tests: internal: fuzzers: add mp fuzzer

Signed-off-by: David Korczynski <[email protected]>

tests/internal/fuzzers/CMakeLists.txt

@@ -10,6 +10,7 @@ set(UNIT_TESTS_FILES
   input_fuzzer.c
   signv4_fuzzer.c
   flb_json_fuzzer.c
+  flb_mp_fuzzer.c
   filter_stdout_fuzzer.c
   parser_fuzzer.c
   parse_json_fuzzer.c

tests/internal/fuzzers/flb_mp_fuzzer.c

@@ -0,0 +1,55 @@
+/* -*- Mode: C; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 4 -*- */
+
+/*  Fluent Bit
+ *  ==========
+ *  Copyright (C) 2015-2023 The Fluent Bit Authors
+ *
+ *  Licensed under the Apache License, Version 2.0 (the "License");
+ *  you may not use this file except in compliance with the License.
+ *  You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ *  Unless required by applicable law or agreed to in writing, software
+ *  distributed under the License is distributed on an "AS IS" BASIS,
+ *  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ *  See the License for the specific language governing permissions and
+ *  limitations under the License.
+ */
+#include <stdlib.h>
+#include <stdint.h>
+#include <fluent-bit/flb_mem.h>
+#include <fluent-bit/flb_mp.h>
+
+#include "flb_fuzz_header.h"
+
+int LLVMFuzzerTestOneInput(unsigned char *data, size_t size)
+{
+    /* Set flb_malloc_mod to be fuzzer-data dependent */
+    if (size < 5) {
+        return 0;
+    }
+    flb_malloc_p = 0;
+    flb_malloc_mod = *(int*)data;
+    data += 4;
+    size -= 4;
+
+    /* Avoid division by zero for modulo operations */
+    if (flb_malloc_mod == 0) {
+        flb_malloc_mod = 1;
+    }
+
+    unsigned char decider = *data;
+    data++;
+    size--;
+
+    int out_records;
+    size_t processed_bytes;
+    if (decider % 2 == 0) {
+      flb_mp_validate_log_chunk(data, size, &out_records, &processed_bytes);
+    }
+    else if (decider % 2 == 1) {
+        flb_mp_validate_metric_chunk(data, size, &out_records, &processed_bytes);
+    }
+    return 0;
+}