MINOR: proxy: always properly reset the just freed default instance pointers

In proxy_free_defaults(); none of the free() calls was followed by a
pointer reset. Not only it's hard to figure if one of them is duplicated,
but this code started to call other functions which might or might not
rely on such just freed pointers. Let's reset them as they should be to
make sure there will never be any case of use-after-free. The 3 functions
called there were inspected and are all unaffected by this so this remains
safe to do right now.

diff --git a/src/proxy.c b/src/proxy.c
index a60d4530de94c703d2f417ca27ba5ae6722b043a..370e759e843e431ea13e35429294cea41bf56f89 100644 (file)
--- a/src/proxy.c
+++ b/src/proxy.c
@@ -1107,38 +1107,39 @@ void proxy_preset_defaults(struct proxy *defproxy)
  */
 void proxy_free_defaults(struct proxy *defproxy)
 {
-       free(defproxy->conf.file);
-       free(defproxy->check_command);
-       free(defproxy->check_path);
-       free(defproxy->cookie_name);
-       free(defproxy->rdp_cookie_name);
-       free(defproxy->dyncookie_key);
-       free(defproxy->cookie_domain);
-       free(defproxy->cookie_attrs);
-       free(defproxy->lbprm.arg_str);
-       free(defproxy->capture_name);
-       free(defproxy->monitor_uri);
-       free(defproxy->defbe.name);
-       free(defproxy->conn_src.iface_name);
-       free(defproxy->fwdfor_hdr_name);
-       defproxy->fwdfor_hdr_len = 0;
-       free(defproxy->orgto_hdr_name);
-       defproxy->orgto_hdr_len = 0;
-       free(defproxy->server_id_hdr_name);
-       defproxy->server_id_hdr_len = 0;
+       free(defproxy->conf.file); defproxy->conf.file = NULL;
+       free(defproxy->check_command); defproxy->check_command = NULL;
+       free(defproxy->check_path); defproxy->check_path = NULL;
+       free(defproxy->cookie_name); defproxy->cookie_name = NULL;
+       free(defproxy->rdp_cookie_name); defproxy->rdp_cookie_name = NULL;
+       free(defproxy->dyncookie_key); defproxy->dyncookie_key = NULL;
+       free(defproxy->cookie_domain); defproxy->cookie_domain = NULL;
+       free(defproxy->cookie_attrs);  defproxy->cookie_attrs = NULL;
+       free(defproxy->lbprm.arg_str); defproxy->lbprm.arg_str = NULL;
+       free(defproxy->capture_name); defproxy->capture_name = NULL;
+       free(defproxy->monitor_uri); defproxy->monitor_uri = NULL;
+       free(defproxy->defbe.name); defproxy->defbe.name = NULL;
+       free(defproxy->conn_src.iface_name); defproxy->conn_src.iface_name = NULL;
+       free(defproxy->fwdfor_hdr_name); defproxy->fwdfor_hdr_name = NULL; defproxy->fwdfor_hdr_len = 0;
+       free(defproxy->orgto_hdr_name); defproxy->orgto_hdr_name = NULL; defproxy->orgto_hdr_len = 0;
+       free(defproxy->server_id_hdr_name); defproxy->server_id_hdr_name = NULL; defproxy->server_id_hdr_len = 0;
 
        if (defproxy->conf.logformat_string != default_http_log_format &&
            defproxy->conf.logformat_string != default_tcp_log_format &&
-           defproxy->conf.logformat_string != clf_http_log_format)
+           defproxy->conf.logformat_string != clf_http_log_format) {
                free(defproxy->conf.logformat_string);
+               defproxy->conf.logformat_string = NULL;
+       }
 
-       if (defproxy->conf.logformat_sd_string != default_rfc5424_sd_log_format)
+       if (defproxy->conf.logformat_sd_string != default_rfc5424_sd_log_format) {
                free(defproxy->conf.logformat_sd_string);
+               defproxy->conf.logformat_sd_string = NULL;
+       }
 
-       free(defproxy->conf.uniqueid_format_string);
-       free(defproxy->conf.lfs_file);
-       free(defproxy->conf.lfsd_file);
-       free(defproxy->conf.uif_file);
+       free(defproxy->conf.uniqueid_format_string); defproxy->conf.uniqueid_format_string = NULL;
+       free(defproxy->conf.lfs_file); defproxy->conf.lfs_file = NULL;
+       free(defproxy->conf.lfsd_file); defproxy->conf.lfsd_file = NULL;
+       free(defproxy->conf.uif_file); defproxy->conf.uif_file = NULL;
        chunk_destroy(&defproxy->log_tag);
 
        free_email_alert(defproxy);