Fixing json memory leak.

src/core/lib/json/json_reader.c

@@ -180,6 +180,13 @@ grpc_json_reader_status grpc_json_reader_run(grpc_json_reader *reader) {
           case GRPC_JSON_STATE_VALUE_NUMBER_WITH_DECIMAL:
           case GRPC_JSON_STATE_VALUE_NUMBER_ZERO:
           case GRPC_JSON_STATE_VALUE_NUMBER_EPM:
+            if (reader->depth == 0) {
+              return GRPC_JSON_PARSE_ERROR;
+            } else if ((c == '}') && !reader->in_object) {
+              return GRPC_JSON_PARSE_ERROR;
+            } else if ((c == ']') && !reader->in_array) {
+              return GRPC_JSON_PARSE_ERROR;
+            }
             success = (uint32_t)json_reader_set_number(reader);
             if (!success) return GRPC_JSON_PARSE_ERROR;
             json_reader_string_clear(reader);

test/core/json/fuzzer.c

@@ -67,11 +67,8 @@ void guard_free(void *vptr) {
   g_old_allocs.free_fn(ptr);
 }
 
-struct gpr_allocation_functions g_guard_allocs = {
-  guard_malloc,
-  guard_realloc,
-  guard_free
-};
+struct gpr_allocation_functions g_guard_allocs = {guard_malloc, guard_realloc,
+                                                  guard_free};
 
 int LLVMFuzzerTestOneInput(const uint8_t *data, size_t size) {
   char *s;