When SLUB debugging is enabled in the kernel, and the boot command includes
the option "slub_debug=P", rtl8187 encounters a GPF due to a read-after-free
of a urb.
Following the example of changes in p54usb to fix the same problem, the code
has been modified to use the usb_anchor_urb() method, which avoids the problem.
Signed-off-by: Larry Finger <Larry.Finger@xxxxxxxxxxxx>
---
Index: wireless-testing/drivers/net/wireless/rtl818x/rtl8187.h
===================================================================
--- wireless-testing.orig/drivers/net/wireless/rtl818x/rtl8187.h
+++ wireless-testing/drivers/net/wireless/rtl818x/rtl8187.h
@@ -99,6 +99,7 @@ struct rtl8187_priv {
struct ieee80211_supported_band band;
struct usb_device *udev;
u32 rx_conf;
+ struct usb_anchor anchored;
u16 txpwr_base;
u8 asic_rev;
u8 is_rtl8187b;
@@ -115,7 +116,6 @@ struct rtl8187_priv {
u8 aifsn[4];
struct {
__le64 buf;
- struct urb *urb;
struct sk_buff_head queue;
} b_tx_status;
};
Index: wireless-testing/drivers/net/wireless/rtl818x/rtl8187_dev.c
===================================================================
--- wireless-testing.orig/drivers/net/wireless/rtl818x/rtl8187_dev.c
+++ wireless-testing/drivers/net/wireless/rtl818x/rtl8187_dev.c
@@ -99,7 +99,6 @@ static const struct ieee80211_channel rt
static void rtl8187_iowrite_async_cb(struct urb *urb)
{
kfree(urb->context);
- usb_free_urb(urb);
}
static void rtl8187_iowrite_async(struct rtl8187_priv *priv, __le16 addr,
@@ -136,11 +135,13 @@ static void rtl8187_iowrite_async(struct
usb_fill_control_urb(urb, priv->udev, usb_sndctrlpipe(priv->udev, 0),
(unsigned char *)dr, buf, len,
rtl8187_iowrite_async_cb, buf);
+ usb_anchor_urb(urb, &priv->anchored);
rc = usb_submit_urb(urb, GFP_ATOMIC);
if (rc < 0) {
kfree(buf);
- usb_free_urb(urb);
+ usb_unanchor_urb(urb);
}
+ usb_free_urb(urb);
}
static inline void rtl818x_iowrite32_async(struct rtl8187_priv *priv,
@@ -172,7 +173,6 @@ static void rtl8187_tx_cb(struct urb *ur
struct ieee80211_hw *hw = info->rate_driver_data[0];
struct rtl8187_priv *priv = hw->priv;
- usb_free_urb(info->rate_driver_data[1]);
skb_pull(skb, priv->is_rtl8187b ? sizeof(struct rtl8187b_tx_hdr) :
sizeof(struct rtl8187_tx_hdr));
ieee80211_tx_info_clear_status(info);
@@ -273,11 +273,13 @@ static int rtl8187_tx(struct ieee80211_h
usb_fill_bulk_urb(urb, priv->udev, usb_sndbulkpipe(priv->udev, ep),
buf, skb->len, rtl8187_tx_cb, skb);
+ usb_anchor_urb(urb, &priv->anchored);
rc = usb_submit_urb(urb, GFP_ATOMIC);
if (rc < 0) {
- usb_free_urb(urb);
+ usb_unanchor_urb(urb);
kfree_skb(skb);
}
+ usb_free_urb(urb);
return 0;
}
@@ -301,14 +303,13 @@ static void rtl8187_rx_cb(struct urb *ur
return;
}
spin_unlock(&priv->rx_queue.lock);
+ skb_put(skb, urb->actual_length);
if (unlikely(urb->status)) {
- usb_free_urb(urb);
dev_kfree_skb_irq(skb);
return;
}
- skb_put(skb, urb->actual_length);
if (!priv->is_rtl8187b) {
struct rtl8187_rx_hdr *hdr =
(typeof(hdr))(skb_tail_pointer(skb) - sizeof(*hdr));
@@ -361,7 +362,6 @@ static void rtl8187_rx_cb(struct urb *ur
skb = dev_alloc_skb(RTL8187_MAX_RX);
if (unlikely(!skb)) {
- usb_free_urb(urb);
/* TODO check rx queue length and refill *somewhere* */
