On Mon, Apr 04, 2022 at 03:27:26PM +0300, Leon Romanovsky wrote:
> +static int compare_netdev_and_ip(int ifindex_a, struct sockaddr *sa,
> + int ifindex_b, struct sockaddr *sb)
> +{
> + if (ifindex_a != ifindex_b)
> + return ifindex_a - ifindex_b;
These subtraction tricks don't work if the value can overflow
INT_MAX - INT_MIN == undefined
> +static int cma_add_id_to_tree(struct rdma_id_private *node_id_priv)
> +{
> + struct rb_node **new = &id_table.rb_node, *parent = NULL;
This read of rb_node has to be under the spinlock
> + struct id_table_entry *this, *node;
> + struct rdma_id_private *id_priv;
> + unsigned long flags;
> + int result;
> +
> + node = kzalloc(sizeof(*node), GFP_KERNEL);
> + if (!node)
> + return -ENOMEM;
> +
> + spin_lock_irqsave(&id_table_lock, flags);
> + while (*new) {
> + this = container_of(*new, struct id_table_entry, rb_node);
Because rebalacing can alter the head
> + id_priv = list_first_entry(
> + &this->id_list, struct rdma_id_private, id_list_entry);
> + result = compare_netdev_and_ip(
> + node_id_priv->id.route.addr.dev_addr.bound_dev_if,
> + cma_dst_addr(node_id_priv),
> + id_priv->id.route.addr.dev_addr.bound_dev_if,
> + cma_dst_addr(id_priv));
This pattern keeps repeating, one of the arguments to compare should
just be the id_table_entry * and do the list_first/etc inside the
compare.
Jason
