From cda7f6e2cb32f594f35afd34a7cadc186896c6fc Mon Sep 17 00:00:00 2001 From: Rachita Kothiyal Date: Mon, 31 Mar 2008 15:46:51 -0400 Subject: [PATCH] Unionfs: ensure consistent lower inodes types 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 | 18 ++++++++++++++---- 1 file changed, 14 insertions(+), 4 deletions(-) diff --git a/fs/unionfs/lookup.c b/fs/unionfs/lookup.c index b5a390f8c5..17e4f71603 100644 --- a/fs/unionfs/lookup.c +++ b/fs/unionfs/lookup.c @@ -187,6 +187,20 @@ 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 ((lookupmode != INTERPOSE_PARTIAL) && + !S_ISDIR(lower_dentry->d_inode->i_mode) && dentry_count) { + dput(lower_dentry); + continue; + } + /* number of positive dentries */ dentry_count++; @@ -213,10 +227,6 @@ struct dentry *unionfs_lookup_backend(struct dentry *dentry, continue; if (dentry_count == 1) goto out_positive; - /* This can only happen with mixed D-*-F-* */ - BUG_ON(!S_ISDIR(unionfs_lower_dentry(dentry)-> - d_inode->i_mode)); - continue; } } -- 2.34.1