[Mesa-dev] [PATCH] mesa: don't crash in KHR_no_error uniform variants when location == -1

[Timothy Arceri]

On 14/05/17 01:39, Samuel Pitoiset wrote:
> Mmh, this can still crash if location is < -1 or greater than the number 
> of uniforms. How about:

Sorry my commit message went missing it should have something like:

"-1 is allowed by the spec so that inactive uniforms don't cause the app 
to throw an error."

In other words we need to not crash for that when running with no error 
enabled, but any of the paths that would normally hit an error we are 
free to crash on and need not waste any cpu checking for.

> 
> struct gl_uniform_storage *uni = NULL;
> if (_mesa_is_no_error_enabled(ctx)) {
>    if (location >= 0 && location < shProg->NumUniformRemapTable)
>      uni = shProg->UniformRemapTable[location];
>    if (!uni)
>      return;
>    ...
> } else {
>    ...
> }
> 
> On 05/13/2017 08:31 AM, Timothy Arceri wrote:
>> ---
>>   src/mesa/main/uniform_query.cpp | 3 +++
>>   1 file changed, 3 insertions(+)
>>
>> diff --git a/src/mesa/main/uniform_query.cpp 
>> b/src/mesa/main/uniform_query.cpp
>> index 0e02a76..5f38aa5 100644
>> --- a/src/mesa/main/uniform_query.cpp
>> +++ b/src/mesa/main/uniform_query.cpp
>> @@ -904,20 +904,23 @@ validate_uniform(GLint location, GLsizei count, 
>> const GLvoid *values,
>>   extern "C" void
>>   _mesa_uniform(GLint location, GLsizei count, const GLvoid *values,
>>                 struct gl_context *ctx, struct gl_shader_program *shProg,
>>                 enum glsl_base_type basicType, unsigned src_components)
>>   {
>>      unsigned offset;
>>      int size_mul = glsl_base_type_is_64bit(basicType) ? 2 : 1;
>>      struct gl_uniform_storage *uni;
>>      if (_mesa_is_no_error_enabled(ctx)) {
>> +      if (location == -1)
>> +         return;
>> +
>>         uni = shProg->UniformRemapTable[location];
>>         /* The array index specified by the uniform location is just the
>>          * uniform location minus the base location of of the uniform.
>>          */
>>         assert(uni->array_elements > 0 || location == 
>> (int)uni->remap_location);
>>         offset = location - uni->remap_location;
>>      } else {
>>         uni = validate_uniform(location, count, values, &offset, ctx, 
>> shProg,
>>                                basicType, src_components);
>>