linux-kernel - Re: [PATCH net-next] tcp: Return error instead of partial read for saved syn headers

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: <1431975679.621.40.camel@edumazet-glaptop2.roam.corp.google.com>
Date:	Mon, 18 May 2015 12:01:19 -0700
From:	Eric Dumazet <eric.dumazet@...il.com>
To:	Rick Jones <rick.jones2@...com>
Cc:	Eric B Munson <emunson@...mai.com>,
	David Miller <davem@...emloft.net>,
	Eric Dumazet <edumazet@...gle.com>,
	Alexey Kuznetsov <kuznet@....inr.ac.ru>,
	James Morris <jmorris@...ei.org>,
	Hideaki YOSHIFUJI <yoshfuji@...ux-ipv6.org>,
	Patrick McHardy <kaber@...sh.net>, netdev@...r.kernel.org,
	linux-kernel@...r.kernel.org
Subject: Re: [PATCH net-next] tcp: Return error instead of partial read for
 saved syn headers

On Mon, 2015-05-18 at 11:41 -0700, Rick Jones wrote:
> On 05/18/2015 11:35 AM, Eric B Munson wrote:
> > Currently the getsockopt() requesting the cached contents of the syn
> > packet headers will fail silently if the caller uses a buffer that is
> > too small to contain the requested data.  Rather than fail silently and
> > discard the headers, getsockopt() should return an error and report the
> > required size to hold the data.
> 
> Is there any chapter and verse on whether a "failed" getsockopt() may 
> alter the items passed to it?

This should be fine.

getsockopt() has two copyout to perform, the second one can fail.

We can not 'undo' the first one in a safe way.


--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/