diff --git a/net/netlink/af_netlink.c b/net/netlink/af_netlink.c index 9a0ae7172f92..d8e2e3918ce2 100644 --- a/net/netlink/af_netlink.c +++ b/net/netlink/af_netlink.c @@ -357,25 +357,52 @@ err1: return NULL; } + +static void +__netlink_set_ring(struct sock *sk, struct nl_mmap_req *req, bool tx_ring, void **pg_vec, + unsigned int order) +{ + struct netlink_sock *nlk = nlk_sk(sk); + struct sk_buff_head *queue; + struct netlink_ring *ring; + + queue = tx_ring ? &sk->sk_write_queue : &sk->sk_receive_queue; + ring = tx_ring ? &nlk->tx_ring : &nlk->rx_ring; + + spin_lock_bh(&queue->lock); + + ring->frame_max = req->nm_frame_nr - 1; + ring->head = 0; + ring->frame_size = req->nm_frame_size; + ring->pg_vec_pages = req->nm_block_size / PAGE_SIZE; + + swap(ring->pg_vec_len, req->nm_block_nr); + swap(ring->pg_vec_order, order); + swap(ring->pg_vec, pg_vec); + + __skb_queue_purge(queue); + spin_unlock_bh(&queue->lock); + + WARN_ON(atomic_read(&nlk->mapped)); + + if (pg_vec) + free_pg_vec(pg_vec, order, req->nm_block_nr); +} + static int netlink_set_ring(struct sock *sk, struct nl_mmap_req *req, - bool closing, bool tx_ring) + bool tx_ring) { struct netlink_sock *nlk = nlk_sk(sk); struct netlink_ring *ring; - struct sk_buff_head *queue; void **pg_vec = NULL; unsigned int order = 0; - int err; ring = tx_ring ? &nlk->tx_ring : &nlk->rx_ring; - queue = tx_ring ? &sk->sk_write_queue : &sk->sk_receive_queue; - if (!closing) { - if (atomic_read(&nlk->mapped)) - return -EBUSY; - if (atomic_read(&ring->pending)) - return -EBUSY; - } + if (atomic_read(&nlk->mapped)) + return -EBUSY; + if (atomic_read(&ring->pending)) + return -EBUSY; if (req->nm_block_nr) { if (ring->pg_vec != NULL) @@ -407,31 +434,19 @@ static int netlink_set_ring(struct sock *sk, struct nl_mmap_req *req, return -EINVAL; } - err = -EBUSY; mutex_lock(&nlk->pg_vec_lock); - if (closing || atomic_read(&nlk->mapped) == 0) { - err = 0; - spin_lock_bh(&queue->lock); - - ring->frame_max = req->nm_frame_nr - 1; - ring->head = 0; - ring->frame_size = req->nm_frame_size; - ring->pg_vec_pages = req->nm_block_size / PAGE_SIZE; - - swap(ring->pg_vec_len, req->nm_block_nr); - swap(ring->pg_vec_order, order); - swap(ring->pg_vec, pg_vec); - - __skb_queue_purge(queue); - spin_unlock_bh(&queue->lock); - - WARN_ON(atomic_read(&nlk->mapped)); + if (atomic_read(&nlk->mapped) == 0) { + __netlink_set_ring(sk, req, tx_ring, pg_vec, order); + mutex_unlock(&nlk->pg_vec_lock); + return 0; } + mutex_unlock(&nlk->pg_vec_lock); if (pg_vec) free_pg_vec(pg_vec, order, req->nm_block_nr); - return err; + + return -EBUSY; } static void netlink_mm_open(struct vm_area_struct *vma) @@ -900,10 +915,10 @@ static void netlink_sock_destruct(struct sock *sk) memset(&req, 0, sizeof(req)); if (nlk->rx_ring.pg_vec) - netlink_set_ring(sk, &req, true, false); + __netlink_set_ring(sk, &req, false, NULL, 0); memset(&req, 0, sizeof(req)); if (nlk->tx_ring.pg_vec) - netlink_set_ring(sk, &req, true, true); + __netlink_set_ring(sk, &req, true, NULL, 0); } #endif /* CONFIG_NETLINK_MMAP */ @@ -2223,7 +2238,7 @@ static int netlink_setsockopt(struct socket *sock, int level, int optname, return -EINVAL; if (copy_from_user(&req, optval, sizeof(req))) return -EFAULT; - err = netlink_set_ring(sk, &req, false, + err = netlink_set_ring(sk, &req, optname == NETLINK_TX_RING); break; }