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Date:   Fri, 29 Apr 2022 17:30:50 +0200
From:   Willy Tarreau <w@1wt.eu>
To:     "Jason A. Donenfeld" <Jason@zx2c4.com>
Cc:     Netdev <netdev@vger.kernel.org>,
        David Miller <davem@davemloft.net>,
        Jakub Kicinski <kuba@kernel.org>,
        Eric Dumazet <edumazet@google.com>,
        Moshe Kol <moshe.kol@mail.huji.ac.il>,
        Yossi Gilad <yossi.gilad@mail.huji.ac.il>,
        Amit Klein <aksecurity@gmail.com>,
        LKML <linux-kernel@vger.kernel.org>
Subject: Re: [PATCH v2 net 3/7] tcp: resalt the secret every 10 seconds
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On Fri, Apr 29, 2022 at 04:48:52PM +0200, Jason A. Donenfeld wrote:
> On Thu, Apr 28, 2022 at 2:40 PM Willy Tarreau <w@1wt.eu> wrote:
> > @@ -101,10 +103,12 @@ u64 secure_ipv6_port_ephemeral(const __be32 *saddr, const __be32 *daddr,
> >                 struct in6_addr saddr;
> >                 struct in6_addr daddr;
> >                 __be16 dport;
> > +               unsigned int timeseed;
> 
> Also, does the struct packing (or lack thereof) lead to problems here?
> Uninitialized bytes might not make a stable hash.

Hmmm, I didn't notice, and I think you're right indeed. I did test in IPv6
without noticing any problem but it doesn't mean that the hash is perfectly
stable.

I'll send an update for this one, thank you!
Willy