mesa: check that uniform exists in glUniform* functions

Remap table for uniforms may contain empty entries when using explicit
uniform locations. If no active/inactive variable exists with given
location, remap table contains NULL.

v2: move remap table bounds check before existence check (Ian Romanick)

Signed-off-by: Tapani Pälli <tapani.palli@intel.com>
Tested-by: Erik Faye-Lund <kusmabite@gmail.com> (v1)
Reviewed-by: Ian Romanick <ian.d.romanick@intel.com>
Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=83574

diff --git a/src/mesa/main/uniform_query.cpp b/src/mesa/main/uniform_query.cpp
index 4cd2bca01e373b976e63af9d192635548f97e9b7..1592c9bfd24feb9220f3c5432ec73500affe08f1 100644 (file)
--- a/src/mesa/main/uniform_query.cpp
+++ b/src/mesa/main/uniform_query.cpp
@@ -226,6 +226,13 @@ validate_uniform_parameters(struct gl_context *ctx,
       return NULL;
    }
 
+   /* Check that the given location is in bounds of uniform remap table. */
+   if (location >= (GLint) shProg->NumUniformRemapTable) {
+      _mesa_error(ctx, GL_INVALID_OPERATION, "%s(location=%d)",
+                  caller, location);
+      return NULL;
+   }
+
    /* Page 82 (page 96 of the PDF) of the OpenGL 2.1 spec says:
     *
     *     "If any of the following conditions occur, an INVALID_OPERATION
@@ -239,19 +246,12 @@ validate_uniform_parameters(struct gl_context *ctx,
     *         - if count is greater than one, and the uniform declared in the
     *           shader is not an array variable,
     */
-   if (location < -1) {
+   if (location < -1 || !shProg->UniformRemapTable[location]) {
       _mesa_error(ctx, GL_INVALID_OPERATION, "%s(location=%d)",
                   caller, location);
       return NULL;
    }
 
-   /* Check that the given location is in bounds of uniform remap table. */
-   if (location >= (GLint) shProg->NumUniformRemapTable) {
-      _mesa_error(ctx, GL_INVALID_OPERATION, "%s(location=%d)",
-                 caller, location);
-      return NULL;
-   }
-
    /* If the driver storage pointer in remap table is -1, we ignore silently.
     *
     * GL_ARB_explicit_uniform_location spec says: