overlayfs: conflicting lowerdir path
overlayfs: workdir and upperdir must reside under the same mount
BUG: unable to handle kernel paging request at ffffffff0000000e
PGD 8c70067 P4D 8c70067 PUD 0 
Oops: 0002 [#1] PREEMPT SMP KASAN
CPU: 1 PID: 30942 Comm: syz-executor.0 Not tainted 4.19.120-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
RIP: 0010:memset16 arch/x86/include/asm/string_64.h:43 [inline]
RIP: 0010:scr_memsetw include/linux/vt_buffer.h:36 [inline]
RIP: 0010:delete_char drivers/tty/vt/vt.c:854 [inline]
RIP: 0010:csi_P drivers/tty/vt/vt.c:2011 [inline]
RIP: 0010:do_con_trol+0x3b1/0x5c00 drivers/tty/vt/vt.c:2385
Code: 56 3d 00 00 8b 8d 8c 03 00 00 8b 95 34 03 00 00 0f b7 85 c8 03 00 00 48 29 ca 48 2b 54 24 20 89 d9 d1 e9 48 01 d2 49 8d 3c 17 <f3> 66 ab 48 8d bd 78 04 00 00 b8 ff ff 37 00 48 89 fa 48 c1 e0 2a
RSP: 0018:ffff888068d77808 EFLAGS: 00010287
RAX: 0000000000000720 RBX: 0000000000000002 RCX: 0000000000000001
RDX: fffffffe00000000 RSI: 0000000100000010 RDI: ffffffff0000000e
RBP: ffff88804e162540 R08: ffff888044ad6700 R09: 0000000000000005
R10: ffffed1015ce4732 R11: ffff8880ae723993 R12: 1ffff1100d1aef07
R13: ffff88804e1628cc R14: ffff88804e162874 R15: 000000010000000e
FS:  00007f48bc8c6700(0000) GS:ffff8880ae700000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: ffffffff0000000e CR3: 000000004a2b1000 CR4: 00000000001426e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 do_con_write.part.0+0xf55/0x1db0 drivers/tty/vt/vt.c:2798
 do_con_write drivers/tty/vt/vt.c:2566 [inline]
 con_write+0x41/0xe0 drivers/tty/vt/vt.c:3133
 process_output_block drivers/tty/n_tty.c:593 [inline]
 n_tty_write+0x3ee/0x1080 drivers/tty/n_tty.c:2331
 do_tty_write drivers/tty/tty_io.c:960 [inline]
 tty_write+0x452/0x790 drivers/tty/tty_io.c:1044
 __vfs_write+0xf7/0x760 fs/read_write.c:485
 vfs_write+0x206/0x550 fs/read_write.c:549
 ksys_write+0x12b/0x2a0 fs/read_write.c:599
 do_syscall_64+0xf9/0x620 arch/x86/entry/common.c:293
 entry_SYSCALL_64_after_hwframe+0x49/0xbe
RIP: 0033:0x45c829
Code: 0d b7 fb ff c3 66 2e 0f 1f 84 00 00 00 00 00 66 90 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 b6 fb ff c3 66 2e 0f 1f 84 00 00 00 00
RSP: 002b:00007f48bc8c5c78 EFLAGS: 00000246 ORIG_RAX: 0000000000000001
RAX: ffffffffffffffda RBX: 000000000050c3c0 RCX: 000000000045c829
RDX: 0000000000000320 RSI: 00000000200001c0 RDI: 0000000000000003
RBP: 000000000078bf00 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 00000000ffffffff
R13: 0000000000000ce2 R14: 00000000004cf0e0 R15: 00007f48bc8c66d4
Modules linked in:
CR2: ffffffff0000000e
---[ end trace b2ad21de8662583b ]---
RIP: 0010:memset16 arch/x86/include/asm/string_64.h:43 [inline]
RIP: 0010:scr_memsetw include/linux/vt_buffer.h:36 [inline]
RIP: 0010:delete_char drivers/tty/vt/vt.c:854 [inline]
RIP: 0010:csi_P drivers/tty/vt/vt.c:2011 [inline]
RIP: 0010:do_con_trol+0x3b1/0x5c00 drivers/tty/vt/vt.c:2385
Code: 56 3d 00 00 8b 8d 8c 03 00 00 8b 95 34 03 00 00 0f b7 85 c8 03 00 00 48 29 ca 48 2b 54 24 20 89 d9 d1 e9 48 01 d2 49 8d 3c 17 <f3> 66 ab 48 8d bd 78 04 00 00 b8 ff ff 37 00 48 89 fa 48 c1 e0 2a
RSP: 0018:ffff888068d77808 EFLAGS: 00010287
RAX: 0000000000000720 RBX: 0000000000000002 RCX: 0000000000000001
RDX: fffffffe00000000 RSI: 0000000100000010 RDI: ffffffff0000000e
RBP: ffff88804e162540 R08: ffff888044ad6700 R09: 0000000000000005
R10: ffffed1015ce4732 R11: ffff8880ae723993 R12: 1ffff1100d1aef07
R13: ffff88804e1628cc R14: ffff88804e162874 R15: 000000010000000e
FS:  00007f48bc8c6700(0000) GS:ffff8880ae700000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: ffffffff0000000e CR3: 000000004a2b1000 CR4: 00000000001426e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400