No subject

"An INVALID_VALUE error is generated if any of readoffset, writeoffset,
 or size are negative [...]"

Fixes oglconform's copybuffer/negative.CNNegativeValues test.

Signed-off-by: Kenneth Graunke <kenneth at whitecape.org>
---
 src/mesa/main/bufferobj.c |    6 ++++++
 1 file changed, 6 insertions(+)

diff --git a/src/mesa/main/bufferobj.c b/src/mesa/main/bufferobj.c
index 5415665..846260d 100644
--- a/src/mesa/main/bufferobj.c
+++ b/src/mesa/main/bufferobj.c
@@ -1360,6 +1360,12 @@ _mesa_CopyBufferSubData(GLenum readTarget, GLenum writeTarget,
       return;
    }
 
+   if (size < 0) {
+      _mesa_error(ctx, GL_INVALID_VALUE,
+                  "glCopyBufferSubData(writeOffset = %d)", (int) size);
+      return;
+   }
+
    if (readOffset + size > src->Size) {
       _mesa_error(ctx, GL_INVALID_VALUE,
                   "glCopyBufferSubData(readOffset + size = %d)",
-- 
1.7.10.4