On Mon, Jan 30, 2012 at 2:41 PM, Colin Walters <walters@xxxxxxxxxx> wrote: > On Mon, 2012-01-30 at 14:10 -0800, Andy Lutomirski wrote: >> On Mon, Jan 30, 2012 at 1:58 PM, Colin Walters <walters@xxxxxxxxxx> wrote: >> > On Mon, 2012-01-30 at 08:17 -0800, Andy Lutomirski wrote: >> >> Chroot can easily be used to subvert setuid programs. If no_new_privs, >> >> then setuid programs don't gain any privilege, so allow chroot. >> > >> > Is this needed/desired by anyone now, or are you just using it to "demo" >> > NO_NEW_PRIVS? I don't see it as very useful on its own, since in any >> > "container"-type chroot you really want /proc and /dev, and your patch >> > doesn't help with that. >> >> It's a demo, but it could still be useful for container-ish things. >> If something privileged sets up /proc, /sys, and /dev, then >> unprivileged code can chroot into the container. This would allow >> much simpler implementations of tools like schroot. > > What's the win if you still need a setuid binary? schroot (and my > linux-user chroot binary) can just as easily call chroot as they can > create bind mounts; I'm not buying a code complexity argument. You don't need a setuid binary. Just have an initscript set up the bind mounts. --Andy -- To unsubscribe from this list: send the line "unsubscribe linux-fsdevel" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
