p54: fix race condition in memory management

This patch fixes a number of race conditions in the driver.
Up until now, "entry" pointer was initialized before acquiring the right lock.

Signed-off-by: Christian Lamparter <chunkeey@web.de>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
This commit is contained in:
Christian Lamparter 2009-03-06 00:53:59 +01:00 committed by John W. Linville
parent bd05f28e1a
commit c035002472

View File

@ -710,10 +710,11 @@ static struct sk_buff *p54_find_tx_entry(struct ieee80211_hw *dev,
__le32 req_id)
{
struct p54_common *priv = dev->priv;
struct sk_buff *entry = priv->tx_queue.next;
struct sk_buff *entry;
unsigned long flags;
spin_lock_irqsave(&priv->tx_queue.lock, flags);
entry = priv->tx_queue.next;
while (entry != (struct sk_buff *)&priv->tx_queue) {
struct p54_hdr *hdr = (struct p54_hdr *) entry->data;
@ -732,7 +733,7 @@ static void p54_rx_frame_sent(struct ieee80211_hw *dev, struct sk_buff *skb)
struct p54_common *priv = dev->priv;
struct p54_hdr *hdr = (struct p54_hdr *) skb->data;
struct p54_frame_sent *payload = (struct p54_frame_sent *) hdr->data;
struct sk_buff *entry = (struct sk_buff *) priv->tx_queue.next;
struct sk_buff *entry;
u32 addr = le32_to_cpu(hdr->req_id) - priv->headroom;
struct memrecord *range = NULL;
u32 freed = 0;
@ -741,6 +742,7 @@ static void p54_rx_frame_sent(struct ieee80211_hw *dev, struct sk_buff *skb)
int count, idx;
spin_lock_irqsave(&priv->tx_queue.lock, flags);
entry = (struct sk_buff *) priv->tx_queue.next;
while (entry != (struct sk_buff *)&priv->tx_queue) {
struct ieee80211_tx_info *info = IEEE80211_SKB_CB(entry);
struct p54_hdr *entry_hdr;
@ -976,7 +978,7 @@ static int p54_assign_address(struct ieee80211_hw *dev, struct sk_buff *skb,
struct p54_hdr *data, u32 len)
{
struct p54_common *priv = dev->priv;
struct sk_buff *entry = priv->tx_queue.next;
struct sk_buff *entry;
struct sk_buff *target_skb = NULL;
struct ieee80211_tx_info *info;
struct memrecord *range;
@ -1014,6 +1016,7 @@ static int p54_assign_address(struct ieee80211_hw *dev, struct sk_buff *skb,
}
}
entry = priv->tx_queue.next;
while (left--) {
u32 hole_size;
info = IEEE80211_SKB_CB(entry);