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From:   Luiz Augusto von Dentz <luiz.dentz@gmail.com>
To:     linux-bluetooth@vger.kernel.org
Subject: [PATCH] Bluetooth: hci_core: Fix not handling link timeouts propertly
Date:   Mon, 26 Sep 2022 15:51:07 -0700
Message-Id: <20220926225107.3226470-1-luiz.dentz@gmail.com>
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From: Luiz Augusto von Dentz <luiz.von.dentz@intel.com>

Change that introduced the use of __check_timeout did not account for
link types properly, it always assumes ACL_LINK is used thus causing
hdev->acl_last_tx to be used even in case of LE_LINK and then again
uses ACL_LINK with hci_link_tx_to.

To fix this __check_timeout now takes the link type as parameter and
then procedure to use the right last_tx based on the link type and pass
it to hci_link_tx_to.

Fixes: 1b1d29e51499 ("Bluetooth: Make use of __check_timeout on hci_sched_le")
Signed-off-by: Luiz Augusto von Dentz <luiz.von.dentz@intel.com>
---
 net/bluetooth/hci_core.c | 34 +++++++++++++++++++++++-----------
 1 file changed, 23 insertions(+), 11 deletions(-)

diff --git a/net/bluetooth/hci_core.c b/net/bluetooth/hci_core.c
index 66c7cdba0d32..063fbb8e07ca 100644
--- a/net/bluetooth/hci_core.c
+++ b/net/bluetooth/hci_core.c
@@ -3485,15 +3485,27 @@ static inline int __get_blocks(struct hci_dev *hdev, struct sk_buff *skb)
 	return DIV_ROUND_UP(skb->len - HCI_ACL_HDR_SIZE, hdev->block_len);
 }
 
-static void __check_timeout(struct hci_dev *hdev, unsigned int cnt)
+static void __check_timeout(struct hci_dev *hdev, unsigned int cnt, u8 type)
 {
-	if (!hci_dev_test_flag(hdev, HCI_UNCONFIGURED)) {
-		/* ACL tx timeout must be longer than maximum
-		 * link supervision timeout (40.9 seconds) */
-		if (!cnt && time_after(jiffies, hdev->acl_last_tx +
-				       HCI_ACL_TX_TIMEOUT))
-			hci_link_tx_to(hdev, ACL_LINK);
+	unsigned long last_tx;
+
+	if (hci_dev_test_flag(hdev, HCI_UNCONFIGURED))
+		return;
+
+	switch (type) {
+	case LE_LINK:
+		last_tx = hdev->le_last_tx;
+		break;
+	default:
+		last_tx = hdev->acl_last_tx;
+		break;
 	}
+
+	/* tx timeout must be longer than maximum link supervision timeout
+	 * (40.9 seconds)
+	 */
+	if (!cnt && time_after(jiffies, last_tx + HCI_ACL_TX_TIMEOUT))
+		hci_link_tx_to(hdev, type);
 }
 
 /* Schedule SCO */
@@ -3551,7 +3563,7 @@ static void hci_sched_acl_pkt(struct hci_dev *hdev)
 	struct sk_buff *skb;
 	int quote;
 
-	__check_timeout(hdev, cnt);
+	__check_timeout(hdev, cnt, ACL_LINK);
 
 	while (hdev->acl_cnt &&
 	       (chan = hci_chan_sent(hdev, ACL_LINK, &quote))) {
@@ -3594,8 +3606,6 @@ static void hci_sched_acl_blk(struct hci_dev *hdev)
 	int quote;
 	u8 type;
 
-	__check_timeout(hdev, cnt);
-
 	BT_DBG("%s", hdev->name);
 
 	if (hdev->dev_type == HCI_AMP)
@@ -3603,6 +3613,8 @@ static void hci_sched_acl_blk(struct hci_dev *hdev)
 	else
 		type = ACL_LINK;
 
+	__check_timeout(hdev, cnt, type);
+
 	while (hdev->block_cnt > 0 &&
 	       (chan = hci_chan_sent(hdev, type, &quote))) {
 		u32 priority = (skb_peek(&chan->data_q))->priority;
@@ -3676,7 +3688,7 @@ static void hci_sched_le(struct hci_dev *hdev)
 
 	cnt = hdev->le_pkts ? hdev->le_cnt : hdev->acl_cnt;
 
-	__check_timeout(hdev, cnt);
+	__check_timeout(hdev, cnt, LE_LINK);
 
 	tmp = cnt;
 	while (cnt && (chan = hci_chan_sent(hdev, LE_LINK, &quote))) {
-- 
2.37.3