diff --git a/net/xdp/xsk.c b/net/xdp/xsk.c index d6b500dc4208..426e287431d2 100644 --- a/net/xdp/xsk.c +++ b/net/xdp/xsk.c @@ -418,18 +418,8 @@ EXPORT_SYMBOL(xsk_tx_peek_release_desc_batch); static int xsk_wakeup(struct xdp_sock *xs, u8 flags) { struct net_device *dev = xs->dev; - int err; - rcu_read_lock(); - err = dev->netdev_ops->ndo_xsk_wakeup(dev, xs->queue_id, flags); - rcu_read_unlock(); - - return err; -} - -static int xsk_zc_xmit(struct xdp_sock *xs) -{ - return xsk_wakeup(xs, XDP_WAKEUP_TX); + return dev->netdev_ops->ndo_xsk_wakeup(dev, xs->queue_id, flags); } static void xsk_destruct_skb(struct sk_buff *skb) @@ -548,6 +538,12 @@ static int xsk_generic_xmit(struct sock *sk) mutex_lock(&xs->mutex); + /* Since we dropped the RCU read lock, the socket state might have changed. */ + if (unlikely(!xsk_is_bound(xs))) { + err = -ENXIO; + goto out; + } + if (xs->queue_id >= xs->dev->real_num_tx_queues) goto out; @@ -611,16 +607,26 @@ out: return err; } -static int __xsk_sendmsg(struct sock *sk) +static int xsk_xmit(struct sock *sk) { struct xdp_sock *xs = xdp_sk(sk); + int ret; if (unlikely(!(xs->dev->flags & IFF_UP))) return -ENETDOWN; if (unlikely(!xs->tx)) return -ENOBUFS; - return xs->zc ? xsk_zc_xmit(xs) : xsk_generic_xmit(sk); + if (xs->zc) + return xsk_wakeup(xs, XDP_WAKEUP_TX); + + /* Drop the RCU lock since the SKB path might sleep. */ + rcu_read_unlock(); + ret = xsk_generic_xmit(sk); + /* Reaquire RCU lock before going into common code. */ + rcu_read_lock(); + + return ret; } static bool xsk_no_wakeup(struct sock *sk) @@ -634,7 +640,7 @@ static bool xsk_no_wakeup(struct sock *sk) #endif } -static int xsk_sendmsg(struct socket *sock, struct msghdr *m, size_t total_len) +static int __xsk_sendmsg(struct socket *sock, struct msghdr *m, size_t total_len) { bool need_wait = !(m->msg_flags & MSG_DONTWAIT); struct sock *sk = sock->sk; @@ -654,11 +660,22 @@ static int xsk_sendmsg(struct socket *sock, struct msghdr *m, size_t total_len) pool = xs->pool; if (pool->cached_need_wakeup & XDP_WAKEUP_TX) - return __xsk_sendmsg(sk); + return xsk_xmit(sk); return 0; } -static int xsk_recvmsg(struct socket *sock, struct msghdr *m, size_t len, int flags) +static int xsk_sendmsg(struct socket *sock, struct msghdr *m, size_t total_len) +{ + int ret; + + rcu_read_lock(); + ret = __xsk_sendmsg(sock, m, total_len); + rcu_read_unlock(); + + return ret; +} + +static int __xsk_recvmsg(struct socket *sock, struct msghdr *m, size_t len, int flags) { bool need_wait = !(flags & MSG_DONTWAIT); struct sock *sk = sock->sk; @@ -684,6 +701,17 @@ static int xsk_recvmsg(struct socket *sock, struct msghdr *m, size_t len, int fl return 0; } +static int xsk_recvmsg(struct socket *sock, struct msghdr *m, size_t len, int flags) +{ + int ret; + + rcu_read_lock(); + ret = __xsk_recvmsg(sock, m, len, flags); + rcu_read_unlock(); + + return ret; +} + static __poll_t xsk_poll(struct file *file, struct socket *sock, struct poll_table_struct *wait) { @@ -694,8 +722,11 @@ static __poll_t xsk_poll(struct file *file, struct socket *sock, sock_poll_wait(file, sock, wait); - if (unlikely(!xsk_is_bound(xs))) + rcu_read_lock(); + if (unlikely(!xsk_is_bound(xs))) { + rcu_read_unlock(); return mask; + } pool = xs->pool; @@ -704,7 +735,7 @@ static __poll_t xsk_poll(struct file *file, struct socket *sock, xsk_wakeup(xs, pool->cached_need_wakeup); else /* Poll needs to drive Tx also in copy mode */ - __xsk_sendmsg(sk); + xsk_xmit(sk); } if (xs->rx && !xskq_prod_is_empty(xs->rx)) @@ -712,6 +743,7 @@ static __poll_t xsk_poll(struct file *file, struct socket *sock, if (xs->tx && xsk_tx_writeable(xs)) mask |= EPOLLOUT | EPOLLWRNORM; + rcu_read_unlock(); return mask; } @@ -743,7 +775,6 @@ static void xsk_unbind_dev(struct xdp_sock *xs) /* Wait for driver to stop using the xdp socket. */ xp_del_xsk(xs->pool, xs); - xs->dev = NULL; synchronize_net(); dev_put(dev); }