Staging driver fixes for 5.17-rc8

Here are 3 small fixes for staging drivers for 5.17-rc8 or -final, which
 ever comes next.
 
 They resolve some reported problems:
 	- rtl8723bs wifi driver deadlock fix for reported problem that
 	  is a revert of a previous patch.  Also a documentation fix is
 	  added so that the same problem hopefully can not come back
 	  again.
 	- gdm724x driver use-after-free fix for a reported problem.
 
 All of these have been in linux-next for a while with no reported
 problems.
 
 Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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Merge tag 'staging-5.17-rc8' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/staging

Pull staging driver fixes from Greg KH:
 "Here are three small fixes for staging drivers for 5.17-rc8 or -final,
  which ever comes next.

  They resolve some reported problems:

   - rtl8723bs wifi driver deadlock fix for reported problem that is a
     revert of a previous patch. Also a documentation fix is added so
     that the same problem hopefully can not come back again.

   - gdm724x driver use-after-free fix for a reported problem.

  All of these have been in linux-next for a while with no reported
  problems"

* tag 'staging-5.17-rc8' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/staging:
  staging: rtl8723bs: Improve the comment explaining the locking rules
  staging: rtl8723bs: Fix access-point mode deadlock
  staging: gdm724x: fix use after free in gdm_lte_rx()

drivers/staging/gdm724x/gdm_lte.c

@@ -76,14 +76,15 @@ static void tx_complete(void *arg)
 
 static int gdm_lte_rx(struct sk_buff *skb, struct nic *nic, int nic_type)
 {
-	int ret;
+	int ret, len;
 
+	len = skb->len + ETH_HLEN;
 	ret = netif_rx_ni(skb);
 	if (ret == NET_RX_DROP) {
 		nic->stats.rx_dropped++;
 	} else {
 		nic->stats.rx_packets++;
-		nic->stats.rx_bytes += skb->len + ETH_HLEN;
+		nic->stats.rx_bytes += len;
 	}
 
 	return 0;

drivers/staging/rtl8723bs/core/rtw_mlme_ext.c

@@ -5907,6 +5907,7 @@ u8 chk_bmc_sleepq_hdl(struct adapter *padapter, unsigned char *pbuf)
 	struct sta_info *psta_bmc;
 	struct list_head *xmitframe_plist, *xmitframe_phead, *tmp;
 	struct xmit_frame *pxmitframe = NULL;
+	struct xmit_priv *pxmitpriv = &padapter->xmitpriv;
 	struct sta_priv  *pstapriv = &padapter->stapriv;
 
 	/* for BC/MC Frames */
@@ -5917,7 +5918,8 @@ u8 chk_bmc_sleepq_hdl(struct adapter *padapter, unsigned char *pbuf)
 	if ((pstapriv->tim_bitmap&BIT(0)) && (psta_bmc->sleepq_len > 0)) {
 		msleep(10);/*  10ms, ATIM(HIQ) Windows */
 
-		spin_lock_bh(&psta_bmc->sleep_q.lock);
+		/* spin_lock_bh(&psta_bmc->sleep_q.lock); */
+		spin_lock_bh(&pxmitpriv->lock);
 
 		xmitframe_phead = get_list_head(&psta_bmc->sleep_q);
 		list_for_each_safe(xmitframe_plist, tmp, xmitframe_phead) {
@@ -5940,7 +5942,8 @@ u8 chk_bmc_sleepq_hdl(struct adapter *padapter, unsigned char *pbuf)
 			rtw_hal_xmitframe_enqueue(padapter, pxmitframe);
 		}
 
-		spin_unlock_bh(&psta_bmc->sleep_q.lock);
+		/* spin_unlock_bh(&psta_bmc->sleep_q.lock); */
+		spin_unlock_bh(&pxmitpriv->lock);
 
