[Samba] strange default share ACLS's, where do they come from?

[Roel van Meer]

Hi everyone,

I have a Samba 4.2.3 PDC server with some shares on it. If I create a new  
share, it immediately has some strange ACL's. Could anyone tell me where  
these come from?

Example:

root at corrumpeer:/# cat <<EOF>>/etc/samba/smb.conf
[test3]
  path = /tmp/test3
EOF

root at corrumpeer:/# mkdir /tmp/test3
root at corrumpeer:/# chown root:users /tmp/test3
root at corrumpeer:/# chmod 0770 /tmp/test3

root at corrumpeer:/# smbcacls //corrumpeer/test3 \\ -Uadmin%password

REVISION:1
CONTROL:SR|DP
OWNER:Unix User\root
GROUP:BUILTIN\Users
ACL:Unix User\root:ALLOWED/0x0/FULL
ACL:BUILTIN\Users:ALLOWED/0x0/FULL
ACL:Everyone:ALLOWED/0x0/
ACL:S-1-5-88-3-16888:DENIED/0x0/
ACL:S-1-5-88-1-0:DENIED/0x0/
ACL:S-1-5-88-2-100:DENIED/0x0/
ACL:Creator Owner:ALLOWED/OI|CI|IO/FULL
ACL:Creator Group:ALLOWED/OI|CI|IO/FULL
ACL:Everyone:ALLOWED/OI|CI|IO/RWDPO

root at corrumpeer:/# getfattr -m '.*' /tmp/test3
<no output>

root at corrumpeer:/# getfattr -m '.*' /tmp
<no output>

root at corrumpeer:/# getfacl /tmp/test3
getfacl: Removing leading '/' from absolute path names
# file: tmp/test3
# owner: root
# group: users
user::rwx
group::rwx
other::---

root at corrumpeer:/# getfacl /tmp
getfacl: Removing leading '/' from absolute path names
# file: tmp
# owner: root
# group: root
# flags: --t
user::rwx
group::rwx
other::rwx

So no ACLS or extended attributes on the dir or the parent (or / for that  
matter) but still smbcacls shows these strange ACL's.

I can use the computer management tool (per the wiki 
https://wiki.samba.org/index.php/Setup_and_configure_file_shares_with_Windows_ACLs ) 
to check the ACLs on the share and they are the same there. But where do  
they come from? Is there a place where you can configure default ACL's for  
new shares?

Thanks a lot,

Roel



/etc/samba/smb.comf:
[global]
        workgroup = CUSTOMER
        netbios name = CORRUMPEER
        server string = corrumpeer

        interfaces = 192.168.1.1/24 127.255.255.255/8
        bind interfaces only = Yes
        hosts allow = 192.168.1.0/255.255.255.0 127.0.0.1
        max protocol = SMB3

        log level = 1
        log file = /var/log/samba/samba.log
        max log size = 5000
        syslog = No

        domain logons = Yes
        logon script = %U.bat

        os level = 254
        preferred master = Yes
        domain master = Yes
        local master = Yes
        wins support = Yes

        time server = Yes
        name resolve order = host wins bcast

        passdb backend = ldapsam:ldap://localhost
        ldap suffix = dc=customer,dc=net
        ldap machine suffix = ou=Computers
        ldap user suffix = ou=Users
        ldap group suffix = ou=Groups
        ldap idmap suffix = ou=Idmap
        ldap admin dn = cn=admin,dc=customer,dc=net
        ldap ssl = No
        idmap config * : backend = tdb
        idmap config * : range = 1000000-1999999
        idmap config CUSTOMER : backend  = rid
        idmap config CUSTOMER : range = 10000-20000
        idmap config CUSTOMER : base_rid    = 0

        printing = cups
        min print space = 1000

        create mask = 0660
        force create mode = 0660
        directory mask = 0770
        force directory mode = 0770

        vfs objects = acl_xattr fruit streams_xattr

        acl allow execute always = Yes
        acl group control = Yes
        map acl inherit = Yes
        store dos attributes = Yes