Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1755852AbZGFFrj (ORCPT ); Mon, 6 Jul 2009 01:47:39 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1753164AbZGFFrb (ORCPT ); Mon, 6 Jul 2009 01:47:31 -0400 Received: from casper.infradead.org ([85.118.1.10]:35317 "EHLO casper.infradead.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752905AbZGFFra (ORCPT ); Mon, 6 Jul 2009 01:47:30 -0400 Date: Sun, 5 Jul 2009 22:48:23 -0700 From: Arjan van de Ven To: Amerigo Wang Cc: linux-kernel@vger.kernel.org, Jeff Mahoney , Yan Zheng , Josef Bacik , Chris Mason , Amerigo Wang , akpm@linux-foundation.org, linux-btrfs@vger.kernel.org, Sven Wegener Subject: Re: [Patch] btrfs: use file_remove_suid() after i_mutex is held Message-ID: <20090705224823.5679075f@infradead.org> In-Reply-To: <20090706053128.6318.16410.sendpatchset@localhost.localdomain> References: <20090706053128.6318.16410.sendpatchset@localhost.localdomain> Organization: Intel X-Mailer: Claws Mail 3.7.1 (GTK+ 2.14.7; i386-redhat-linux-gnu) Mime-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit X-SRS-Rewrite: SMTP reverse-path rewritten from by casper.infradead.org See http://www.infradead.org/rpr.html Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1347 Lines: 48 On Mon, 6 Jul 2009 01:29:14 -0400 Amerigo Wang wrote: > > file_remove_suid() should be called with i_mutex held, > file_update_time() too. So move them after mutex_lock(). > > Plus, check the return value of kmalloc(). > > Signed-off-by: WANG Cong > > --- > diff --git a/fs/btrfs/file.c b/fs/btrfs/file.c > index 7c3cd24..cd36301 100644 > --- a/fs/btrfs/file.c > +++ b/fs/btrfs/file.c > @@ -944,14 +944,17 @@ static ssize_t btrfs_file_write(struct file > *file, const char __user *buf, if (count == 0) > goto out_nolock; > > + mutex_lock(&inode->i_mutex); > + > err = file_remove_suid(file); > if (err) > - goto out_nolock; > + goto out; > file_update_time(file); > > pages = kmalloc(nrptrs * sizeof(struct page *), GFP_KERNEL); > + if (!pages) > + goto out; > Hi, I don't think you can keep this at GFP_KERNEL once you hold i_mutex.... very likely this needs to now turn into GFP_NOFS! -- Arjan van de Ven Intel Open Source Technology Centre For development, discussion and tips for power savings, visit http://www.lesswatts.org -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/