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Date:   Tue, 24 Apr 2018 08:51:04 -0600
From:   Tycho Andersen <tycho@tycho.ws>
To:     Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>
Cc:     ebiggers3@gmail.com, dhowells@redhat.com, keyrings@vger.kernel.org,
        linux-security-module@vger.kernel.org,
        linux-kernel@vger.kernel.org, kernel-hardening@lists.openwall.com,
        jmorris@namei.org, serge@hallyn.com, Jason@zx2c4.com
Subject: Re: [PATCH 1/3] big key: get rid of stack array allocation
Message-ID: <20180424145104.GC3125@cisco>
References: <20180424010321.14739-1-tycho@tycho.ws>
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 <201804242346.FHI69745.SQMHFVOOFLFOJt@I-love.SAKURA.ne.jp>
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On Tue, Apr 24, 2018 at 11:46:38PM +0900, Tetsuo Handa wrote:
> Tycho Andersen wrote:
> > > > +	if (unlikely(crypto_aead_ivsize(big_key_aead) != GCM_AES_IV_SIZE)) {
> > > > +		WARN(1, "big key algorithm changed?");
> 
> Please avoid using WARN() WARN_ON() etc.
> syzbot would catch it and panic() due to panic_on_warn == 1.

But it is really a programming bug in this case (and it seems better
than BUG()...). Isn't this exactly the sort of case we want to catch?

Tycho