[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]
Message-ID: <CAGXu5jKctN4SQr4H-jPywEw4Te+ObVZSV0bUR5MLqu1ZrgNEBA@mail.gmail.com>
Date: Fri, 8 Feb 2019 13:28:02 -0800
From: Kees Cook <keescook@...omium.org>
To: Elena Reshetova <elena.reshetova@...el.com>
Cc: Kernel Hardening <kernel-hardening@...ts.openwall.com>, Andy Lutomirski <luto@...nel.org>,
Thomas Gleixner <tglx@...utronix.de>, Ingo Molnar <mingo@...hat.com>, Borislav Petkov <bp@...en8.de>,
Peter Zijlstra <peterz@...radead.org>
Subject: Re: [RFC PATCH] x86/entry/64: randomize kernel stack offset upon
system call
On Fri, Feb 8, 2019 at 4:16 AM Elena Reshetova
<elena.reshetova@...el.com> wrote:
> --- a/mm/usercopy.c
> +++ b/mm/usercopy.c
> @@ -37,7 +37,7 @@
> static noinline int check_stack_object(const void *obj, unsigned long len)
> {
> const void * const stack = task_stack_page(current);
> - const void * const stackend = stack + THREAD_SIZE;
> + const void * const stackend = (void *)task_top_of_stack(current);
> int ret;
>
> /* Object is not on the stack at all. */
It seems like having task_top_of_stack() would be a nice refactoring
to have regardless of this feature (and splitting out would make this
patch a bit easier to read too).
--
Kees Cook
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.
