permissions problems

Mistshadow · 02-05-2004, 09:51 PM

Permissions on my system for the devices keep reverting to root-only. This is particularly bad since I have a second hard drive, formatted as /home, and permissions on it keep reverting too. I tried to chmod them, as I was told that even hardware is a file on *ix systems, but that didn't work - it just says that's "not supported on protocol devices".

It keeps happening every time I su root or use a device while logged in as root. Now, occasionally I've had to su root or log in as root. And then I'm stuck with my 2nd hd, cd-rw, dvd-rom and floppy being root-only.

What do I do to fix this? Is there a permanent fix for it (permanent until I change the permissions deliberately myself)?

Thanks in advance.

(Edit: I did search first, both here and on google, but everything that turns up just instructs me how to chmod files, which I've already tried.)

Tinkster · 02-05-2004, 10:17 PM

Which distro is this happening with?
Certainly not Slack ;)

Are you using devfs?

Cheers,
Tink

Mistshadow · 02-06-2004, 12:24 AM

Quote:

Originally posted by Tinkster
Which distro is this happening with?
Certainly not Slack

Are you using devfs?

Cheers,
Tink

SuSE 8.2 and the latest Mepis. But I've seen this happen before with other distros I tried out (but, no, not Slack

).

As to devfs, what's that? It might be under a different name on my distro, maybe not. It's not on the menu, so how would I start it from a shell? Just tap in devfs?

Thanks for trying to help.

Tinkster · 02-06-2004, 12:31 PM

devfs is an approach used to "simplify" the
use (the reading/handling) of /dev
It will only create nodes for devices actually
used.... I've only got it installed on one of
my machines (just for testing, really) ...

Compare the output of these two ls commands:

Quote:

Code:

[tink@diggn:~]$ ls -l /dev | wc -l
   2499
[tink@diggn:~]$ ls -l /dev
-rwxr-xr-x    1 root     root        38812 2002-06-12 06:41 MAKEDEV
-rw-r--r--    1 root     root         1162 2002-06-12 06:41 README.MAKEDEV
lrwxrwxrwx    1 root     root            4 2002-12-28 23:33 X0R -> null
crw-rw----    1 root     root      10, 175 2001-03-26 09:04 agpgart
crw-rw----    1 root     root       1,  10 2001-03-26 09:04 aio
drwxr-xr-x    2 root     root         6192 2002-06-12 06:40 amiraid
crw-r--r--    1 root     root      10, 134 1996-06-08 09:25 apm_bios
crw-rw----    1 root     root      36,   8 2001-03-26 09:04 arpd
drwxr-xr-x    2 root     root         1200 2002-05-20 11:41 ataraid
crw-rw----    1 root     sys       10,   3 1994-07-18 11:49 atibm
crw-rw----    1 root     root      10, 186 2001-03-26 09:04 atomicps
crw-rw----    1 root     sys       14,   4 1994-07-19 04:08 audio
crw-rw----    1 root     sys       14,  20 1994-07-19 04:08 audio1
brw-r-----    1 root     disk      29,   0 1995-02-16 09:38 aztcd
crw-r--r--    1 root     root      10, 128 1996-05-25 10:20 beep
drwxr-xr-x    2 root     root        49200 2002-06-04 05:52 cciss
lrwxrwxrwx    1 root     root            9 2003-03-10 14:50 cdrom -> /dev/scd0
brw-r-----    1 root     disk      24,   0 1994-07-19 04:07 cdu535
crw-rw----    1 root     root      67,   0 2001-03-26 09:04 cfs0
brw-r-----    1 root     disk      32,   0 1995-08-19 08:04 cm206cd
crw--w--w-    1 tink     tty        5,   1 2004-02-07 06:42 console
lrwxrwxrwx    1 root     root           11 2002-12-28 23:33 core -> /proc/kcore
lines 1-23/2499 0%

Quote:

Code:

[tink@athlon:~]$ ls -l /dev | wc -l
   441

[tink@athlon:~]$ ls -l /dev
total 0
lr-xr-xr-x    1 root     root           12 Feb  7  2004 agpgart -> misc/agpgart
lr-xr-xr-x    1 root     root           13 Feb  7  2004 apm_bios -> misc/apm_bios
lr-xr-xr-x    1 root     root           31 Feb  7 06:42 cdrom -> scsi/host1/bus0/target0/lun0/cd
drwxrwxr-x    1 root     dvd             0 Jan  1  1970 cdroms/
crw-------    1 root     root       5,   1 Feb  7 06:42 console
drwxr-xr-x    1 root     root            0 Jan  1  1970 cpu/
drwxr-xr-x    1 root     root            0 Jan  1  1970 cua/
lr-xr-xr-x    1 root     root            5 Feb  7 06:42 cua0 -> cua/0
drwxr-xr-x    1 root     root            0 Jan  1  1970 discs/
lr-xr-xr-x    1 root     root            9 Feb  7 06:42 dsp -> sound/dsp
lr-xr-xr-x    1 root     root           10 Feb  7 06:42 dsp1 -> sound/dsp1
lr-xr-xr-x    1 root     root           30 Feb  7  2004 dvd -> ide/host0/bus0/target1/lun0/cd

The thing is that with devfs, permissions get re-created
each time you boot. And if you haven't enabled saving
of permissions in /etc/devfsd.conf (or if you don't explicitly
set them in the same file) you're screwed :} (that is, you get
the effect you described). However, there may well be a different
(stupid, distro-specific) way to achieve the same outcome :)

Cheers,
Tink

Mistshadow · 02-06-2004, 08:53 PM

Thank you! Now I know what file to look at it to see if I can fix this.

Tinkster · 02-06-2004, 10:02 PM

Pleasure mate, and keep us informed. :)

Cheers,
Tink

P.S.: If it isn't too much effort I wouldn't mind
an affero! :}

Mistshadow · 02-07-2004, 02:30 AM

"File not found" and "file missing" - while I have it /etc open in my file manager looking at "boot.restore_permissions" it's saying it doesn't exist! Also sysV-init editor says the file is missing, even though it's on it's list.

Bug, you say? Quick, get the Raid! Lol. I've been trying to use an old copy of 8.2 while my SuSE 9 Pro is in the mail, but I guess I might as well give it up until it gets here. If it does the same thing to me, I'll be filing a bug report with SuSE.

*clicks affero*

/bin/bash · 02-09-2004, 05:16 AM

Usually if I change permissions in /dev I just do a restart of devfsd and the next time I boot the permissions are set.
service devfsd restart
or
/etc/init.d/devfsd restart