kernel 2.6.8. ioctl ("/dev/hdc", CDROM_SEND_PACKET, cmd)
commands that are failing as non-root, even when permission is granted
rwxrwxrwx to /dev/hdc, are, according to some debug info added to k3b:
GET CONFIGURATION (46)
error code: 0
sense key: NO SENSE (2)
asc: 0
ascq: 0
and:
MODE SELECT (55)
error code: 0
sense key: NO SENSE (2)
asc: 0
ascq: 0
the result is that k3b cannot determine that the drive exists, therefore
it cannot use it even though cdrecord might actually work.
as root, the following errors occur:
MODE SELECT (46)
errorcode: 70
sense key: ILLEGAL REQUEST (5)
asc: 26
ascq: 0
READ DVD STRUCTURE (ad)
errorcode: 70
sense key: NOT READY (2)
asc: 3a
ascq: 0
presumably it can be concluded that the GET CONFIGURATION ioctl command
is the one at fault.
... what gives?
l.
--
--
Truth, honesty and respect are rare commodities that all spring from
the same well: Love. If you love yourself and everyone and everything
around you, funnily and coincidentally enough, life gets a lot better.
--
<a href="http://lkcl.net"> lkcl.net </a> <br />
<a href="mailto:[email protected]"> [email protected] </a> <br />
On Mon, Oct 04 2004, Luke Kenneth Casson Leighton wrote:
> kernel 2.6.8. ioctl ("/dev/hdc", CDROM_SEND_PACKET, cmd)
please search the archives, this has been discussed extensively over the
last month. frankly, I don't know how you were even able to miss it :)
--
Jens Axboe
Luke Kenneth Casson Leighton <[email protected]> writes:
> kernel 2.6.8. ioctl ("/dev/hdc", CDROM_SEND_PACKET, cmd)
>
> commands that are failing as non-root, even when permission is granted
> rwxrwxrwx to /dev/hdc, are, according to some debug info added to k3b:
>
> GET CONFIGURATION (46)
> error code: 0
> sense key: NO SENSE (2)
> asc: 0
> ascq: 0
>
> and:
>
> MODE SELECT (55)
> error code: 0
> sense key: NO SENSE (2)
> asc: 0
> ascq: 0
>
> the result is that k3b cannot determine that the drive exists, therefore
> it cannot use it even though cdrecord might actually work.
>
>
> as root, the following errors occur:
>
> MODE SELECT (46)
> errorcode: 70
> sense key: ILLEGAL REQUEST (5)
> asc: 26
> ascq: 0
>
> READ DVD STRUCTURE (ad)
> errorcode: 70
> sense key: NOT READY (2)
> asc: 3a
> ascq: 0
>
> presumably it can be concluded that the GET CONFIGURATION ioctl command
> is the one at fault.
>
> ... what gives?
CDROM_SEND_PACKET calls down to sg_io, which calls verify_command,
which will not permit anyone but root to use any unrecognised
commands. GET CONFIGURATION does not seems to be one of those
recognised. This check for unrecognised commands is a fairly recent
addition, IIRC.
On Mon, Oct 04 2004, Sean Neakums wrote:
> CDROM_SEND_PACKET calls down to sg_io, which calls verify_command,
> which will not permit anyone but root to use any unrecognised
> commands. GET CONFIGURATION does not seems to be one of those
> recognised. This check for unrecognised commands is a fairly recent
> addition, IIRC.
2.6.8 didn't have any command granularity, you must be root to issue any
comand there.
--
Jens Axboe
Jens Axboe <[email protected]> writes:
> On Mon, Oct 04 2004, Sean Neakums wrote:
>> CDROM_SEND_PACKET calls down to sg_io, which calls verify_command,
>> which will not permit anyone but root to use any unrecognised
>> commands. GET CONFIGURATION does not seems to be one of those
>> recognised. This check for unrecognised commands is a fairly recent
>> addition, IIRC.
>
> 2.6.8 didn't have any command granularity, you must be root to issue any
> comand there.
