i can mount dvd as user but cannot read it

makz · 2004-12-15 05:21:41

I'm trying to read a data dvd as user but i can do it only as root.

my fstab is like that:
/dev/cdroms/cdrom1 /mnt/dvd udf ro,user,noauto,unhide 0 0

i can mount it as user with the command mount /mnt/dvd and when i do cd /mnt/dvd i got Permission Denied.

my /etc/group:
optical:!:105:makz (my username is makz)

/mnt/dvd directory permissions (not mounted):
drwxr-xr-x 2 root users 4096 2004-12-14 23:33 /mnt/dvd

/mnt/dvd directory permissions (when mounted)
dr--r--r-- 2 4294967295 4294967295 3852 2004-12-14 20:45 /mnt/dvd

/dev/cdroms/cdrom1 permissions:
brw-rw---- 1 root optical 22, 0 1969-12-31 18:00 /dev/cdroms/cdrom1

the same as /dev/ide/host0/bus1/target0/lun0/cd (/dev/cdroms/cdrom1 is a symlink to this)
brw-rw---- 1 root optical 22, 0 1969-12-31 18:00 /dev/ide/host0/bus1/target0/lun0/cd

/etc/devfsd.conf:
REGISTER ^cdroms/.* PERMISSIONS root.optical 660

this is very strange, i don't know what's heppening because all seems ok.

makz · 2004-12-15 05:50:36

I changed my fstab so /mnt/dvd is mounted as a iso9660 filesystem instead of udf and now i can read it as user but the filenames are like this:
_g06d4~1.avi

instead of

[GF] Gantz 01 DVD-RIP [sin censura] spanish sub DIVX 5.2.avi

do you think this is a bug?

Stanislav · 2004-12-15 06:24:53

you can try changing the filesystem to "auto" . maybe this will help.

makz · 2004-12-15 06:46:48

it didn't work, also i tried with this:
/dev/cdroms/cdrom1 /mnt/dvd auto user,uid=root,gid=optical,umask=0,noauto,unhide 0 0
without luck.

sarah31 · 2004-12-15 16:43:01

did you add your user to the optical group?

that is why you cannot mount as user as far as i know.

makz · 2004-12-15 20:32:48

my /etc/group:
optical:!:105:makz (my username is makz)

i _can_ mount it as user, what i _can't_ is read it as user.

phrakture · 2004-12-15 20:41:30

makz wrote:

I changed my fstab so /mnt/dvd is mounted as a iso9660 filesystem instead of udf and now i can read it as user but the filenames are like this:
_g06d4~1.avi
instead of
[GF] Gantz 01 DVD-RIP [sin censura] spanish sub DIVX 5.2.avi
do you think this is a bug?

did you burn this in windows? it looks like a DOS 8.3 filename (DOS has a limit of 8 chars - dot - 3 chars)

makz · 2004-12-16 01:26:48

yes, a friend of mine burned that in windows.

makz · 2004-12-24 05:06:55

i had to manually change the permissions in the source code of the udf module, in the file inode.c, in the convert_permissions function, i changed the value of mode to 511 (777 octal) and now it works but i don't know why.

oscar · 2004-12-24 08:58:44

makz wrote:

it didn't work, also i tried with this:
/dev/cdroms/cdrom1 /mnt/dvd auto user,uid=root,gid=optical,umask=0,noauto,unhide 0 0
without luck.

uid and gid specifies that user/group that should have the permissions to access etc the resource when mounted.
If you tell your fstab that only root should own it (yes, that's what your fstab says), it wont work for your user!

adstro · 2005-03-06 14:08:03

Is there another solution to this problem other than changing the code in inode.c. I am experiencing the same issue. Users can mount the UDF filesystem but the mounted dir has does not have the execute permissions for users.

Here is what my fstab file says:
dev/cdroms/cdrom0 /mnt/dvdrom udf ro,user,noauto,unhide,umask=0222,gid=users

I have tried many variations with no success. Any input would be appreciated.

kakabaratruskia · 2005-03-06 14:50:55

To open data dvd's I use the iso9660 filesystem, not udf.

try this:

mount -t iso9660 dev/cdroms/cdrom0 /mnt/dvdrom

jerem · 2005-03-07 07:53:04

I also mount my windows-nero-burnt dvds with iso9660 fs and I have no problem with long-names files.

However, I have UTF8 and some other characters encoding sets included in my kernel, which may help.

makz · 2005-08-25 01:06:12

Here is the section of inode.c, if someone needs it someday.

udf_convert_permissions(struct fileEntry *fe)
{
        mode_t mode;
        uint32_t permissions;
        uint32_t flags;

        permissions = le32_to_cpu(fe->permissions);
        flags = le16_to_cpu(fe->icbTag.flags);

        udf_info("perm: %d %on", permissions, permissions);

        mode =  (( permissions      ) & S_IRWXO) |
                (( permissions >> 2 ) & S_IRWXG) |
                (( permissions >> 4 ) & S_IRWXU) |
                (( flags & ICBTAG_FLAG_SETUID) ? S_ISUID : 0) |
                (( flags & ICBTAG_FLAG_SETGID) ? S_ISGID : 0) |
                (( flags & ICBTAG_FLAG_STICKY) ? S_ISVTX : 0);

mode = 365;

        return mode;
}

The line changed is the one that says mode = 365, 365 is 555 in octal, you can change this number according to your needs.

i used this converter to convert the permissions to decimal, permissions are an octal number, in this case, 555 (the permissions i wanted) to decimal is 365.

I informed the udf linux project people about this problem some months ago but they didn't give a satisfying answer, i hope this get fixed soon, if the project is not dead.

Arch Linux

#1 2004-12-15 05:21:41

i can mount dvd as user but cannot read it

#2 2004-12-15 05:50:36

Re: i can mount dvd as user but cannot read it

#3 2004-12-15 06:24:53

Re: i can mount dvd as user but cannot read it

#4 2004-12-15 06:46:48

Re: i can mount dvd as user but cannot read it

#5 2004-12-15 16:43:01

Re: i can mount dvd as user but cannot read it

#6 2004-12-15 20:32:48

Re: i can mount dvd as user but cannot read it

#7 2004-12-15 20:41:30

Re: i can mount dvd as user but cannot read it

#8 2004-12-16 01:26:48

Re: i can mount dvd as user but cannot read it

#9 2004-12-24 05:06:55

Re: i can mount dvd as user but cannot read it

#10 2004-12-24 08:58:44

Re: i can mount dvd as user but cannot read it

#11 2005-03-06 14:08:03

Re: i can mount dvd as user but cannot read it

#12 2005-03-06 14:50:55

Re: i can mount dvd as user but cannot read it

#13 2005-03-07 07:53:04

Re: i can mount dvd as user but cannot read it

#14 2005-08-25 01:06:12

Re: i can mount dvd as user but cannot read it

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