Commit 4dc5d815 authored May 17, 2017 by Daniel P. Berrangé

sockets: don't block IPv4 clients when listening on "::"



When inet_parse() parses the hostname, it is forcing the
has_ipv6 && ipv6 flags if the address contains a ":". This
means that if the user had set the ipv4=on flag, to try to
restrict the listener to just ipv4, an error would not have
been raised.  eg

   -incoming tcp:[::]:9000,ipv4

should have raised an error because listening for IPv4
on "::" is a non-sensical combination. With this removed,
we now call getaddrinfo() on "::" passing PF_INET and
so getaddrinfo reports an error about the hostname being
incompatible with the requested protocol:

 qemu-system-x86_64: -incoming tcp:[::]:9000,ipv4: address resolution
    failed for :::9000: Address family for hostname not supported

Likewise it is explicitly setting the has_ipv4 & ipv4
flags when the address contains only digits + '.'. This
has no ill-effect, but also has no benefit, so is removed.

Acked-by: Gerd Hoffmann <kraxel@gmail.com>
Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Reviewed-by: Eric Blake <eblake@redhat.com>
Signed-off-by: Daniel P. Berrange <berrange@redhat.com>

parent 5e059be4

util/qemu-sockets.c

+0 −4

Original line number	Diff line number	Diff line
		@@ -618,16 +618,12 @@ int inet_parse(InetSocketAddress addr, const char str, Error **errp)
		error_setg(errp, "error parsing IPv6 address '%s'", str);
		return -1;
		}
		addr->ipv6 = addr->has_ipv6 = true;
		} else {
		/* hostname or IPv4 addr */
		if (sscanf(str, "%64[^:]:%32[^,]%n", host, port, &pos) != 2) {
		error_setg(errp, "error parsing address '%s'", str);
		return -1;
		}
		if (host[strspn(host, "0123456789.")] == '\0') {
		addr->ipv4 = addr->has_ipv4 = true;
		}
		}

		addr->host = g_strdup(host);