return;
}
@@ -373,24 +373,30 @@ static void rtl8187_rx_cb(struct urb *ur
urb->context = skb;
skb_queue_tail(&priv->rx_queue, skb);
- usb_submit_urb(urb, GFP_ATOMIC);
+ usb_anchor_urb(urb, &priv->anchored);
+ if (usb_submit_urb(urb, GFP_ATOMIC))
+ usb_unanchor_urb(urb);
}
static int rtl8187_init_urbs(struct ieee80211_hw *dev)
{
struct rtl8187_priv *priv = dev->priv;
- struct urb *entry;
+ struct urb *entry = NULL;
struct sk_buff *skb;
struct rtl8187_rx_info *info;
+ int ret = 0;
while (skb_queue_len(&priv->rx_queue) < 8) {
skb = __dev_alloc_skb(RTL8187_MAX_RX, GFP_KERNEL);
- if (!skb)
- break;
+ if (!skb) {
+ ret = -ENOMEM;
+ goto err;
+ }
entry = usb_alloc_urb(0, GFP_KERNEL);
if (!entry) {
kfree_skb(skb);
- break;
+ ret = -ENOMEM;
+ goto err;
}
usb_fill_bulk_urb(entry, priv->udev,
usb_rcvbulkpipe(priv->udev,
@@ -401,10 +407,22 @@ static int rtl8187_init_urbs(struct ieee
info->urb = entry;
info->dev = dev;
skb_queue_tail(&priv->rx_queue, skb);
- usb_submit_urb(entry, GFP_KERNEL);
+ usb_anchor_urb(entry, &priv->anchored);
+ ret = usb_submit_urb(entry, GFP_KERNEL);
+ if (ret) {
+ skb_unlink(skb, &priv->rx_queue);
+ usb_unanchor_urb(entry);
+ goto err;
+ }
+ usb_free_urb(entry);
}
+ return ret;
- return 0;
+err:
+ usb_free_urb(entry);
+ kfree_skb(skb);
+ usb_kill_anchored_urbs(&priv->anchored);
+ return ret;
}
static void rtl8187b_status_cb(struct urb *urb)
@@ -415,7 +433,6 @@ static void rtl8187b_status_cb(struct ur
unsigned int cmd_type;
if (unlikely(urb->status)) {
- usb_free_urb(urb);
return;
}
@@ -488,26 +505,32 @@ static void rtl8187b_status_cb(struct ur
spin_unlock_irqrestore(&priv->b_tx_status.queue.lock, flags);
}
- usb_submit_urb(urb, GFP_ATOMIC);
+ usb_anchor_urb(urb, &priv->anchored);
+ if (usb_submit_urb(urb, GFP_ATOMIC))
+ usb_unanchor_urb(urb);
}
static int rtl8187b_init_status_urb(struct ieee80211_hw *dev)
{
struct rtl8187_priv *priv = dev->priv;
struct urb *entry;
+ int ret = 0;
entry = usb_alloc_urb(0, GFP_KERNEL);
if (!entry)
return -ENOMEM;
- priv->b_tx_status.urb = entry;
usb_fill_bulk_urb(entry, priv->udev, usb_rcvbulkpipe(priv->udev, 9),
&priv->b_tx_status.buf, sizeof(priv->b_tx_status.buf),
rtl8187b_status_cb, dev);
- usb_submit_urb(entry, GFP_KERNEL);
+ usb_anchor_urb(entry, &priv->anchored);
+ ret = usb_submit_urb(entry, GFP_KERNEL);
+ if (ret)
+ usb_unanchor_urb(entry);
+ usb_free_urb(entry);
- return 0;
+ return ret;
}
static int rtl8187_cmd_reset(struct ieee80211_hw *dev)
@@ -841,6 +864,9 @@ static int rtl8187_start(struct ieee8021
return ret;
mutex_lock(&priv->conf_mutex);
+
+ init_usb_anchor(&priv->anchored);
+
if (priv->is_rtl8187b) {
reg = RTL818X_RX_CONF_MGMT |
RTL818X_RX_CONF_DATA |
@@ -936,12 +962,12 @@ static void rtl8187_stop(struct ieee8021
while ((skb = skb_dequeue(&priv->rx_queue))) {
info = (struct rtl8187_rx_info *)skb->cb;
- usb_kill_urb(info->urb);
kfree_skb(skb);
}
while ((skb = skb_dequeue(&priv->b_tx_status.queue)))
dev_kfree_skb_any(skb);
- usb_kill_urb(priv->b_tx_status.urb);
+
+ usb_kill_anchored_urbs(&priv->anchored);
mutex_unlock(&priv->conf_mutex);
}
--
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