Because you are still connected to the Host, you have to make sure the LFS variable is still set to "/mnt/lfs", the files are still owned by the lfs user
Code:
chown -v lfs $LFS/tools
chown -v lfs $LFS/sources
and then change directories into /mnt/lfs. also make sure you have the .bashrc and .bash_profile set.
pretty much just re-run through 4.3-4.4 again without adding the lfs user again.