From f98ee76955f883abf2ea2a5e5b43deab01734f47 Mon Sep 17 00:00:00 2001 From: Arnaud Lacombe Date: Sun, 10 Jul 2011 03:27:05 -0400 Subject: [PATCH] kconfig/nconf: prevent segfault on empty menu nconf does not check the validity of the current menu when help is requested (with either , '?' or 'h'). This leads to a NULL pointer dereference when an empty menu is encountered. The following reduced testcase exposes the problem: config DEP bool menu "FOO" config BAR bool "BAR" depends on DEP endmenu Issue will happen when entering menu "FOO" and requesting help. nconf is the only front-end which do not filter the validity of the current menu. Such filter can not really happen beforehand as other key which does not deals with the current menu might be entered by the user, so just bails out earlier if we encounter an invalid menu. Cc: Nir Tzachar Cc: Andrej Gelenberg Reported-by: Andrej Gelenberg Signed-off-by: Arnaud Lacombe Signed-off-by: Michal Marek --- scripts/kconfig/nconf.c | 7 ++++++- 1 file changed, 6 insertions(+), 1 deletion(-) diff --git a/scripts/kconfig/nconf.c b/scripts/kconfig/nconf.c index d55666d2dd85..d6345df1ce12 100644 --- a/scripts/kconfig/nconf.c +++ b/scripts/kconfig/nconf.c @@ -1220,7 +1220,12 @@ static void conf_message_callback(const char *fmt, va_list ap) static void show_help(struct menu *menu) { - struct gstr help = str_new(); + struct gstr help; + + if (!menu) + return; + + help = str_new(); menu_get_ext_help(menu, &help); show_scroll_win(main_window, _(menu_get_prompt(menu)), str_get(&help)); str_free(&help);