Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1763759AbYBOWll (ORCPT ); Fri, 15 Feb 2008 17:41:41 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1763914AbYBOWhm (ORCPT ); Fri, 15 Feb 2008 17:37:42 -0500 Received: from e6.ny.us.ibm.com ([32.97.182.146]:48733 "EHLO e6.ny.us.ibm.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1762534AbYBOWhi (ORCPT ); Fri, 15 Feb 2008 17:37:38 -0500 Subject: [PATCH 03/30] check for null vfsmount in dentry_open() To: linux-kernel@vger.kernel.org Cc: hch@lst.de, miklos@szeredi.hu, akpm@osdl.org, Dave Hansen From: Dave Hansen Date: Fri, 15 Feb 2008 14:37:24 -0800 References: <20080215223721.9E0A088A@kernel> In-Reply-To: <20080215223721.9E0A088A@kernel> Message-Id: <20080215223724.D5C70940@kernel> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1482 Lines: 42 Make sure no-one calls dentry_open with a NULL vfsmount argument and crap out with a stacktrace otherwise. A NULL file->f_vfsmnt has always been problematic, but with the per-mount r/o tracking we can't accept anymore at all. Acked-by: Al Viro Signed-off-by: Christoph Hellwig Signed-off-by: Dave Hansen --- linux-2.6.git-dave/fs/open.c | 12 ++++++++++++ 1 file changed, 12 insertions(+) diff -puN fs/open.c~check-for-NULL-vfsmount-in-dentry-open fs/open.c --- linux-2.6.git/fs/open.c~check-for-NULL-vfsmount-in-dentry-open 2008-02-15 13:25:42.000000000 -0800 +++ linux-2.6.git-dave/fs/open.c 2008-02-15 13:25:42.000000000 -0800 @@ -903,6 +903,18 @@ struct file *dentry_open(struct dentry * int error; struct file *f; + /* + * We must always pass in a valid mount pointer. Historically + * callers got away with not passing it, but we must enforce this at + * the earliest possible point now to avoid strange problems deep in the + * filesystem stack. + */ + if (!mnt) { + printk(KERN_WARNING "%s called with NULL vfsmount\n", __func__); + dump_stack(); + return ERR_PTR(-EINVAL); + } + error = -ENFILE; f = get_empty_filp(); if (f == NULL) { _ -- 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/