4

I installed ubuntu 11.10. During installation, I created the default user (named MS). I can browse/edit and do anything in my hard disk(I have 7 partitions).

Today I created a new user named (ABC), this user cannot access my internal hard disk partitions. When I click on each partition the hard disk icon suddenly disappear from the left side device panel(inside home folder there is things like devices, bookmarks etc). So I checked /media directory and it says "folder contents cannot be displayed".

cat /etc/fstab

# /etc/fstab: static file system information.
#
# Use 'blkid' to print the universally unique identifier for a
# device; this may be used with UUID= as a more robust way to name devices
# that works even if disks are added and removed. See fstab(5).
#
# <file system> <mount point>   <type>  <options>       <dump>  <pass>
proc                                       /proc        proc  nodev,noexec,nosuid  0  0  
# / was on /dev/sda1 during installation
UUID=9fa65e41-5c75-4636-a3b5-961739b245c2  /            ext4  errors=remount-ro    0  1

fdisk -l

Disk /dev/sda: 500.1 GB, 500107862016 bytes
255 heads, 63 sectors/track, 60801 cylinders, total 976773168 sectors
Units = sectors of 1 * 512 = 512 bytes
Sector size (logical/physical): 512 bytes / 512 bytes
I/O size (minimum/optimal): 512 bytes / 512 bytes
Disk identifier: 0x000b2307

   Device Boot      Start         End      Blocks   Id  System

/dev/sda1            2048    39997439    19997696   83  Linux

/dev/sda2   *    39999488    81946623    20973568   83  Linux

/dev/sda3        81947565   123877214    20964825   83  Linux

/dev/sda4       123887614   976773119   426442753    5  Extended

/dev/sda5       123887616   333602815   104857600   83  Linux

/dev/sda6       333604864   543320063   104857600   83  Linux

/dev/sda7       543322112   753037311   104857600   83  Linux

/dev/sda8       753039360   976773119   111866880   83  Linux

Information about the users

id ms
uid=1000(ms) gid=1000(ms) groups=1000(ms),4(adm),20(dialout),24(cdrom),46(plugdev),116(lpadmin),118(admin),124(sambashare)

id abc
uid=1002(abc) gid=1002(abc) groups=1002(abc),4(adm),20(dialout),24(cdrom),46(plugdev),116(lpadmin),118(admin),124(sambashare)

Also I got the following things while mounting the partition under the user abc.

Dec 21 23:04:15 ms-Lenovo-G550 kernel: [   64.093923] EXT4-fs (sda8): warning: maximal mount count reached, running e2fsck is recommended
Dec 21 23:04:15 ms-Lenovo-G550 kernel: [   64.095606] EXT4-fs (sda8): recovery complete
Dec 21 23:04:15 ms-Lenovo-G550 kernel: [   64.095611] EXT4-fs (sda8): mounted filesystem with ordered data mode. Opts: (null)
Dec 21 23:04:16 ms-Lenovo-G550 kernel: [   65.619595] EXT4-fs (sda7): recovery complete
Dec 21 23:04:16 ms-Lenovo-G550 kernel: [   65.619602] EXT4-fs (sda7): mounted filesystem with ordered data mode. Opts: (null)
Dec 21 23:04:17 ms-Lenovo-G550 kernel: [   66.250818] EXT4-fs (sda6): warning: maximal mount count reached, running e2fsck is recommended
Dec 21 23:04:17 ms-Lenovo-G550 kernel: [   66.251195] EXT4-fs (sda6): recovery complete
Dec 21 23:04:17 ms-Lenovo-G550 kernel: [   66.251362] EXT4-fs (sda6): mounted filesystem with ordered data mode. Opts: (null)
Dec 21 23:04:18 ms-Lenovo-G550 kernel: [   67.080910] EXT4-fs (sda5): recovery complete
Dec 21 23:04:18 ms-Lenovo-G550 kernel: [   67.080916] EXT4-fs (sda5): mounted filesystem with ordered data mode. Opts: (null)

Here are the result of /media after mounting partitions.

abc@ms-Lenovo-G550:~$ ls -al /media/

total 28
drwxr-xr-x  7 root root 4096 2011-12-29 07:34 .
drwxr-xr-x 24 root root 4096 2011-12-11 22:30 ..
drwxrw----  6 ms   ms   4096 2011-11-19 15:45 Films
drwx------ 17 ms   ms   4096 2011-12-22 21:59 Misc
dr-x------  9 ms   ms   4096 2011-12-20 23:18 Ms
drwx------  6 ms   ms   4096 2011-12-28 18:50 Softs
drwx------  6 ms   ms   4096 2011-11-17 03:06 Song

Also different partitions are used to arrange things in an easy manner.

Thanks, Vipin MS

lumbric
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Vipin Ms
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2 Answers2

4

Your problem is with the user/group permissions on ext4. For abc to access read only, you need to set the permissions to 755 (on eg. /home/Ms) with

sudo chmod -R 755 /media/Ms

This will grant read only access for all the users on the system. If you want more security create a new group, add the two users to that group, and chown + chmod

sudo groupadd new_group
sudo usermod -a -G new_group ms
sudo usermod -a -G new_group abc
sudo chown ms:new_group -R /media/Ms
sudo chmod 770 -R /media/Ms

This will set the permissions to rwxrwx---, and only the two users can access the Ms folder.

Marco Ceppi
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gajdipajti
  • 3,501
1

work around

If you want, you could set your partitions to be automatically mounted on boot for all users. It depends on you, if this is what you want or not. You can mount them to any point in your file system or even at several different points (by use of the bind option). This could be a possible work a round for your problem, so if you want you can try this out.

How to do so, is answered in this question: How to mount an internal HDD on start-up?

Community
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lumbric
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