FAILED: patch "[PATCH] Bluetooth: hci_conn: Fix null ptr deref in hci_abort_conn()" failed to apply to 6.12-stable tree

FAILED: patch "[PATCH] Bluetooth: hci_conn: Fix null ptr deref in hci_abort_conn()" failed to apply to 6.12-stable tree

[gregkh]

The patch below does not apply to the 6.12-stable tree.
If someone wants it applied there, or to any other stable or longterm
tree, then please email the backport, including the original git commit
id to <stable@vger.kernel.org>.

To reproduce the conflict and resubmit, you may use the following commands:

git fetch https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/ linux-6.12.y
git checkout FETCH_HEAD
git cherry-pick -x 12917f591cea1af36087dba5b9ec888652f0b42a
# <resolve conflicts, build, test, etc.>
git commit -s
git send-email --to '<stable@vger.kernel.org>' --in-reply-to '2026071353-angular-magical-b4f5@gregkh' --subject-prefix 'PATCH 6.12.y' 'HEAD^..'

Possible dependencies:



thanks,

greg k-h

------------------ original commit in Linus's tree ------------------

From 12917f591cea1af36087dba5b9ec888652f0b42a Mon Sep 17 00:00:00 2001
From: Siwei Zhang <oss@fourdim.xyz>
Date: Mon, 15 Jun 2026 11:33:05 -0400
Subject: [PATCH] Bluetooth: hci_conn: Fix null ptr deref in hci_abort_conn()

hci_abort_conn() read hci_skb_event(hdev->sent_cmd) when a connection
was pending, but hdev->sent_cmd can be NULL while req_status is still
HCI_REQ_PEND, leading to a NULL pointer dereference and a general
protection fault from the hci_rx_work() receive path.

Instead of inspecting hdev->sent_cmd, track the in-flight create
connection command with a new per-connection HCI_CONN_CREATE flag and
route all cancellation through hci_cancel_connect_sync(), which
dispatches to a dedicated per-type cancel function. The create command
is in exactly one of two states: still queued, or in flight. The cancel
function holds cmd_sync_work_lock across the whole decision: the worker
takes this lock to dequeue every entry, so while it is held a queued
command cannot start running and an in-flight command cannot complete
and let the next command become pending. This keeps the flag test and
hci_cmd_sync_cancel() atomic with respect to the worker, so a queued
command is simply dequeued, and an in-flight command owned by this
connection is cancelled without the risk of cancelling an unrelated
command that became pending in the meantime. CIS uses the same flag
mechanism via HCI_CONN_CREATE_CIS but cannot be dequeued per-connection.

hci_acl_create_conn_sync() and hci_le_create_conn_sync() clear
HCI_CONN_CREATE after the create command completes, but the command
status handler can free conn via hci_conn_del() (for example when the
controller rejects the connection) while the worker is still blocked on
the connection complete event. Hold a reference on conn across the
create command so the flag can be cleared without a use-after-free.

Fixes: a13f316e90fd ("Bluetooth: hci_conn: Consolidate code for aborting connections")
Cc: stable@vger.kernel.org
Suggested-by: XIAO WU <xiaowu.417@qq.com>
Assisted-by: Claude:claude-opus-4-8
Signed-off-by: Siwei Zhang <oss@fourdim.xyz>
Signed-off-by: Luiz Augusto von Dentz <luiz.von.dentz@intel.com>

diff --git a/include/net/bluetooth/hci_core.h b/include/net/bluetooth/hci_core.h
index 7e15da47fe3a..4ca09298e11a 100644
--- a/include/net/bluetooth/hci_core.h
+++ b/include/net/bluetooth/hci_core.h
@@ -985,6 +985,7 @@ enum {
 	HCI_CONN_AUTH_FAILURE,
 	HCI_CONN_PER_ADV,
 	HCI_CONN_BIG_CREATED,
+	HCI_CONN_CREATE,
 	HCI_CONN_CREATE_CIS,
 	HCI_CONN_CREATE_BIG_SYNC,
 	HCI_CONN_BIG_SYNC,
diff --git a/net/bluetooth/hci_conn.c b/net/bluetooth/hci_conn.c
index c335372e4062..1966cd153d97 100644
--- a/net/bluetooth/hci_conn.c
+++ b/net/bluetooth/hci_conn.c
@@ -3178,26 +3178,11 @@ int hci_abort_conn(struct hci_conn *conn, u8 reason)
 
 	conn->abort_reason = reason;
 
-	/* If the connection is pending check the command opcode since that
-	 * might be blocking on hci_cmd_sync_work while waiting its respective
-	 * event so we need to hci_cmd_sync_cancel to cancel it.
-	 *
-	 * hci_connect_le serializes the connection attempts so only one
-	 * connection can be in BT_CONNECT at time.
+	/* Cancel the connect attempt. A return of 0 means the create command
+	 * was still queued and got dequeued, so there is nothing to disconnect.
 	 */
-	if (conn->state == BT_CONNECT && READ_ONCE(hdev->req_status) == HCI_REQ_PEND) {
-		switch (hci_skb_event(hdev->sent_cmd)) {
-		case HCI_EV_CONN_COMPLETE:
-		case HCI_EV_LE_CONN_COMPLETE:
-		case HCI_EV_LE_ENHANCED_CONN_COMPLETE:
-		case HCI_EVT_LE_CIS_ESTABLISHED:
-			hci_cmd_sync_cancel(hdev, ECANCELED);
-			break;
-		}
-	/* Cancel connect attempt if still queued/pending */
-	} else if (!hci_cancel_connect_sync(hdev, conn)) {
+	if (!hci_cancel_connect_sync(hdev, conn))
 		return 0;
-	}
 
 	/* Run immediately if on cmd_sync_work since this may be called
 	 * as a result to MGMT_OP_DISCONNECT/MGMT_OP_UNPAIR which does
diff --git a/net/bluetooth/hci_sync.c b/net/bluetooth/hci_sync.c
index 3be8c3581c6c..c896d4edd013 100644
--- a/net/bluetooth/hci_sync.c
+++ b/net/bluetooth/hci_sync.c
@@ -6633,6 +6633,11 @@ static int hci_le_create_conn_sync(struct hci_dev *hdev, void *data)
 
 	bt_dev_dbg(hdev, "conn %p", conn);
 
+	/* Hold a reference so conn stays valid for the HCI_CONN_CREATE
+	 * clear_bit() at done.
+	 */
+	hci_conn_get(conn);
+
 	clear_bit(HCI_CONN_SCANNING, &conn->flags);
 	conn->state = BT_CONNECT;
 
@@ -6645,6 +6650,7 @@ static int hci_le_create_conn_sync(struct hci_dev *hdev, void *data)
 		    hdev->le_scan_type == LE_SCAN_ACTIVE &&
 		    !hci_dev_test_flag(hdev, HCI_LE_SIMULTANEOUS_ROLES)) {
 			hci_conn_del(conn);
+			hci_conn_put(conn);
 			return -EBUSY;
 		}
 
