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cdrecord: behaves as if not suid root when it is, sorta.

Hi.  I've used cdrecord lots of times, but I've just recently run into
an odd problem.  When I use cdrecord as a non-root user, I get warning
messages that are not present if I use cdrecord as root:

cdrecord: Operation not permitted. WARNING: Cannot set RR-scheduler
cdrecord: Permission denied. WARNING: Cannot set priority using setpriority().
cdrecord: WARNING: This causes a high risk for buffer underruns.

>From searching the web/newsgroups, I can see that this is fairly
common -- cdrecord needs to be run as root, or as suid root.  However,
there are a few important differences.  First, I *don't* also get the
warning message of:

cdrecord: Operation not permitted. WARNING: Cannot do mlockall(2).

which usually comes with trying to run cdrecord as non-root and
without suid root access.  Second, cdrecord *does* proceed to the
write -- it doesn't say:

cdrecord: Read-only file system. Cannot open '/dev/cdrom'. Cannot open SCSI driver.
cdrecord: For possible targets try 'cdrecord -scanbus'. Make sure you are root.

and quit like it normally does if you try to run it as non-root and
without suid root access.  And finally, and most importantly,
my cdrecord *is* suid root:

stax:/usr/src-789> ls -al /usr/bin/cdrecord
-rws--s---    1 root     cdrom      314476 May 14 05:28 /usr/bin/cdrecord*

Other potentially useful info:

stax:/usr/src-790> groups
cmetzler cdrom floppy audio dip src video users

stax:/usr/src-791> ls -al /dev/scd0
brw-rw----    1 root     cdrom     11,   0 Aug 27  2002 /dev/scd0

stax:/usr/bin-805> dir /usr/bin/cdrdao
-rwsr-xr-x    1 root     root       532292 Oct 15  2002 /usr/bin/cdrdao*

Does anyone have a clue why I'm getting these warning messages?  What
have I missed?

Thanks much.


Chris Metzler			cmetzler@speakeasy.snip-me.net
		(remove "snip-me." to email)

"As a child I understood how to give; I have forgotten this grace since I
have become civilized." - Chief Luther Standing Bear

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