make /dev/pci really readable
gurney_j at efn.org
Mon Jun 16 11:41:33 PDT 2003
Robert Watson wrote this message on Mon, Jun 16, 2003 at 13:54 -0400:
> On Mon, 16 Jun 2003, John-Mark Gurney wrote:
> > Does anyone have an objection to making /dev/pci really honor the
> > permissions, and giving normal users (or just group wheel) premission to
> > run pciconf -l. Right now the code requires the write bit set for any
> > operation.
> I seem to recall that there was a problem wherein user processes could
> cause cause unaligned accesses using /dev/pci. There's also some rather
again, I just proposed -l, not -r to become user readable. I know that -r
has problems. I've crashed the sparc box a number of times by specifing
pciconf -r pci1:5:0 0x0:0xf.
> odd use of useracc(), printf(), etc, in the ioctl code. I suspect this
well, do you mean odd use of printf as in providing diagnostics to catch
for useracc, it checks to make sure that various pointers passed to it
are either readable or writable. I don't see this as odd. Or is there
another better method of checking user data when accessing user space
other than a minor bug that could hit if there was more pci_devinfo's in
the list than pci_numdevs (which should never happen, but will prevent a
NULL deref), I didn't see anything wrong with -l.
> code needs some fairly thorough review and cleanup before we should reduce
> the level of privilege required to use the device (note that we make it
> world readable by default, so changes in the semantics of read permissions
> will affect all users in the system). Could you do that cleanup in the
> first pass, then revisit the permissions change?
sure, no problem.
John-Mark Gurney Voice: +1 415 225 5579
"All that I will do, has been done, All that I have, has not."
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