From 62765d39553cfd1ad340124fe1e280450e8c89e2 Mon Sep 17 00:00:00 2001 From: Jia-Ju Bai Date: Sun, 7 Mar 2021 01:12:56 -0800 Subject: net: wan: fix error return code of uhdlc_init() When priv->rx_skbuff or priv->tx_skbuff is NULL, no error return code of uhdlc_init() is assigned. To fix this bug, ret is assigned with -ENOMEM in these cases. Reported-by: TOTE Robot Signed-off-by: Jia-Ju Bai Signed-off-by: David S. Miller --- drivers/net/wan/fsl_ucc_hdlc.c | 8 ++++++-- 1 file changed, 6 insertions(+), 2 deletions(-) (limited to 'drivers/net/wan') diff --git a/drivers/net/wan/fsl_ucc_hdlc.c b/drivers/net/wan/fsl_ucc_hdlc.c index dca97cd7c4e7..7eac6a3e1cde 100644 --- a/drivers/net/wan/fsl_ucc_hdlc.c +++ b/drivers/net/wan/fsl_ucc_hdlc.c @@ -204,14 +204,18 @@ static int uhdlc_init(struct ucc_hdlc_private *priv) priv->rx_skbuff = kcalloc(priv->rx_ring_size, sizeof(*priv->rx_skbuff), GFP_KERNEL); - if (!priv->rx_skbuff) + if (!priv->rx_skbuff) { + ret = -ENOMEM; goto free_ucc_pram; + } priv->tx_skbuff = kcalloc(priv->tx_ring_size, sizeof(*priv->tx_skbuff), GFP_KERNEL); - if (!priv->tx_skbuff) + if (!priv->tx_skbuff) { + ret = -ENOMEM; goto free_rx_skbuff; + } priv->skb_curtx = 0; priv->skb_dirtytx = 0; -- cgit From f7d9d4854519fdf4d45c70a4d953438cd88e7e58 Mon Sep 17 00:00:00 2001 From: Xie He Date: Sun, 7 Mar 2021 03:33:07 -0800 Subject: net: lapbether: Remove netif_start_queue / netif_stop_queue For the devices in this driver, the default qdisc is "noqueue", because their "tx_queue_len" is 0. In function "__dev_queue_xmit" in "net/core/dev.c", devices with the "noqueue" qdisc are specially handled. Packets are transmitted without being queued after a "dev->flags & IFF_UP" check. However, it's possible that even if this check succeeds, "ops->ndo_stop" may still have already been called. This is because in "__dev_close_many", "ops->ndo_stop" is called before clearing the "IFF_UP" flag. If we call "netif_stop_queue" in "ops->ndo_stop", then it's possible in "__dev_queue_xmit", it sees the "IFF_UP" flag is present, and then it checks "netif_xmit_stopped" and finds that the queue is already stopped. In this case, it will complain that: "Virtual device ... asks to queue packet!" To prevent "__dev_queue_xmit" from generating this complaint, we should not call "netif_stop_queue" in "ops->ndo_stop". We also don't need to call "netif_start_queue" in "ops->ndo_open", because after a netdev is allocated and registered, the "__QUEUE_STATE_DRV_XOFF" flag is initially not set, so there is no need to call "netif_start_queue" to clear it. Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2") Signed-off-by: Xie He Acked-by: Martin Schiller Signed-off-by: David S. Miller --- drivers/net/wan/lapbether.c | 3 --- 1 file changed, 3 deletions(-) (limited to 'drivers/net/wan') diff --git a/drivers/net/wan/lapbether.c b/drivers/net/wan/lapbether.c index 605fe555e157..c3372498f4f1 100644 --- a/drivers/net/wan/lapbether.c +++ b/drivers/net/wan/lapbether.c @@ -292,7 +292,6 @@ static int lapbeth_open(struct net_device *dev) return -ENODEV; } - netif_start_queue(dev); return 0; } @@ -300,8 +299,6 @@ static int lapbeth_close(struct