Mesa (main): aux/primconvert: handle singular incomplete restarts

[GitLab Mirror]

Module: Mesa
Branch: main
Commit: bc345281ab95313c2e34fffbd993bd1fbfc016be
URL:    http://cgit.freedesktop.org/mesa/mesa/commit/?id=bc345281ab95313c2e34fffbd993bd1fbfc016be

Author: Mike Blumenkrantz <michael.blumenkrantz at gmail.com>
Date:   Mon Nov  1 12:48:39 2021 -0400

aux/primconvert: handle singular incomplete restarts

if no restart indices are found, this draw must be discarded to avoid
crashing later on

Fixes: 583070748cb ("util/primconvert: handle rewriting of prim-restart draws with unsupported primtype")

Reviewed-by: Jesse Natalie <jenatali at microsoft.com>
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/13630>

---

 src/gallium/auxiliary/indices/u_primconvert.c | 7 +++++--
 1 file changed, 5 insertions(+), 2 deletions(-)

diff --git a/src/gallium/auxiliary/indices/u_primconvert.c b/src/gallium/auxiliary/indices/u_primconvert.c
index 62956910aa8..5ce8dddfa1f 100644
--- a/src/gallium/auxiliary/indices/u_primconvert.c
+++ b/src/gallium/auxiliary/indices/u_primconvert.c
@@ -202,8 +202,11 @@ util_primconvert_draw_vbo(struct primconvert_context *pc,
                             &direct_draw_func);
          /* this should always be a direct translation */
          assert(new_draw.count == total_index_count);
-         /* step 3: allocate a temp buffer for an intermediate rewrite step */
-         rewrite_buffer = malloc(index_size * total_index_count);
+         /* step 3: allocate a temp buffer for an intermediate rewrite step
+          *         if no indices were found, this was a single incomplete restart and can be discarded
+          */
+         if (total_index_count)
+            rewrite_buffer = malloc(index_size * total_index_count);
          if (!rewrite_buffer) {
             if (src_transfer)
                pipe_buffer_unmap(pc->pipe, src_transfer);