$ git clone -n https://src.fedoraproject.org/rpms/subnetcalc.git /var/lib/mock/f43-build-59164372-6571403/root/chroot_tmpdir/scmroot/subnetcalc
Cloning into '/var/lib/mock/f43-build-59164372-6571403/root/chroot_tmpdir/scmroot/subnetcalc'...
$ git fetch origin 264b979ecd5dad99382685a049ece1228e815ead:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/subnetcalc
 * [new ref]         264b979ecd5dad99382685a049ece1228e815ead -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at 264b979 Update to 2.6.4