ipv4: Allow binding to non-local addresses if IP_TRANSPARENT is set

Setting IP_TRANSPARENT is not really useful without allowing non-local
binds for the socket. To make user-space code simpler we allow these
binds even if IP_TRANSPARENT is set but IP_FREEBIND is not.

Signed-off-by: Tóth László Attila <panther@balabit.hu>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/net/ipv4/af_inet.c b/net/ipv4/af_inet.c
index 8a3ac1f..1fbff5f 100644
--- a/net/ipv4/af_inet.c
+++ b/net/ipv4/af_inet.c
@@ -469,7 +469,7 @@
 	 */
 	err = -EADDRNOTAVAIL;
 	if (!sysctl_ip_nonlocal_bind &&
-	    !inet->freebind &&
+	    !(inet->freebind || inet->transparent) &&
 	    addr->sin_addr.s_addr != htonl(INADDR_ANY) &&
 	    chk_addr_ret != RTN_LOCAL &&
 	    chk_addr_ret != RTN_MULTICAST &&