YaGL: Avoid potential null pointer dereference in glGetUniformLocation()

Avoid passing a NULL name argument to function
yagl_gles2_program_get_uniform_location() as that function will
dereference the pointer without checking.

When the name argument is NULL make the function return value -1,
which according to OpenGL/GLES specification indicates that name
contains an invalid value/string.

This suppresses a SVACE warning:

* DEREF_AFTER_NULL: After having been compared to NULL value at yagl_gles2_calls.c:1096,
   pointer 'name' is passed as 2nd parameter in call to function 'yagl_gles2_program_get_uniform_location'
   at yagl_gles2_calls.c:1100, where it is dereferenced at yagl_gles2_program.c:373.
   [dereference] Variable 'name' is passed to function 'yagl_gles2_program_get_uniform_location'
    as 2nd parameter at GLESv2/yagl_gles2_calls.c:1100
   [null check] null check at GLESv2/yagl_gles2_calls.c:1096

Change-Id: Id4a4315e6c48eebf2c4047c158faa5bf54897e18
Signed-off-by: Sylwester Nawrocki <s.nawrocki@samsung.com>

1 files changed, 5 insertions, 2 deletions

diff --git a/GLESv2/yagl_gles2_calls.c b/GLESv2/yagl_gles2_calls.c
index 72d27ba..75a4e13 100644
--- a/GLESv2/yagl_gles2_calls.c
+++ b/GLESv2/yagl_gles2_calls.c
@@ -1093,10 +1093,13 @@ YAGL_API int glGetUniformLocation(GLuint program, const GLchar *name)
         goto out;
     }
 
-    if (name) {
-        YAGL_LOG_TRACE("getting uniform %s location", name);
+    if (!name) {
+        ret = -1;
+        goto out;
     }
 
+    YAGL_LOG_TRACE("getting uniform %s location", name);
+
     ret = yagl_gles2_program_get_uniform_location(program_obj, name);
 
 out: