From mboxrd@z Thu Jan 1 00:00:00 1970 From: hujianyang Subject: [PATCH] ovl: Fix opaque regression in ovl_lookup Date: Tue, 6 Jan 2015 16:10:01 +0800 Message-ID: <54AB9859.6070704@huawei.com> Mime-Version: 1.0 Content-Type: text/plain; charset="ISO-8859-1" Content-Transfer-Encoding: 7bit Cc: , "linux-fsdevel@vger.kernel.org" To: Miklos Szeredi Return-path: Received: from szxga03-in.huawei.com ([119.145.14.66]:33841 "EHLO szxga03-in.huawei.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752475AbbAFIKT (ORCPT ); Tue, 6 Jan 2015 03:10:19 -0500 Sender: linux-fsdevel-owner@vger.kernel.org List-ID: Current multi-layer support overlayfs has a regression in .lookup(). If there is a directory in upperdir and a regular file has same name in lowerdir in a merged directory, lower file is hidden and upper directory is set to opaque in former case. But it is changed in present code. In lowerdir lookup path, if a found inode is not directory, the type checking of previous inode is missing. This inode will be copied to the lowerstack of ovl_entry directly. That will lead to several wrong conditions, for example, the reading of the directory in upperdir may return an error like: ls: reading directory .: Not a directory This patch makes the lowerdir lookup path check the opaque for non-directory file too. Signed-off-by: hujianyang --- fs/overlayfs/super.c | 8 +++++--- 1 files changed, 5 insertions(+), 3 deletions(-) diff --git a/fs/overlayfs/super.c b/fs/overlayfs/super.c index d50e3ed..47ab5f4 100644 --- a/fs/overlayfs/super.c +++ b/fs/overlayfs/super.c @@ -400,15 +400,17 @@ struct dentry *ovl_lookup(struct inode *dir, struct dentry *dentry, * * FIXME: check for opaqueness maybe better done in remove code. */ - if (!S_ISDIR(this->d_inode->i_mode)) { + if (!S_ISDIR(this->d_inode->i_mode)) opaque = true; - } else if (prev && (!S_ISDIR(prev->d_inode->i_mode) || - !S_ISDIR(this->d_inode->i_mode))) { + + if (prev && (!S_ISDIR(prev->d_inode->i_mode) || + !S_ISDIR(this->d_inode->i_mode))) { if (prev == upperdentry) upperopaque = true; dput(this); break; } + stack[ctr].dentry = this; stack[ctr].mnt = lowerpath.mnt; ctr++; -- 1.6.0.2