From 3a39a12ad364a9acd1038ba8da67cd8430f30de4 Mon Sep 17 00:00:00 2001 From: Liubin Shu Date: Thu, 4 Apr 2019 16:46:42 +0800 Subject: [PATCH] net: hns: fix KASAN: use-after-free in hns_nic_net_xmit_hw() This patch is trying to fix the issue due to: [27237.844750] BUG: KASAN: use-after-free in hns_nic_net_xmit_hw+0x708/0xa18[hns_enet_drv] After hnae_queue_xmit() in hns_nic_net_xmit_hw(), can be interrupted by interruptions, and than call hns_nic_tx_poll_one() to handle the new packets, and free the skb. So, when turn back to hns_nic_net_xmit_hw(), calling skb->len will cause use-after-free. This patch update tx ring statistics in hns_nic_tx_poll_one() to fix the bug. Signed-off-by: Liubin Shu Signed-off-by: Zhen Lei Signed-off-by: Yonglong Liu Signed-off-by: Peng Li Signed-off-by: David S. Miller --- drivers/net/ethernet/hisilicon/hns/hns_enet.c | 5 +++-- 1 file changed, 3 insertions(+), 2 deletions(-) diff --git a/drivers/net/ethernet/hisilicon/hns/hns_enet.c b/drivers/net/ethernet/hisilicon/hns/hns_enet.c index 60e7d7ae3787..e5a7c0761dbd 100644 --- a/drivers/net/ethernet/hisilicon/hns/hns_enet.c +++ b/drivers/net/ethernet/hisilicon/hns/hns_enet.c @@ -376,8 +376,6 @@ netdev_tx_t hns_nic_net_xmit_hw(struct net_device *ndev, wmb(); /* commit all data before submit */ assert(skb->queue_mapping < priv->ae_handle->q_num); hnae_queue_xmit(priv->ae_handle->qs[skb->queue_mapping], buf_num); - ring->stats.tx_pkts++; - ring->stats.tx_bytes += skb->len; return NETDEV_TX_OK; @@ -999,6 +997,9 @@ static int hns_nic_tx_poll_one(struct hns_nic_ring_data *ring_data, /* issue prefetch for next Tx descriptor */ prefetch(&ring->desc_cb[ring->next_to_clean]); } + /* update tx ring statistics. */ + ring->stats.tx_pkts += pkts; + ring->stats.tx_bytes += bytes; NETIF_TX_UNLOCK(ring); -- 2.30.2