$ git clone -n https://src.fedoraproject.org/rpms/rust-rustsec.git /var/lib/mock/f42-build-side-1-3581450-46829/root/chroot_tmpdir/scmroot/rust-rustsec
Cloning into '/var/lib/mock/f42-build-side-1-3581450-46829/root/chroot_tmpdir/scmroot/rust-rustsec'...
$ git fetch origin da08b1782913032fc4bfc5cf3ae08ef4f34fa3fa:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/rust-rustsec
 * [new ref]         da08b1782913032fc4bfc5cf3ae08ef4f34fa3fa -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at da08b17 Update to version 0.30.2; Fixes RHBZ#2338794