linux-kernel - Re: [PATCH next] netlink: prevent deadlock in ctrl

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] [day] [month] [year] [list]

Date:	Tue, 20 Aug 2013 22:31:17 +0300
From:	Sergey Senozhatsky <sergey.senozhatsky@...il.com>
To:	"Berg, Johannes" <johannes.berg@...el.com>
Cc:	"David S. Miller" <davem@...emloft.net>,
	Patrick McHardy <kaber@...sh.net>,
	Pablo Neira Ayuso <pablo@...filter.org>,
	Gao feng <gaofeng@...fujitsu.com>,
	"netdev@...r.kernel.org" <netdev@...r.kernel.org>,
	"linux-kernel@...r.kernel.org" <linux-kernel@...r.kernel.org>
Subject: Re: [PATCH next] netlink: prevent deadlock in ctrl_dumpfamily()

On (08/20/13 14:03), Berg, Johannes wrote:
> > +	if (need_locking) {
> > +		/* genl_mutex could be already locked in genl_rcv_msg() */
> > +		rt = genl_family_find_byid(cb->nlh->nlmsg_type);
> > +		need_locking = need_locking && rt->parallel_ops;
> > +	}
> 
> This is equivalent to reverting the patch because parallel_ops will be false for the genl family. :-)
>

sorry, didn't notice that there is already a thread on lkml regarding
this issue. will follow that discussion. the reason was that I see an
actual deadlock on my machine during certain network activities, but
lockdep is silent.

thanks,
	-ss

> johannes
> -- 
> 
> Intel GmbH
> Dornacher Strasse 1
> 85622 Feldkirchen/Muenchen, Deutschland
> Sitz der Gesellschaft: Feldkirchen bei Muenchen
> Geschaeftsfuehrer: Christian Lamprechter, Hannes Schwaderer, Douglas Lusk
> Registergericht: Muenchen HRB 47456
> Ust.-IdNr./VAT Registration No.: DE129385895
> Citibank Frankfurt a.M. (BLZ 502 109 00) 600119052
> 
--
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/