diff --git a/net/xdp/xsk.c b/net/xdp/xsk.c index 8c9056f06989..c2f1af3b6a7c 100644 --- a/net/xdp/xsk.c +++ b/net/xdp/xsk.c @@ -186,10 +186,23 @@ static int __xsk_rcv_zc(struct xdp_sock *xs, struct xdp_buff *xdp, u32 len) return err; } +static bool xsk_is_bound(struct xdp_sock *xs) +{ + if (READ_ONCE(xs->state) == XSK_BOUND) { + /* Matches smp_wmb() in bind(). */ + smp_rmb(); + return true; + } + return false; +} + int xsk_rcv(struct xdp_sock *xs, struct xdp_buff *xdp) { u32 len; + if (!xsk_is_bound(xs)) + return -EINVAL; + if (xs->dev != xdp->rxq->dev || xs->queue_id != xdp->rxq->queue_index) return -EINVAL; @@ -387,7 +400,7 @@ static int xsk_sendmsg(struct socket *sock, struct msghdr *m, size_t total_len) struct sock *sk = sock->sk; struct xdp_sock *xs = xdp_sk(sk); - if (unlikely(!xs->dev)) + if (unlikely(!xsk_is_bound(xs))) return -ENXIO; if (unlikely(!(xs->dev->flags & IFF_UP))) return -ENETDOWN; @@ -403,10 +416,15 @@ static unsigned int xsk_poll(struct file *file, struct socket *sock, struct poll_table_struct *wait) { unsigned int mask = datagram_poll(file, sock, wait); - struct sock *sk = sock->sk; - struct xdp_sock *xs = xdp_sk(sk); - struct net_device *dev = xs->dev; - struct xdp_umem *umem = xs->umem; + struct xdp_sock *xs = xdp_sk(sock->sk); + struct net_device *dev; + struct xdp_umem *umem; + + if (unlikely(!xsk_is_bound(xs))) + return mask; + + dev = xs->dev; + umem = xs->umem; if (umem->need_wakeup) dev->netdev_ops->ndo_xsk_wakeup(dev, xs->queue_id, @@ -442,10 +460,9 @@ static void xsk_unbind_dev(struct xdp_sock *xs) { struct net_device *dev = xs->dev; - if (!dev || xs->state != XSK_BOUND) + if (xs->state != XSK_BOUND) return; - - xs->state = XSK_UNBOUND; + WRITE_ONCE(xs->state, XSK_UNBOUND); /* Wait for driver to stop using the xdp socket. */ xdp_del_sk_umem(xs->umem, xs); @@ -520,7 +537,9 @@ static int xsk_release(struct socket *sock) local_bh_enable(); xsk_delete_from_maps(xs); + mutex_lock(&xs->mutex); xsk_unbind_dev(xs); + mutex_unlock(&xs->mutex); xskq_destroy(xs->rx); xskq_destroy(xs->tx); @@ -632,12 +651,12 @@ static int xsk_bind(struct socket *sock, struct sockaddr *addr, int addr_len) } umem_xs = xdp_sk(sock->sk); - if (!umem_xs->umem) { - /* No umem to inherit. */ + if (!xsk_is_bound(umem_xs)) { err = -EBADF; sockfd_put(sock); goto out_unlock; - } else if (umem_xs->dev != dev || umem_xs->queue_id != qid) { + } + if (umem_xs->dev != dev || umem_xs->queue_id != qid) { err = -EINVAL; sockfd_put(sock); goto out_unlock; @@ -671,10 +690,15 @@ static int xsk_bind(struct socket *sock, struct sockaddr *addr, int addr_len) xdp_add_sk_umem(xs->umem, xs); out_unlock: - if (err) + if (err) { dev_put(dev); - else - xs->state = XSK_BOUND; + } else { + /* Matches smp_rmb() in bind() for shared umem + * sockets, and xsk_is_bound(). + */ + smp_wmb(); + WRITE_ONCE(xs->state, XSK_BOUND); + } out_release: mutex_unlock(&xs->mutex); rtnl_unlock(); @@ -927,7 +951,7 @@ static int xsk_mmap(struct file *file, struct socket *sock, unsigned long pfn; struct page *qpg; - if (xs->state != XSK_READY) + if (READ_ONCE(xs->state) != XSK_READY) return -EBUSY; if (offset == XDP_PGOFF_RX_RING) {