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Date:   Thu, 16 Apr 2020 12:25:02 +1000
From:   Herbert Xu <herbert@gondor.apana.org.au>
To:     Eric Biggers <ebiggers@kernel.org>
Cc:     syzbot <syzbot+fc0674cde00b66844470@syzkaller.appspotmail.com>,
        davem@davemloft.net, linux-crypto@vger.kernel.org,
        linux-kernel@vger.kernel.org, netdev@vger.kernel.org,
        syzkaller-bugs@googlegroups.com
Subject: Re: crypto: api - Fix use-after-free and race in crypto_spawn_alg
Message-ID: <20200416022502.GA18386@gondor.apana.org.au>
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On Wed, Apr 15, 2020 at 07:17:03PM -0700, Eric Biggers wrote:
> 
> Wouldn't it be a bit simpler to set 'target = NULL', remove 'shoot',
> and use 'if (target)' instead of 'if (shoot)'?

Yes it is simpler but it's actually semantically different because
the compiler doesn't know that spawn->alg cannot be NULL in this
case.

Thanks,
-- 
Email: Herbert Xu <herbert@gondor.apana.org.au>
Home Page: http://gondor.apana.org.au/~herbert/
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