transport: Fix _find_myself for kernel 6.9

Kernel 6.9 seems to have changed AF_NETLINK behavior slightly making
booth unable to start.

Previously it was expected only first item in
the message can be NLMSG_DONE or NLMSG_ERROR type. And it looks this was
true for Kernel < 6.9.

With kernel 6.9 this is no longer true, so any item can be type
NLMSG_DONE or NLMSG_ERROR.

Result was loop was never terminated and booth was waiting for more
messages from kernel which never arrived.

Solution is to change loop a bit so NLMSG_DONE, NLMSG_ERROR and
RTM_NEWADDR are handled correctly.

Signed-off-by: Jan Friesse <[email protected]>

src/transport.c

@@ -208,17 +208,16 @@ int _find_myself(int family, struct booth_site **mep, int fuzzy_allowed)
 			return 0;
 		}
 
-		h = (struct nlmsghdr *)rcvbuf;
-		if (h->nlmsg_type == NLMSG_DONE)
-			break;
-
-		if (h->nlmsg_type == NLMSG_ERROR) {
-			close(fd);
-			log_error("netlink socket recvmsg error");
-			return 0;
-		}
+		for (h = (struct nlmsghdr *)rcvbuf; NLMSG_OK(h, status); h = NLMSG_NEXT(h, status)) {
+			if (h->nlmsg_type == NLMSG_DONE)
+				goto out;
+
+			if (h->nlmsg_type == NLMSG_ERROR) {
+				close(fd);
+				log_error("netlink socket recvmsg error");
+				return 0;
+			}
 
-		while (NLMSG_OK(h, status)) {
 			if (h->nlmsg_type == RTM_NEWADDR) {
 				struct ifaddrmsg *ifa = NLMSG_DATA(h);
 				struct rtattr *tb[IFA_MAX+1];
@@ -271,10 +270,10 @@ int _find_myself(int family, struct booth_site **mep, int fuzzy_allowed)
 					}
 				}
 			}
-			h = NLMSG_NEXT(h, status);
 		}
 	}
 
+out:
 	close(fd);
 
 	if (!me)