When I write ls -la the output is :tusharmakkar08-Satellite-C660 tusharmakkar08 # ls -latotal 88drwxr-x---+ 10 root root  4096 Apr 18 19:43 .drwxr-xr-x   4 root root  4096 Mar 18 17:35 ..drwxr-xr-x   4 root root 32768 Jan  1  1970 CFB1-5DDAdrwxrwxrwx   2 root root  4096 Feb 23 00:09 FA38015738011473drwxrwxrwx   2 root root  4096 Apr 17 14:00 Localdrwxrwxrwx   2 root root  4096 Mar 19 05:04 Local\040Disk1drwxrwxrwx   2 root root  4096 Apr 18 19:43 Local\134x20Disk1drwxrwxrwx   2 root root  4096 Feb 23 00:09 Local Diskdrwxrwxrwx   1 root root 24576 Apr 19 15:15 Local\x20Disk1drwxrwxrwx   2 root root  4096 Feb 23 00:08 PENDRIVENow I want to change the permissions of CFB1-5DDA .. but i am unable to do so .When I writechmod 777 CFB1-5DDAstill the permissions remain unchanged.The output of sudo blkid -c /dev/nullis tusharmakkar08-Satellite-C660 tusharmakkar08 # sudo blkid -c /dev/null/dev/sda2: UUID=FA38015738011473 TYPE=ntfs /dev/sda3: LABEL=Local Disk UUID=01CD72098BB21B70 TYPE=ntfs /dev/sda4: UUID=2ca94bc3-eb3e-41cf-ad06-293cf89791f2 TYPE=ext4 /dev/sda5: UUID=CFB1-5DDA TYPE=vfatThe output of cat /etc/fstab istusharmakkar08-Satellite-C660 tusharmakkar08 # cat /etc/fstab# /etc/fstab: static file system information.##                #Entry for /dev/sda4 :UUID=2ca94bc3-eb3e-41cf-ad06-293cf89791f2   /   ext4    defaults    01#Entry for /dev/sda2 :UUID=FA38015738011473   /media/sda2 ntfs-3g defaults,locale=en_IN   0   0#Entry for /dev/sda5 :UUID=CFB1-5DDA  /media/tusharmakkar08/CFB1-5DDA vfat    defaults    0   0/dev/sda3   /media/tusharmakkar08/Local\134x20Disk1 fuseblk defaults,nosuid,nodev,allow_other,blksize=4096  0   0/dev/sda3   /media/tusharmakkar08/Local\x20Disk1    ntfs-3g defaults,nosuid,nodev,locale=en_IN  0   0#/dev/sda3  /media/tusharmakkar08/Local\134x20Disk1 ntfs    defaults,nls=utf8,umask=0222,nosuid,nodev   0   0And the output of mountistusharmakkar08-Satellite-C660 tusharmakkar08 # mount/dev/sda4 on / type ext4 (rw)proc on /proc type proc (rw,noexec,nosuid,nodev)sysfs on /sys type sysfs (rw,noexec,nosuid,nodev)none on /sys/fs/fuse/connections type fusectl (rw)none on /sys/kernel/debug type debugfs (rw)none on /sys/kernel/security type securityfs (rw)udev on /dev type devtmpfs (rw,mode=0755)devpts on /dev/pts type devpts (rw,noexec,nosuid,gid=5,mode=0620)tmpfs on /run type tmpfs (rw,noexec,nosuid,size=10%,mode=0755)none on /run/lock type tmpfs (rw,noexec,nosuid,nodev,size=5242880)none on /run/shm type tmpfs (rw,nosuid,nodev)none on /run/user type tmpfs (rw,noexec,nosuid,nodev,size=104857600,mode=0755)cgroup on /sys/fs/cgroup type tmpfs (rw,relatime,mode=755)cgroup on /sys/fs/cgroup/cpuset type cgroup (rw,relatime,cpuset)cgroup on /sys/fs/cgroup/cpu type cgroup (rw,relatime,cpu)cgroup on /sys/fs/cgroup/cpuacct type cgroup (rw,relatime,cpuacct)cgroup on /sys/fs/cgroup/memory type cgroup (rw,relatime,memory)cgroup on /sys/fs/cgroup/devices type cgroup (rw,relatime,devices)cgroup on /sys/fs/cgroup/freezer type cgroup (rw,relatime,freezer)cgroup on /sys/fs/cgroup/blkio type cgroup (rw,relatime,blkio)cgroup on /sys/fs/cgroup/perf_event type cgroup (rw,relatime,perf_event)/dev/sda2 on /media/sda2 type fuseblk (rw,nosuid,nodev,allow_other,blksize=4096)/dev/sda5 on /media/tusharmakkar08/CFB1-5DDA type vfat (rw)/dev/sda3 on /media/tusharmakkar08/Local\x20Disk1 type fuseblk (rw,nosuid,nodev,allow_other,blksize=4096)binfmt_misc on /proc/sys/fs/binfmt_misc type binfmt_misc (rw,noexec,nosuid,nodev)gvfsd-fuse on /run/user/tusharmakkar08/gvfs type fuse.gvfsd-fuse (rw,nosuid,nodev,user=tusharmakkar08)
Unable to change permissions of file system root
permissions;mount;chmod;vfat
chmod 777 CFB1-5DDA fails because CFB1-5DDA is a mount point and the mounted file system is vfat. So you are trying to write meta data to a file system which the file system does not support (i.e. cannot store). Simple as that.strace chmod 777 CFB1-5DDA shows you the kernel error.In order to change the access rights you have to change the mount (-o remount or umount; mount).