Commit f98ee769 authored Jul 10, 2011 by Arnaud Lacombe Committed by Michal Marek Jul 13, 2011

kconfig/nconf: prevent segfault on empty menu



nconf does not check the validity of the current menu when help is
requested (with either <F2>, '?' 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 <nir.tzachar@gmail.com>
Cc: Andrej Gelenberg <andrej.gelenberg@udo.edu>
Reported-by: Andrej Gelenberg <andrej.gelenberg@udo.edu>
Signed-off-by: Arnaud Lacombe <lacombar@gmail.com>
Signed-off-by: Michal Marek <mmarek@suse.cz>

parent 54168578

scripts/kconfig/nconf.c

+6 −1

Original line number	Original line	Diff line number	Diff line
	@@ -1220,7 +1220,12 @@ static void conf_message_callback(const char *fmt, va_list ap)

	static void show_help(struct menu *menu)		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);		menu_get_ext_help(menu, &help);
	show_scroll_win(main_window, _(menu_get_prompt(menu)), str_get(&help));		show_scroll_win(main_window, _(menu_get_prompt(menu)), str_get(&help));
	str_free(&help);		str_free(&help);

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