Propably you managed to mess up some setting that causes init to trap on a command expected to always succeed.
Are you able to go to maintanance mode (connect USB cable to a computer) or does the trap occur before maintanance console activation?

If you cannot activate maintanance mode, then you are in a bit trickier situation, since you propably need to boot a different kernel (not ubiboot since it always tries to read ubiboot.conf)

However, full flash is not required, not at all

• You could load up the MOSLO kernel and then telnet to the device, mount up the /dev/mmcblk0p1 and correct the problem in your ubiboot.conf
• You could temporarily flash the L2-fixed kernel, for example so that the device boots up to Harmattan, and then fix the problem in your ubiboot.conf