From: Tobias Stoeckmann <tobias@stoeckmann.org>
Date: Tue, 16 Sep 2025 08:58:28 +0200
Subject: fuzzing: Fix fuzz_special_dirs

Always NUL-terminate the data, which g_file_get_contents does as well.
This fixes unnecessary fuzzer warnings.

For further clarification of this requirement, rename the internally
used function.

Bug: https://gitlab.gnome.org/GNOME/glib/-/issues/3783
Origin: upstream, 2.86.1, commit:0bebad35cf212c759cf6859d171d0655b0d87310
---
 fuzzing/fuzz_special_dirs.c | 7 ++++++-
 glib/gutils.c               | 2 +-
 glib/gutilsprivate.c        | 4 ++--
 3 files changed, 9 insertions(+), 4 deletions(-)

diff --git a/fuzzing/fuzz_special_dirs.c b/fuzzing/fuzz_special_dirs.c
index db20e4f..2d88fdf 100644
--- a/fuzzing/fuzz_special_dirs.c
+++ b/fuzzing/fuzz_special_dirs.c
@@ -26,10 +26,13 @@ int
 LLVMFuzzerTestOneInput (const unsigned char *data, size_t size)
 {
   gchar *special_dirs[G_USER_N_DIRECTORIES] = { 0 };
+  unsigned char *nul_terminated_data = NULL;
 
   fuzz_set_logging_func ();
 
-  load_user_special_dirs_from_data ((const gchar *) data, "/dev/null", special_dirs);
+  nul_terminated_data = (unsigned char *) g_strndup ((const char *) data, size);
+
+  load_user_special_dirs_from_string ((const gchar *) nul_terminated_data, "/dev/null", special_dirs);
 
   /* Test directories and make sure that, if they exist, they are absolute. */
   for (GUserDirectory dir_type = G_USER_DIRECTORY_DESKTOP; dir_type < G_USER_N_DIRECTORIES; dir_type++)
@@ -39,5 +42,7 @@ LLVMFuzzerTestOneInput (const unsigned char *data, size_t size)
       g_free (dir);
     }
 
+  g_free (nul_terminated_data);
+
   return 0;
 }
diff --git a/glib/gutils.c b/glib/gutils.c
index df744c7..9a4f7a7 100644
--- a/glib/gutils.c
+++ b/glib/gutils.c
@@ -2287,7 +2287,7 @@ load_user_special_dirs (void)
     }
 
   home_dir = g_get_home_dir_unlocked ();
-  load_user_special_dirs_from_data ((const gchar *) data, home_dir, g_user_special_dirs);
+  load_user_special_dirs_from_string (data, home_dir, g_user_special_dirs);
 
   g_free (data);
   g_free (config_file);
diff --git a/glib/gutilsprivate.c b/glib/gutilsprivate.c
index 4b48f91..e74f80f 100644
--- a/glib/gutilsprivate.c
+++ b/glib/gutilsprivate.c
@@ -23,12 +23,12 @@
  * SOFTWARE.
  */
 static void
-load_user_special_dirs_from_data (const gchar *data, const gchar *home_dir, gchar **special_dirs)
+load_user_special_dirs_from_string (const gchar *string, const gchar *home_dir, gchar **special_dirs)
 {
   gchar **lines;
   gint n_lines, i;
 
-  lines = g_strsplit (data, "\n", -1);
+  lines = g_strsplit (string, "\n", -1);
   n_lines = g_strv_length (lines);
 
   for (i = 0; i < n_lines; i++)