diff --git a/client/render/gl_deferred.cpp b/client/render/gl_deferred.cpp
index 7abffbe35..d672a2015 100644
--- a/client/render/gl_deferred.cpp
+++ b/client/render/gl_deferred.cpp
@@ -554,7 +554,7 @@ void GL_SetupWorldScenePass( void )
 
 void GL_DrawDeferredPass( void )
 {
-	if( !tr.defSceneShader || !tr.defLightShader )
+	if( !tr.defSceneShader[0] || !tr.defSceneShader[1] || !tr.defLightShader )
 		return; // oops!
 
 	GL_DEBUG_SCOPE();
diff --git a/client/render/gl_grass.cpp b/client/render/gl_grass.cpp
index 8c0af47b3..73346812f 100644
--- a/client/render/gl_grass.cpp
+++ b/client/render/gl_grass.cpp
@@ -1109,13 +1109,20 @@ R_GrassTextureForName
 find or add unique texture for grass
 ================
 */
-byte R_GrassTextureForName( const char *name )
+int R_GrassTextureForName( const char *name, byte *tex )
 {
-	byte i;
+	size_t i;
+
 	for( i = 0; i < GRASS_TEXTURES && grasstexs[i].name[0]; i++ )
 	{
 		if( !Q_stricmp( grasstexs[i].name, name ))
-			return i;	// found
+			goto end;	// found
+	}
+
+	if( i == GRASS_TEXTURES )
+	{
+		ALERT( at_warning, "limit of grass textures was exceeded %d\n", GRASS_TEXTURES );
+		return 1;
 	}
 
 	// allocate a new one
@@ -1128,7 +1135,9 @@ byte R_GrassTextureForName( const char *name )
 		grasstexs[i].gl_texturenum = tr.defaultTexture;
 	}
 
-	return i;
+end:
+	*tex = (byte)i;
+	return 0;
 }
 
 /*
@@ -1692,7 +1701,8 @@ void R_GrassInit( void )
 				continue;
 			}
 
-			entry.texture = R_GrassTextureForName( token );
+			if( R_GrassTextureForName( token, &entry.texture ))
+				break;
 
 			pfile = COM_ParseLine( pfile, token );
 			if( !pfile )
diff --git a/client/render/gl_lightmap.cpp b/client/render/gl_lightmap.cpp
index e123fc8f8..f7d87d021 100644
--- a/client/render/gl_lightmap.cpp
+++ b/client/render/gl_lightmap.cpp
@@ -129,6 +129,7 @@ static void LM_GoToNextPage( void )
 
 	if( lms->state != LM_DONE ) return; // current atlas not completed
 
+	// There may be overflow because type of current_lightmap_texture is byte(uint8_t).
 	if( ++tr.current_lightmap_texture == MAX_LIGHTMAPS )
 		HOST_ERROR( "MAX_LIGHTMAPS limit exceded\n" );
 }
@@ -753,4 +754,4 @@ void R_UpdateSurfaceParams( mstudiosurface_t *surf )
 	// check for lightmap modification
 	if( FBitSet( surf->flags, SURF_LM_UPDATE|SURF_DM_UPDATE ))
 		R_UpdateLightMap( surf );
-}
\ No newline at end of file
+}
diff --git a/client/render/gl_local.h b/client/render/gl_local.h
index b4d76090f..5c88e3687 100644
--- a/client/render/gl_local.h
+++ b/client/render/gl_local.h
@@ -519,7 +519,7 @@ typedef struct
 	CUtlArray<gl_state_t>	cached_state;
 
 	gl_lightmap_t	lightmaps[MAX_LIGHTMAPS];
-	byte		current_lightmap_texture;
+	uint32_t	current_lightmap_texture;
 	TextureHandle	packed_lights_texture;
 	TextureHandle	packed_planes_texture;
 	TextureHandle	packed_nodes_texture;