@@ -6690,6 +6696,12 @@ static int hci_le_create_conn_sync(struct hci_dev *hdev, void *data)
 					     &own_addr_type);
 	if (err)
 		goto done;
+
+	/* Mark create connection in flight so hci_cancel_connect_sync() can
+	 * cancel it while blocking on the connection complete event.
+	 */
+	set_bit(HCI_CONN_CREATE, &conn->flags);
+
 	/* Send command LE Extended Create Connection if supported */
 	if (use_ext_conn(hdev)) {
 		err = hci_le_ext_create_conn_sync(hdev, conn, own_addr_type);
@@ -6725,11 +6737,14 @@ static int hci_le_create_conn_sync(struct hci_dev *hdev, void *data)
 				       conn->conn_timeout, NULL);
 
 done:
+	clear_bit(HCI_CONN_CREATE, &conn->flags);
+
 	if (err == -ETIMEDOUT)
 		hci_le_connect_cancel_sync(hdev, conn, 0x00);
 
 	/* Re-enable advertising after the connection attempt is finished. */
 	hci_resume_advertising_sync(hdev);
+	hci_conn_put(conn);
 	return err;
 }
 
@@ -7004,10 +7019,25 @@ static int hci_acl_create_conn_sync(struct hci_dev *hdev, void *data)
 	else
 		cp.role_switch = 0x00;
 
-	return __hci_cmd_sync_status_sk(hdev, HCI_OP_CREATE_CONN,
-					sizeof(cp), &cp,
-					HCI_EV_CONN_COMPLETE,
-					conn->conn_timeout, NULL);
+	/* Hold a reference so conn stays valid for the HCI_CONN_CREATE
+	 * clear_bit() below.
+	 */
+	hci_conn_get(conn);
+
+	/* Mark create connection in flight so hci_cancel_connect_sync() can
+	 * cancel it while blocking on the connection complete event.
+	 */
+	set_bit(HCI_CONN_CREATE, &conn->flags);
+
+	err = __hci_cmd_sync_status_sk(hdev, HCI_OP_CREATE_CONN,
+				       sizeof(cp), &cp,
+				       HCI_EV_CONN_COMPLETE,
+				       conn->conn_timeout, NULL);
+
+	clear_bit(HCI_CONN_CREATE, &conn->flags);
+	hci_conn_put(conn);
+
+	return err;
 }
 
 int hci_connect_acl_sync(struct hci_dev *hdev, struct hci_conn *conn)
@@ -7059,22 +7089,97 @@ int hci_connect_le_sync(struct hci_dev *hdev, struct hci_conn *conn)
 	return (err == -EEXIST) ? 0 : err;
 }
 
-int hci_cancel_connect_sync(struct hci_dev *hdev, struct hci_conn *conn)
+static int hci_acl_cancel_create_conn_sync(struct hci_dev *hdev,
+					   struct hci_conn *conn)
 {
-	if (conn->state != BT_OPEN)
-		return -EINVAL;
+	struct hci_cmd_sync_work_entry *entry;
+	int err = -EBUSY;
 
-	switch (conn->type) {
-	case ACL_LINK:
-		return !hci_cmd_sync_dequeue_once(hdev,
-						  hci_acl_create_conn_sync,
-						  conn, NULL);
-	case LE_LINK:
-		return !hci_cmd_sync_dequeue_once(hdev, hci_le_create_conn_sync,
-						  conn, create_le_conn_complete);
+	/* cmd_sync_work_lock makes the HCI_CONN_CREATE test and the cancel
+	 * atomic against the worker, which takes this lock to dequeue every
+	 * entry: while it is held no other command can become pending, so
+	 * hci_cmd_sync_cancel() cannot cancel an unrelated command.
+	 */
+	mutex_lock(&hdev->cmd_sync_work_lock);
+
+	/* In flight: this connection owns the pending request, cancel it. */
+	if (test_bit(HCI_CONN_CREATE, &conn->flags)) {
+		hci_cmd_sync_cancel(hdev, ECANCELED);
+		goto unlock;
 	}
 
-	return -ENOENT;
+	/* Still queued: a successful dequeue means it never started, so there
+	 * is nothing to disconnect.
+	 */
+	entry = _hci_cmd_sync_lookup_entry(hdev, hci_acl_create_conn_sync, conn,
+					   NULL);
+	if (entry) {
+		_hci_cmd_sync_cancel_entry(hdev, entry, -ECANCELED);
+		err = 0;
+	}
+
+unlock:
+	mutex_unlock(&hdev->cmd_sync_work_lock);
+	return err;
+}
+
+static int hci_le_cancel_create_conn_sync(struct hci_dev *hdev,
+					  struct hci_conn *conn)
+{
+	struct hci_cmd_sync_work_entry *entry;
+	int err = -EBUSY;
+
+	/* cmd_sync_work_lock keeps the HCI_CONN_CREATE test and the cancel
+	 * atomic against the cmd_sync worker.
+	 */
+	mutex_lock(&hdev->cmd_sync_work_lock);
+
+	if (test_bit(HCI_CONN_CREATE, &conn->flags)) {
+		hci_cmd_sync_cancel(hdev, ECANCELED);
+		goto unlock;
+	}
+
+	entry = _hci_cmd_sync_lookup_entry(hdev, hci_le_create_conn_sync, conn,
+					   create_le_conn_complete);
+	if (entry) {
+		_hci_cmd_sync_cancel_entry(hdev, entry, -ECANCELED);
+		err = 0;
+	}
+
+unlock:
+	mutex_unlock(&hdev->cmd_sync_work_lock);
+	return err;
+}
+
+static int hci_cis_cancel_create_conn_sync(struct hci_dev *hdev,
+					   struct hci_conn *conn)
+{
+	/* LE Create CIS is shared by the whole CIG and cannot be dequeued
+	 * per-connection, so only an in-flight command can be cancelled.
+	 * cmd_sync_work_lock keeps the test and the cancel atomic against the
+	 * cmd_sync worker.
+	 */
+	mutex_lock(&hdev->cmd_sync_work_lock);
+
+	if (test_bit(HCI_CONN_CREATE_CIS, &conn->flags))
+		hci_cmd_sync_cancel(hdev, ECANCELED);
+
+	mutex_unlock(&hdev->cmd_sync_work_lock);
+	return -EBUSY;
+}
+
+int hci_cancel_connect_sync(struct hci_dev *hdev, struct hci_conn *conn)
+{
+	switch (conn->type) {
+	case ACL_LINK:
+		return hci_acl_cancel_create_conn_sync(hdev, conn);
+	case LE_LINK:
+		return hci_le_cancel_create_conn_sync(hdev, conn);
+	case CIS_LINK:
+		return hci_cis_cancel_create_conn_sync(hdev, conn);
+	default:
+		return -ENOENT;
+	}
 }
 
 int hci_le_conn_update_sync(struct hci_dev *hdev, struct hci_conn *conn,

[PATCH 6.12.y 1/3] Bluetooth: hci_core: Enable buffer flow control for SCO/eSCO

[Sasha Levin]

From: Luiz Augusto von Dentz <luiz.von.dentz@intel.com>

[ Upstream commit 13218453521d75916dfed55efb8e809bfc03cb4b ]

This enables buffer flow control for SCO/eSCO
(see: Bluetooth Core 6.0 spec: 6.22. Synchronous Flow Control Enable),
recently this has caused the following problem and is actually a nice
addition for the likes of Socket TX complete:

