From mboxrd@z Thu Jan 1 00:00:00 1970 From: Erez Zadok Subject: [PATCH 02/17] Unionfs: ensure consistent lower inodes types Date: Sat, 16 Feb 2008 21:57:11 -0500 Message-ID: <1203217047142-git-send-email-ezk@cs.sunysb.edu> References: <12032170461107-git-send-email-ezk@cs.sunysb.edu> Cc: linux-kernel@vger.kernel.org, linux-fsdevel@vger.kernel.org, viro@ftp.linux.org.uk, hch@infradead.org, Erez Zadok , Himanshu Kanda To: akpm@linux-foundation.org Return-path: Received: from filer.fsl.cs.sunysb.edu ([130.245.126.2]:36269 "EHLO filer.fsl.cs.sunysb.edu" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1756801AbYBQC5w (ORCPT ); Sat, 16 Feb 2008 21:57:52 -0500 In-Reply-To: <12032170461107-git-send-email-ezk@cs.sunysb.edu> Sender: linux-fsdevel-owner@vger.kernel.org List-ID: When looking up a lower object in multiple branches, especially for directories, ignore any existing entries whose type is different than the type of the first found object (otherwise we'll be trying to, say, call readdir on a non-dir inode). Signed-off-by: Himanshu Kanda Signed-off-by: Erez Zadok --- fs/unionfs/lookup.c | 13 +++++++++++++ 1 files changed, 13 insertions(+), 0 deletions(-) diff --git a/fs/unionfs/lookup.c b/fs/unionfs/lookup.c index b9ee072..755158e 100644 --- a/fs/unionfs/lookup.c +++ b/fs/unionfs/lookup.c @@ -256,6 +256,19 @@ struct dentry *unionfs_lookup_backend(struct dentry *dentry, continue; } + /* + * If we already found at least one positive dentry + * (dentry_count is non-zero), then we skip all remaining + * positive dentries if their type is a non-dir. This is + * because only directories are allowed to stack on multiple + * branches, but we have to skip non-dirs (to avoid, say, + * calling readdir on a regular file). + */ + if (!S_ISDIR(lower_dentry->d_inode->i_mode) && dentry_count) { + dput(lower_dentry); + continue; + } + /* number of positive dentries */ dentry_count++; -- 1.5.2.2