net_device *dev) { int err; - netif_stop_queue(dev); - if ((err = lapb_unregister(dev)) != LAPB_OK) pr_err("lapb_unregister error: %d\n", err); -- cgit From bf0ffea336b493c0a8c8bc27b46683ecf1e8f294 Mon Sep 17 00:00:00 2001 From: Xie He Date: Sun, 14 Mar 2021 04:21:01 -0700 Subject: net: hdlc_x25: Prevent racing between "x25_close" and "x25_xmit"/"x25_rx" "x25_close" is called by "hdlc_close" in "hdlc.c", which is called by hardware drivers' "ndo_stop" function. "x25_xmit" is called by "hdlc_start_xmit" in "hdlc.c", which is hardware drivers' "ndo_start_xmit" function. "x25_rx" is called by "hdlc_rcv" in "hdlc.c", which receives HDLC frames from "net/core/dev.c". "x25_close" races with "x25_xmit" and "x25_rx" because their callers race. However, we need to ensure that the LAPB APIs called in "x25_xmit" and "x25_rx" are called before "lapb_unregister" is called in "x25_close". This patch adds locking to ensure when "x25_xmit" and "x25_rx" are doing their work, "lapb_unregister" is not yet called in "x25_close". Reasons for not solving the racing between "x25_close" and "x25_xmit" by calling "netif_tx_disable" in "x25_close": 1. We still need to solve the racing between "x25_close" and "x25_rx"; 2. The design of the HDLC subsystem assumes the HDLC hardware drivers have full control over the TX queue, and the HDLC protocol drivers (like this driver) have no control. Controlling the queue here in the protocol driver may interfere with hardware drivers' control of the queue. Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2") Signed-off-by: Xie He Signed-off-by: David S. Miller --- drivers/net/wan/hdlc_x25.c | 42 +++++++++++++++++++++++++++++++++++++++++- 1 file changed, 41 insertions(+), 1 deletion(-) (limited to 'drivers/net/wan') diff --git a/drivers/net/wan/hdlc_x25.c b/drivers/net/wan/hdlc_x25.c index 4aaa6388b9ee..5a6a945f6c81 100644 --- a/drivers/net/wan/hdlc_x25.c +++ b/drivers/net/wan/hdlc_x25.c @@ -23,6 +23,8 @@ struct x25_state { x25_hdlc_proto settings; + bool up; + spinlock_t up_lock; /* Protects "up" */ }; static int x25_ioctl(struct net_device *dev, struct ifreq *ifr); @@ -104,6 +106,8 @@ static void x25_data_transmit(struct net_device *dev, struct sk_buff *skb) static netdev_tx_t x25_xmit(struct sk_buff *skb, struct net_device *dev) { + hdlc_device *hdlc = dev_to_hdlc(dev); + struct x25_state *x25st = state(hdlc); int result; /* There should be a pseudo header of 1 byte added by upper layers. @@ -114,11 +118,19 @@ static netdev_tx_t x25_xmit(struct sk_buff *skb, struct net_device *dev) return NETDEV_TX_OK; } + spin_lock_bh(&x25st->up_lock); + if (!x25st->up) { + spin_unlock_bh(&x25st->up_lock); + kfree_skb(skb); + return NETDEV_TX_OK; + } + switch (skb->data[0]) { case X25_IFACE_DATA: /* Data to be transmitted */ skb_pull(skb, 1); if ((result = lapb_data_request(dev, skb)) != LAPB_OK) dev_kfree_skb(skb); + spin_unlock_bh(&x25st->up_lock); return NETDEV_TX_OK; case X25_IFACE_CONNECT: @@ -147,6 +159,7 @@ static netdev_tx_t x25_xmit(struct sk_buff *skb, struct net_device *dev) break; } + spin_unlock_bh(&x25st->up_lock); dev_kfree_skb(skb); return NETDEV_TX_OK; } @@ -164,6 +177,7 @@ static