< HCI Command: Read Buffer Size (0x04|0x0005) plen 0
> HCI Event: Command Complete (0x0e) plen 11
      Read Buffer Size (0x04|0x0005) ncmd 1
        Status: Success (0x00)
        ACL MTU: 1021 ACL max packet: 5
        SCO MTU: 240  SCO max packet: 8
...
< SCO Data TX: Handle 257 flags 0x00 dlen 120
< SCO Data TX: Handle 257 flags 0x00 dlen 120
< SCO Data TX: Handle 257 flags 0x00 dlen 120
< SCO Data TX: Handle 257 flags 0x00 dlen 120
< SCO Data TX: Handle 257 flags 0x00 dlen 120
< SCO Data TX: Handle 257 flags 0x00 dlen 120
< SCO Data TX: Handle 257 flags 0x00 dlen 120
< SCO Data TX: Handle 257 flags 0x00 dlen 120
< SCO Data TX: Handle 257 flags 0x00 dlen 120
> HCI Event: Hardware Error (0x10) plen 1
        Code: 0x0a

To fix the code will now attempt to enable buffer flow control when
HCI_QUIRK_SYNC_FLOWCTL_SUPPORTED is set by the driver:

< HCI Command: Write Sync Fl.. (0x03|0x002f) plen 1
        Flow control: Enabled (0x01)
> HCI Event: Command Complete (0x0e) plen 4
      Write Sync Flow Control Enable (0x03|0x002f) ncmd 1
        Status: Success (0x00)

On success then HCI_SCO_FLOWCTL would be set which indicates sco_cnt
shall be used for flow contro.

Fixes: 7fedd3bb6b77 ("Bluetooth: Prioritize SCO traffic")
Signed-off-by: Luiz Augusto von Dentz <luiz.von.dentz@intel.com>
Tested-by: Pauli Virtanen <pav@iki.fi>
Stable-dep-of: 12917f591cea ("Bluetooth: hci_conn: Fix null ptr deref in hci_abort_conn()")
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
 include/net/bluetooth/hci.h      | 13 +++++++
 include/net/bluetooth/hci_core.h |  1 +
 net/bluetooth/hci_core.c         | 62 +++++++++++++++-----------------
 net/bluetooth/hci_event.c        |  2 ++
 net/bluetooth/hci_sync.c         | 24 +++++++++++++
 5 files changed, 68 insertions(+), 34 deletions(-)

diff --git a/include/net/bluetooth/hci.h b/include/net/bluetooth/hci.h
index 999ac27050993b..39f6f0d67d7012 100644
--- a/include/net/bluetooth/hci.h
+++ b/include/net/bluetooth/hci.h
@@ -207,6 +207,13 @@ enum {
 	 */
 	HCI_QUIRK_WIDEBAND_SPEECH_SUPPORTED,
 
+	/* When this quirk is set consider Sync Flow Control as supported by
+	 * the driver.
+	 *
+	 * This quirk must be set before hci_register_dev is called.
+	 */
+	HCI_QUIRK_SYNC_FLOWCTL_SUPPORTED,
+
 	/* When this quirk is set, the LE states reported through the
 	 * HCI_LE_READ_SUPPORTED_STATES are invalid/broken.
 	 *
@@ -448,6 +455,7 @@ enum {
 	HCI_WIDEBAND_SPEECH_ENABLED,
 	HCI_EVENT_FILTER_CONFIGURED,
 	HCI_PA_SYNC,
+	HCI_SCO_FLOWCTL,
 
 	HCI_DUT_MODE,
 	HCI_VENDOR_DIAG,
@@ -1545,6 +1553,11 @@ struct hci_rp_read_tx_power {
 	__s8     tx_power;
 } __packed;
 
+#define HCI_OP_WRITE_SYNC_FLOWCTL	0x0c2f
+struct hci_cp_write_sync_flowctl {
+	__u8     enable;
+} __packed;
+
 #define HCI_OP_READ_PAGE_SCAN_TYPE	0x0c46
 struct hci_rp_read_page_scan_type {
 	__u8     status;
diff --git a/include/net/bluetooth/hci_core.h b/include/net/bluetooth/hci_core.h
index a0c84a83f25eb1..5b738a76779f00 100644
--- a/include/net/bluetooth/hci_core.h
+++ b/include/net/bluetooth/hci_core.h
@@ -1891,6 +1891,7 @@ void hci_conn_del_sysfs(struct hci_conn *conn);
 #define lmp_hold_capable(dev)      ((dev)->features[0][0] & LMP_HOLD)
 #define lmp_sniff_capable(dev)     ((dev)->features[0][0] & LMP_SNIFF)
 #define lmp_park_capable(dev)      ((dev)->features[0][1] & LMP_PARK)
+#define lmp_sco_capable(dev)       ((dev)->features[0][1] & LMP_SCO)
 #define lmp_inq_rssi_capable(dev)  ((dev)->features[0][3] & LMP_RSSI_INQ)
 #define lmp_esco_capable(dev)      ((dev)->features[0][3] & LMP_ESCO)
 #define lmp_bredr_capable(dev)     (!((dev)->features[0][4] & LMP_NO_BREDR))
diff --git a/net/bluetooth/hci_core.c b/net/bluetooth/hci_core.c
index e96ccdd7ef15e7..d53487bcd712c5 100644
--- a/net/bluetooth/hci_core.c
+++ b/net/bluetooth/hci_core.c
@@ -3606,42 +3606,27 @@ static void __check_timeout(struct hci_dev *hdev, unsigned int cnt, u8 type)
 }
 
 /* Schedule SCO */
-static void hci_sched_sco(struct hci_dev *hdev)
+static void hci_sched_sco(struct hci_dev *hdev, __u8 type)
 {
 	struct hci_conn *conn;
 	struct sk_buff *skb;
-	int quote;
+	int quote, *cnt;
+	unsigned int pkts = hdev->sco_pkts;
 
-	BT_DBG("%s", hdev->name);
+	bt_dev_dbg(hdev, "type %u", type);
 
-	if (!hci_conn_num(hdev, SCO_LINK))
+	if (!hci_conn_num(hdev, type) || !pkts)
 		return;
 
-	while (hdev->sco_cnt && (conn = hci_low_sent(hdev, SCO_LINK, &quote))) {
-		while (quote-- && (skb = skb_dequeue(&conn->data_q))) {
-			BT_DBG("skb %p len %d", skb, skb->len);
-			hci_send_frame(hdev, skb);
-
-			conn->sent++;
-			if (conn->sent == ~0)
-				conn->sent = 0;
-		}
-	}
-}
-
-static void hci_sched_esco(struct hci_dev *hdev)
-{
-	struct hci_conn *conn;
-	struct sk_buff *skb;
-	int quote;
-
-	BT_DBG("%s", hdev->name);
-
-	if (!hci_conn_num(hdev, ESCO_LINK))
-		return;
+	/* Use sco_pkts if flow control has not been enabled which will limit
+	 * the amount of buffer sent in a row.
+	 */
+	if (!hci_dev_test_flag(hdev, HCI_SCO_FLOWCTL))
+		cnt = &pkts;
+	else
+		cnt = &hdev->sco_cnt;
 
-	while (hdev->sco_cnt && (conn = hci_low_sent(hdev, ESCO_LINK,
-						     &quote))) {
+	while (*cnt && (conn = hci_low_sent(hdev, type, &quote))) {
 		while (quote-- && (skb = skb_dequeue(&conn->data_q))) {
 			BT_DBG("skb %p len %d", skb, skb->len);
 			hci_send_frame(hdev, skb);
@@ -3649,8 +3634,17 @@ static void hci_sched_esco(struct hci_dev *hdev)
 			conn->sent++;
 			if (conn->sent == ~0)
 				conn->sent = 0;
+			(*cnt)--;
 		}
 	}
+
+	/* Rescheduled if all packets were sent and flow control is not enabled
+	 * as there could be more packets queued that could not be sent and
+	 * since no HCI_EV_NUM_COMP_PKTS event will be generated the reschedule
+	 * needs to be forced.
+	 */
+	if (!pkts && !hci_dev_test_flag(hdev, HCI_SCO_FLOWCTL))
+		queue_work(hdev->workqueue, &hdev->tx_work);
 }
 
 static void hci_sched_acl_pkt(struct hci_dev *hdev)
@@ -3686,8 +3680,8 @@ static void hci_sched_acl_pkt(struct hci_dev *hdev)
 			chan->conn->sent++;
 
