Fix wrong parameter in ICMPv4Checksum

Author: bemarkt

stack_system.go

@@ -586,7 +586,7 @@ func (s *System) processIPv4ICMP(ipHdr header.IPv4, icmpHdr header.ICMPv4) error
 	sourceAddress := ipHdr.SourceAddr()
 	ipHdr.SetSourceAddr(ipHdr.DestinationAddr())
 	ipHdr.SetDestinationAddr(sourceAddress)
-	icmpHdr.SetChecksum(header.ICMPv4Checksum(icmpHdr, checksum.Checksum(icmpHdr.Payload(), 0)))
+	icmpHdr.SetChecksum(header.ICMPv4Checksum(icmpHdr[:header.ICMPv4MinimumSize], checksum.Checksum(icmpHdr.Payload(), 0)))
 	ipHdr.SetChecksum(0)
 	ipHdr.SetChecksum(^ipHdr.CalculateChecksum())
 	return nil