Bug 75154 – udev cdrom permissions redundant?

• Product: Gentoo Linux
• Status: RESOLVED INVALID

[Description Mark 2004-12-21 02:05:08 UTC]

udev sets the permissions of /dev/cdrom and /dev/cdroms/cdrom0 to root:cdrom as usual but as they are symlinks to /dev/hdc on my ide machine... 

burrito% eject /dev/cdrom
eject: unable to open `/dev/hdc'

where /dev/hdc 's permissions are 
brw-rw----  1 root root

giving errors such as that above

[Comment 1 Stefan Schweizer (RETIRED) 2004-12-21 02:16:19 UTC]

There have been virious discucssions over this. See the linux-hotplug-devel list for details. It should work wiuth the latest udev, what version do you use? Can you please try the ~x86 version?

[Comment 2 Mark 2004-12-21 02:51:16 UTC]

tried the latest udev version, 50, was using 45 ... same problem, only now /dev/cdrom and /dev/cdroms/cdrom0 have permissions root:root as well as /dev/hdc, though this makes little difference either way, being only symlinks ...

[Comment 3 Stefan Schweizer (RETIRED) 2005-01-28 13:29:42 UTC]

Can you please try to run udevstart?

on my system its like this:

 # ls /dev/hdc -l
brw-rw----  1 root root 22, 0 Jan 28 12:44 /dev/hdc
 # udevstart
 # ls /dev/hdc -l
brw-rw----  1 root disk 22, 0 Jan 28 12:44 /dev/hdc

[Comment 4 Mark 2005-01-28 13:53:05 UTC]

Ran udevstart and did an ls -la /dev/hdc and the permissions are fixed!! 
brw-rw----  1 root cdrom 22, 0 Nov 18 08:35 /dev/hdc

excellent, thanks :D 

But what exactly was happening?

[Comment 5 Stefan Schweizer (RETIRED) 2005-01-28 13:55:41 UTC]

I dont know why the permissions are root:root at the beginning and you need to run udevstart ..
maybe someone else has overridden the permissions, maybe the cdrom detection did not work when the system was started?
however, it sucks to have to run udevstart after every boot/reboot to get :cdrom as group

[Comment 6 Mark 2005-01-28 14:17:19 UTC]

Oh, so I have to run udevstart after every boot? dang. I thought it was fixed for a second there.  

Is this behaviour common for udev?  I mean, I could write a script to run udevstart for me, but that would just be a bandaid fix. 

Is there nothing I can set in /etc/udev to change this?

Thanks

[Comment 7 Greg Kroah-Hartman (RETIRED) 2005-01-29 09:09:10 UTC]

No, that means something like pam or something else is modifying your permissions of the device, and it's not a udev problem.  Take a look and see if pam is doing this.