 			/* Send pending SCO packets right away */
-			hci_sched_sco(hdev);
-			hci_sched_esco(hdev);
+			hci_sched_sco(hdev, SCO_LINK);
+			hci_sched_sco(hdev, ESCO_LINK);
 		}
 	}
 
@@ -3742,8 +3736,8 @@ static void hci_sched_le(struct hci_dev *hdev)
 			chan->conn->sent++;
 
 			/* Send pending SCO packets right away */
-			hci_sched_sco(hdev);
-			hci_sched_esco(hdev);
+			hci_sched_sco(hdev, SCO_LINK);
+			hci_sched_sco(hdev, ESCO_LINK);
 		}
 	}
 
@@ -3788,8 +3782,8 @@ static void hci_tx_work(struct work_struct *work)
 
 	if (!hci_dev_test_flag(hdev, HCI_USER_CHANNEL)) {
 		/* Schedule queues and send stuff to HCI driver */
-		hci_sched_sco(hdev);
-		hci_sched_esco(hdev);
+		hci_sched_sco(hdev, SCO_LINK);
+		hci_sched_sco(hdev, ESCO_LINK);
 		hci_sched_iso(hdev);
 		hci_sched_acl(hdev);
 		hci_sched_le(hdev);
diff --git a/net/bluetooth/hci_event.c b/net/bluetooth/hci_event.c
index 92270b99ee0f2a..47ad62f10cef38 100644
--- a/net/bluetooth/hci_event.c
+++ b/net/bluetooth/hci_event.c
@@ -4448,9 +4448,11 @@ static void hci_num_comp_pkts_evt(struct hci_dev *hdev, void *data,
 			break;
 
 		case SCO_LINK:
+		case ESCO_LINK:
 			hdev->sco_cnt += count;
 			if (hdev->sco_cnt > hdev->sco_pkts)
 				hdev->sco_cnt = hdev->sco_pkts;
+
 			break;
 
 		case ISO_LINK:
diff --git a/net/bluetooth/hci_sync.c b/net/bluetooth/hci_sync.c
index 9e5c26c41f6e91..f6b70ed93c6210 100644
--- a/net/bluetooth/hci_sync.c
+++ b/net/bluetooth/hci_sync.c
@@ -3888,6 +3888,28 @@ static int hci_write_ca_timeout_sync(struct hci_dev *hdev)
 				     sizeof(param), &param, HCI_CMD_TIMEOUT);
 }
 
+/* Enable SCO flow control if supported */
+static int hci_write_sync_flowctl_sync(struct hci_dev *hdev)
+{
+	struct hci_cp_write_sync_flowctl cp;
+	int err;
+
+	/* Check if the controller supports SCO and HCI_OP_WRITE_SYNC_FLOWCTL */
+	if (!lmp_sco_capable(hdev) || !(hdev->commands[10] & BIT(4)) ||
+	    !test_bit(HCI_QUIRK_SYNC_FLOWCTL_SUPPORTED, &hdev->quirks))
+		return 0;
+
+	memset(&cp, 0, sizeof(cp));
+	cp.enable = 0x01;
+
+	err = __hci_cmd_sync_status(hdev, HCI_OP_WRITE_SYNC_FLOWCTL,
+				    sizeof(cp), &cp, HCI_CMD_TIMEOUT);
+	if (!err)
+		hci_dev_set_flag(hdev, HCI_SCO_FLOWCTL);
+
+	return err;
+}
+
 /* BR Controller init stage 2 command sequence */
 static const struct hci_init_stage br_init2[] = {
 	/* HCI_OP_READ_BUFFER_SIZE */
@@ -3906,6 +3928,8 @@ static const struct hci_init_stage br_init2[] = {
 	HCI_INIT(hci_clear_event_filter_sync),
 	/* HCI_OP_WRITE_CA_TIMEOUT */
 	HCI_INIT(hci_write_ca_timeout_sync),
+	/* HCI_OP_WRITE_SYNC_FLOWCTL */
+	HCI_INIT(hci_write_sync_flowctl_sync),
 	{}
 };
 
-- 
2.53.0

[PATCH 6.12.y 2/3] Bluetooth: separate CIS_LINK and BIS_LINK link types

[Sasha Levin]

From: Pauli Virtanen <pav@iki.fi>

[ Upstream commit 23205562ffc8de20f57afdd984858cab29e77968 ]

Use separate link type id for unicast and broadcast ISO connections.
These connection types are handled with separate HCI commands, socket
API is different, and hci_conn has union fields that are different in
the two cases, so they shall not be mixed up.

Currently in most places it is attempted to distinguish ucast by
bacmp(&c->dst, BDADDR_ANY) but it is wrong as dst is set for bcast sink
hci_conn in iso_conn_ready(). Additionally checking sync_handle might be
OK, but depends on details of bcast conn configuration flow.

To avoid complicating it, use separate link types.

Fixes: f764a6c2c1e4 ("Bluetooth: ISO: Add broadcast support")
Signed-off-by: Pauli Virtanen <pav@iki.fi>
Signed-off-by: Luiz Augusto von Dentz <luiz.von.dentz@intel.com>
Stable-dep-of: 12917f591cea ("Bluetooth: hci_conn: Fix null ptr deref in hci_abort_conn()")
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
 include/net/bluetooth/hci.h      |  3 +-
 include/net/bluetooth/hci_core.h | 48 ++++++++++++++------------------
 net/bluetooth/hci_conn.c         | 41 ++++++++++++++++-----------
 net/bluetooth/hci_core.c         | 21 ++++++++------
 net/bluetooth/hci_event.c        | 24 ++++++++--------
 net/bluetooth/hci_sync.c         | 16 +++++++----
 net/bluetooth/iso.c              |  4 +--
 net/bluetooth/mgmt.c             |  3 +-
 8 files changed, 87 insertions(+), 73 deletions(-)

diff --git a/include/net/bluetooth/hci.h b/include/net/bluetooth/hci.h
index 39f6f0d67d7012..673cf9e0cc3bba 100644
--- a/include/net/bluetooth/hci.h
+++ b/include/net/bluetooth/hci.h
@@ -558,7 +558,8 @@ enum {
 #define ESCO_LINK	0x02
 /* Low Energy links do not have defined link type. Use invented one */
 #define LE_LINK		0x80
-#define ISO_LINK	0x82
+#define CIS_LINK	0x82
+#define BIS_LINK	0x83
 #define INVALID_LINK	0xff
 
