Newbies using slashed in filesystem labels should get an appropriate message from fstab generator instead of just memory exhaustion message.
Please look at this one:
It looks like this was a bug that was fixed a few days after you reported this issue, git bisect found this commit:
Author: Dave Reisner
Date: Sun Oct 6 18:26:23 2013 -0400
shared/util: fix off-by-one error in tag_to_udev_node
Triggered false negatives when encoding a string which needed every
character to be escaped, e.g. "LABEL=/".