Exact, les droits des users sur les répertoires se gèrent dans le fichier samba.conf (ce qui oblige à un rédémarrage samba pour les modifier)

voici quelques exemples

# The __SAMBA_PRIVATE_FOLDER__ directory, usable only by __USER_LOGIN__ :
[__USER_LOGIN_____SAMBA_PRIVATE_FOLDER__]
   comment = __USER_LOGIN__'s __SAMBA_PRIVATE_FOLDER__ directory
   path = /__LINUX_HOME_FOLDER__/__USER_LOGIN__/__SAMBA_PRIVATE_FOLDER­__
   valid users = __USER_LOGIN__
   public = no
   writable = yes
   printable = no
   create mask = 0600
   directory mask = 0700
# Note that __USER_LOGIN__ requires write access to the /home/__USER_LOGIN__ directory.

# The __SAMBA_PUBLIC_FOLDER__ accessible directory, but read only for others than __USER_LOGIN__ :
[__USER_LOGIN_____SAMBA_PUBLIC_FOLDER__]
   comment = __USER_LOGIN__'s __SAMBA_PUBLIC_FOLDER__ directory
   path = /__LINUX_HOME_FOLDER__/__USER_LOGIN__/__SAMBA_PUBLIC_FOLDER_­_
   public = yes
   writable = yes
   printable = no
   write list = __USER_LOGIN__
   create mask = 0644
   directory mask = 0755


# A private directory, usable only by __GROUP_NAME__. Note that __GROUP_NAME__ requires write
# access to the /__LINUX_HOME_FOLDER__/__GROUP_NAME__ directory.
[__GROUP_NAME___private]
   comment = __GROUP_NAME__'s private area
   path = /__LINUX_HOME_FOLDER__/__GROUP_NAME__/__SAMBA_PRIVATE_FOLDER­__
   valid users = @__GROUP_NAME__
   public = no
   writable = yes
   printable = no
   create mask = 0765


# A group accessible directory, but read only, except for members of __GROUP_NAME__.
[__GROUP_NAME___public]
   comment = __GROUP_NAME__'s public area
   path = /__LINUX_HOME_FOLDER__/__GROUP_NAME__/__SAMBA_PUBLIC_FOLDER_­_
   public = yes
   writable = yes
   printable = no
   write list = @__GROUP_NAME__
   create mask = 0765