 /* LMP features */
diff --git a/include/net/bluetooth/hci_core.h b/include/net/bluetooth/hci_core.h
index 5b738a76779f00..ab2cf7489ce783 100644
--- a/include/net/bluetooth/hci_core.h
+++ b/include/net/bluetooth/hci_core.h
@@ -998,7 +998,8 @@ static inline void hci_conn_hash_add(struct hci_dev *hdev, struct hci_conn *c)
 	case ESCO_LINK:
 		h->sco_num++;
 		break;
-	case ISO_LINK:
+	case CIS_LINK:
+	case BIS_LINK:
 		h->iso_num++;
 		break;
 	}
@@ -1024,7 +1025,8 @@ static inline void hci_conn_hash_del(struct hci_dev *hdev, struct hci_conn *c)
 	case ESCO_LINK:
 		h->sco_num--;
 		break;
-	case ISO_LINK:
+	case CIS_LINK:
+	case BIS_LINK:
 		h->iso_num--;
 		break;
 	}
@@ -1041,7 +1043,8 @@ static inline unsigned int hci_conn_num(struct hci_dev *hdev, __u8 type)
 	case SCO_LINK:
 	case ESCO_LINK:
 		return h->sco_num;
-	case ISO_LINK:
+	case CIS_LINK:
+	case BIS_LINK:
 		return h->iso_num;
 	default:
 		return 0;
@@ -1102,7 +1105,7 @@ static inline struct hci_conn *hci_conn_hash_lookup_bis(struct hci_dev *hdev,
 	rcu_read_lock();
 
 	list_for_each_entry_rcu(c, &h->list, list) {
-		if (bacmp(&c->dst, ba) || c->type != ISO_LINK)
+		if (bacmp(&c->dst, ba) || c->type != BIS_LINK)
 			continue;
 
 		if (c->iso_qos.bcast.bis == bis) {
@@ -1124,7 +1127,7 @@ hci_conn_hash_lookup_create_pa_sync(struct hci_dev *hdev)
 	rcu_read_lock();
 
 	list_for_each_entry_rcu(c, &h->list, list) {
-		if (c->type != ISO_LINK)
+		if (c->type != BIS_LINK)
 			continue;
 
 		if (!test_bit(HCI_CONN_CREATE_PA_SYNC, &c->flags))
@@ -1150,8 +1153,8 @@ hci_conn_hash_lookup_per_adv_bis(struct hci_dev *hdev,
 	rcu_read_lock();
 
 	list_for_each_entry_rcu(c, &h->list, list) {
-		if (bacmp(&c->dst, ba) || c->type != ISO_LINK ||
-			!test_bit(HCI_CONN_PER_ADV, &c->flags))
+		if (bacmp(&c->dst, ba) || c->type != BIS_LINK ||
+		    !test_bit(HCI_CONN_PER_ADV, &c->flags))
 			continue;
 
 		if (c->iso_qos.bcast.big == big &&
@@ -1261,7 +1264,7 @@ static inline struct hci_conn *hci_conn_hash_lookup_cis(struct hci_dev *hdev,
 	rcu_read_lock();
 
 	list_for_each_entry_rcu(c, &h->list, list) {
-		if (c->type != ISO_LINK || !bacmp(&c->dst, BDADDR_ANY))
+		if (c->type != CIS_LINK)
 			continue;
 
 		/* Match CIG ID if set */
@@ -1293,7 +1296,7 @@ static inline struct hci_conn *hci_conn_hash_lookup_cig(struct hci_dev *hdev,
 	rcu_read_lock();
 
 	list_for_each_entry_rcu(c, &h->list, list) {
-		if (c->type != ISO_LINK || !bacmp(&c->dst, BDADDR_ANY))
+		if (c->type != CIS_LINK)
 			continue;
 
 		if (handle == c->iso_qos.ucast.cig) {
@@ -1316,17 +1319,7 @@ static inline struct hci_conn *hci_conn_hash_lookup_big(struct hci_dev *hdev,
 	rcu_read_lock();
 
 	list_for_each_entry_rcu(c, &h->list, list) {
-		if (c->type != ISO_LINK)
-			continue;
-
-		/* An ISO_LINK hcon with BDADDR_ANY as destination
-		 * address is a Broadcast connection. A Broadcast
-		 * slave connection is associated with a PA train,
-		 * so the sync_handle can be used to differentiate
-		 * from unicast.
-		 */
-		if (bacmp(&c->dst, BDADDR_ANY) &&
-		    c->sync_handle == HCI_SYNC_HANDLE_INVALID)
+		if (c->type != BIS_LINK)
 			continue;
 
 		if (handle == c->iso_qos.bcast.big) {
@@ -1350,7 +1343,7 @@ hci_conn_hash_lookup_big_sync_pend(struct hci_dev *hdev,
 	rcu_read_lock();
 
 	list_for_each_entry_rcu(c, &h->list, list) {
-		if (c->type != ISO_LINK)
+		if (c->type != BIS_LINK)
 			continue;
 
 		if (handle == c->iso_qos.bcast.big && num_bis == c->num_bis) {
@@ -1373,8 +1366,8 @@ hci_conn_hash_lookup_big_state(struct hci_dev *hdev, __u8 handle,  __u16 state)
 	rcu_read_lock();
 
 	list_for_each_entry_rcu(c, &h->list, list) {
-		if (bacmp(&c->dst, BDADDR_ANY) || c->type != ISO_LINK ||
-			c->state != state)
+		if (c->type != BIS_LINK || bacmp(&c->dst, BDADDR_ANY) ||
+		    c->state != state)
 			continue;
 
 		if (handle == c->iso_qos.bcast.big) {
@@ -1397,8 +1390,8 @@ hci_conn_hash_lookup_pa_sync_big_handle(struct hci_dev *hdev, __u8 big)
 	rcu_read_lock();
 
 	list_for_each_entry_rcu(c, &h->list, list) {
-		if (c->type != ISO_LINK ||
-			!test_bit(HCI_CONN_PA_SYNC, &c->flags))
+		if (c->type != BIS_LINK ||
+		    !test_bit(HCI_CONN_PA_SYNC, &c->flags))
 			continue;
 
 		if (c->iso_qos.bcast.big == big) {
@@ -1420,7 +1413,7 @@ hci_conn_hash_lookup_pa_sync_handle(struct hci_dev *hdev, __u16 sync_handle)
 	rcu_read_lock();
 
 	list_for_each_entry_rcu(c, &h->list, list) {
-		if (c->type != ISO_LINK)
+		if (c->type != BIS_LINK)
 			continue;
 
 		/* Ignore the listen hcon, we are looking
@@ -2030,7 +2023,8 @@ static inline int hci_proto_connect_ind(struct hci_dev *hdev, bdaddr_t *bdaddr,
 	case ESCO_LINK:
 		return sco_connect_ind(hdev, bdaddr, flags);
 
