$ git clone -n https://src.fedoraproject.org/rpms/rust-memfd.git /var/lib/mock/f38-build-side-42-init-devel-1391783-30858/root/chroot_tmpdir/scmroot/rust-memfd
Cloning into '/var/lib/mock/f38-build-side-42-init-devel-1391783-30858/root/chroot_tmpdir/scmroot/rust-memfd'...
$ git fetch origin 4c1d4899dbd61b01e2cb2fee4c53357cf08a16a8:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/rust-memfd
 * [new ref]         4c1d4899dbd61b01e2cb2fee4c53357cf08a16a8 -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at 4c1d489 Update to version 0.6.4; Fixes RHBZ#2239516