tests/fuzzer: add virgl_venus_fuzzer

v2: switch to C and atexit (suggested by Gert)

Signed-off-by: Chia-I Wu <olvaffe@gmail.com>
Reviewed-by: Yiwei Zhang <zzyiwei@chromium.org> (v1)
Reviewed-by: Ryan Neph <ryanneph@google.com> (v1)

tests/fuzzer/meson.build

@@ -31,3 +31,13 @@ virgl_fuzzer = executable(
    link_args : [ '-fsanitize=fuzzer' ],
    dependencies : [libvirglrenderer_dep, gallium_dep, epoxy_dep]
 )
+
+if with_venus
+   virgl_venus_fuzzer = executable(
+      'virgl_venus_fuzzer',
+      'virgl_venus_fuzzer.c',
+      c_args : [ '-fsanitize=fuzzer' ],
+      link_args : [ '-fsanitize=fuzzer' ],
+      dependencies : [libvirglrenderer_dep]
+   )
+endif

tests/fuzzer/virgl_venus_fuzzer.c

@@ -0,0 +1,92 @@
+/*
+ * Copyright 2021 Google LLC
+ * SPDX-License-Identifier: MIT
+ */
+
+#include <stdbool.h>
+#include <stddef.h>
+#include <stdint.h>
+#include <stdlib.h>
+
+#include "os/os_misc.h"
+#include "virglrenderer.h"
+#include "virglrenderer_hw.h"
+
+int
+LLVMFuzzerTestOneInput(const uint8_t *data, size_t size);
+
+struct fuzz_renderer {
+   bool initialized;
+};
+
+static void
+fuzz_atexit_callback(void)
+{
+   virgl_renderer_cleanup(NULL);
+}
+
+static void
+fuzz_debug_callback(UNUSED const char *fmt, UNUSED va_list ap)
+{
+   /* no logging */
+}
+
+static struct fuzz_renderer *
+fuzz_renderer_get(void)
+{
+   static struct fuzz_renderer renderer;
+   if (renderer.initialized)
+      return &renderer;
+
+   int ret =
+      virgl_renderer_init(NULL, VIRGL_RENDERER_VENUS | VIRGL_RENDERER_NO_VIRGL, NULL);
+   if (ret)
+      abort();
+
+   virgl_set_debug_callback(fuzz_debug_callback);
+
+   atexit(fuzz_atexit_callback);
+
+   renderer.initialized = true;
+   return &renderer;
+}
+
+static uint32_t
+fuzz_context_create(UNUSED struct fuzz_renderer *renderer)
+{
+   const uint32_t ctx_id = 1;
+   const char name[] = "virgl_venus_fuzzer";
+   int ret = virgl_renderer_context_create_with_flags(ctx_id, VIRGL_RENDERER_CAPSET_VENUS,
+                                                      sizeof(name), name);
+   if (ret)
+      abort();
+
+   return ctx_id;
+}
+
+static void
+fuzz_context_destroy(UNUSED struct fuzz_renderer *renderer, uint32_t ctx_id)
+{
+   virgl_renderer_context_destroy(ctx_id);
+}
+
+static void
+fuzz_context_submit(UNUSED struct fuzz_renderer *renderer,
+                    uint32_t ctx_id,
+                    const uint8_t *data,
+                    size_t size)
+{
+   virgl_renderer_submit_cmd((void *)data, ctx_id, size / 4);
+}
+
+int
+LLVMFuzzerTestOneInput(const uint8_t *data, size_t size)
+{
+   struct fuzz_renderer *renderer = fuzz_renderer_get();
+
+   const uint32_t ctx_id = fuzz_context_create(renderer);
+   fuzz_context_submit(renderer, ctx_id, data, size);
+   fuzz_context_destroy(renderer, ctx_id);
+
+   return 0;
+}