Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753367AbcKGNHR (ORCPT ); Mon, 7 Nov 2016 08:07:17 -0500 Received: from mx2.suse.de ([195.135.220.15]:36981 "EHLO mx2.suse.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752381AbcKGNFw (ORCPT ); Mon, 7 Nov 2016 08:05:52 -0500 X-Amavis-Alert: BAD HEADER SECTION, Duplicate header field: "References" From: Jiri Slaby To: stable@vger.kernel.org Cc: linux-kernel@vger.kernel.org, Jan Kara , Jiri Slaby Subject: [PATCH 3.12 53/72] isofs: Do not return EACCES for unknown filesystems Date: Mon, 7 Nov 2016 14:05:00 +0100 Message-Id: <34b5763de87a486b6f1fa430ee938695b0312be8.1478523828.git.jslaby@suse.cz> X-Mailer: git-send-email 2.10.2 In-Reply-To: <0f3caac741164dcff670ae0f4d1cfcb0a7026a1c.1478523828.git.jslaby@suse.cz> References: <0f3caac741164dcff670ae0f4d1cfcb0a7026a1c.1478523828.git.jslaby@suse.cz> In-Reply-To: References: Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1746 Lines: 53 From: Jan Kara 3.12-stable review patch. If anyone has any objections, please let me know. =============== commit a2ed0b391dd9c3ef1d64c7c3e370f4a5ffcd324a upstream. When isofs_mount() is called to mount a device read-write, it returns EACCES even before it checks that the device actually contains an isofs filesystem. This may confuse mount(8) which then tries to mount all subsequent filesystem types in read-only mode. Fix the problem by returning EACCES only once we verify that the device indeed contains an iso9660 filesystem. Fixes: 17b7f7cf58926844e1dd40f5eb5348d481deca6a Reported-by: Kent Overstreet Reported-by: Karel Zak Signed-off-by: Jan Kara Signed-off-by: Jiri Slaby --- fs/isofs/inode.c | 8 +++++--- 1 file changed, 5 insertions(+), 3 deletions(-) diff --git a/fs/isofs/inode.c b/fs/isofs/inode.c index 2e2af97df075..77ac62441385 100644 --- a/fs/isofs/inode.c +++ b/fs/isofs/inode.c @@ -710,6 +710,11 @@ static int isofs_fill_super(struct super_block *s, void *data, int silent) pri_bh = NULL; root_found: + /* We don't support read-write mounts */ + if (!(s->s_flags & MS_RDONLY)) { + error = -EACCES; + goto out_freebh; + } if (joliet_level && (pri == NULL || !opt.rock)) { /* This is the case of Joliet with the norock mount flag. @@ -1522,9 +1527,6 @@ struct inode *__isofs_iget(struct super_block *sb, static struct dentry *isofs_mount(struct file_system_type *fs_type, int flags, const char *dev_name, void *data) { - /* We don't support read-write mounts */ - if (!(flags & MS_RDONLY)) - return ERR_PTR(-EACCES); return mount_bdev(fs_type, flags, dev_name, data, isofs_fill_super); } -- 2.10.2