netdev - Re: [PATCH v2 net] bpf: do not use reciprocal divide

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: <20140115.170230.640619926492650356.davem@davemloft.net>
Date:	Wed, 15 Jan 2014 17:02:30 -0800 (PST)
From:	David Miller <davem@...emloft.net>
To:	eric.dumazet@...il.com
Cc:	heiko.carstens@...ibm.com, schwidefsky@...ibm.com,
	hannes@...essinduktion.org, netdev@...r.kernel.org,
	dborkman@...hat.com, darkjames-ws@...kjames.pl, mgherzan@...il.com,
	rmk+kernel@....linux.org.uk, matt@...abs.org
Subject: Re: [PATCH v2 net] bpf: do not use reciprocal divide

From: Eric Dumazet <eric.dumazet@...il.com>
Date: Wed, 15 Jan 2014 06:50:07 -0800

> From: Eric Dumazet <edumazet@...gle.com>
> 
> At first Jakub Zawadzki noticed that some divisions by reciprocal_divide
> were not correct. (off by one in some cases)
> http://www.wireshark.org/~darkjames/reciprocal-buggy.c
> 
> He could also show this with BPF:
> http://www.wireshark.org/~darkjames/set-and-dump-filter-k-bug.c
> 
> The reciprocal divide in linux kernel is not generic enough,
> lets remove its use in BPF, as it is not worth the pain with
> current cpus.
> 
> Signed-off-by: Eric Dumazet <edumazet@...gle.com>
> Reported-by: Jakub Zawadzki <darkjames-ws@...kjames.pl>

Applied and queued up for -stable, thanks Eric.
--
To unsubscribe from this list: send the line "unsubscribe netdev" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html