|
Message-ID: <CAPDLWs8iS_xU0uQHKU1h6HmqP-oqAfK1qAxDpis_JyPSGVGLug@mail.gmail.com> Date: Tue, 14 Feb 2017 13:34:38 +0530 From: Kaiwan N Billimoria <kaiwan@...wantech.com> To: Kees Cook <keescook@...omium.org> Cc: Laura Abbott <labbott@...hat.com>, "kernel-hardening@...ts.openwall.com" <kernel-hardening@...ts.openwall.com> Subject: Re: Merge in PAX_MEMORY_SANITIZE work from grsec to linux-next >> diff --git a/mm/page_poison.c b/mm/page_poison.c >> index 2e647c6..b45bc0a 100644 >> --- a/mm/page_poison.c >> +++ b/mm/page_poison.c >> @@ -49,6 +49,19 @@ struct page_ext_operations page_poisoning_ops = { >> .init = init_page_poisoning, >> }; >> >> +#ifdef CONFIG_MEMORY_SANITIZE >> +static int __init memory_sanitize_init(void) >> +{ >> + /* With 'memory sanitize' On, page poisoning Must be turned on */ >> + if (IS_ENABLED(CONFIG_MEMORY_SANITIZE)) { >> + want_page_poisoning = true; >> + __page_poisoning_enabled = true; >> + } >> + return 0; >> +} >> +early_initcall(memory_sanitize_init); >> +#endif > > The ifdef and the IS_ENABLED seem redundant to me. I'd drop the ifdef. An academic question perhaps- am not clear as to why the IS_ENABLED() is preferable to an #ifdef. I thought eliminating a runtime 'if' condition (by using an ifdef) is more optimal than the "if IS_ENABLED(foo)"? Or (probably) does the compiler optimize it out regardless (assuming that CONFIG_MEMORY_SANITIZE is not selected of course)? -Thanks, kaiwan.
Powered by blists - more mailing lists
Confused about mailing lists and their use? Read about mailing lists on Wikipedia and check out these guidelines on proper formatting of your messages.