svga: do primitive trimming in translate_indices()

The index translation code expects the number of indexes to be
consistent with the primitive type (ex: a multiple of 3 for
PIPE_PRIM_TRIANGLES).  If it's not, we can write out of bounds
in the destination buffer.

Fixes failed assertions in the pipebuffer debug code found with
Piglit primitive-restart-draw-mode test.

Cc: "10.0" <mesa-stable@lists.freedesktop.org>

Reviewed-by: José Fonseca <jfonseca@vmware.com>
This commit is contained in:
Brian Paul 2013-11-13 11:26:15 -07:00
parent 491d6397fc
commit 79984b9928

View file

@ -24,6 +24,7 @@
**********************************************************/
#include "util/u_inlines.h"
#include "util/u_prim.h"
#include "indices/u_indices.h"
#include "svga_cmd.h"
@ -37,17 +38,25 @@
static enum pipe_error
translate_indices(struct svga_hwtnl *hwtnl, struct pipe_resource *src,
unsigned offset, unsigned nr, unsigned index_size,
unsigned offset, unsigned prim, unsigned nr,
unsigned index_size,
u_translate_func translate, struct pipe_resource **out_buf)
{
struct pipe_context *pipe = &hwtnl->svga->pipe;
struct pipe_transfer *src_transfer = NULL;
struct pipe_transfer *dst_transfer = NULL;
unsigned size = index_size * nr;
unsigned size;
const void *src_map = NULL;
struct pipe_resource *dst = NULL;
void *dst_map = NULL;
/* Need to trim vertex count to make sure we don't write too much data
* to the dst buffer in the translate() call.
*/
u_trim_pipe_prim(prim, &nr);
size = index_size * nr;
dst = pipe_buffer_create(pipe->screen,
PIPE_BIND_INDEX_BUFFER, PIPE_USAGE_STATIC, size);
if (dst == NULL)
@ -180,7 +189,7 @@ svga_hwtnl_draw_range_elements(struct svga_hwtnl *hwtnl,
ret = translate_indices(hwtnl,
index_buffer,
start * index_size,
gen_nr, gen_size, gen_func, &gen_buf);
gen_prim, gen_nr, gen_size, gen_func, &gen_buf);
if (ret != PIPE_OK)
goto done;