randr: stop clients from deleting immutable output properties

Immutable in randr means that clients are not able to alter the
property itself, they are only allowed to alter the property value.
This logically means that the property then should not be deleted
by the client either.

Signed-off-by: Luc Verhaegen <libv@skynet.be>
Reviewed-by: Rami Ylimäki <rami.ylimaki@vincit.fi>
Reviewed-by: Aaron Plattner <aplattner@nvidia.com>
Signed-off-by: Aaron Plattner <aplattner@nvidia.com>

1 files changed, 16 insertions, 3 deletions

diff --git a/randr/rrproperty.c b/randr/rrproperty.c
index 6ed24d3aa..d0a90203b 100644
--- a/randr/rrproperty.c
+++ b/randr/rrproperty.c
@@ -549,18 +549,31 @@ int
 ProcRRDeleteOutputProperty (ClientPtr client)
 {
     REQUEST(xRRDeleteOutputPropertyReq);
-    RROutputPtr	output;
-              
+    RROutputPtr		output;
+    RRPropertyPtr	prop;
+
     REQUEST_SIZE_MATCH(xRRDeleteOutputPropertyReq);
     UpdateCurrentTime();
     VERIFY_RR_OUTPUT(stuff->output, output, DixReadAccess);
-    
+
     if (!ValidAtom(stuff->property))
     {
 	client->errorValue = stuff->property;
 	return BadAtom;
     }
 
+    prop = RRQueryOutputProperty(output, stuff->property);
+    if (!prop)
+    {
+	client->errorValue = stuff->property;
+	return BadName;
+    }
+
+    if (prop->immutable)
+    {
+	client->errorValue = stuff->property;
+	return BadAccess;
+    }
 
     RRDeleteOutputProperty(output, stuff->property);
     return Success;