[2.6.22-rc4] UDP's local port assignment not working correctly.

[Tetsuo Handa]

Hello.

Same local ports are assigned to multiple sockets.
The following program should print different local port number.

----- Start of program -----
#include <stdio.h>
#include <unistd.h>
#include <sys/socket.h>
#include <sys/types.h>
#include <netinet/in.h>

int main(int argc, char *argv[]) {
	struct sockaddr_in addr;
	socklen_t size = sizeof(addr);
	int server = socket(PF_INET, SOCK_DGRAM, 0), client = socket(PF_INET, SOCK_DGRAM, 0);
	addr.sin_family = AF_INET;
	addr.sin_addr.s_addr = htonl(INADDR_LOOPBACK);
	addr.sin_port = htons(0);
	
	printf("Server: Binding UDP 127.0.0.1 0 ... ");
	bind(server, (struct sockaddr *) &addr, sizeof(addr));
	getsockname(server, (struct sockaddr *) &addr, &size);
	printf("bound to port %d\n", ntohs(addr.sin_port));
	
	printf("Client: Connecting UDP 127.0.0.1 %d ... ", ntohs(addr.sin_port));
	connect(client, (struct sockaddr *) &addr, sizeof(addr));
	getsockname(client, (struct sockaddr *) &addr, &size);
	printf("bound to port %d\n", ntohs(addr.sin_port));
	
	return 0;
}
----- End of program -----

I told YOSHIFUJI Hideaki and he answered me that
this is a regression caused by changing UDP's hash search algorithm to 2-pass.

Thanks.
-
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/