I have a public SMB share mainly as a media dump. Everyone can read and write, without any auth - as intended. However, if I copy files via SSH (as a regular user, not the samba user), these files are of course owned by that user and thus not writable for the samba user - so I can't touch these files via SMB.

My config looks like this

[public]
  path = /path/to/samba/public
  guest ok = yes
  writeable = yes
  browseable = yes
  create mask = 0664
  directory mask = 0775
  force user = sambapub
  force group = users

I can fix the permissions by simply chown/chmod all files, but that's not really a solution.