fuzz: add fuzzer for udev database

src/fuzz/fuzz-udev-database.c

@@ -0,0 +1,25 @@
+/* SPDX-License-Identifier: LGPL-2.1+ */
+
+#include "device-private.h"
+#include "fd-util.h"
+#include "fs-util.h"
+#include "fuzz.h"
+#include "tmpfile-util.h"
+
+int LLVMFuzzerTestOneInput(const uint8_t *data, size_t size) {
+        _cleanup_(sd_device_unrefp) sd_device *dev = NULL;
+        _cleanup_(unlink_tempfilep) char filename[] = "/tmp/fuzz-udev-database.XXXXXX";
+        _cleanup_fclose_ FILE *f = NULL;
+
+        if (!getenv("SYSTEMD_LOG_LEVEL"))
+                log_set_max_level(LOG_CRIT);
+
+        assert_se(fmkostemp_safe(filename, "r+", &f) == 0);
+        if (size != 0)
+                assert_se(fwrite(data, size, 1, f) == 1);
+
+        fflush(f);
+        assert_se(sd_device_new_from_syspath(&dev, "/sys/class/net/lo") >= 0);
+        (void) device_read_db_internal_filename(dev, filename);
+        return 0;
+}

src/fuzz/meson.build

@@ -97,6 +97,10 @@ fuzzers += [
           libshared],
          []],
 
+        [['src/fuzz/fuzz-udev-database.c'],
+         [libshared],
+         []],
+
         [['src/fuzz/fuzz-udev-rules.c'],
          [libudev_core,
           libudev_static,