From mboxrd@z Thu Jan  1 00:00:00 1970
From: Jiri Slaby <jirislaby@gmail.com>
Subject: Re: [PATCH -next v2] unix stream: Fix use-after-free crashes
Date: Thu, 08 Sep 2011 09:56:01 +0200
Message-ID: <4E687511.3040107@gmail.com>
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Cc: "Yan, Zheng" <zheng.z.yan@intel.com>,
	Tim Chen <tim.c.chen@linux.intel.com>,
	"sedat.dilek@gmail.com" <sedat.dilek@gmail.com>,
	"Yan, Zheng" <yanzheng@21cn.com>,
	"netdev@vger.kernel.org" <netdev@vger.kernel.org>,
	"davem@davemloft.net" <davem@davemloft.net>,
	"sfr@canb.auug.org.au" <sfr@canb.auug.org.au>,
	"Shi, Alex" <alex.shi@intel.com>,
	Valdis Kletnieks <Valdis.Kletnieks@vt.edu>
To: Eric Dumazet <eric.dumazet@gmail.com>
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On 09/08/2011 09:11 AM, Eric Dumazet wrote:
> Le jeudi 08 septembre 2011 =C3=A0 14:22 +0800, Yan, Zheng a =C3=A9cri=
t :
>=20
>> I don't think so. unix_scm_to_skb() calls unix_attach_fds(), it
>> always duplicates scm->fp.=20
>=20
> What a mess. This code is a nightmare.
>=20
> Part of the mess comes from scm_destroy() and scm_release() duplicati=
on.
>=20
> We should have scm_destroy() only, as before, and NULLify scm->pid/cr=
ed
> in unix_scm_to_skb() when we steal references.

This patch works for me. I haven't tried the out_err fixup from the
followup, but I assume I won't spot a difference as those are fail path=
s
anyway...

thanks,
--=20
js