overlayfs: missing 'lowerdir'
BUG: kernel NULL pointer dereference, address: 0000000000000000
#PF: supervisor read access in kernel mode
#PF: error_code(0x0000) - not-present page
PGD 97ebe067 P4D 97ebe067 PUD 961bf067 PMD 0 
Oops: 0000 [#1] PREEMPT SMP KASAN
CPU: 1 PID: 26937 Comm: syz-executor.1 Not tainted 5.7.0-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
RIP: 0010:__read_once_size include/linux/compiler.h:252 [inline]
RIP: 0010:__sanitizer_cov_trace_pc+0x3f/0x60 kernel/kcov.c:202
Code: c2 00 01 ff 00 74 11 f7 c2 00 01 00 00 74 35 83 b9 04 14 00 00 00 74 2c 8b 91 e0 13 00 00 83 fa 02 75 21 48 8b 91 e8 13 00 00 <48> 8b 32 48 8d 7e 01 8b 89 e4 13 00 00 48 39 cf 73 08 48 89 44 f2
RSP: 0018:ffffc9001658f6d0 EFLAGS: 00010246
RAX: ffffffff8362f473 RBX: 0000000000000002 RCX: ffff8880a67aa580
RDX: 0000000000000000 RSI: ffffffff8943a5d0 RDI: 0000000000000002
RBP: dffffc0000000000 R08: 0000000000000001 R09: ffffffff8362f403
R10: 0000000000000007 R11: ffff8880a67aa580 R12: ffff88809d8e7c90
R13: 0000000000000266 R14: ffff88809f5adf98 R15: ffff88809f5adf80
FS:  00007fed87f1a700(0000) GS:ffff8880ae900000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000000000000000 CR3: 000000009ce03000 CR4: 00000000001406e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 tomoyo_domain_quota_is_ok+0x1b3/0x590 security/tomoyo/util.c:1050
 tomoyo_supervisor+0x270/0x1310 security/tomoyo/common.c:2089
 tomoyo_audit_path_log security/tomoyo/file.c:168 [inline]
 tomoyo_path_permission security/tomoyo/file.c:587 [inline]
 tomoyo_check_open_permission+0x3f7/0x900 security/tomoyo/file.c:777
 security_file_open+0x50/0xc0 security/security.c:1553
 do_dentry_open+0x38f/0x1020 fs/open.c:815
 vfs_open fs/open.c:942 [inline]
 dentry_open+0xc6/0x120 fs/open.c:958
 ovl_dir_read+0x26/0x500 fs/overlayfs/readdir.c:300
 ovl_check_d_type_supported+0x3f/0xb0 fs/overlayfs/readdir.c:1026
 ovl_make_workdir fs/overlayfs/super.c:1156 [inline]
 ovl_get_workdir fs/overlayfs/super.c:1264 [inline]
 ovl_fill_super+0x3101/0x52b0 fs/overlayfs/super.c:1759
 mount_nodev+0x52/0xe0 fs/super.c:1463
 legacy_get_tree+0xea/0x180 fs/fs_context.c:592
 vfs_get_tree+0x88/0x270 fs/super.c:1547
 do_new_mount fs/namespace.c:2874 [inline]
 do_mount+0x17e8/0x2900 fs/namespace.c:3199
 __do_sys_mount fs/namespace.c:3409 [inline]
 __se_sys_mount+0xd3/0x100 fs/namespace.c:3386
 do_syscall_64+0xf3/0x1b0 arch/x86/entry/common.c:295
 entry_SYSCALL_64_after_hwframe+0x49/0xb3
RIP: 0033:0x45ca59
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:00007fed87f19c78 EFLAGS: 00000246 ORIG_RAX: 00000000000000a5
RAX: ffffffffffffffda RBX: 00000000004f6ea0 RCX: 000000000045ca59
RDX: 0000000020000080 RSI: 0000000020000040 RDI: 0000000000000000
RBP: 000000000078bf00 R08: 0000000020000280 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 00000000ffffffff
R13: 0000000000000773 R14: 00000000004ca5ad R15: 00007fed87f1a6d4
Modules linked in:
CR2: 0000000000000000
---[ end trace 8168988a4c16e5e9 ]---
RIP: 0010:__read_once_size include/linux/compiler.h:252 [inline]
RIP: 0010:__sanitizer_cov_trace_pc+0x3f/0x60 kernel/kcov.c:202
Code: c2 00 01 ff 00 74 11 f7 c2 00 01 00 00 74 35 83 b9 04 14 00 00 00 74 2c 8b 91 e0 13 00 00 83 fa 02 75 21 48 8b 91 e8 13 00 00 <48> 8b 32 48 8d 7e 01 8b 89 e4 13 00 00 48 39 cf 73 08 48 89 44 f2
RSP: 0018:ffffc9001658f6d0 EFLAGS: 00010246
RAX: ffffffff8362f473 RBX: 0000000000000002 RCX: ffff8880a67aa580
RDX: 0000000000000000 RSI: ffffffff8943a5d0 RDI: 0000000000000002
RBP: dffffc0000000000 R08: 0000000000000001 R09: ffffffff8362f403
R10: 0000000000000007 R11: ffff8880a67aa580 R12: ffff88809d8e7c90
R13: 0000000000000266 R14: ffff88809f5adf98 R15: ffff88809f5adf80
FS:  00007fed87f1a700(0000) GS:ffff8880ae800000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000055d4ab9de160 CR3: 000000009ce03000 CR4: 00000000001406f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400