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Message-ID: <1535411336.3516.2.camel@megha-Z97X-UD7-TH>
Subject: Re: KASAN: use-after-free Read in sha512_ctx_mgr_resubmit
From:   Megha Dey <megha.dey@linux.intel.com>
To:     Herbert Xu <herbert@gondor.apana.org.au>
Cc:     Ard Biesheuvel <ard.biesheuvel@linaro.org>,
        Eric Biggers <ebiggers@kernel.org>,
        Tim Chen <tim.c.chen@linux.intel.com>,
        "David S. Miller" <davem@davemloft.net>,
        syzbot <syzbot+d5455bac3ba1ee9114e5@syzkaller.appspotmail.com>,
        "open list:HARDWARE RANDOM NUMBER GENERATOR CORE" 
        <linux-crypto@vger.kernel.org>,
        Linux Kernel Mailing List <linux-kernel@vger.kernel.org>,
        syzkaller-bugs <syzkaller-bugs@googlegroups.com>,
        the arch/x86 maintainers <x86@kernel.org>
Date:   Mon, 27 Aug 2018 16:08:56 -0700
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On Wed, 2018-08-22 at 14:20 +0800, Herbert Xu wrote:
> On Tue, Aug 21, 2018 at 02:43:56PM +0200, Ard Biesheuvel wrote:
> >
> > I agree. The code is obviously broken in a way that would have been
> > noticed if it were in wide use, and it is too complicated for mere
> > mortals to fix or maintain. I suggest we simply remove it for now, and
> > if anyone wants to reintroduce it, we can review the code *and* the
> > justification for the approach from scratch (in which case we should
> > consider factoring out the algo agnostics plumbing in a way that
> > allows it to be reused by other architectures as well)
> 
> I agree too.  Could one of you guys send me a patch to remove
> them?
> 

Hi,

We are working on a fix to solve these corner cases.

-Megha
> Thanks,