 		/* check hi queue and bmc_sleepq */
 		rtw_chk_hi_queue_cmd(padapter);

drivers/staging/rtl8723bs/core/rtw_recv.c

@@ -957,8 +957,10 @@ static signed int validate_recv_ctrl_frame(struct adapter *padapter, union recv_
 		if ((psta->state&WIFI_SLEEP_STATE) && (pstapriv->sta_dz_bitmap&BIT(psta->aid))) {
 			struct list_head	*xmitframe_plist, *xmitframe_phead;
 			struct xmit_frame *pxmitframe = NULL;
+			struct xmit_priv *pxmitpriv = &padapter->xmitpriv;
 
-			spin_lock_bh(&psta->sleep_q.lock);
+			/* spin_lock_bh(&psta->sleep_q.lock); */
+			spin_lock_bh(&pxmitpriv->lock);
 
 			xmitframe_phead = get_list_head(&psta->sleep_q);
 			xmitframe_plist = get_next(xmitframe_phead);
@@ -989,10 +991,12 @@ static signed int validate_recv_ctrl_frame(struct adapter *padapter, union recv_
 					update_beacon(padapter, WLAN_EID_TIM, NULL, true);
 				}
 
-				spin_unlock_bh(&psta->sleep_q.lock);
+				/* spin_unlock_bh(&psta->sleep_q.lock); */
+				spin_unlock_bh(&pxmitpriv->lock);
 
 			} else {
-				spin_unlock_bh(&psta->sleep_q.lock);
+				/* spin_unlock_bh(&psta->sleep_q.lock); */
+				spin_unlock_bh(&pxmitpriv->lock);
 
 				if (pstapriv->tim_bitmap&BIT(psta->aid)) {
 					if (psta->sleepq_len == 0) {

drivers/staging/rtl8723bs/core/rtw_sta_mgt.c

@@ -293,48 +293,46 @@ u32 rtw_free_stainfo(struct adapter *padapter, struct sta_info *psta)
 
 	/* list_del_init(&psta->wakeup_list); */
 
-	spin_lock_bh(&psta->sleep_q.lock);
-	rtw_free_xmitframe_queue(pxmitpriv, &psta->sleep_q);
-	psta->sleepq_len = 0;
-	spin_unlock_bh(&psta->sleep_q.lock);
-
 	spin_lock_bh(&pxmitpriv->lock);
 
+	rtw_free_xmitframe_queue(pxmitpriv, &psta->sleep_q);
+	psta->sleepq_len = 0;
+
 	/* vo */
-	spin_lock_bh(&pstaxmitpriv->vo_q.sta_pending.lock);
+	/* spin_lock_bh(&(pxmitpriv->vo_pending.lock)); */
 	rtw_free_xmitframe_queue(pxmitpriv, &pstaxmitpriv->vo_q.sta_pending);
 	list_del_init(&(pstaxmitpriv->vo_q.tx_pending));
 	phwxmit = pxmitpriv->hwxmits;
 	phwxmit->accnt -= pstaxmitpriv->vo_q.qcnt;
 	pstaxmitpriv->vo_q.qcnt = 0;
-	spin_unlock_bh(&pstaxmitpriv->vo_q.sta_pending.lock);
+	/* spin_unlock_bh(&(pxmitpriv->vo_pending.lock)); */
 
 	/* vi */
-	spin_lock_bh(&pstaxmitpriv->vi_q.sta_pending.lock);
+	/* spin_lock_bh(&(pxmitpriv->vi_pending.lock)); */
 	rtw_free_xmitframe_queue(pxmitpriv, &pstaxmitpriv->vi_q.sta_pending);
 	list_del_init(&(pstaxmitpriv->vi_q.tx_pending));
 	phwxmit = pxmitpriv->hwxmits+1;
 	phwxmit->accnt -= pstaxmitpriv->vi_q.qcnt;
 	pstaxmitpriv->vi_q.qcnt = 0;
-	spin_unlock_bh(&pstaxmitpriv->vi_q.sta_pending.lock);
+	/* spin_unlock_bh(&(pxmitpriv->vi_pending.lock)); */
 
