[evolution-data-server/gnome-3-28] Bug 796174 - strcat() considered unsafe for buffer overflow

[Milan Crha <mcrha src gnome org>]

commit c52a659c84b7843cfb6e99ad9511d44c304fc3cb
Author: Milan Crha <mcrha redhat com>
Date:   Thu Jun 14 13:48:42 2018 +0200

    Bug 796174 - strcat() considered unsafe for buffer overflow

 .../backends/ldap/e-book-backend-ldap.c            | 46 ++++++++--------------
 1 file changed, 16 insertions(+), 30 deletions(-)
---
diff --git a/src/addressbook/backends/ldap/e-book-backend-ldap.c 
b/src/addressbook/backends/ldap/e-book-backend-ldap.c
index 0c8215811..5d6a0b72c 100644
--- a/src/addressbook/backends/ldap/e-book-backend-ldap.c
+++ b/src/addressbook/backends/ldap/e-book-backend-ldap.c
@@ -3583,8 +3583,7 @@ func_contains (struct _ESExp *f,
 
                if (!strcmp (propname, "x-evolution-any-field")) {
                        gint i;
-                       gint query_length;
-                       gchar *big_query;
+                       GString *big_query;
                        gchar *match_str;
                        if (one_star) {
                                g_free (str);
@@ -3597,14 +3596,8 @@ func_contains (struct _ESExp *f,
 
                        match_str = g_strdup_printf ("=*%s*)", str);
 
-                       query_length = 3; /* strlen ("(|") + strlen (")") */
-
-                       for (i = 0; i < G_N_ELEMENTS (prop_info); i++) {
-                               query_length += 1 /* strlen ("(") */ + strlen (prop_info[i].ldap_attr) + 
strlen (match_str);
-                       }
-
-                       big_query = g_malloc0 (query_length + 1);
-                       strcat (big_query, "(|");
+                       big_query = g_string_sized_new (G_N_ELEMENTS (prop_info) * 7);
+                       g_string_append (big_query, "(|");
                        for (i = 0; i < G_N_ELEMENTS (prop_info); i++) {
                                if ((prop_info[i].prop_type & PROP_TYPE_STRING) != 0 &&
                                    !(prop_info[i].prop_type & PROP_WRITE_ONLY) &&
@@ -3612,14 +3605,14 @@ func_contains (struct _ESExp *f,
                                     !(prop_info[i].prop_type & PROP_EVOLVE)) &&
                                    (ldap_data->bl->priv->calEntrySupported ||
                                     !(prop_info[i].prop_type & PROP_CALENTRY))) {
-                                       strcat (big_query, "(");
-                                       strcat (big_query, prop_info[i].ldap_attr);
-                                       strcat (big_query, match_str);
+                                       g_string_append (big_query, "(");
+                                       g_string_append (big_query, prop_info[i].ldap_attr);
+                                       g_string_append (big_query, match_str);
                                }
                        }
-                       strcat (big_query, ")");
+                       g_string_append (big_query, ")");
 
-                       ldap_data->list = g_list_prepend (ldap_data->list, big_query);
+                       ldap_data->list = g_list_prepend (ldap_data->list, g_string_free (big_query, FALSE));
 
                        g_free (match_str);
                }
@@ -3800,34 +3793,27 @@ func_exists (struct _ESExp *f,
 
                if (!strcmp (propname, "x-evolution-any-field")) {
                        gint i;
-                       gint query_length;
-                       gchar *big_query;
+                       GString *big_query;
                        gchar *match_str;
 
                        match_str = g_strdup ("=*)");
 
-                       query_length = 3; /* strlen ("(|") + strlen (")") */
-
-                       for (i = 0; i < G_N_ELEMENTS (prop_info); i++) {
-                               query_length += 1 /* strlen ("(") */ + strlen (prop_info[i].ldap_attr) + 
strlen (match_str);
-                       }
-
-                       big_query = g_malloc0 (query_length + 1);
-                       strcat (big_query, "(|");
+                       big_query = g_string_sized_new (G_N_ELEMENTS (prop_info) * 7);
+                       g_string_append (big_query, "(|");
                        for (i = 0; i < G_N_ELEMENTS (prop_info); i++) {
                                if (!(prop_info[i].prop_type & PROP_WRITE_ONLY) &&
                                    (ldap_data->bl->priv->evolutionPersonSupported ||
                                     !(prop_info[i].prop_type & PROP_EVOLVE)) &&
                                    (ldap_data->bl->priv->calEntrySupported ||
                                     !(prop_info[i].prop_type & PROP_CALENTRY))) {
-                                       strcat (big_query, "(");
-                                       strcat (big_query, prop_info[i].ldap_attr);
-                                       strcat (big_query, match_str);
+                                       g_string_append (big_query, "(");
+                                       g_string_append (big_query, prop_info[i].ldap_attr);
+                                       g_string_append (big_query, match_str);
                                }
                        }
-                       strcat (big_query, ")");
+                       g_string_append (big_query, ")");
 
-                       ldap_data->list = g_list_prepend (ldap_data->list, big_query);
+                       ldap_data->list = g_list_prepend (ldap_data->list, g_string_free (big_query, FALSE));
 
                        g_free (match_str);
                }