Return-Path: Received: from mx2.netapp.com ([216.240.18.37]:47613 "EHLO mx2.netapp.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751289Ab0LGWis convert rfc822-to-8bit (ORCPT ); Tue, 7 Dec 2010 17:38:48 -0500 Subject: Re: [PATCH] NFS: Fix fcntl F_GETLK not reporting some conflicts From: Trond Myklebust To: Sergey Vlasov Cc: linux-nfs@vger.kernel.org, linux-kernel@vger.kernel.org, Alexander Morozov , stable@kernel.org In-Reply-To: <1290978245-14415-1-git-send-email-vsu@altlinux.ru> References: <1290978245-14415-1-git-send-email-vsu@altlinux.ru> Content-Type: text/plain; charset="UTF-8" Date: Tue, 07 Dec 2010 17:38:46 -0500 Message-ID: <1291761526.3049.48.camel@heimdal.trondhjem.org> Sender: linux-nfs-owner@vger.kernel.org List-ID: MIME-Version: 1.0 On Mon, 2010-11-29 at 00:04 +0300, Sergey Vlasov wrote: > The commit 129a84de2347002f09721cda3155ccfd19fade40 (locks: fix F_GETLK > regression (failure to find conflicts)) fixed the posix_test_lock() > function by itself, however, its usage in NFS changed by the commit > 9d6a8c5c213e34c475e72b245a8eb709258e968c (locks: give posix_test_lock > same interface as ->lock) remained broken - subsequent NFS-specific > locking code received F_UNLCK instead of the user-specified lock type. > To fix the problem, fl->fl_type needs to be saved before the > posix_test_lock() call and restored if no local conflicts were reported. > > Reference: https://bugzilla.kernel.org/show_bug.cgi?id=23892 > Tested-by: Alexander Morozov > Signed-off-by: Sergey Vlasov > Cc: > --- > fs/nfs/file.c | 2 ++ > 1 files changed, 2 insertions(+), 0 deletions(-) > > There seems to be a similar bug in fs/9p/vfs_file.c:v9fs_file_getlock() > and an even worse confusion in fs/afs/flock.c:afs_do_getlk(), but I > can't test them. > > diff --git a/fs/nfs/file.c b/fs/nfs/file.c > index 60677f9..7bf029e 100644 > --- a/fs/nfs/file.c > +++ b/fs/nfs/file.c > @@ -693,6 +693,7 @@ do_getlk(struct file *filp, int cmd, struct file_lock *fl, int is_local) > { > struct inode *inode = filp->f_mapping->host; > int status = 0; > + unsigned int saved_type = fl->fl_type; > > /* Try local locking first */ > posix_test_lock(filp, fl); > @@ -700,6 +701,7 @@ do_getlk(struct file *filp, int cmd, struct file_lock *fl, int is_local) > /* found a conflict */ > goto out; > } > + fl->fl_type = saved_type; > > if (nfs_have_delegation(inode, FMODE_READ)) > goto out_noconflict; Thanks! Applied... -- Trond Myklebust Linux NFS client maintainer NetApp Trond.Myklebust@netapp.com www.netapp.com