-	case ISO_LINK:
+	case CIS_LINK:
+	case BIS_LINK:
 		return iso_connect_ind(hdev, bdaddr, flags);
 
 	default:
diff --git a/net/bluetooth/hci_conn.c b/net/bluetooth/hci_conn.c
index d34c66b92fbc1b..2e7a2e60d8133d 100644
--- a/net/bluetooth/hci_conn.c
+++ b/net/bluetooth/hci_conn.c
@@ -785,7 +785,7 @@ static int hci_le_big_terminate(struct hci_dev *hdev, u8 big, struct hci_conn *c
 	d->sync_handle = conn->sync_handle;
 
 	if (test_and_clear_bit(HCI_CONN_PA_SYNC, &conn->flags)) {
-		hci_conn_hash_list_flag(hdev, find_bis, ISO_LINK,
+		hci_conn_hash_list_flag(hdev, find_bis, BIS_LINK,
 					HCI_CONN_PA_SYNC, d);
 
 		if (!d->count)
@@ -795,7 +795,7 @@ static int hci_le_big_terminate(struct hci_dev *hdev, u8 big, struct hci_conn *c
 	}
 
 	if (test_and_clear_bit(HCI_CONN_BIG_SYNC, &conn->flags)) {
-		hci_conn_hash_list_flag(hdev, find_bis, ISO_LINK,
+		hci_conn_hash_list_flag(hdev, find_bis, BIS_LINK,
 					HCI_CONN_BIG_SYNC, d);
 
 		if (!d->count)
@@ -885,9 +885,11 @@ static void cis_cleanup(struct hci_conn *conn)
 	/* Check if ISO connection is a CIS and remove CIG if there are
 	 * no other connections using it.
 	 */
-	hci_conn_hash_list_state(hdev, find_cis, ISO_LINK, BT_BOUND, &d);
-	hci_conn_hash_list_state(hdev, find_cis, ISO_LINK, BT_CONNECT, &d);
-	hci_conn_hash_list_state(hdev, find_cis, ISO_LINK, BT_CONNECTED, &d);
+	hci_conn_hash_list_state(hdev, find_cis, CIS_LINK, BT_BOUND, &d);
+	hci_conn_hash_list_state(hdev, find_cis, CIS_LINK, BT_CONNECT,
+				 &d);
+	hci_conn_hash_list_state(hdev, find_cis, CIS_LINK, BT_CONNECTED,
+				 &d);
 	if (d.count)
 		return;
 
@@ -910,7 +912,8 @@ static struct hci_conn *__hci_conn_add(struct hci_dev *hdev, int type, bdaddr_t
 		if (!hdev->acl_mtu)
 			return ERR_PTR(-ECONNREFUSED);
 		break;
-	case ISO_LINK:
+	case CIS_LINK:
+	case BIS_LINK:
 		if (hdev->iso_mtu)
 			/* Dedicated ISO Buffer exists */
 			break;
@@ -975,7 +978,8 @@ static struct hci_conn *__hci_conn_add(struct hci_dev *hdev, int type, bdaddr_t
 		hci_copy_identity_address(hdev, &conn->src, &conn->src_type);
 		conn->mtu = hdev->le_mtu ? hdev->le_mtu : hdev->acl_mtu;
 		break;
-	case ISO_LINK:
+	case CIS_LINK:
+	case BIS_LINK:
 		/* conn->src should reflect the local identity address */
 		hci_copy_identity_address(hdev, &conn->src, &conn->src_type);
 
@@ -1071,7 +1075,8 @@ static void hci_conn_cleanup_child(struct hci_conn *conn, u8 reason)
 		if (HCI_CONN_HANDLE_UNSET(conn->handle))
 			hci_conn_failed(conn, reason);
 		break;
-	case ISO_LINK:
+	case CIS_LINK:
+	case BIS_LINK:
 		if ((conn->state != BT_CONNECTED &&
 		    !test_bit(HCI_CONN_CREATE_CIS, &conn->flags)) ||
 		    test_bit(HCI_CONN_BIG_CREATED, &conn->flags))
@@ -1146,7 +1151,8 @@ void hci_conn_del(struct hci_conn *conn)
 			hdev->acl_cnt += conn->sent;
 	} else {
 		/* Unacked ISO frames */
-		if (conn->type == ISO_LINK) {
+		if (conn->type == CIS_LINK ||
+		    conn->type == BIS_LINK) {
 			if (hdev->iso_pkts)
 				hdev->iso_cnt += conn->sent;
 			else if (hdev->le_pkts)
@@ -1531,7 +1537,7 @@ static struct hci_conn *hci_add_bis(struct hci_dev *hdev, bdaddr_t *dst,
 		     memcmp(conn->le_per_adv_data, base, base_len)))
 		return ERR_PTR(-EADDRINUSE);
 
-	conn = hci_conn_add_unset(hdev, ISO_LINK, dst, HCI_ROLE_MASTER);
+	conn = hci_conn_add_unset(hdev, BIS_LINK, dst, HCI_ROLE_MASTER);
 	if (IS_ERR(conn))
 		return conn;
 
@@ -1740,7 +1746,7 @@ static int hci_le_create_big(struct hci_conn *conn, struct bt_iso_qos *qos)
 	data.count = 0;
 
 	/* Create a BIS for each bound connection */
-	hci_conn_hash_list_state(hdev, bis_list, ISO_LINK,
+	hci_conn_hash_list_state(hdev, bis_list, BIS_LINK,
 				 BT_BOUND, &data);
 
 	cp.handle = qos->bcast.big;
@@ -1835,12 +1841,12 @@ static bool hci_le_set_cig_params(struct hci_conn *conn, struct bt_iso_qos *qos)
 		for (data.cig = 0x00; data.cig < 0xf0; data.cig++) {
 			data.count = 0;
 
-			hci_conn_hash_list_state(hdev, find_cis, ISO_LINK,
+			hci_conn_hash_list_state(hdev, find_cis, CIS_LINK,
 						 BT_CONNECT, &data);
 			if (data.count)
 				continue;
 
-			hci_conn_hash_list_state(hdev, find_cis, ISO_LINK,
+			hci_conn_hash_list_state(hdev, find_cis, CIS_LINK,
 						 BT_CONNECTED, &data);
 			if (!data.count)
 				break;
@@ -1892,7 +1898,8 @@ struct hci_conn *hci_bind_cis(struct hci_dev *hdev, bdaddr_t *dst,
 	cis = hci_conn_hash_lookup_cis(hdev, dst, dst_type, qos->ucast.cig,
 				       qos->ucast.cis);
 	if (!cis) {
-		cis = hci_conn_add_unset(hdev, ISO_LINK, dst, HCI_ROLE_MASTER);
+		cis = hci_conn_add_unset(hdev, CIS_LINK, dst,
+					 HCI_ROLE_MASTER);
 		if (IS_ERR(cis))
 			return cis;
 		cis->cleanup = cis_cleanup;
@@ -1982,7 +1989,7 @@ bool hci_iso_setup_path(struct hci_conn *conn)
 
 int hci_conn_check_create_cis(struct hci_conn *conn)
 {
-	if (conn->type != ISO_LINK || !bacmp(&conn->dst, BDADDR_ANY))
+	if (conn->type != CIS_LINK)
 		return -EINVAL;
 
 	if (!conn->parent || conn->parent->state != BT_CONNECTED ||
@@ -2082,7 +2089,7 @@ struct hci_conn *hci_pa_create_sync(struct hci_dev *hdev, bdaddr_t *dst,
 
 	bt_dev_dbg(hdev, "dst %pMR type %d sid %d", dst, dst_type, sid);
 
-	conn = hci_conn_add_unset(hdev, ISO_LINK, dst, HCI_ROLE_SLAVE);
+	conn = hci_conn_add_unset(hdev, BIS_LINK, dst, HCI_ROLE_SLAVE);
 	if (IS_ERR(conn))
 		return conn;
 
@@ -2259,7 +2266,7 @@ struct hci_conn *hci_connect_bis(struct hci_dev *hdev, bdaddr_t *dst,
 	 * the start periodic advertising and create BIG commands have
 	 * been queued
 	 */
-	hci_conn_hash_list_state(hdev, bis_mark_per_adv, ISO_LINK,
+	hci_conn_hash_list_state(hdev, bis_mark_per_adv, BIS_LINK,
 				 BT_BOUND, &data);
 
