On Mon, 2 Jul 2007, Andy Isaacson wrote:
> On Sat, Jun 30, 2007 at 12:03:07PM -0700, Davide Libenzi wrote:
> > I think the focus should be to find a case where under the currently
> > implemented policy for MAP_NOZERO, MAP_NOZERO represent a loss of security
> > WRT no MAP_NOZERO. I have not been able to find one yet, although Andy
> > found a potential one in the setuid+exec/ptrace race (fixed by a patch
> > that should IMO go in in any case).
> BTW, the ptrace variant of this issue is not a problem -- PTRACE_ATTACH
> running as newuid gets EPERM when trying to attach at /* here */ below.
> /* here */
> sys_setuid sets current->mm->dumpable = suid_dumpable, so unless the
> admin asked for it, there is no risk WRT PTRACE_ATTACH. However, this
> risk vector does need to be considered when implementing MAP_NOZERO.
Yes, I missed that. Ptrace is fine there. The 3 lines patch is still
needed for MAP_NOZERO though.
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to [email protected]
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/
[Index of Archives]
[Video 4 Linux]
[Linux for the blind]