The segfault was observed because there is no NULL check in inode.c in the following function:

__dentry_search_arbit (inode_t *inode)
{
        dentry_t *dentry = NULL;
        dentry_t *trav = NULL;

        list_for_each_entry (trav, &inode->dentry_list, inode_list) {
                if (__is_dentry_hashed (trav)) {
                        dentry = trav;
                        break;
                }
        }

        if (!dentry) {
                list_for_each_entry (trav, &inode->dentry_list, inode_list) {
                        dentry = trav;
                        break;
                }
        }

        return dentry;
}