Comment 48 for bug 10550

Hi,

I have the same problem with broken udf permissions generated by a comercial DVD player/recorder, a Samsung DVD-SH873.

Ubuntu intrepid
Linux ubuntu 2.6.27-11-generic

# ls -l /media
...
d--x--x--- 3 4294967295 4294967295 84 2009-01-31 17:36 cdrom0
...

In my case, there is missing world acces permission and there is missing read permissions at all. Very surprisingly, it only happens in the top (root) directory in the file systems because the contents seems to have right permissions:

# ls -l /media/cdrom0
dr-xr-xr-x 2 4294967295 4294967295 2232 2009-01-31 17:36 MOVIE
...

This is a data DVD with recorded divx files, so it is not a DVD-VIDEO disk, so the problem is not only about DVD-VIDEO.

This particular DVD cannot be mounted as iso9660, so this workaround does not help:

# mount -t iso9660 /dev/scd0 /media/cdrom0/
mount: block device /dev/scd0 is write-protected, mounting read-only
mount: wrong fs type, bad option, bad superblock on /dev/scd0,
       missing codepage or helper program, or other error
       In some cases useful info is found in syslog - try
       dmesg | tail or so

So, none of the proposed solutions would work for me (except being root).

In my opinion, the good solution would be something like this:

1. At kernel driver level, there should be an option to set "effective" file permissions different from what is in the filesystem. When you mount the device, you see the permissions on the filesystem and they are preserved when you copy, etc. as people doing backups like, but you will be able to read and list files based on "effective" permissions that override fs permissions. Simple said, the kernel do not honor fs permissions at read time.

2. At desktop level, you (the user) are able to select related properties to removable media in a place like System->Preferences->Removable media. The system would use the above related facilities to implement that. The options may be:
- Make removable media always readable
  - Apply only to read-only media
- Make files copied from removable media readable

I hope people at Ubuntu/Linux Kernel would implement something like that. Unfortunately, my coding skills are far from being able to do something like that.