Possible to become root within blink?

[wvdschel]

I'm trying to run a Linux chroot on Mac.

I've grabbed a stage3 Gentoo tarball built against musl, modified /etc/shadow, and used blink -C gentoo-musl/ gentoo-musl/bin/bashto get a shell in the chroot. This seems to work, however, I'm unable to obtain root permissions by using su -.\

Did I do something wrong with my shadow file, or is this not possible in blink?

[tkchia]

Hello @wvdschel,

This seems to work, however, I'm unable to obtain root permissions by using su -.

I guess, for this to work, one will need to modify Blink so that it can be installed, or at least run, as a setuid program — without creating too much of a security loophole.

On a non-emulated Linux system, su is normally installed with a setuid bit in its permissions:

$ ls -l /bin/su
-rwsr-xr-x 1 root root 55672 Feb 21  2022 /bin/su

The setuid bit, plus the fact that it is owned by root, are what give it the power to switch to another user id.

Thank you!