linux-kernel - Re: crypto: api - Fix use-after-free and race in crypto_spawn

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-ID: <20200416022502.GA18386@gondor.apana.org.au>
Date:   Thu, 16 Apr 2020 12:25:02 +1000
From:   Herbert Xu <herbert@...dor.apana.org.au>
To:     Eric Biggers <ebiggers@...nel.org>
Cc:     syzbot <syzbot+fc0674cde00b66844470@...kaller.appspotmail.com>,
        davem@...emloft.net, linux-crypto@...r.kernel.org,
        linux-kernel@...r.kernel.org, netdev@...r.kernel.org,
        syzkaller-bugs@...glegroups.com
Subject: Re: crypto: api - Fix use-after-free and race in crypto_spawn_alg

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@...dor.apana.org.au>
Home Page: http://gondor.apana.org.au/~herbert/
PGP Key: http://gondor.apana.org.au/~herbert/pubkey.txt