netdev - Re: [net-next PATCH] igb: update adapter stats when reading /proc/net/dev.

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: <1286312479.2593.35.camel@edumazet-laptop>
Date:	Tue, 05 Oct 2010 23:01:19 +0200
From:	Eric Dumazet <eric.dumazet@...il.com>
To:	Jesper Dangaard Brouer <hawk@...x.dk>
Cc:	"David S. Miller" <davem@...emloft.net>, netdev@...r.kernel.org,
	Jeff Kirsher <jeffrey.t.kirsher@...el.com>
Subject: Re: [net-next PATCH] igb: update adapter stats when reading
 /proc/net/dev.

Le mardi 05 octobre 2010 à 17:19 +0200, Eric Dumazet a écrit :
> Le mardi 05 octobre 2010 à 16:53 +0200, Jesper Dangaard Brouer a écrit :
> 
> > Its already racy, because "ethtool -S" reads out the stats immediately,
> > and thus races with the timer.
> > 
> > See: igb_ethtool.c
> >  igb_get_ethtool_stats() invoke igb_update_stats(adapter);
> > 
> 
> You would be surprised how many bugs are waiting to be found and
> fixed ;)
> 
> 

I took a look at igb stats, and it appears they also are racy on 32bit
arches. igb uses u64 counters, with no synchronization between
producers(writers) and consumers(readers).

Some fixes are needed ;)



--
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