[PATCH 4.9 28/28] net: hns: Fix a skb used after free bug

Greg Kroah-Hartman
2018-03-29T18:00:47Z

From: Yunsheng Lin <linyunsheng@huawei.com>

commit 27463ad99f738ed93c7c8b3e2e5bc8c4853a2ff2 upstream.

skb maybe freed in hns_nic_net_xmit_hw() and return NETDEV_TX_OK,
which cause hns_nic_net_xmit to use a freed skb.

BUG: KASAN: use-after-free in hns_nic_net_xmit_hw+0x62c/0x940...
[17659.112635] alloc_debug_processing+0x18c/0x1a0
[17659.117208] __slab_alloc+0x52c/0x560
[17659.120909] kmem_cache_alloc_node+0xac/0x2c0
[17659.125309] __alloc_skb+0x6c/0x260
[17659.128837] tcp_send_ack+0x8c/0x280
[17659.132449] __tcp_ack_snd_check+0x9c/0xf0
[17659.136587] tcp_rcv_established+0x5a4/0xa70
[17659.140899] tcp_v4_do_rcv+0x27c/0x620
[17659.144687] tcp_prequeue_process+0x108/0x170
[17659.149085] tcp_recvmsg+0x940/0x1020
[17659.152787] inet_recvmsg+0x124/0x180
[17659.156488] sock_recvmsg+0x64/0x80
[17659.160012] SyS_recvfrom+0xd8/0x180
[17659.163626] __sys_trace_return+0x0/0x4
[17659.167506] INFO: Freed in kfree_skbmem+0xa0/0xb0 age=23 cpu=1 pid=13
[17659.174000] free_debug_processing+0x1d4/0x2c0
[17659.178486] __slab_free+0x240/0x390
[17659.182100] kmem_cache_free+0x24c/0x270
[17659.186062] kfree_skbmem+0xa0/0xb0
[17659.189587] __kfree_skb+0x28/0x40
[17659.193025] napi_gro_receive+0x168/0x1c0
[17659.197074] hns_nic_rx_up_pro+0x58/0x90
[17659.201038] hns_nic_rx_poll_one+0x518/0xbc0
[17659.205352] hns_nic_common_poll+0x94/0x140
[17659.209576] net_rx_action+0x458/0x5e0
[17659.213363] __do_softirq+0x1b8/0x480
[17659.217062] run_ksoftirqd+0x64/0x80
[17659.220679] smpboot_thread_fn+0x224/0x310
[17659.224821] kthread+0x150/0x170
[17659.228084] ret_from_fork+0x10/0x40

BUG: KASAN: use-after-free in hns_nic_net_xmit+0x8c/0xc0...
[17751.080490] __slab_alloc+0x52c/0x560
[17751.084188] kmem_cache_alloc+0x244/0x280
[17751.088238] __build_skb+0x40/0x150
[17751.091764] build_skb+0x28/0x100
[17751.095115] __alloc_rx_skb+0x94/0x150
[17751.098900] __napi_alloc_skb+0x34/0x90
[17751.102776] hns_nic_rx_poll_one+0x180/0xbc0
[17751.107097] hns_nic_common_poll+0x94/0x140
[17751.111333] net_rx_action+0x458/0x5e0
[17751.115123] __do_softirq+0x1b8/0x480
[17751.118823] run_ksoftirqd+0x64/0x80
[17751.122437] smpboot_thread_fn+0x224/0x310
[17751.126575] kthread+0x150/0x170
[17751.129838] ret_from_fork+0x10/0x40
[17751.133454] INFO: Freed in kfree_skbmem+0xa0/0xb0 age=19 cpu=7 pid=43
[17751.139951] free_debug_processing+0x1d4/0x2c0
[17751.144436] __slab_free+0x240/0x390
[17751.148051] kmem_cache_free+0x24c/0x270
[17751.152014] kfree_skbmem+0xa0/0xb0
[17751.155543] __kfree_skb+0x28/0x40
[17751.159022] napi_gro_receive+0x168/0x1c0
[17751.163074] hns_nic_rx_up_pro+0x58/0x90
[17751.167041] hns_nic_rx_poll_one+0x518/0xbc0
[17751.171358] hns_nic_common_poll+0x94/0x140
[17751.175585] net_rx_action+0x458/0x5e0
[17751.179373] __do_softirq+0x1b8/0x480
[17751.183076] run_ksoftirqd+0x64/0x80
[17751.186691] smpboot_thread_fn+0x224/0x310
[17751.190826] kthread+0x150/0x170
[17751.194093] ret_from_fork+0x10/0x40