 	/* Queue start periodic advertising and create BIG */
diff --git a/net/bluetooth/hci_core.c b/net/bluetooth/hci_core.c
index d53487bcd712c5..08c45343e932b6 100644
--- a/net/bluetooth/hci_core.c
+++ b/net/bluetooth/hci_core.c
@@ -2957,12 +2957,13 @@ int hci_recv_frame(struct hci_dev *hdev, struct sk_buff *skb)
 		break;
 	case HCI_ACLDATA_PKT:
 		/* Detect if ISO packet has been sent as ACL */
-		if (hci_conn_num(hdev, ISO_LINK)) {
+		if (hci_conn_num(hdev, CIS_LINK) ||
+		    hci_conn_num(hdev, BIS_LINK)) {
 			__u16 handle = __le16_to_cpu(hci_acl_hdr(skb)->handle);
 			__u8 type;
 
 			type = hci_conn_lookup_type(hdev, hci_handle(handle));
-			if (type == ISO_LINK)
+			if (type == CIS_LINK || type == BIS_LINK)
 				hci_skb_pkt_type(skb) = HCI_ISODATA_PKT;
 		}
 		break;
@@ -3397,7 +3398,8 @@ static inline void hci_quote_sent(struct hci_conn *conn, int num, int *quote)
 	case LE_LINK:
 		cnt = hdev->le_mtu ? hdev->le_cnt : hdev->acl_cnt;
 		break;
-	case ISO_LINK:
+	case CIS_LINK:
+	case BIS_LINK:
 		cnt = hdev->iso_mtu ? hdev->iso_cnt :
 			hdev->le_mtu ? hdev->le_cnt : hdev->acl_cnt;
 		break;
@@ -3411,7 +3413,7 @@ static inline void hci_quote_sent(struct hci_conn *conn, int num, int *quote)
 }
 
 static struct hci_conn *hci_low_sent(struct hci_dev *hdev, __u8 type,
-				     int *quote)
+				     __u8 type2, int *quote)
 {
 	struct hci_conn_hash *h = &hdev->conn_hash;
 	struct hci_conn *conn = NULL, *c;
@@ -3423,7 +3425,8 @@ static struct hci_conn *hci_low_sent(struct hci_dev *hdev, __u8 type,
 	rcu_read_lock();
 
 	list_for_each_entry_rcu(c, &h->list, list) {
-		if (c->type != type || skb_queue_empty(&c->data_q))
+		if ((c->type != type && c->type != type2) ||
+		    skb_queue_empty(&c->data_q))
 			continue;
 
 		if (c->state != BT_CONNECTED && c->state != BT_CONFIG)
@@ -3626,7 +3629,7 @@ static void hci_sched_sco(struct hci_dev *hdev, __u8 type)
 	else
 		cnt = &hdev->sco_cnt;
 
-	while (*cnt && (conn = hci_low_sent(hdev, type, &quote))) {
+	while (*cnt && (conn = hci_low_sent(hdev, type, type, &quote))) {
 		while (quote-- && (skb = skb_dequeue(&conn->data_q))) {
 			BT_DBG("skb %p len %d", skb, skb->len);
 			hci_send_frame(hdev, skb);
@@ -3754,12 +3757,14 @@ static void hci_sched_iso(struct hci_dev *hdev)
 
 	BT_DBG("%s", hdev->name);
 
-	if (!hci_conn_num(hdev, ISO_LINK))
+	if (!hci_conn_num(hdev, CIS_LINK) &&
+	    !hci_conn_num(hdev, BIS_LINK))
 		return;
 
 	cnt = hdev->iso_pkts ? &hdev->iso_cnt :
 		hdev->le_pkts ? &hdev->le_cnt : &hdev->acl_cnt;
-	while (*cnt && (conn = hci_low_sent(hdev, ISO_LINK, &quote))) {
+	while (*cnt && (conn = hci_low_sent(hdev, CIS_LINK, BIS_LINK,
+					    &quote))) {
 		while (quote-- && (skb = skb_dequeue(&conn->data_q))) {
 			BT_DBG("skb %p len %d", skb, skb->len);
 			hci_send_frame(hdev, skb);
diff --git a/net/bluetooth/hci_event.c b/net/bluetooth/hci_event.c
index 47ad62f10cef38..279b6435afc887 100644
--- a/net/bluetooth/hci_event.c
+++ b/net/bluetooth/hci_event.c
@@ -3778,7 +3778,7 @@ static void hci_unbound_cis_failed(struct hci_dev *hdev, u8 cig, u8 status)
 	lockdep_assert_held(&hdev->lock);
 
 	list_for_each_entry_safe(conn, tmp, &hdev->conn_hash.list, list) {
-		if (conn->type != ISO_LINK || !bacmp(&conn->dst, BDADDR_ANY) ||
+		if (conn->type != CIS_LINK ||
 		    conn->state == BT_OPEN || conn->iso_qos.ucast.cig != cig)
 			continue;
 
@@ -4455,7 +4455,8 @@ static void hci_num_comp_pkts_evt(struct hci_dev *hdev, void *data,
 
 			break;
 
-		case ISO_LINK:
+		case CIS_LINK:
+		case BIS_LINK:
 			if (hdev->iso_pkts) {
 				hdev->iso_cnt += count;
 				if (hdev->iso_cnt > hdev->iso_pkts)
@@ -6422,7 +6423,8 @@ static void hci_le_pa_sync_estabilished_evt(struct hci_dev *hdev, void *data,
 	conn->sync_handle = le16_to_cpu(ev->handle);
 	conn->sid = HCI_SID_INVALID;
 
-	mask |= hci_proto_connect_ind(hdev, &ev->bdaddr, ISO_LINK, &flags);
+	mask |= hci_proto_connect_ind(hdev, &ev->bdaddr, BIS_LINK,
+				      &flags);
 	if (!(mask & HCI_LM_ACCEPT)) {
 		hci_le_pa_term_sync(hdev, ev->handle);
 		goto unlock;
@@ -6432,7 +6434,7 @@ static void hci_le_pa_sync_estabilished_evt(struct hci_dev *hdev, void *data,
 		goto unlock;
 
 	/* Add connection to indicate PA sync event */
-	pa_sync = hci_conn_add_unset(hdev, ISO_LINK, BDADDR_ANY,
+	pa_sync = hci_conn_add_unset(hdev, BIS_LINK, BDADDR_ANY,
 				     HCI_ROLE_SLAVE);
 
 	if (IS_ERR(pa_sync))
@@ -6463,7 +6465,7 @@ static void hci_le_per_adv_report_evt(struct hci_dev *hdev, void *data,
 
 	hci_dev_lock(hdev);
 
-	mask |= hci_proto_connect_ind(hdev, BDADDR_ANY, ISO_LINK, &flags);
+	mask |= hci_proto_connect_ind(hdev, BDADDR_ANY, BIS_LINK, &flags);
 	if (!(mask & HCI_LM_ACCEPT))
 		goto unlock;
 
@@ -6754,7 +6756,7 @@ static void hci_le_cis_estabilished_evt(struct hci_dev *hdev, void *data,
 		goto unlock;
 	}
 
-	if (conn->type != ISO_LINK) {
+	if (conn->type != CIS_LINK) {
 		bt_dev_err(hdev,
 			   "Invalid connection link type handle 0x%4.4x",
 			   handle);
@@ -6872,7 +6874,7 @@ static void hci_le_cis_req_evt(struct hci_dev *hdev, void *data,
 	if (!acl)
 		goto unlock;
 
