Commit 0724a7c3 authored by Ulf Magnusson's avatar Ulf Magnusson Committed by Masahiro Yamada
Browse files

kconfig: Don't leak main menus during parsing 



If a 'mainmenu' entry appeared in the Kconfig files, two things would
leak:

	- The 'struct property' allocated for the default "Linux Kernel
	  Configuration" prompt.

	- The string for the T_WORD/T_WORD_QUOTE prompt after the
	  T_MAINMENU token, allocated on the heap in zconf.l.

To fix it, introduce a new 'no_mainmenu_stmt' nonterminal that matches
if there's no 'mainmenu' and adds the default prompt. That means the
prompt only gets allocated once regardless of whether there's a
'mainmenu' statement or not, and managing it becomes simple.

Summary from Valgrind on 'menuconfig' (ARCH=x86) before the fix:

	LEAK SUMMARY:
	   definitely lost: 344,568 bytes in 14,352 blocks
	   ...

Summary after the fix:

	LEAK SUMMARY:
	   definitely lost: 344,440 bytes in 14,350 blocks
	   ...

Signed-off-by: default avatarUlf Magnusson <ulfalizer@gmail.com>
Signed-off-by: default avatarMasahiro Yamada <yamada.masahiro@socionext.com>
parent bc28fe1d

scripts/kconfig/zconf.y

+24 −9
Original line number Diff line number Diff line
@@ -109,7 +109,27 @@ static struct menu *current_menu, *current_entry; 
%%

input: nl start | start;



start: mainmenu_stmt stmt_list | stmt_list;

start: mainmenu_stmt stmt_list | no_mainmenu_stmt stmt_list;



/* mainmenu entry */



mainmenu_stmt: T_MAINMENU prompt nl

{

	menu_add_prompt(P_MENU, $2, NULL);

};



/* Default main menu, if there's no mainmenu entry */



no_mainmenu_stmt: /* empty */

{

	/*

	 * Hack: Keep the main menu title on the heap so we can safely free it

	 * later regardless of whether it comes from the 'prompt' in

	 * mainmenu_stmt or here

	 */

	menu_add_prompt(P_MENU, strdup("Linux Kernel Configuration"), NULL);

};





stmt_list:

	  /* empty */
@@ -352,13 +372,6 @@ if_block: 
	| if_block choice_stmt

;



/* mainmenu entry */



mainmenu_stmt: T_MAINMENU prompt nl

{

	menu_add_prompt(P_MENU, $2, NULL);

};



/* menu entry */



menu: T_MENU prompt T_EOL
@@ -507,6 +520,7 @@ word_opt: /* empty */ { $$ = NULL; } 


void conf_parse(const char *name)

{

	const char *tmp;

	struct symbol *sym;

	int i;
@@ -514,7 +528,6 @@ void conf_parse(const char *name) 


	sym_init();

	_menu_init();

	rootmenu.prompt = menu_add_prompt(P_MENU, "Linux Kernel Configuration", NULL);



	if (getenv("ZCONF_DEBUG"))

		zconfdebug = 1;
@@ -524,8 +537,10 @@ void conf_parse(const char *name) 
	if (!modules_sym)

		modules_sym = sym_find( "n" );



	tmp = rootmenu.prompt->text;

	rootmenu.prompt->text = _(rootmenu.prompt->text);

	rootmenu.prompt->text = sym_expand_string_value(rootmenu.prompt->text);

	free((char*)tmp);



	menu_finalize(&rootmenu);

	for_all_symbols(i, sym) {

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