 	/* be */
-	spin_lock_bh(&pstaxmitpriv->be_q.sta_pending.lock);
+	/* spin_lock_bh(&(pxmitpriv->be_pending.lock)); */
 	rtw_free_xmitframe_queue(pxmitpriv, &pstaxmitpriv->be_q.sta_pending);
 	list_del_init(&(pstaxmitpriv->be_q.tx_pending));
 	phwxmit = pxmitpriv->hwxmits+2;
 	phwxmit->accnt -= pstaxmitpriv->be_q.qcnt;
 	pstaxmitpriv->be_q.qcnt = 0;
-	spin_unlock_bh(&pstaxmitpriv->be_q.sta_pending.lock);
+	/* spin_unlock_bh(&(pxmitpriv->be_pending.lock)); */
 
 	/* bk */
-	spin_lock_bh(&pstaxmitpriv->bk_q.sta_pending.lock);
+	/* spin_lock_bh(&(pxmitpriv->bk_pending.lock)); */
 	rtw_free_xmitframe_queue(pxmitpriv, &pstaxmitpriv->bk_q.sta_pending);
 	list_del_init(&(pstaxmitpriv->bk_q.tx_pending));
 	phwxmit = pxmitpriv->hwxmits+3;
 	phwxmit->accnt -= pstaxmitpriv->bk_q.qcnt;
 	pstaxmitpriv->bk_q.qcnt = 0;
-	spin_unlock_bh(&pstaxmitpriv->bk_q.sta_pending.lock);
+	/* spin_unlock_bh(&(pxmitpriv->bk_pending.lock)); */
 
 	spin_unlock_bh(&pxmitpriv->lock);
 

drivers/staging/rtl8723bs/core/rtw_xmit.c

@@ -1734,12 +1734,15 @@ void rtw_free_xmitframe_queue(struct xmit_priv *pxmitpriv, struct __queue *pfram
 	struct list_head *plist, *phead, *tmp;
 	struct	xmit_frame	*pxmitframe;
 
+	spin_lock_bh(&pframequeue->lock);
+
 	phead = get_list_head(pframequeue);
 	list_for_each_safe(plist, tmp, phead) {
 		pxmitframe = list_entry(plist, struct xmit_frame, list);
 
 		rtw_free_xmitframe(pxmitpriv, pxmitframe);
 	}
+	spin_unlock_bh(&pframequeue->lock);
 }
 
 s32 rtw_xmitframe_enqueue(struct adapter *padapter, struct xmit_frame *pxmitframe)
@@ -1794,7 +1797,6 @@ s32 rtw_xmit_classifier(struct adapter *padapter, struct xmit_frame *pxmitframe)
 	struct sta_info *psta;
 	struct tx_servq	*ptxservq;
 	struct pkt_attrib	*pattrib = &pxmitframe->attrib;
-	struct xmit_priv *xmit_priv = &padapter->xmitpriv;
 	struct hw_xmit	*phwxmits =  padapter->xmitpriv.hwxmits;
 	signed int res = _SUCCESS;
 
@@ -1812,14 +1814,12 @@ s32 rtw_xmit_classifier(struct adapter *padapter, struct xmit_frame *pxmitframe)
 
 	ptxservq = rtw_get_sta_pending(padapter, psta, pattrib->priority, (u8 *)(&ac_index));
 
-	spin_lock_bh(&xmit_priv->lock);
 	if (list_empty(&ptxservq->tx_pending))
 		list_add_tail(&ptxservq->tx_pending, get_list_head(phwxmits[ac_index].sta_queue));
 
 	list_add_tail(&pxmitframe->list, get_list_head(&ptxservq->sta_pending));
 	ptxservq->qcnt++;
 	phwxmits[ac_index].accnt++;
-	spin_unlock_bh(&xmit_priv->lock);
 
 exit:
 