Fixes: 13ac695e7ea1 ("net:hns: Add support of Hip06 SoC to the Hislicon Network Subsystem")
Signed-off-by: Yunsheng Lin <linyunsheng@huawei.com>
Signed-off-by: lipeng <lipeng321@huawei.com>
Reported-by: Jun He <hjat2005@huawei.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Erick Reyes <erickreyes@google.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

---
drivers/net/ethernet/hisilicon/hns/hns_enet.c | 22 ++++++++++------------
drivers/net/ethernet/hisilicon/hns/hns_enet.h | 6 +++---
2 files changed, 13 insertions(+), 15 deletions(-)

--- a/drivers/net/ethernet/hisilicon/hns/hns_enet.c
+++ b/drivers/net/ethernet/hisilicon/hns/hns_enet.c
@@ -299,9 +299,9 @@ static void fill_tso_desc(struct hnae_ri
mtu);
}

-int hns_nic_net_xmit_hw(struct net_device *ndev,
- struct sk_buff *skb,
- struct hns_nic_ring_data *ring_data)
+netdev_tx_t hns_nic_net_xmit_hw(struct net_device *ndev,
+ struct sk_buff *skb,
+ struct hns_nic_ring_data *ring_data)
{
struct hns_nic_priv *priv = netdev_priv(ndev);
struct hnae_ring *ring = ring_data->ring;
@@ -360,6 +360,10 @@ int hns_nic_net_xmit_hw(struct net_devic
dev_queue = netdev_get_tx_queue(ndev, skb->queue_mapping);
netdev_tx_sent_queue(dev_queue, skb->len);

+ netif_trans_update(ndev);
+ ndev->stats.tx_bytes += skb->len;
+ ndev->stats.tx_packets++;
+
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);
@@ -1408,17 +1412,11 @@ static netdev_tx_t hns_nic_net_xmit(stru
struct net_device *ndev)
{
struct hns_nic_priv *priv = netdev_priv(ndev);
- int ret;

assert(skb->queue_mapping < ndev->ae_handle->q_num);
- ret = hns_nic_net_xmit_hw(ndev, skb,
- &tx_ring_data(priv, skb->queue_mapping));
- if (ret == NETDEV_TX_OK) {
- netif_trans_update(ndev);
- ndev->stats.tx_bytes += skb->len;
- ndev->stats.tx_packets++;
- }
- return (netdev_tx_t)ret;
+
+ return hns_nic_net_xmit_hw(ndev, skb,
+ &tx_ring_data(priv, skb->queue_mapping));
}

static int hns_nic_change_mtu(struct net_device *ndev, int new_mtu)
--- a/drivers/net/ethernet/hisilicon/hns/hns_enet.h
+++ b/drivers/net/ethernet/hisilicon/hns/hns_enet.h
@@ -91,8 +91,8 @@ void hns_ethtool_set_ops(struct net_devi
void hns_nic_net_reset(struct net_device *ndev);
void hns_nic_net_reinit(struct net_device *netdev);
int hns_nic_init_phy(struct net_device *ndev, struct hnae_handle *h);
-int hns_nic_net_xmit_hw(struct net_device *ndev,
- struct sk_buff *skb,
- struct hns_nic_ring_data *ring_data);
+netdev_tx_t hns_nic_net_xmit_hw(struct net_device *ndev,
+ struct sk_buff *skb,
+ struct hns_nic_ring_data *ring_data);

#endif /**__HNS_ENET_H */