From mboxrd@z Thu Jan 1 00:00:00 1970 From: "J. Bruce Fields" Subject: Re: [PATCHv3] locks: prevent side-effects of locks_release_private before file_lock is initialized Date: Fri, 27 Jul 2012 16:45:52 -0400 Message-ID: <20120727204552.GA6388@fieldses.org> References: <20120707190451.GA17049@fieldses.org> <1343364172-1763-1-git-send-email-filbranden@gmail.com> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Cc: Al Viro , Matthew Wilcox , linux-fsdevel@vger.kernel.org, linux-kernel@vger.kernel.org To: Filipe Brandenburger Return-path: Content-Disposition: inline In-Reply-To: <1343364172-1763-1-git-send-email-filbranden@gmail.com> Sender: linux-kernel-owner@vger.kernel.org List-Id: linux-fsdevel.vger.kernel.org On Fri, Jul 27, 2012 at 12:42:52AM -0400, Filipe Brandenburger wrote: > When calling fcntl(fd, F_SETLEASE, lck) [with lck=F_WRLCK or F_RDLCK], > the custom signal or owner (if any were previously set using F_SETSIG > or F_SETOWN fcntls) would be reset when F_SETLEASE was called for the > second time on the same file descriptor. > > This bug is a regression of 2.6.37 and is described here: > https://bugzilla.kernel.org/show_bug.cgi?id=43336 > > This patch reverts a commit from Oct 2004 (with subject "nfs4 lease: > move the f_delown processing") which originally introduced the > lm_release_private callback. Looks fine, thanks. I think can also do something like the following (on top of your patch). --b. commit 96d6d59ceaeaacba4088862f3c57fcd011f52832 Author: J. Bruce Fields Date: Fri Jul 27 16:18:00 2012 -0400 locks: move lease-specific code out of locks_delete_lock No point putting something only used by one caller into common code. Signed-off-by: J. Bruce Fields diff --git a/fs/locks.c b/fs/locks.c index 86668dd..541075a 100644 --- a/fs/locks.c +++ b/fs/locks.c @@ -570,12 +570,6 @@ static void locks_delete_lock(struct file_lock **thisfl_p) fl->fl_next = NULL; list_del_init(&fl->fl_link); - fasync_helper(0, fl->fl_file, 0, &fl->fl_fasync); - if (fl->fl_fasync != NULL) { - printk(KERN_ERR "locks_delete_lock: fasync == %p\n", fl->fl_fasync); - fl->fl_fasync = NULL; - } - if (fl->fl_nspid) { put_pid(fl->fl_nspid); fl->fl_nspid = NULL; @@ -1150,6 +1144,11 @@ int lease_modify(struct file_lock **before, int arg) f_delown(filp); filp->f_owner.signum = 0; + fasync_helper(0, fl->fl_file, 0, &fl->fl_fasync); + if (fl->fl_fasync != NULL) { + printk(KERN_ERR "locks_delete_lock: fasync == %p\n", fl->fl_fasync); + fl->fl_fasync = NULL; + } locks_delete_lock(before); } return 0;