@@ -2202,10 +2202,11 @@ void wakeup_sta_to_xmit(struct adapter *padapter, struct sta_info *psta)
 	struct list_head *xmitframe_plist, *xmitframe_phead, *tmp;
 	struct xmit_frame *pxmitframe = NULL;
 	struct sta_priv *pstapriv = &padapter->stapriv;
+	struct xmit_priv *pxmitpriv = &padapter->xmitpriv;
 
 	psta_bmc = rtw_get_bcmc_stainfo(padapter);
 
-	spin_lock_bh(&psta->sleep_q.lock);
+	spin_lock_bh(&pxmitpriv->lock);
 
 	xmitframe_phead = get_list_head(&psta->sleep_q);
 	list_for_each_safe(xmitframe_plist, tmp, xmitframe_phead) {
@@ -2306,7 +2307,7 @@ void wakeup_sta_to_xmit(struct adapter *padapter, struct sta_info *psta)
 
 _exit:
 
-	spin_unlock_bh(&psta->sleep_q.lock);
+	spin_unlock_bh(&pxmitpriv->lock);
 
 	if (update_mask)
 		update_beacon(padapter, WLAN_EID_TIM, NULL, true);
@@ -2318,8 +2319,9 @@ void xmit_delivery_enabled_frames(struct adapter *padapter, struct sta_info *pst
 	struct list_head *xmitframe_plist, *xmitframe_phead, *tmp;
 	struct xmit_frame *pxmitframe = NULL;
 	struct sta_priv *pstapriv = &padapter->stapriv;
+	struct xmit_priv *pxmitpriv = &padapter->xmitpriv;
 
-	spin_lock_bh(&psta->sleep_q.lock);
+	spin_lock_bh(&pxmitpriv->lock);
 
 	xmitframe_phead = get_list_head(&psta->sleep_q);
 	list_for_each_safe(xmitframe_plist, tmp, xmitframe_phead) {
@@ -2372,7 +2374,7 @@ void xmit_delivery_enabled_frames(struct adapter *padapter, struct sta_info *pst
 		}
 	}
 
-	spin_unlock_bh(&psta->sleep_q.lock);
+	spin_unlock_bh(&pxmitpriv->lock);
 }
 
 void enqueue_pending_xmitbuf(struct xmit_priv *pxmitpriv, struct xmit_buf *pxmitbuf)

drivers/staging/rtl8723bs/hal/rtl8723bs_xmit.c

@@ -502,7 +502,9 @@ s32 rtl8723bs_hal_xmit(
 			rtw_issue_addbareq_cmd(padapter, pxmitframe);
 	}
 
+	spin_lock_bh(&pxmitpriv->lock);
 	err = rtw_xmitframe_enqueue(padapter, pxmitframe);
+	spin_unlock_bh(&pxmitpriv->lock);
 	if (err != _SUCCESS) {
 		rtw_free_xmitframe(pxmitpriv, pxmitframe);
 

drivers/staging/rtl8723bs/include/rtw_mlme.h

@@ -102,13 +102,17 @@ there are several "locks" in mlme_priv,
 since mlme_priv is a shared resource between many threads,
 like ISR/Call-Back functions, the OID handlers, and even timer functions.
 
-
 Each struct __queue has its own locks, already.
-Other items are protected by mlme_priv.lock.
+Other items in mlme_priv are protected by mlme_priv.lock, while items in
+xmit_priv are protected by xmit_priv.lock.
 
 To avoid possible dead lock, any thread trying to modifiying mlme_priv
 SHALL not lock up more than one locks at a time!
 
+The only exception is that queue functions which take the __queue.lock
+may be called with the xmit_priv.lock held. In this case the order
+MUST always be first lock xmit_priv.lock and then call any queue functions
+which take __queue.lock.
 */