From 57a9c1ee478c5af8cc2f9ffe78b24917deebb1b3 Mon Sep 17 00:00:00 2001
From: =?utf8?q?Marek=20Ol=C5=A1=C3=A1k?= <marek.olsak@amd.com>
Date: Mon, 24 Feb 2020 20:46:02 -0500
Subject: [PATCH] glthread: fix a crash with incorrect glShaderSource
 parameters

Reviewed-by: Timothy Arceri <tarceri@itsqueeze.com>
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/3948>
---
 src/mesa/main/marshal.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/src/mesa/main/marshal.c b/src/mesa/main/marshal.c
index 9c9d6720878..b2935f63753 100644
--- a/src/mesa/main/marshal.c
+++ b/src/mesa/main/marshal.c
@@ -111,7 +111,7 @@ _mesa_marshal_ShaderSource(GLuint shader, GLsizei count,
       measure_ShaderSource_strings(count, string, length, length_tmp);
    size_t total_cmd_size = fixed_cmd_size + length_size + total_string_length;
 
-   if (total_cmd_size <= MARSHAL_MAX_CMD_SIZE) {
+   if (total_cmd_size <= MARSHAL_MAX_CMD_SIZE && count > 0) {
       struct marshal_cmd_ShaderSource *cmd =
          _mesa_glthread_allocate_command(ctx, DISPATCH_CMD_ShaderSource,
                                          total_cmd_size);
-- 
2.30.2