Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751351Ab3IPTDa (ORCPT ); Mon, 16 Sep 2013 15:03:30 -0400 Received: from mail-la0-f50.google.com ([209.85.215.50]:36977 "EHLO mail-la0-f50.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751136Ab3IPTD1 (ORCPT ); Mon, 16 Sep 2013 15:03:27 -0400 MIME-Version: 1.0 X-Originating-IP: [86.59.245.170] In-Reply-To: <20130916181938.GD13318@ZenIV.linux.org.uk> References: <1379335925-30858-1-git-send-email-miklos@szeredi.hu> <1379335925-30858-3-git-send-email-miklos@szeredi.hu> <20130916181938.GD13318@ZenIV.linux.org.uk> Date: Mon, 16 Sep 2013 21:03:25 +0200 Message-ID: Subject: Re: [PATCH 02/11] 9p: fix dentry leak in v9fs_vfs_atomic_open_dotl() From: Miklos Szeredi To: Al Viro Cc: Linux-Fsdevel , Kernel Mailing List , "mszeredi@suse.cz" , Eric Van Hensbergen , "M. Mohan Kumar" , stable@vger.kernel.org Content-Type: text/plain; charset=UTF-8 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1810 Lines: 47 On Mon, Sep 16, 2013 at 8:19 PM, Al Viro wrote: > On Mon, Sep 16, 2013 at 02:51:56PM +0200, Miklos Szeredi wrote: >> From: Miklos Szeredi >> >> commit b6f4bee02f "fs/9p: Fix atomic_open" fixed the O_EXCL behavior, but >> results in a dentry leak if v9fs_vfs_lookup() returns non-NULL. > > Frankly, I would prefer to deal with that in fs/namei.c:atomic_open() > instead. I.e. let it call finish_no_open() as it used to do and > turn > if (create_error && dentry->d_inode == NULL) { > error = create_error; > goto out; > } > in fs/namei.c:atomic_open() into > if (!dentry->d_inode) { > if (create_error) { > error = create_error; > goto out; > } > } else if ((open_flag & (O_CREAT | O_EXCL)) == (O_CREAT | O_EXCL)) { > error = -EEXIST; > goto out; > } > > rather than try to deal with that crap in each instance of ->atomic_open()... > Objections? ->atomic_open() could be any one of lookup lookup+create lookup+create+open If it's the second one then the above is wrong. Sure, we could check FILE_CREATED as well, and if file wasn't created yet dentry is positive then we return EEXIST. But for that to be correct we need the last patch in the series, preventing FILE_CREATED from being set unconditionally. Thanks, Miklos -- 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/