Fix potential null pointer deref in net_stream.c
Fix potential null pointer deref in net_stream.c

alco90/soml,mytestbed/oml,lees0414/EUproject,lees0414/EUproject,mytestbed/oml,alco90/soml,mytestbed/oml,lees0414/EUproject,lees0414/EUproject,mytestbed/oml,mytestbed/oml,alco90/soml,alco90/soml,alco90/soml,lees0414/EUproject