From 112b02c32402d96fd7d526ab84877bb66dc12de4 Mon Sep 17 00:00:00 2001 From: Kenneth Graunke Date: Wed, 8 Feb 2012 05:08:23 -0800 Subject: vbo: Rework checking of 'end' against _MaxElement. This failed to take basevertex into account: If basevertex < 0: (end + basevertex) might actually be in-bounds while 'end' is not. We would have clamped in this case when we probably shouldn't. This could break application drawing. If basevertex > 0: 'end' might be in-bounds while (end + basevertex) might not. We would have failed to clamp in this place. There's a comment indicating the TNL module depends on max_index being in-bounds; if so, it would likely break horribly. Rather than trying to clamp correctly in the face of basevertex, simply delete the clamping code and indicate that we don't have a valid range. This causes _tnl_vbo_draw_prims to use vbo_get_minmax_indices() to compute the actual bounds, which is much safer. NOTE: This is a candidate for release branches. Signed-off-by: Kenneth Graunke Reviewed-by: Brian Paul Reviewed-by: Roland Scheidegger --- src/mesa/vbo/vbo_exec_array.c | 17 ++++++----------- 1 file changed, 6 insertions(+), 11 deletions(-) (limited to 'src/mesa/vbo') diff --git a/src/mesa/vbo/vbo_exec_array.c b/src/mesa/vbo/vbo_exec_array.c index 9c20296baba..809804f3b1c 100644 --- a/src/mesa/vbo/vbo_exec_array.c +++ b/src/mesa/vbo/vbo_exec_array.c @@ -859,6 +859,7 @@ vbo_exec_DrawRangeElementsBaseVertex(GLenum mode, GLint basevertex) { static GLuint warnCount = 0; + GLboolean index_bounds_valid = GL_TRUE; GET_CURRENT_CONTEXT(ctx); if (MESA_VERBOSE & VERBOSE_DRAW) @@ -911,16 +912,6 @@ vbo_exec_DrawRangeElementsBaseVertex(GLenum mode, end = MIN2(end, 0xffff); } - if (end >= ctx->Array.ArrayObj->_MaxElement) { - /* Set 'end' to the max possible legal value */ - assert(ctx->Array.ArrayObj->_MaxElement >= 1); - end = ctx->Array.ArrayObj->_MaxElement - 1; - - if (end < start) { - return; - } - } - if (0) { printf("glDraw[Range]Elements{,BaseVertex}" "(start %u, end %u, type 0x%x, count %d) ElemBuf %u, " @@ -930,13 +921,17 @@ vbo_exec_DrawRangeElementsBaseVertex(GLenum mode, basevertex); } + if ((int) start + basevertex < 0 || + end + basevertex >= ctx->Array.ArrayObj->_MaxElement) + index_bounds_valid = GL_FALSE; + #if 0 check_draw_elements_data(ctx, count, type, indices); #else (void) check_draw_elements_data; #endif - vbo_validated_drawrangeelements(ctx, mode, GL_TRUE, start, end, + vbo_validated_drawrangeelements(ctx, mode, index_bounds_valid, start, end, count, type, indices, basevertex, 1); } -- cgit v1.2.3