$ git clone -n https://src.fedoraproject.org/rpms/rust-memfd.git /var/lib/mock/f45-build-43260-801/root/chroot_tmpdir/scmroot/rust-memfd
Cloning into '/var/lib/mock/f45-build-43260-801/root/chroot_tmpdir/scmroot/rust-memfd'...
$ git fetch origin 87f2d57e693f4191bee710caa9ac7c608ed24f35:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/rust-memfd
 * [new ref]         87f2d57e693f4191bee710caa9ac7c608ed24f35 -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at 87f2d57 Update to version 0.6.6; Fixes RHBZ#2526825