From mboxrd@z Thu Jan  1 00:00:00 1970
From: Dmitry Safonov <dima@arista.com>
Subject: Re: [PATCH] netlink: Don't shift with UB on nlk->ngroups
Date: Mon, 30 Jul 2018 20:50:29 +0100
Message-ID: <1532980229.2679.34.camel@arista.com>
References: <20180730173236.20968-1-dima@arista.com>
         <20180730.124330.538236571439983894.davem@davemloft.net>
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Cc: linux-kernel@vger.kernel.org, rong.a.chen@intel.com,
        0x7f454c46@gmail.com, herbert@gondor.apana.org.au,
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To: David Miller <davem@davemloft.net>
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On Mon, 2018-07-30 at 12:43 -0700, David Miller wrote:
> From: Dmitry Safonov <dima@arista.com>
> Date: Mon, 30 Jul 2018 18:32:36 +0100
> 
> > On i386 nlk->ngroups might be 32 or 0. Which leads to UB, resulting
> in
> > hang during boot.
> > Check for 0 ngroups and use (unsigned long long) as a type to
> shift.
> > 
> > Fixes: commit 7acf9d4237c46894e0fa0492dd96314a41742e84 ("netlink:
> Do not
> > subscribe to non-existent groups").
> 
> Please, in the future, format your Fixes: tag correctly.  No need
> to say the work "commit", please do not chop up the line no matter
> how long it is, and please provide 12 digits of SHA1_ID value, rather
> than the whole thing.

Oh, yeah, I have this in .gitconfig:
[core]
        abbrev = 12

But I was formatting this not on my laptop and have managed to mislook.
Sorry about "commit" and the breakage.

> > Reported-by: kernel test robot <rong.a.chen@intel.com>
> > Signed-off-by: Dmitry Safonov <dima@arista.com>
> 
> Applied, thank you.

Thank you.