[gimp] app, libgimp: UTF-8 validate all string arguments and return values

[Michael Natterer <mitch src gnome org>]

commit fab806089ab3c78b920738d8f1b6844aaec61178
Author: Michael Natterer <mitch gimp org>
Date:   Mon Aug 19 13:11:02 2019 +0200

    app, libgimp: UTF-8 validate all string arguments and return values
    
    The only way for a plug-in to prevent this is now using
    GIMP_PARAM_NO_VALIDATE.

 app/pdb/gimpprocedure.c | 34 ++++++++++++++++++++++++++++++++++
 libgimp/gimpprocedure.c | 34 ++++++++++++++++++++++++++++++++++
 2 files changed, 68 insertions(+)
---
diff --git a/app/pdb/gimpprocedure.c b/app/pdb/gimpprocedure.c
index ebb00d72e7..bdc623946f 100644
--- a/app/pdb/gimpprocedure.c
+++ b/app/pdb/gimpprocedure.c
@@ -882,6 +882,40 @@ gimp_procedure_validate_args (GimpProcedure  *procedure,
               return FALSE;
             }
 
+          /*  UTT-8 validate all strings  */
+          if (G_PARAM_SPEC_TYPE (pspec) == G_TYPE_PARAM_STRING)
+            {
+              const gchar *string = g_value_get_string (arg);
+
+              if (string && ! g_utf8_validate (string, -1, NULL))
+                {
+                  if (return_vals)
+                    {
+                      g_set_error (error,
+                                   GIMP_PDB_ERROR,
+                                   GIMP_PDB_ERROR_INVALID_RETURN_VALUE,
+                                   _("Procedure '%s' returned an "
+                                     "invalid UTF-8 string for argument '%s'."),
+                                   gimp_object_get_name (procedure),
+                                   g_param_spec_get_name (pspec));
+                    }
+                  else
+                    {
+                      g_set_error (error,
+                                   GIMP_PDB_ERROR,
+                                   GIMP_PDB_ERROR_INVALID_ARGUMENT,
+                                   _("Procedure '%s' has been called with an "
+                                     "invalid UTF-8 string for argument '%s'."),
+                                   gimp_object_get_name (procedure),
+                                   g_param_spec_get_name (pspec));
+                    }
+
+                  g_value_unset (&string_value);
+
+                  return FALSE;
+                }
+            }
+
           g_value_unset (&string_value);
         }
     }
diff --git a/libgimp/gimpprocedure.c b/libgimp/gimpprocedure.c
index 4443881463..78e0ccd666 100644
--- a/libgimp/gimpprocedure.c
+++ b/libgimp/gimpprocedure.c
@@ -1507,6 +1507,40 @@ gimp_procedure_validate_args (GimpProcedure         *procedure,
               return FALSE;
             }
 
+          /*  UTT-8 validate all strings  */
+          if (G_PARAM_SPEC_TYPE (pspec) == G_TYPE_PARAM_STRING)
+            {
+              const gchar *string = g_value_get_string (arg);
+
+              if (string && ! g_utf8_validate (string, -1, NULL))
+                {
+                  if (return_vals)
+                    {
+                      g_set_error (error,
+                                   GIMP_PDB_ERROR,
+                                   GIMP_PDB_ERROR_INVALID_RETURN_VALUE,
+                                   _("Procedure '%s' returned an "
+                                     "invalid UTF-8 string for argument '%s'."),
+                                   gimp_procedure_get_name (procedure),
+                                   g_param_spec_get_name (pspec));
+                    }
+                  else
+                    {
+                      g_set_error (error,
+                                   GIMP_PDB_ERROR,
+                                   GIMP_PDB_ERROR_INVALID_ARGUMENT,
+                                   _("Procedure '%s' has been called with an "
+                                     "invalid UTF-8 string for argument '%s'."),
+                                   gimp_procedure_get_name (procedure),
+                                   g_param_spec_get_name (pspec));
+                    }
+
+                  g_value_unset (&string_value);
+
+                  return FALSE;
+                }
+            }
+
           g_value_unset (&string_value);
         }
     }