samba 设置如下，其中cdrom和usb两个文件夹在xp中始终只有浏览权限，请问要怎么设置才有读写权限！
======================= Global Settings =====================================
[global]
# workgroup = NT-Domain-Name or Workgroup-Name, eg: MIDEARTH
; workgroup = WORKGROUP
# server string is the equivalent of the NT Description field
server string = Samba Server
# Security mode. Defines in which mode Samba will operate. Possible
# values are share, user, server, domain and ads. Most people will want
# user level security. See the Samba-HOWTO-Collection for details.
security = User
# This option is important for security. It allows you to restrict
# connections to machines which are on your local network. The
# following example restricts access to two C class networks and
# the "loopback" interface. For more examples of the syntax see
# the smb.conf man page
; hosts allow = 192.168.1. 192.168.2.128.
# If you want to automatically load your printer list rather
# than setting them up individually then you'll need this
; load printers = yes
# you may wish to override the location of the printcap file
; printcap name = /etc/printcap
# on SystemV system setting printcap name to lpstat should allow
# you to automatically obtain a printer list from the SystemV spool
# system
; printcap name = lpstat
# It should not be necessary to specify the print system type unless
# it is non-standard. Currently supported print systems include:
# bsd, cups, sysv, plp, lprng, aix, hpux, qnx
; printing = cups
# This option tells cups that the data has already been rasterized
cups options = raw
# Uncomment this if you want a guest account, you must add this to /etc/passwd
# otherwise the user "nobody" is used
; guest account = pcguest
# this tells Samba to use a separate log file for each machine
# that connects
log file = /var/log/samba/%m.log
# Put a capping on the size of the log files (in Kb).
max log size = 50
# Use password server option only with security = server
# The argument list may include:
# password server = My_PDC_Name [My_BDC_Name] [My_Next_BDC_Name]
# or to auto-locate the domain controller/s
# password server = *
; password server =
# Use the realm option only with security = ads
# Specifies the Active Directory realm the host is part of
; realm = MY_REALM