I was looking at 2.6.8.1 when I wrote the above, although it's
possible my eye skipped over something.
verify_command certainly seems to do the check:
http://lxr.linux.no/source/drivers/block/scsi_ioctl.c?v=2.6.8.1#L113
And it looks the same in the 2.6.8 tree I have here, too.
(Not trying to be an ass, just concerned about my reading comprehension.)
On Mon, Oct 04 2004, Sean Neakums wrote:
> Jens Axboe <[email protected]> writes:
>
> > On Mon, Oct 04 2004, Sean Neakums wrote:
> >> CDROM_SEND_PACKET calls down to sg_io, which calls verify_command,
> >> which will not permit anyone but root to use any unrecognised
> >> commands. GET CONFIGURATION does not seems to be one of those
> >> recognised. This check for unrecognised commands is a fairly recent
> >> addition, IIRC.
> >
> > 2.6.8 didn't have any command granularity, you must be root to issue any
> > comand there.
>
> I was looking at 2.6.8.1 when I wrote the above, although it's
> possible my eye skipped over something.
>
> verify_command certainly seems to do the check:
>
> http://lxr.linux.no/source/drivers/block/scsi_ioctl.c?v=2.6.8.1#L113
>
> And it looks the same in the 2.6.8 tree I have here, too.
You are right, it was added before, my recollection of the events
apparently isn't so good either. You are right in that GET_CONFIGURATION
was added later, post 2.6.8 release.
> (Not trying to be an ass, just concerned about my reading comprehension.)
:-)
--
Jens Axboe
On Mon, Oct 04, 2004 at 02:30:03PM +0100, Sean Neakums wrote:
> > ... what gives?
>
> CDROM_SEND_PACKET calls down to sg_io, which calls verify_command,
> which will not permit anyone but root to use any unrecognised
> commands. GET CONFIGURATION does not seems to be one of those
> recognised.
oh, right, i didn't think of checking that.
so if i just add that command, everything works hunky-dory.
well, i'll try it!
l.
--
--
Truth, honesty and respect are rare commodities that all spring from
the same well: Love. If you love yourself and everyone and everything
around you, funnily and coincidentally enough, life gets a lot better.
--
<a href="http://lkcl.net"> lkcl.net </a> <br />
<a href="mailto:[email protected]"> [email protected] </a> <br />
On Mon, Oct 04, 2004 at 02:49:39PM +0100, Sean Neakums wrote:
> Jens Axboe <[email protected]> writes:
>
> > On Mon, Oct 04 2004, Sean Neakums wrote:
> >> CDROM_SEND_PACKET calls down to sg_io, which calls verify_command,
> >> which will not permit anyone but root to use any unrecognised
> >> commands. GET CONFIGURATION does not seems to be one of those
> >> recognised. This check for unrecognised commands is a fairly recent
> >> addition, IIRC.
> >
> > 2.6.8 didn't have any command granularity, you must be root to issue any
> > comand there.
>
> I was looking at 2.6.8.1 when I wrote the above, although it's
> possible my eye skipped over something.
ah yes now i have found the issue i have a confession to make,
i'm actually running 2.6.8.1-selinux1.
i didn't want to mention that in case it was selinux that was the
problem :)
l.
On Mon, Oct 04, 2004 at 02:59:37PM +0200, Jens Axboe wrote:
> On Mon, Oct 04 2004, Luke Kenneth Casson Leighton wrote:
> > kernel 2.6.8. ioctl ("/dev/hdc", CDROM_SEND_PACKET, cmd)
>
> please search the archives, this has been discussed extensively over the
> last month. frankly, I don't know how you were even able to miss it :)
by not subscribing to the list, and searching for things as-and-when.
... i _did_ do a google search first, though, i promise!
"linux kernel cdrom ioctl CDROM_SEND_PACKET" gave this:
http://www.cs.helsinki.fi/linux/linux-kernel/2003-13/0617.html
which isn't exactly this month...
l.