir protection.
overlayfs: upperdir is in-use as upperdir/workdir of another mount, mount with '-o index=off' to override exclusive upperdir protection.
overlayfs: upperdir is in-use as upperdir/workdir of another mount, mount with '-o index=off' to override exclusive upperdir protection.
overlayfs: upperdir is in-use as upperdir/workdir of another mount, mount with '-o index=off' to override exclusive upperdir protection.
overlayfs: failed to resolve './file0': -2
overlayfs: filesystem on './file0' not supported as upperdir
overlayfs: upperdir is in-use as upperdir/workdir of another mount, mount with '-o index=off' to override exclusive upperdir protection.
overlayfs: upperdir is in-use as upperdir/workdir of another mount, mount with '-o index=off' to override exclusive upperdir protection.
overlayfs: filesystem on './file0' not supported as upperdir
overlayfs: filesystem on './file0' not supported as upperdir
overlayfs: upperdir is in-use as upperdir/workdir of another mount, mount with '-o index=off' to override exclusive upperdir protection.
overlayfs: upperdir is in-use as upperdir/workdir of another mount, mount with '-o index=off' to override exclusive upperdir protection.
overlayfs: upperdir is in-use as upperdir/workdir of another mount, mount with '-o index=off' to override exclusive upperdir protection.
overlayfs: upperdir is in-use as upperdir/workdir of another mount, mount with '-o index=off' to override exclusive upperdir protection.
overlayfs: filesystem on './file0' not supported as upperdir
overlayfs: filesystem on './file0' not supported as upperdir
overlayfs: filesystem on './file0' not supported as upperdir
overlayfs: upperdir is in-use as upperdir/workdir of another mount, mount with '-o index=off' to override exclusive upperdir protection.
overlayfs: upperdir is in-use as upperdir/workdir of another mount, mount with '-o index=off' to override exclusive upperdir protection.
overlayfs: failed to resolve './file0': -2
overlayfs: upperdir is in-use as upperdir/workdir of another mount, mount with '-o index=off' to override exclusive upperdir protection.
overlayfs: upperdir is in-use as upperdir/workdir of another mount, mount with '-o index=off' to override exclusive upperdir protection.
overlayfs: upperdir is in-use as upperdir/workdir of another mount, mount with '-o index=off' to override exclusive upperdir protection.
overlayfs: upperdir is in-use as upperdir/workdir of another mount, mount with '-o index=off' to override exclusive upperdir protection.
overlayfs: filesystem on './file0' not supported as upperdir
overlayfs: filesystem on './file0' not supported as upperdir
overlayfs: upperdir is in-use as upperdir/workdir of another mount, mount with '-o index=off' to override exclusive upperdir protection.
overlayfs: filesystem on './file0' not supported as upperdir


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