Return-Path: linux-nfs-owner@vger.kernel.org Received: from mx11.netapp.com ([216.240.18.76]:10054 "EHLO mx11.netapp.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752466Ab3KLRu0 convert rfc822-to-8bit (ORCPT ); Tue, 12 Nov 2013 12:50:26 -0500 From: "Myklebust, Trond" To: "J. Bruce Fields" CC: Jeff Layton , Weston Andros Adamson , linux-nfs list , "chuck.lever@oracle.com" Subject: Re: Thread overran stack, or stack corrupted BUG on mount Date: Tue, 12 Nov 2013 17:50:22 +0000 Message-ID: <1384278619.4779.31.camel@leira.trondhjem.org> References: <2C73011F-0939-434C-9E4D-13A1EB1403D7@netapp.com> <20131112105539.4f804fc6@tlielax.poochiereds.net> <20131112112021.1a0a60ca@tlielax.poochiereds.net> <20131112165731.GD15060@fieldses.org> In-Reply-To: <20131112165731.GD15060@fieldses.org> Content-Type: text/plain; charset="utf-7" MIME-Version: 1.0 Sender: linux-nfs-owner@vger.kernel.org List-ID: On Tue, 2013-11-12 at 11:57 -0500, J. Bruce Fields wrote: +AD4- On Tue, Nov 12, 2013 at 11:20:21AM -0500, Jeff Layton wrote: +AD4- +AD4- On Tue, 12 Nov 2013 10:55:39 -0500 +AD4- +AD4- Jeff Layton +ADw-jlayton+AEA-redhat.com+AD4- wrote: +AD4- +AD4- +AD4- +AD4- +AD4- On Tue, 12 Nov 2013 15:31:34 +-0000 +AD4- +AD4- +AD4- Weston Andros Adamson +ADw-dros+AEA-netapp.com+AD4- wrote: +AD4- +AD4- +AD4- +AD4- How that ends up smashing the stack, I'm not sure though. +AD4- +AD4- rpc+AF8-free+AF8-client(clnt) +AD4- rpc+AF8-release+AF8-client(clnt-+AD4-cl+AF8-parent) +AD4- rpc+AF8-free+AF8-auth(clnt) +AD4- free+AF8-free+AF8-client(clnt) +AD4- +AD4- So freeing a client with N ancestors can take N times the stack as +AD4- freeing a single client. +AD4- +AD4- (Are there any other cases that can create arbitrarily long cl+AF8-parent +AD4- chains?) Ewww.... At this point, that would be pretty much anything that calls rpc+AF8-clone+AF8-client+AF8-set+AF8-auth() in response to a NFS4ERR+AF8-WRONG+AF8-SEC. -- Trond Myklebust Linux NFS client maintainer NetApp Trond.Myklebust+AEA-netapp.com www.netapp.com