linux-kernel - Re: [PATCH v2 net-next] net: poll/select low latency socket support

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]

Date:	Tue, 18 Jun 2013 02:08:30 -0700
From:	Eric Dumazet <eric.dumazet@...il.com>
To:	Eliezer Tamir <eliezer.tamir@...ux.intel.com>
Cc:	David Miller <davem@...emloft.net>, linux-kernel@...r.kernel.org,
	netdev@...r.kernel.org,
	Jesse Brandeburg <jesse.brandeburg@...el.com>,
	Don Skidmore <donald.c.skidmore@...el.com>,
	e1000-devel@...ts.sourceforge.net,
	Willem de Bruijn <willemb@...gle.com>,
	Ben Hutchings <bhutchings@...arflare.com>,
	Andi Kleen <andi@...stfloor.org>, HPA <hpa@...or.com>,
	Eilon Greenstien <eilong@...adcom.com>,
	Or Gerlitz <or.gerlitz@...il.com>,
	Amir Vadai <amirv@...lanox.com>,
	Alex Rosenbaum <alexr@...lanox.com>,
	Avner Ben Hanoch <avnerb@...lanox.com>,
	Or Kehati <ork@...lanox.com>, sockperf-dev@...glegroups.com,
	Eliezer Tamir <eliezer@...ir.org.il>
Subject: Re: [PATCH v2 net-next] net: poll/select low latency socket support

On Tue, 2013-06-18 at 11:58 +0300, Eliezer Tamir wrote:
> select/poll busy-poll support.
> 


>   */
> -static inline u64 ll_end_time(struct sock *sk)
> +static inline u64 ll_sk_end_time(struct sock *sk)
>  {
> -	u64 end_time = ACCESS_ONCE(sk->sk_ll_usec);
> -
> -	/* we don't mind a ~2.5% imprecision
> -	 * sk->sk_ll_usec is a u_int so this can't overflow
> -	 */
> -	end_time = (end_time << 10) + sched_clock();
> +	return (ACCESS_ONCE(sk->sk_ll_usec) << 10) + sched_clock();
> +}
>  

This is the fourth time you try to introduce an overflow in this code.

(same for ll_end_time())




--
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/