vnc: distiguish between ipv4/ipv6 omitted vs set to off

The VNC code for interpreting QemuOpts does not currently
distinguish between ipv4/ipv6 being omitted, and being
set to 'off', because historically the 'ipv4' and 'ipv6'
options were just flags which did not accept a value.

The upshot is that if someone runs

  $QEMU -vnc localhost:1,ipv6=off

QEMU still uses PF_UNSPEC and thus may still bind to IPv6,
when it should use PF_INET.

This is another instance of the problem previously fixed
for chardevs in

  commit b77e7c8e99f9ac726c4eaa2fc3461fd886017dc0
  Author: Paolo Bonzini <pbonzini@redhat.com>
  Date:   Mon Oct 12 15:35:16 2015 +0200

    qemu-sockets: fix conversion of ipv4/ipv6 JSON to QemuOpts

Reviewed-by: Eric Blake <eblake@redhat.com>
Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
Message-id: 1452518225-11751-6-git-send-email-berrange@redhat.com
Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>

1 files changed, 12 insertions, 6 deletions

diff --git a/ui/vnc.c b/ui/vnc.c
index 85e3462..339f8c3 100644
--- a/ui/vnc.c
+++ b/ui/vnc.c
@@ -3502,8 +3502,10 @@ void vnc_display_open(const char *id, Error **errp)
 
         const char *websocket = qemu_opt_get(opts, "websocket");
         int to = qemu_opt_get_number(opts, "to", 0);
-        bool has_ipv4 = qemu_opt_get_bool(opts, "ipv4", false);
-        bool has_ipv6 = qemu_opt_get_bool(opts, "ipv6", false);
+        bool has_ipv4 = qemu_opt_get(opts, "ipv4");
+        bool has_ipv6 = qemu_opt_get(opts, "ipv6");
+        bool ipv4 = qemu_opt_get_bool(opts, "ipv4", false);
+        bool ipv6 = qemu_opt_get_bool(opts, "ipv6", false);
 
         saddr = g_new0(SocketAddress, 1);
         if (websocket) {
@@ -3551,8 +3553,10 @@ void vnc_display_open(const char *id, Error **errp)
                 saddr->u.inet->has_to = true;
                 saddr->u.inet->to = to + 5900;
             }
-            saddr->u.inet->ipv4 = saddr->u.inet->has_ipv4 = has_ipv4;
-            saddr->u.inet->ipv6 = saddr->u.inet->has_ipv6 = has_ipv6;
+            saddr->u.inet->ipv4 = ipv4;
+            saddr->u.inet->has_ipv4 = has_ipv4;
+            saddr->u.inet->ipv6 = ipv6;
+            saddr->u.inet->has_ipv6 = has_ipv6;
 
             if (vs->ws_enabled) {
                 wsaddr->type = SOCKET_ADDRESS_KIND_INET;
@@ -3564,8 +3568,10 @@ void vnc_display_open(const char *id, Error **errp)
                     wsaddr->u.inet->has_to = true;
                     wsaddr->u.inet->to = to;
                 }
-                wsaddr->u.inet->ipv4 = wsaddr->u.inet->has_ipv4 = has_ipv4;
-                wsaddr->u.inet->ipv6 = wsaddr->u.inet->has_ipv6 = has_ipv6;
+                wsaddr->u.inet->ipv4 = ipv4;
+                wsaddr->u.inet->has_ipv4 = has_ipv4;
+                wsaddr->u.inet->ipv6 = ipv6;
+                wsaddr->u.inet->has_ipv6 = has_ipv6;
             }
         }
     } else {