vbo: fix out-of-bounds array access

The exec->vtx.inputs[] array was being written past its end.  This was
clobbering the following vbo_exec_context::eval state.  Probably not noticed
since evaluators and immediate mode rendering don't happen at the same time.

Fixed the loop in vbo_exec_vtx_init().
Changed the size of the vbo_exec_context::vtx.arrays[] array.
Added a bunch of debug-build assertions.

Issue found by Vinson Lee.

1 files changed, 4 insertions, 0 deletions

diff --git a/src/mesa/vbo/vbo_exec_draw.c b/src/mesa/vbo/vbo_exec_draw.c
index 0c258c535e0..f41d6294507 100644
--- a/src/mesa/vbo/vbo_exec_draw.c
+++ b/src/mesa/vbo/vbo_exec_draw.c
@@ -172,6 +172,7 @@ vbo_exec_bind_arrays( GLcontext *ctx )
          exec->vtx.inputs[attr] = &vbo->legacy_currval[attr];
       }
       for (attr = 0; attr < MAT_ATTRIB_MAX; attr++) {
+         ASSERT(attr + 16 < Elements(exec->vtx.inputs));
          exec->vtx.inputs[attr + 16] = &vbo->mat_currval[attr];
       }
       map = vbo->map_vp_none;
@@ -184,6 +185,7 @@ vbo_exec_bind_arrays( GLcontext *ctx )
        */
       for (attr = 0; attr < 16; attr++) {
          exec->vtx.inputs[attr] = &vbo->legacy_currval[attr];
+         ASSERT(attr + 16 < Elements(exec->vtx.inputs));
          exec->vtx.inputs[attr + 16] = &vbo->generic_currval[attr];
       }
       map = vbo->map_vp_arb;
@@ -212,6 +214,8 @@ vbo_exec_bind_arrays( GLcontext *ctx )
 
       if (exec->vtx.attrsz[src]) {
          /* override the default array set above */
+         ASSERT(attr < Elements(exec->vtx.inputs));
+         ASSERT(attr < Elements(exec->vtx.arrays)); /* arrays[] */
          exec->vtx.inputs[attr] = &arrays[attr];
 
          if (_mesa_is_bufferobj(exec->vtx.bufferobj)) {