linux-kernel - Re: [patch v3] splice: fix race with page invalidation

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: <E1KOSbz-0007b6-0L@pomaz-ex.szeredi.hu>
Date:	Thu, 31 Jul 2008 09:30:11 +0200
From:	Miklos Szeredi <miklos@...redi.hu>
To:	jamie@...reable.org
CC:	miklos@...redi.hu, torvalds@...ux-foundation.org,
	jens.axboe@...cle.com, akpm@...ux-foundation.org,
	nickpiggin@...oo.com.au, linux-fsdevel@...r.kernel.org,
	linux-kernel@...r.kernel.org, linux-mm@...ck.org
Subject: Re: [patch v3] splice: fix race with page invalidation

On Thu, 31 Jul 2008, Jamie Lokier wrote:
> I'm more concerned by sendfile() users like Apache, Samba, FTPd.  In
> an earlier thread on this topic, I asked if the splice bug can also
> result in sendfile() sending blocks of zeros, when a file is truncated
> after it has been sent, and the answer was yes probably.
> 
> Not that I checked or anything.  But if it affects sendfile() it's a
> bigger deal - that has many users.

Nick also pointed out, that it also affects plain read(2), albeit only
with a tiny window.

But partial truncates are _rare_ (we don't even have a UNIX utility
for that ;), so in practice all this may not actually matter very
much.

Miklos
--
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/