netdev - Re: [PATCH 1/2] ipv6: do not hold route table lock when send ndisc probe

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 for Android: free password hash cracker in your pocket

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Date:	Mon, 20 Aug 2012 20:15:49 +0800
From:	Cong Wang <amwang@...hat.com>
To:	Debabrata Banerjee <dbavatar@...il.com>
Cc:	netdev@...r.kernel.org,
	"Banerjee, Debabrata" <dbanerje@...mai.com>,
	"David S. Miller" <davem@...emloft.net>,
	Hideaki YOSHIFUJI <yoshfuji@...ux-ipv6.org>,
	Patrick McHardy <kaber@...sh.net>
Subject: Re: [PATCH 1/2] ipv6: do not hold route table lock when send ndisc
 probe

On Fri, 2012-08-17 at 14:54 -0400, Debabrata Banerjee wrote:
> Well it get rids of the deadlock for sure, but I am not sure it
> doesn't break something else, one would have to know all of this code
> much better to tell. You'll notice read_unlock_bh(&table->tb6_lock)
> for the first lock in ip6_pol_route() has more in the critical section
> after the rt6_select() call, especially that rather scary BACKTRACK()
> macro.
> 

Yeah, I noticed that, ->tb6_lock seems to protect lookup of ->tb6_root,
not sure if 'rt' may still valid after retaking this lock... Hmm,
probably calling ndisc_send_ns() inside a work is a better approach.

I will update the patch.

Thanks!

--
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