linux-kernel - Re: [PATCH v3 35/75] x86/head/64: Build k/head64.c with -fno-stack-protector

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-ID: <20200603151857.GC23071@8bytes.org>
Date:   Wed, 3 Jun 2020 17:18:57 +0200
From:   Joerg Roedel <joro@...tes.org>
To:     Brian Gerst <brgerst@...il.com>
Cc:     the arch/x86 maintainers <x86@...nel.org>,
        "H. Peter Anvin" <hpa@...or.com>,
        Andy Lutomirski <luto@...nel.org>,
        Dave Hansen <dave.hansen@...ux.intel.com>,
        Peter Zijlstra <peterz@...radead.org>,
        Thomas Hellstrom <thellstrom@...are.com>,
        Jiri Slaby <jslaby@...e.cz>,
        Dan Williams <dan.j.williams@...el.com>,
        Tom Lendacky <thomas.lendacky@....com>,
        Juergen Gross <jgross@...e.com>,
        Kees Cook <keescook@...omium.org>,
        David Rientjes <rientjes@...gle.com>,
        Cfir Cohen <cfir@...gle.com>,
        Erdem Aktas <erdemaktas@...gle.com>,
        Masami Hiramatsu <mhiramat@...nel.org>,
        Mike Stunes <mstunes@...are.com>,
        Joerg Roedel <jroedel@...e.de>,
        Linux Kernel Mailing List <linux-kernel@...r.kernel.org>,
        kvm list <kvm@...r.kernel.org>,
        Linux Virtualization <virtualization@...ts.linux-foundation.org>
Subject: Re: [PATCH v3 35/75] x86/head/64: Build k/head64.c with
 -fno-stack-protector

On Tue, May 19, 2020 at 09:58:18AM -0400, Brian Gerst wrote:
> On Tue, Apr 28, 2020 at 11:28 AM Joerg Roedel <joro@...tes.org> wrote:

> The proper fix would be to initialize MSR_GS_BASE earlier.

That'll mean to initialize it two times during boot, as the first C
function with stack-protection is called before the kernel switches to
its high addresses (early_idt_setup call-path). But okay, I can do that.

On the other side, which value does the stack protector have in the early
boot code?


	Joerg