ecryptfs: don't ignore return value from lock_rename

Signed-off-by: Erez Zadok <ezk@cs.sunysb.edu>
Cc: Dustin Kirkland <kirkland@canonical.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Tyler Hicks <tyhicks@linux.vnet.ibm.com>

diff --git a/fs/ecryptfs/inode.c b/fs/ecryptfs/inode.c
index 5726d7a..764dc77 100644 (file)
--- a/fs/ecryptfs/inode.c
+++ b/fs/ecryptfs/inode.c
@@ -614,6 +614,7 @@ ecryptfs_rename(struct inode *old_dir, struct dentry *old_dentry,
        struct dentry *lower_new_dentry;
        struct dentry *lower_old_dir_dentry;
        struct dentry *lower_new_dir_dentry;
        struct dentry *lower_new_dentry;
        struct dentry *lower_old_dir_dentry;
        struct dentry *lower_new_dir_dentry;

+       struct dentry *trap = NULL;

 
        lower_old_dentry = ecryptfs_dentry_to_lower(old_dentry);
        lower_new_dentry = ecryptfs_dentry_to_lower(new_dentry);
 
        lower_old_dentry = ecryptfs_dentry_to_lower(old_dentry);
        lower_new_dentry = ecryptfs_dentry_to_lower(new_dentry);


@@ -621,7 +622,17 @@ ecryptfs_rename(struct inode *old_dir, struct dentry *old_dentry,
        dget(lower_new_dentry);
        lower_old_dir_dentry = dget_parent(lower_old_dentry);
        lower_new_dir_dentry = dget_parent(lower_new_dentry);
        dget(lower_new_dentry);
        lower_old_dir_dentry = dget_parent(lower_old_dentry);
        lower_new_dir_dentry = dget_parent(lower_new_dentry);

-       lock_rename(lower_old_dir_dentry, lower_new_dir_dentry);
+       trap = lock_rename(lower_old_dir_dentry, lower_new_dir_dentry);
+       /* source should not be ancestor of target */
+       if (trap == lower_old_dentry) {
+               rc = -EINVAL;
+               goto out_lock;
+       }
+       /* target should not be ancestor of source */
+       if (trap == lower_new_dentry) {
+               rc = -ENOTEMPTY;
+               goto out_lock;
+       }

        rc = vfs_rename(lower_old_dir_dentry->d_inode, lower_old_dentry,
                        lower_new_dir_dentry->d_inode, lower_new_dentry);
        if (rc)
        rc = vfs_rename(lower_old_dir_dentry->d_inode, lower_old_dentry,
                        lower_new_dir_dentry->d_inode, lower_new_dentry);
        if (rc)