I have tested various kernels including 22.214.171.124 126.96.36.199 and 2.6.12-rc6 and am having unusual results regarding connect(). Earlier kernels do not return the same strange results.
I have tested numerous basic port scanners, including my own, and strangely ports which are NOT open are being reported as open. I have checked these ports by various means -- to be certain they are NOT open -- and in various runlevels; the results are the same.
The number of ports listed changes in size and they appear to be random. For example, on one scan ports 22, 3455, 4532 and 6236 will appear open; on another scan it might be 22, 3567, 3879, 3889, 6589 and 7374.
However, ports which ARE open do also appear as open alongside these "rogue" ports. I have also tested this on another system with the same results. It is also interesting to note that a basic TCP nmap scan does not return these unusual results.
Enclosed is example code that produces these results on the named kernels and systems.
main (int argc, char **argv)
int sd, result, server_port;
*struct* hostent *he;
*struct* sockaddr_in servaddr;