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Subject: Re: [PATCH v4 3/3] x86 mm, x86 architecture (32-bit and 64-bit):
 arch/x86/mm/kaslr.c: Adds 64bits version of prandom_seed_state
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To:     David Keisar Schm <david.keisarschm@mail.huji.ac.il>
Cc:     linux-kernel@vger.kernel.org,
        Dave Hansen <dave.hansen@linux.intel.com>,
        Andy Lutomirski <luto@kernel.org>,
        Peter Zijlstra <peterz@infradead.org>,
        Thomas Gleixner <tglx@linutronix.de>,
        Ingo Molnar <mingo@redhat.com>, Borislav Petkov <bp@alien8.de>,
        x86@kernel.org, Jason@zx2c4.com, keescook@chromium.org,
        aksecurity@gmail.com, ilay.bahat1@gmail.com
References: <cover.1673470326.git.david.keisarschm@mail.huji.ac.il>
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From:   "H. Peter Anvin" <hpa@zytor.com>
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On 1/17/23 13:16, David Keisar Schm wrote:
> 
> Because (the way we understand this), Kees Cook prefers to keep the 
> original API, so that a fixed seed can be injected at will (for 
> debugging). Seehttps://lkml.org/lkml/2023/1/6/772 
> <https://lkml.org/lkml/2023/1/6/772>
> 

This bothers me, because with FG-KASLR is *exactly* when a bad PRNG will 
shine through.

	-hpa