Unionfs: ensure we have lower dentries in d_iput

Signed-off-by: Erez Zadok <ezk@cs.sunysb.edu>

diff --git a/fs/unionfs/dentry.c b/fs/unionfs/dentry.c
index 6b52c91f0dae6d852a29a1ff58de03b5086857b7..01aa2c0971006404d9d4285af71345c62258c213 100644 (file)
--- a/fs/unionfs/dentry.c
+++ b/fs/unionfs/dentry.c
@@ -498,9 +498,10 @@ static void unionfs_d_iput(struct dentry *dentry, struct inode *inode)
 {
        int bindex, rc;
 
+       BUG_ON(!dentry);
        unionfs_read_lock(dentry->d_sb, UNIONFS_SMUTEX_CHILD);
 
-       if (dbstart(dentry) < 0)
+       if (!UNIONFS_D(dentry) || dbstart(dentry) < 0)
                goto drop_lower_inodes;
        for (bindex = dbstart(dentry); bindex <= dbend(dentry); bindex++) {
                if (unionfs_lower_mnt_idx(dentry, bindex)) {