[PATCH 3/8] mwifiex: Fix NULL pointer dereference in skb_dequeue()
From: Amitkumar Karwar <hidden>
Date: 2016-09-28 12:49:31
Subsystem:
marvell mwifiex wireless driver, the rest · Maintainers:
Brian Norris, Linus Torvalds
At couple of places in cleanup path, we are just going through the skb queue and freeing them without unlinking. This leads to a crash when other thread tries to do skb_dequeue() and use already freed node. The problem is freed by unlinking skb before freeing it. Signed-off-by: Amitkumar Karwar <redacted> --- drivers/net/wireless/marvell/mwifiex/cfg80211.c | 4 +++- drivers/net/wireless/marvell/mwifiex/wmm.c | 12 +++++++++--- 2 files changed, 12 insertions(+), 4 deletions(-)
diff --git a/drivers/net/wireless/marvell/mwifiex/cfg80211.c b/drivers/net/wireless/marvell/mwifiex/cfg80211.c
index 39ce76a..e83861f 100644
--- a/drivers/net/wireless/marvell/mwifiex/cfg80211.c
+++ b/drivers/net/wireless/marvell/mwifiex/cfg80211.c@@ -3070,8 +3070,10 @@ int mwifiex_del_virtual_intf(struct wiphy *wiphy, struct wireless_dev *wdev) mwifiex_stop_net_dev_queue(priv->netdev, adapter); - skb_queue_walk_safe(&priv->bypass_txq, skb, tmp) + skb_queue_walk_safe(&priv->bypass_txq, skb, tmp) { + skb_unlink(skb, &priv->bypass_txq); mwifiex_write_data_complete(priv->adapter, skb, 0, -1); + } if (netif_carrier_ok(priv->netdev)) netif_carrier_off(priv->netdev);
diff --git a/drivers/net/wireless/marvell/mwifiex/wmm.c b/drivers/net/wireless/marvell/mwifiex/wmm.c
index 0eb2465..dea2fe6 100644
--- a/drivers/net/wireless/marvell/mwifiex/wmm.c
+++ b/drivers/net/wireless/marvell/mwifiex/wmm.c@@ -503,8 +503,10 @@ mwifiex_wmm_del_pkts_in_ralist_node(struct mwifiex_private *priv, struct mwifiex_adapter *adapter = priv->adapter; struct sk_buff *skb, *tmp; - skb_queue_walk_safe(&ra_list->skb_head, skb, tmp) + skb_queue_walk_safe(&ra_list->skb_head, skb, tmp) { + skb_unlink(skb, &ra_list->skb_head); mwifiex_write_data_complete(adapter, skb, 0, -1); + } } /*
@@ -600,11 +602,15 @@ mwifiex_clean_txrx(struct mwifiex_private *priv) priv->adapter->if_ops.clean_pcie_ring(priv->adapter); spin_unlock_irqrestore(&priv->wmm.ra_list_spinlock, flags); - skb_queue_walk_safe(&priv->tdls_txq, skb, tmp) + skb_queue_walk_safe(&priv->tdls_txq, skb, tmp) { + skb_unlink(skb, &priv->tdls_txq); mwifiex_write_data_complete(priv->adapter, skb, 0, -1); + } - skb_queue_walk_safe(&priv->bypass_txq, skb, tmp) + skb_queue_walk_safe(&priv->bypass_txq, skb, tmp) { + skb_unlink(skb, &priv->bypass_txq); mwifiex_write_data_complete(priv->adapter, skb, 0, -1); + } atomic_set(&priv->adapter->bypass_tx_pending, 0); idr_for_each(&priv->ack_status_frames, mwifiex_free_ack_frame, NULL);
--
1.9.1