int x25_open(struct net_device *dev) .data_transmit = x25_data_transmit, }; hdlc_device *hdlc = dev_to_hdlc(dev); + struct x25_state *x25st = state(hdlc); struct lapb_parms_struct params; int result; @@ -190,6 +204,10 @@ static int x25_open(struct net_device *dev) if (result != LAPB_OK) return -EINVAL; + spin_lock_bh(&x25st->up_lock); + x25st->up = true; + spin_unlock_bh(&x25st->up_lock); + return 0; } @@ -197,6 +215,13 @@ static int x25_open(struct net_device *dev) static void x25_close(struct net_device *dev) { + hdlc_device *hdlc = dev_to_hdlc(dev); + struct x25_state *x25st = state(hdlc); + + spin_lock_bh(&x25st->up_lock); + x25st->up = false; + spin_unlock_bh(&x25st->up_lock); + lapb_unregister(dev); } @@ -205,15 +230,28 @@ static void x25_close(struct net_device *dev) static int x25_rx(struct sk_buff *skb) { struct net_device *dev = skb->dev; + hdlc_device *hdlc = dev_to_hdlc(dev); + struct x25_state *x25st = state(hdlc); if ((skb = skb_share_check(skb, GFP_ATOMIC)) == NULL) { dev->stats.rx_dropped++; return NET_RX_DROP; } - if (lapb_data_received(dev, skb) == LAPB_OK) + spin_lock_bh(&x25st->up_lock); + if (!x25st->up) { + spin_unlock_bh(&x25st->up_lock); + kfree_skb(skb); + dev->stats.rx_dropped++; + return NET_RX_DROP; + } + + if (lapb_data_received(dev, skb) == LAPB_OK) { + spin_unlock_bh(&x25st->up_lock); return NET_RX_SUCCESS; + } + spin_unlock_bh(&x25st->up_lock); dev->stats.rx_errors++; dev_kfree_skb_any(skb); return NET_RX_DROP; @@ -298,6 +336,8 @@ static int x25_ioctl(struct net_device *dev, struct ifreq *ifr) return result; memcpy(&state(hdlc)->settings, &new_settings, size); + state(hdlc)->up = false; + spin_lock_init(&state(hdlc)->up_lock); /* There's no header_ops so hard_header_len should be 0. */ dev->hard_header_len = 0; -- cgit From 1b479fb801602b22512f53c19b1f93a4fc5d5d9d Mon Sep 17 00:00:00 2001 From: Lv Yunlong Date: Sun, 28 Mar 2021 00:50:08 -0700 Subject: drivers/net/wan/hdlc_fr: Fix a double free in pvc_xmit In pvc_xmit, if __skb_pad(skb, pad, false) failed, it will free the skb in the first time and goto drop. But the same skb is freed by kfree_skb(skb) in the second time in drop. Maintaining the original function unchanged, my patch adds a new label out to avoid the double free if __skb_pad() failed. Fixes: f5083d0cee08a ("drivers/net/wan/hdlc_fr: Improvements to the code of pvc_xmit") Signed-off-by: Lv Yunlong Signed-off-by: David S. Miller --- drivers/net/wan/hdlc_fr.c | 5 +++-- 1 file changed, 3 insertions(+), 2 deletions(-) (limited to 'drivers/net/wan') diff --git a/drivers/net/wan/hdlc_fr.c b/drivers/net/wan/hdlc_fr.c index 0720f5f92caa..4d9dc7d15908 100644 --- a/drivers/net/wan/hdlc_fr.c +++ b/drivers/net/wan/hdlc_fr.c @@ -415,7 +415,7 @@ static netdev_tx_t pvc_xmit(struct sk_buff *skb, struct net_device *dev) if (pad > 0) { /* Pad the frame with zeros */ if (__skb_pad(skb, pad, false)) - goto drop; + goto out; skb_put(skb, pad); } } @@ -448,8 +448,9 @@ static netdev_tx_t pvc_xmit(struct sk_buff *skb, struct net_device *dev) return NETDEV_TX_OK; drop: - dev->stats.tx_dropped++; kfree_skb(skb); +out: + dev->stats.tx_dropped++; return NETDEV_TX_OK; } -- cgit