i965: Handle non-zero texture buffer offsets in buffer object range calculation.

Otherwise the specified surface state will allow the GPU to access
memory up to BufferOffset bytes past the end of the buffer.  Found by
inspection.

v2: Protect against out-of-range BufferOffset (Nanley).
Cc: mesa-stable@lists.freedesktop.org
Reviewed-by: Nanley Chery <nanley.g.chery@intel.com>

diff --git a/src/mesa/drivers/dri/i965/brw_wm_surface_state.c b/src/mesa/drivers/dri/i965/brw_wm_surface_state.c
index af629a17bfaef6d6c834689cc587364247f1dbb9..39e898243db4f038c3304d250f7ddbdddf9acac1 100644 (file)
--- a/src/mesa/drivers/dri/i965/brw_wm_surface_state.c
+++ b/src/mesa/drivers/dri/i965/brw_wm_surface_state.c
@@ -647,6 +647,7 @@ buffer_texture_range_size(struct brw_context *brw,
    const unsigned texel_size = _mesa_get_format_bytes(obj->_BufferObjectFormat);
    const unsigned buffer_size = (!obj->BufferObject ? 0 :
                                  obj->BufferObject->Size);
+   const unsigned buffer_offset = MIN2(buffer_size, obj->BufferOffset);
 
    /* The ARB_texture_buffer_specification says:
     *
@@ -664,7 +665,8 @@ buffer_texture_range_size(struct brw_context *brw,
     * so that when ISL divides by stride to obtain the number of texels, that
     * texel count is clamped to MAX_TEXTURE_BUFFER_SIZE.
     */
-   return MIN3((unsigned)obj->BufferSize, buffer_size,
+   return MIN3((unsigned)obj->BufferSize,
+               buffer_size - buffer_offset,
                brw->ctx.Const.MaxTextureBufferSize * texel_size);
 }