Re: [lwip-users] UDP server on LwIP socket falls into hard fault if input string, longer than 19 bytes

[Sergio R. Caprile]

> hard fault. I think it because of NULL pointer exception

Insted of thinking, put an assertion to verify that, and follow your
processor debugging instructions to understand the actual reason of the
hard fault.
Even your OS has a guide on that:
http://www.freertos.org/Debugging-Hard-Faults-On-Cortex-M-Microcontrollers.html

PS: I would honor and follow advice regarding memory allocation 
functions, if I was you and I was chasing a fault on some error that 
depends on the number of data being processed.