ath10k: fix potential null dereference bugs

Smatch warns about a number of cases in ath10k where a pointer is
null-checked after it has already been dereferenced, in code involving
ath10k private virtual interface pointers.

Fix these by making the dereference happen later.

Addresses the following smatch warnings:

drivers/net/wireless/ath/ath10k/mac.c:3651 ath10k_mac_txq_init() warn: variable dereferenced before check 'txq' (see line 3649)
drivers/net/wireless/ath/ath10k/mac.c:3664 ath10k_mac_txq_unref() warn: variable dereferenced before check 'txq' (see line 3659)
drivers/net/wireless/ath/ath10k/htt_tx.c:70 __ath10k_htt_tx_txq_recalc() warn: variable dereferenced before check 'txq->sta' (see line 52)
drivers/net/wireless/ath/ath10k/htt_tx.c:740 ath10k_htt_tx_get_vdev_id() warn: variable dereferenced before check 'cb->vif' (see line 736)
drivers/net/wireless/ath/ath10k/txrx.c:86 ath10k_txrx_tx_unref() warn: variable dereferenced before check 'txq' (see line 84)
drivers/net/wireless/ath/ath10k/wmi.c:1837 ath10k_wmi_op_gen_mgmt_tx() warn: variable dereferenced before check 'cb->vif' (see line 1825)

Signed-off-by: Bob Copeland <me@bobcopeland.com>
Signed-off-by: Kalle Valo <kvalo@qca.qualcomm.com>
This commit is contained in:
Bob Copeland 2016-06-29 19:29:25 +03:00 committed by Kalle Valo
parent 569fba2cbb
commit a66cd733a7
4 changed files with 24 additions and 15 deletions

View File

@ -49,7 +49,7 @@ static void __ath10k_htt_tx_txq_recalc(struct ieee80211_hw *hw,
struct ieee80211_txq *txq)
{
struct ath10k *ar = hw->priv;
struct ath10k_sta *arsta = (void *)txq->sta->drv_priv;
struct ath10k_sta *arsta;
struct ath10k_vif *arvif = (void *)txq->vif->drv_priv;
unsigned long frame_cnt;
unsigned long byte_cnt;
@ -67,10 +67,12 @@ static void __ath10k_htt_tx_txq_recalc(struct ieee80211_hw *hw,
if (ar->htt.tx_q_state.mode != HTT_TX_MODE_SWITCH_PUSH_PULL)
return;
if (txq->sta)
if (txq->sta) {
arsta = (void *)txq->sta->drv_priv;
peer_id = arsta->peer_id;
else
} else {
peer_id = arvif->peer_id;
}
tid = txq->tid;
bit = BIT(peer_id % 32);
@ -733,16 +735,18 @@ static u8 ath10k_htt_tx_get_vdev_id(struct ath10k *ar, struct sk_buff *skb)
{
struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb);
struct ath10k_skb_cb *cb = ATH10K_SKB_CB(skb);
struct ath10k_vif *arvif = (void *)cb->vif->drv_priv;
struct ath10k_vif *arvif;
if (info->flags & IEEE80211_TX_CTL_TX_OFFCHAN)
if (info->flags & IEEE80211_TX_CTL_TX_OFFCHAN) {
return ar->scan.vdev_id;
else if (cb->vif)
} else if (cb->vif) {
arvif = (void *)cb->vif->drv_priv;
return arvif->vdev_id;
else if (ar->monitor_started)
} else if (ar->monitor_started) {
return ar->monitor_vdev_id;
else
} else {
return 0;
}
}
static u8 ath10k_htt_tx_get_tid(struct sk_buff *skb, bool is_eth)

View File

@ -3675,17 +3675,18 @@ void ath10k_mgmt_over_wmi_tx_work(struct work_struct *work)
static void ath10k_mac_txq_init(struct ieee80211_txq *txq)
{
struct ath10k_txq *artxq = (void *)txq->drv_priv;
struct ath10k_txq *artxq;
if (!txq)
return;
artxq = (void *)txq->drv_priv;
INIT_LIST_HEAD(&artxq->list);
}
static void ath10k_mac_txq_unref(struct ath10k *ar, struct ieee80211_txq *txq)
{
struct ath10k_txq *artxq = (void *)txq->drv_priv;
struct ath10k_txq *artxq;
struct ath10k_skb_cb *cb;
struct sk_buff *msdu;
int msdu_id;
@ -3693,6 +3694,7 @@ static void ath10k_mac_txq_unref(struct ath10k *ar, struct ieee80211_txq *txq)
if (!txq)
return;
artxq = (void *)txq->drv_priv;
spin_lock_bh(&ar->txqs_lock);
if (!list_empty(&artxq->list))
list_del_init(&artxq->list);

View File

@ -81,10 +81,11 @@ int ath10k_txrx_tx_unref(struct ath10k_htt *htt,
skb_cb = ATH10K_SKB_CB(msdu);
txq = skb_cb->txq;
artxq = (void *)txq->drv_priv;
if (txq)
if (txq) {
artxq = (void *)txq->drv_priv;
artxq->num_fw_queued--;
}
ath10k_htt_tx_free_msdu_id(htt, tx_done->msdu_id);
ath10k_htt_tx_dec_pending(htt);

View File

@ -1826,7 +1826,7 @@ static struct sk_buff *
ath10k_wmi_op_gen_mgmt_tx(struct ath10k *ar, struct sk_buff *msdu)
{
struct ath10k_skb_cb *cb = ATH10K_SKB_CB(msdu);
struct ath10k_vif *arvif = (void *)cb->vif->drv_priv;
struct ath10k_vif *arvif;
struct wmi_mgmt_tx_cmd *cmd;
struct ieee80211_hdr *hdr;
struct sk_buff *skb;
@ -1838,10 +1838,12 @@ ath10k_wmi_op_gen_mgmt_tx(struct ath10k *ar, struct sk_buff *msdu)
hdr = (struct ieee80211_hdr *)msdu->data;
fc = le16_to_cpu(hdr->frame_control);
if (cb->vif)
if (cb->vif) {
arvif = (void *)cb->vif->drv_priv;
vdev_id = arvif->vdev_id;
else
} else {
vdev_id = 0;
}
if (WARN_ON_ONCE(!ieee80211_is_mgmt(hdr->frame_control)))
return ERR_PTR(-EINVAL);