Re: exec and EXECSERVERS

2002-12-20 Thread Roland McGrath
> Well, I think that the exec server should remove EXECSERVERS, on the > ground that it's the exec server that knows about the feature too. That's what I was saying in the first place. ___ Bug-hurd mailing list [EMAIL PROTECTED] http://mail.gnu.org/mai

Re: exec and EXECSERVERS

2002-12-20 Thread Paul Jarc
Roland McGrath <[EMAIL PROTECTED]> wrote: >> Anyhow, the point is a good one with respect to environment variables, >> and perhaps we should enable EXECSERVERS with the suggested tweak, >> that it is off for secure exec and for euid!=ruid. > > EXECSERVERS has to be excised from the environment, not

Re: exec and EXECSERVERS

2002-12-20 Thread Thomas Bushnell, BSG
Roland McGrath <[EMAIL PROTECTED]> writes: > > Why is that? If it's programs that call setuid(getuid()) that have > > this responsibility (as the original poster suggested), then this is > > just fine. On the other hand, my vote is that it's the setuid program > > itself that always has the resp

Re: exec and EXECSERVERS

2002-12-20 Thread Roland McGrath
> Why is that? If it's programs that call setuid(getuid()) that have > this responsibility (as the original poster suggested), then this is > just fine. On the other hand, my vote is that it's the setuid program > itself that always has the responsibility. That is a new responsibility that ind

Re: exec and EXECSERVERS

2002-12-20 Thread Thomas Bushnell, BSG
Roland McGrath <[EMAIL PROTECTED]> writes: > > I thought there was some special Linux widget in the dynamic loader > > that we don't support. Maybe that's just long gone. > > You are thinking of ld.so.cache. Yes, that's right. > > Anyhow, the point is a good one with respect to environment var

Re: exec and EXECSERVERS

2002-12-20 Thread Roland McGrath
> I thought there was some special Linux widget in the dynamic loader > that we don't support. Maybe that's just long gone. You are thinking of ld.so.cache. > Anyhow, the point is a good one with respect to environment variables, > and perhaps we should enable EXECSERVERS with the suggested twea

Re: exec and EXECSERVERS

2002-12-20 Thread Thomas Bushnell, BSG
Roland McGrath <[EMAIL PROTECTED]> writes: > > > In Unix, if I run setuid program foo, and foo runs program bar, then > > > the dynamic loader, noticing that ruid!=euid, will ignore LD_PRELOAD, > > > etc., when loading bar. (Right?) This is because LD_PRELOAD is under > > > the control of a user

Re: exec and EXECSERVERS

2002-12-20 Thread Roland McGrath
> > In Unix, if I run setuid program foo, and foo runs program bar, then > > the dynamic loader, noticing that ruid!=euid, will ignore LD_PRELOAD, > > etc., when loading bar. (Right?) This is because LD_PRELOAD is under > > the control of a user different from the one whose privileges we have > >

Re: exec and EXECSERVERS

2002-12-20 Thread Thomas Bushnell, BSG
[EMAIL PROTECTED] (Paul Jarc) writes: > [EMAIL PROTECTED] (Thomas Bushnell, BSG) wrote: > > We don't want to change other execs, because there is no reason to > > think there is any kind of security implication for them. > > Why not? Doesn't ruid!=euid have the same implications as in Unix? > (I

Re: exec and EXECSERVERS

2002-12-20 Thread Paul Jarc
[EMAIL PROTECTED] (Thomas Bushnell, BSG) wrote: > We don't want to change other execs, because there is no reason to > think there is any kind of security implication for them. Why not? Doesn't ruid!=euid have the same implications as in Unix? (I.e., that a setuid program was executed, and no cod

Re: exec and EXECSERVERS

2002-12-20 Thread Thomas Bushnell, BSG
[EMAIL PROTECTED] (Paul Jarc) writes: > I agree - the kernel does not set uid=euid. (It preserves the old > uid, and sets the new euid according to the file's owner.) I was > saying something different: if there is a program running in a setuid > situation (i.e., its real uid is different from i

Re: exec and EXECSERVERS

2002-12-19 Thread Paul Jarc
[EMAIL PROTECTED] (Thomas Bushnell, BSG) wrote: > [EMAIL PROTECTED] (Paul Jarc) writes: >> I don't know this Hurd stuff very well (or at all, nearly), but in >> Unix terms, I'd say whatever code sets uid=euid (if any) in a setuid >> situation should take responsibility for clearing dangerous >> env

Re: exec and EXECSERVERS

2002-12-19 Thread Thomas Bushnell, BSG
[EMAIL PROTECTED] (Paul Jarc) writes: > I don't know this Hurd stuff very well (or at all, nearly), but in > Unix terms, I'd say whatever code sets uid=euid (if any) in a setuid > situation should take responsibility for clearing dangerous > environment variables (or any other attributes of the pr

Re: exec and EXECSERVERS

2002-12-19 Thread Paul Jarc
[EMAIL PROTECTED] (Thomas Bushnell, BSG) wrote: > Well, a setuid exec itself should disable EXECSERVERS. But the > environment variable might still get inherited, and seven layers of > fork/exec later, do something nasty. So that means that setuid exec > should in fact clear EXECSERVERS in the pa

Re: exec and EXECSERVERS

2002-12-19 Thread Thomas Bushnell, BSG
"Alfred M. Szmidt" <[EMAIL PROTECTED]> writes: >> What was the reason for disabling EXECSERVERS in exec? I think that >> it is quite an useful feature when debugging exec, or playing around >> with new features for it. > >This[1] thread might interest you. > >[1] http://mail

Re: exec and EXECSERVERS

2002-12-19 Thread Neal H. Walfield
> What was the reason for disabling EXECSERVERS in exec? I think that > it is quite an useful feature when debugging exec, or playing around > with new features for it. This[1] thread might interest you. [1] http://mail.gnu.org/pipermail/bug-hurd/2000-May/001211.html _

Re: exec and EXECSERVERS

2002-12-19 Thread Alfred M. Szmidt
> What was the reason for disabling EXECSERVERS in exec? I think that > it is quite an useful feature when debugging exec, or playing around > with new features for it. This[1] thread might interest you. [1] http://mail.gnu.org/pipermail/bug-hurd/2000-May/001211.html Interesting.

Re: exec and EXECSERVERS

2002-12-19 Thread Roland McGrath
> I think there were just bugs and rather than figure them out, we > commented it out. I think it would certainly be useful to turn it on > and make it work. There may have been bugs. There were also security concerns about an EXECSERVERS being inherited indirectly by setuid programs and the li

Re: exec and EXECSERVERS

2002-12-19 Thread Thomas Bushnell, BSG
"Alfred M. Szmidt" <[EMAIL PROTECTED]> writes: > What was the reason for disabling EXECSERVERS in exec? I think that > it is quite an useful feature when debugging exec, or playing around > with new features for it. I think there were just bugs and rather than figure them out, we commented it ou

exec and EXECSERVERS

2002-12-19 Thread Alfred M. Szmidt
What was the reason for disabling EXECSERVERS in exec? I think that it is quite an useful feature when debugging exec, or playing around with new features for it. ___ Bug-hurd mailing list [EMAIL PROTECTED] http://mail.gnu.org/mailman/listinfo/bug-hurd