From 1140c228abe609750345a220535952ab6fd62a0f Mon Sep 17 00:00:00 2001
From: Philip Withnall <philip@tecnocode.co.uk>
Date: Wed, 24 Mar 2021 11:16:49 +0000
Subject: [PATCH] fuzzing: Add fuzz tests for functions which parse paths

Signed-off-by: Philip Withnall <pwithnall@endlessos.org>
---
 fuzzing/fuzz_canonicalize_filename.c | 19 +++++++++++++++++
 fuzzing/fuzz_paths.c                 | 32 ++++++++++++++++++++++++++++
 fuzzing/meson.build                  |  2 ++
 3 files changed, 53 insertions(+)
 create mode 100644 fuzzing/fuzz_canonicalize_filename.c
 create mode 100644 fuzzing/fuzz_paths.c

diff --git a/fuzzing/fuzz_canonicalize_filename.c b/fuzzing/fuzz_canonicalize_filename.c
new file mode 100644
index 000000000..86b323ef9
--- /dev/null
+++ b/fuzzing/fuzz_canonicalize_filename.c
@@ -0,0 +1,19 @@
+#include "fuzz.h"
+
+int
+LLVMFuzzerTestOneInput (const unsigned char *data, size_t size)
+{
+  unsigned char *nul_terminated_data = NULL;
+  gchar *canonicalized = NULL;
+
+  fuzz_set_logging_func ();
+
+  /* ignore @size (g_canonicalize_filename() doesn’t support it); ensure @data is nul-terminated */
+  nul_terminated_data = (unsigned char *) g_strndup ((const gchar *) data, size);
+  canonicalized = g_canonicalize_filename ((const gchar *) nul_terminated_data, "/");
+  g_free (nul_terminated_data);
+
+  g_free (canonicalized);
+
+  return 0;
+}
diff --git a/fuzzing/fuzz_paths.c b/fuzzing/fuzz_paths.c
new file mode 100644
index 000000000..1c866445f
--- /dev/null
+++ b/fuzzing/fuzz_paths.c
@@ -0,0 +1,32 @@
+#include "fuzz.h"
+
+int
+LLVMFuzzerTestOneInput (const unsigned char *data, size_t size)
+{
+  unsigned char *nul_terminated_data = NULL;
+  const gchar *skipped_root;
+  gchar *basename = NULL, *dirname = NULL;
+
+  fuzz_set_logging_func ();
+
+  /* ignore @size (none of the functions support it); ensure @data is nul-terminated */
+  nul_terminated_data = (unsigned char *) g_strndup ((const gchar *) data, size);
+
+  g_path_is_absolute ((const gchar *) nul_terminated_data);
+
+  skipped_root = g_path_skip_root ((const gchar *) nul_terminated_data);
+  g_assert (skipped_root == NULL || skipped_root >= (const gchar *) nul_terminated_data);
+  g_assert (skipped_root == NULL || skipped_root <= (const gchar *) nul_terminated_data + size);
+
+  basename = g_path_get_basename ((const gchar *) nul_terminated_data);
+  g_assert (strlen (basename) <= size);
+
+  dirname = g_path_get_dirname ((const gchar *) nul_terminated_data);
+  g_assert (strlen (dirname) <= size);
+
+  g_free (nul_terminated_data);
+  g_free (dirname);
+  g_free (basename);
+
+  return 0;
+}
diff --git a/fuzzing/meson.build b/fuzzing/meson.build
index a40321200..32e6c4269 100644
--- a/fuzzing/meson.build
+++ b/fuzzing/meson.build
@@ -1,5 +1,6 @@
 fuzz_targets = [
   'fuzz_bookmark',
+  'fuzz_canonicalize_filename',
   'fuzz_date_parse',
   'fuzz_date_time_new_from_iso8601',
   'fuzz_dbus_message',
@@ -9,6 +10,7 @@ fuzz_targets = [
   'fuzz_key',
   'fuzz_network_address_parse',
   'fuzz_network_address_parse_uri',
+  'fuzz_paths',
   'fuzz_uri_escape',
   'fuzz_uri_parse',
   'fuzz_uri_parse_params',