From: Trond Myklebust Subject: Re: [PATCH] sunrpc: fix error path - actually return ERR_PTR() on error Date: Fri, 12 Mar 2010 10:09:51 -0500 Message-ID: <1268406591.3156.18.camel@localhost.localdomain> References: <1268401704-9034-1-git-send-email-ext-jani.1.nikula@nokia.com> <201003122314.IAD17160.OtJLHVMFOOSFFQ@I-love.SAKURA.ne.jp> Mime-Version: 1.0 Content-Type: text/plain; charset="UTF-8" Cc: ext-jani.1.nikula@nokia.com, bfields@fieldses.org, neilb@suse.de, davem@davemloft.net, batsakis@netapp.com, bhalevy@panasas.com, linux-nfs@vger.kernel.org, netdev@vger.kernel.org, akpm@linux-foundation.org To: Tetsuo Handa Return-path: Received: from mx2.netapp.com ([216.240.18.37]:17635 "EHLO mx2.netapp.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S934020Ab0CLPKe convert rfc822-to-8bit (ORCPT ); Fri, 12 Mar 2010 10:10:34 -0500 In-Reply-To: <201003122314.IAD17160.OtJLHVMFOOSFFQ@I-love.SAKURA.ne.jp> Sender: linux-nfs-owner@vger.kernel.org List-ID: On Fri, 2010-03-12 at 23:14 +0900, Tetsuo Handa wrote: > Jani Nikula wrote: > > Signed-off-by: Jani Nikula > > > > --- > > > > NOTE: I'm afraid I'm unable to test this; please consider this more a > > bug report than a complete patch. > > --- > Indeed, it has to be "return ERR_PTR(-EINVAL);". > Otherwise, it will trigger NULL pointer dereference some lines later. > > bc_sock = container_of(args->bc_xprt, struct svc_sock, sk_xprt); > bc_sock->sk_bc_xprt = xprt; > > This bug was introduced by f300baba5a1536070d6d77bf0c8c4ca999bb4f0f > "nfsd41: sunrpc: add new xprt class for nfsv4.1 backchannel" and > exists in 2.6.32 and later. Or it should just be dropped. I don't see any reason why nfsd should be trying to set up a callback channel if it doesn't already know that it has a socket. Returning an error value in that case would just be papering over a design bug. Trond