diff --git a/CHANGELOG b/CHANGELOG
index 6bb566d..0f01ad3 100644
--- a/CHANGELOG
+++ b/CHANGELOG
@@ -2,6 +2,10 @@ version 2.79
 	Fix parsing of CNAME arguments, which are confused by extra spaces.
 	Thanks to Diego Aguirre for spotting the bug.
 
+	Where available, use IP_UNICAST_IF or IPV6_UNICAST_IF to bind
+	upstream servers to an interface, rather than SO_BINDTODEVICE.
+	Thanks to Beniamino Galvani for the patch.
+
 
 version 2.78
         Fix logic of appending ".<layer>" to PXE basename. Thanks to Chris
diff --git a/src/dnsmasq.h b/src/dnsmasq.h
index c30a2f1..563443e 100644
--- a/src/dnsmasq.h
+++ b/src/dnsmasq.h
@@ -1254,7 +1254,7 @@ void free_rfd(struct randfd *rfd);
 
 /* network.c */
 int indextoname(int fd, int index, char *name);
-int local_bind(int fd, union mysockaddr *addr, char *intname, int is_tcp);
+int local_bind(int fd, union mysockaddr *addr, char *intname, unsigned int ifindex, int is_tcp);
 int random_sock(int family);
 void pre_allocate_sfds(void);
 int reload_servers(char *fname);
diff --git a/src/forward.c b/src/forward.c
index 942b02d..c2c50ec 100644
--- a/src/forward.c
+++ b/src/forward.c
@@ -1551,7 +1551,7 @@ static int tcp_key_recurse(time_t now, int status, struct dns_header *header, si
 		  setsockopt(server->tcpfd, SOL_SOCKET, SO_MARK, &mark, sizeof(unsigned int));
 #endif	
 		
-		if (!local_bind(server->tcpfd,  &server->source_addr, server->interface, 1) ||
+		if (!local_bind(server->tcpfd,  &server->source_addr, server->interface, 0, 1) ||
 		    connect(server->tcpfd, &server->addr.sa, sa_len(&server->addr)) == -1)
 		  {
 		    close(server->tcpfd);
@@ -1847,7 +1847,7 @@ unsigned char *tcp_request(int confd, time_t now,
 			    setsockopt(last_server->tcpfd, SOL_SOCKET, SO_MARK, &mark, sizeof(unsigned int));
 #endif	
 		      
-			  if ((!local_bind(last_server->tcpfd,  &last_server->source_addr, last_server->interface, 1) ||
+			  if ((!local_bind(last_server->tcpfd,  &last_server->source_addr, last_server->interface, 0, 1) ||
 			       connect(last_server->tcpfd, &last_server->addr.sa, sa_len(&last_server->addr)) == -1))
 			    {
 			      close(last_server->tcpfd);
diff --git a/src/network.c b/src/network.c
index 622c787..7395cfd 100644
--- a/src/network.c
+++ b/src/network.c
@@ -1187,7 +1187,7 @@ int random_sock(int family)
 }
   
 
-int local_bind(int fd, union mysockaddr *addr, char *intname, int is_tcp)
+int local_bind(int fd, union mysockaddr *addr, char *intname, unsigned int ifindex, int is_tcp)
 {
   union mysockaddr addr_copy = *addr;
 
@@ -1204,7 +1204,25 @@ int local_bind(int fd, union mysockaddr *addr, char *intname, int is_tcp)
   
   if (bind(fd, (struct sockaddr *)&addr_copy, sa_len(&addr_copy)) == -1)
     return 0;
-    
+
+  if (!is_tcp && ifindex > 0)
+    {
+#if defined(IP_UNICAST_IF)
+      if (addr_copy.sa.sa_family == AF_INET)
+        {
+          uint32_t ifindex_opt = htonl(ifindex);
+          return setsockopt(fd, IPPROTO_IP, IP_UNICAST_IF, &ifindex_opt, sizeof(ifindex_opt)) == 0;
+        }
+#endif
+#if defined(HAVE_IPV6) && defined (IPV6_UNICAST_IF)
+      if (addr_copy.sa.sa_family == AF_INET6)
+        {
+          uint32_t ifindex_opt = htonl(ifindex);
+          return setsockopt(fd, IPPROTO_IPV6, IPV6_UNICAST_IF, &ifindex_opt, sizeof(ifindex_opt)) == 0;
+        }
+#endif
+    }
+
 #if defined(SO_BINDTODEVICE)
   if (intname[0] != 0 &&
       setsockopt(fd, SOL_SOCKET, SO_BINDTODEVICE, intname, IF_NAMESIZE) == -1)
@@ -1260,7 +1278,7 @@ static struct serverfd *allocate_sfd(union mysockaddr *addr, char *intname)
       return NULL;
     }
   
-  if (!local_bind(sfd->fd, addr, intname, 0) || !fix_fd(sfd->fd))
+  if (!local_bind(sfd->fd, addr, intname, ifindex, 0) || !fix_fd(sfd->fd))
     { 
       errsave = errno; /* save error from bind. */
       close(sfd->fd);