The NB socket buffer is too short for NB1500 http, causing overwrite and crash

[helgerustad]

I use an NB1500 and sends a http request to fetch a web page. The response is larger than 512 byte. This causes a SW crash. The bug has been identified in NBSocketBuffer.cpp;

• In NBSocketBuffer.cpp a 512 byte read buffer is allocated: <malloc(NB_SOCKET_BUFFER_SIZE)>.
• The a read of 512 byte is requested: <MODEM.sendf("AT+USORD=%d,%d", socket, NB_SOCKET_BUFFER_SIZE);>.
• The library has previously set HEX mode with <AT+UDCONF=1,1>.
• The modem returns two characters per byte - up to 1024 bytes. The library does not check the length causing overrun and SW crash,

Changing the USORD command line to <MODEM.sendf("AT+USORD=%d,%d", socket, NB_SOCKET_BUFFER_SIZE/2);> is one way to correct the error.

[CptHolzschnauz]

i think with
#84
it's solved