Date:   Mon, 13 Mar 2023 10:41:27 +0100
From:   Michal =?utf-8?Q?Koutn=C3=BD?= <mkoutny@suse.com>
To:     Andrey Ryabinin <ryabinin.a.a@gmail.com>
Cc:     Dave Hansen <dave.hansen@intel.com>,
        the arch/x86 maintainers <x86@kernel.org>,
        LKML <linux-kernel@vger.kernel.org>,
        Alexander Potapenko <glider@google.com>,
        Andrey Konovalov <andreyknvl@gmail.com>,
        Dmitry Vyukov <dvyukov@google.com>,
        Vincenzo Frascino <vincenzo.frascino@arm.com>,
        kasan-dev@googlegroups.com, Kees Cook <keescook@chromium.org>,
        Thomas Garnier <thgarnie@google.com>
Subject: Re: KASLR vs. KASAN on x86
Message-ID: <20230313094127.3cqsnmngbdegbe6o@blackpad>
References: <299fbb80-e3ab-3b7c-3491-e85cac107930@intel.com>
 <CAPAsAGyG2_sUfb7aPSPuMatMraDbPCFKxhv2kSDkrV1XxQ8_bw@mail.gmail.com>
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On Wed, Mar 08, 2023 at 06:24:05PM +0100, Andrey Ryabinin <ryabinin.a.a@gmail.com> wrote:
> So the vmemmap_base and probably some part of vmalloc could easily end
> up in KASAN shadow.

Would it help to (conditionally) reduce vaddr_end to the beginning of
KASAN shadow memory?
(I'm not that familiar with KASAN, so IOW, would KASAN handle
randomized: linear mapping (__PAGE_OFFSET), vmalloc (VMALLOC_START) and
vmemmap (VMEMMAP_START) in that smaller range.)

Thanks,
Michal

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