linux-kernel - Re: KASAN vs. boot-time switching between 4- and 5-level paging

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: <20170711170332.wlaudicepkg35dmm@node.shutemov.name>
Date:   Tue, 11 Jul 2017 20:03:32 +0300
From:   "Kirill A. Shutemov" <kirill@...temov.name>
To:     Andrey Ryabinin <aryabinin@...tuozzo.com>
Cc:     Andy Lutomirski <luto@...nel.org>,
        Dmitry Vyukov <dvyukov@...gle.com>,
        Alexander Potapenko <glider@...gle.com>,
        "Kirill A. Shutemov" <kirill.shutemov@...ux.intel.com>,
        Linus Torvalds <torvalds@...ux-foundation.org>,
        Andrew Morton <akpm@...ux-foundation.org>,
        "x86@...nel.org" <x86@...nel.org>,
        Thomas Gleixner <tglx@...utronix.de>,
        Ingo Molnar <mingo@...hat.com>,
        "H. Peter Anvin" <hpa@...or.com>, Andi Kleen <ak@...ux.intel.com>,
        Dave Hansen <dave.hansen@...el.com>,
        linux-arch <linux-arch@...r.kernel.org>,
        "linux-mm@...ck.org" <linux-mm@...ck.org>,
        LKML <linux-kernel@...r.kernel.org>,
        kasan-dev <kasan-dev@...glegroups.com>
Subject: Re: KASAN vs. boot-time switching between 4- and 5-level paging

On Tue, Jul 11, 2017 at 07:45:48PM +0300, Andrey Ryabinin wrote:
> On 07/11/2017 06:15 PM, Andrey Ryabinin wrote:
> > 
> > I reproduced this, and this is kasan bug:
> > 
> >    │0xffffffff84864897 <x86_early_init_platform_quirks+5>   mov    $0xffffffff83f1d0b8,%rdi 
> >    │0xffffffff8486489e <x86_early_init_platform_quirks+12>  movabs $0xdffffc0000000000,%rax 
> >    │0xffffffff848648a8 <x86_early_init_platform_quirks+22>  push   %rbp
> >    │0xffffffff848648a9 <x86_early_init_platform_quirks+23>  mov    %rdi,%rdx  
> >    │0xffffffff848648ac <x86_early_init_platform_quirks+26>  shr    $0x3,%rdx
> >    │0xffffffff848648b0 <x86_early_init_platform_quirks+30>  mov    %rsp,%rbp
> >   >│0xffffffff848648b3 <x86_early_init_platform_quirks+33>  mov    (%rdx,%rax,1),%al
> > 
> > we crash on the last move which is a read from shadow
> 
> 
> Ughh, I forgot about phys_base.

Thanks! Works for me.

Can use your Signed-off-by for a [cleaned up version of your] patch?


-- 
 Kirill A. Shutemov