-	mask = hci_proto_connect_ind(hdev, &acl->dst, ISO_LINK, &flags);
+	mask = hci_proto_connect_ind(hdev, &acl->dst, CIS_LINK, &flags);
 	if (!(mask & HCI_LM_ACCEPT)) {
 		hci_le_reject_cis(hdev, ev->cis_handle);
 		goto unlock;
@@ -6880,8 +6882,8 @@ static void hci_le_cis_req_evt(struct hci_dev *hdev, void *data,
 
 	cis = hci_conn_hash_lookup_handle(hdev, cis_handle);
 	if (!cis) {
-		cis = hci_conn_add(hdev, ISO_LINK, &acl->dst, HCI_ROLE_SLAVE,
-				   cis_handle);
+		cis = hci_conn_add(hdev, CIS_LINK, &acl->dst,
+				   HCI_ROLE_SLAVE, cis_handle);
 		if (IS_ERR(cis)) {
 			hci_le_reject_cis(hdev, ev->cis_handle);
 			goto unlock;
@@ -7019,7 +7021,7 @@ static void hci_le_big_sync_established_evt(struct hci_dev *hdev, void *data,
 				bt_dev_dbg(hdev, "ignore too large handle %u", handle);
 				continue;
 			}
-			bis = hci_conn_add(hdev, ISO_LINK, BDADDR_ANY,
+			bis = hci_conn_add(hdev, BIS_LINK, BDADDR_ANY,
 					   HCI_ROLE_SLAVE, handle);
 			if (IS_ERR(bis))
 				continue;
@@ -7078,7 +7080,7 @@ static void hci_le_big_info_adv_report_evt(struct hci_dev *hdev, void *data,
 
 	hci_dev_lock(hdev);
 
-	mask |= hci_proto_connect_ind(hdev, BDADDR_ANY, ISO_LINK, &flags);
+	mask |= hci_proto_connect_ind(hdev, BDADDR_ANY, BIS_LINK, &flags);
 	if (!(mask & HCI_LM_ACCEPT))
 		goto unlock;
 
diff --git a/net/bluetooth/hci_sync.c b/net/bluetooth/hci_sync.c
index f6b70ed93c6210..f7bfc5d44b7741 100644
--- a/net/bluetooth/hci_sync.c
+++ b/net/bluetooth/hci_sync.c
@@ -2979,7 +2979,7 @@ static int hci_le_set_ext_scan_param_sync(struct hci_dev *hdev, u8 type,
 		if (sent) {
 			struct hci_conn *conn;
 
-			conn = hci_conn_hash_lookup_ba(hdev, ISO_LINK,
+			conn = hci_conn_hash_lookup_ba(hdev, BIS_LINK,
 						       &sent->bdaddr);
 			if (conn) {
 				struct bt_iso_qos *qos = &conn->iso_qos;
@@ -5596,7 +5596,7 @@ static int hci_connect_cancel_sync(struct hci_dev *hdev, struct hci_conn *conn,
 	if (conn->type == LE_LINK)
 		return hci_le_connect_cancel_sync(hdev, conn, reason);
 
-	if (conn->type == ISO_LINK) {
+	if (conn->type == CIS_LINK) {
 		/* BLUETOOTH CORE SPECIFICATION Version 5.3 | Vol 4, Part E
 		 * page 1857:
 		 *
@@ -5609,9 +5609,10 @@ static int hci_connect_cancel_sync(struct hci_dev *hdev, struct hci_conn *conn,
 			return hci_disconnect_sync(hdev, conn, reason);
 
 		/* CIS with no Create CIS sent have nothing to cancel */
-		if (bacmp(&conn->dst, BDADDR_ANY))
-			return HCI_ERROR_LOCAL_HOST_TERM;
+		return HCI_ERROR_LOCAL_HOST_TERM;
+	}
 
+	if (conn->type == BIS_LINK) {
 		/* There is no way to cancel a BIS without terminating the BIG
 		 * which is done later on connection cleanup.
 		 */
@@ -5673,9 +5674,12 @@ static int hci_reject_conn_sync(struct hci_dev *hdev, struct hci_conn *conn,
 {
 	struct hci_cp_reject_conn_req cp;
 
-	if (conn->type == ISO_LINK)
+	if (conn->type == CIS_LINK)
 		return hci_le_reject_cis_sync(hdev, conn, reason);
 
+	if (conn->type == BIS_LINK)
+		return -EINVAL;
+
 	if (conn->type == SCO_LINK || conn->type == ESCO_LINK)
 		return hci_reject_sco_sync(hdev, conn, reason);
 
@@ -7039,7 +7043,7 @@ static void create_pa_complete(struct hci_dev *hdev, void *data, int err)
 		goto unlock;
 
 	/* Add connection to indicate PA sync error */
-	pa_sync = hci_conn_add_unset(hdev, ISO_LINK, BDADDR_ANY,
+	pa_sync = hci_conn_add_unset(hdev, BIS_LINK, BDADDR_ANY,
 				     HCI_ROLE_SLAVE);
 
 	if (IS_ERR(pa_sync))
diff --git a/net/bluetooth/iso.c b/net/bluetooth/iso.c
index c0530442a94b9d..348cbb01aa9b3e 100644
--- a/net/bluetooth/iso.c
+++ b/net/bluetooth/iso.c
@@ -2200,7 +2200,7 @@ int iso_connect_ind(struct hci_dev *hdev, bdaddr_t *bdaddr, __u8 *flags)
 
 static void iso_connect_cfm(struct hci_conn *hcon, __u8 status)
 {
-	if (hcon->type != ISO_LINK) {
+	if (hcon->type != CIS_LINK && hcon->type != BIS_LINK) {
 		if (hcon->type != LE_LINK)
 			return;
 
@@ -2241,7 +2241,7 @@ static void iso_connect_cfm(struct hci_conn *hcon, __u8 status)
 
 static void iso_disconn_cfm(struct hci_conn *hcon, __u8 reason)
 {
-	if (hcon->type != ISO_LINK)
+	if (hcon->type != CIS_LINK && hcon->type != BIS_LINK)
 		return;
 
 	BT_DBG("hcon %p reason %d", hcon, reason);
diff --git a/net/bluetooth/mgmt.c b/net/bluetooth/mgmt.c
index f494eda5cc81c1..896a2970ba074d 100644
--- a/net/bluetooth/mgmt.c
+++ b/net/bluetooth/mgmt.c
@@ -3240,7 +3240,8 @@ static int disconnect(struct sock *sk, struct hci_dev *hdev, void *data,
 static u8 link_to_bdaddr(u8 link_type, u8 addr_type)
 {
 	switch (link_type) {
-	case ISO_LINK:
+	case CIS_LINK:
+	case BIS_LINK:
 	case LE_LINK:
 		switch (addr_type) {
 		case ADDR_LE_DEV_PUBLIC:
-- 
2.53.0

[PATCH 6.12.y 3/3] Bluetooth: hci_conn: Fix null ptr deref in hci_abort_conn()

[Sasha Levin]

From: Siwei Zhang <oss@fourdim.xyz>

[ Upstream commit 12917f591cea1af36087dba5b9ec888652f0b42a ]

hci_abort_conn() read hci_skb_event(hdev->sent_cmd) when a connection
was pending, but hdev->sent_cmd can be NULL while req_status is still
HCI_REQ_PEND, leading to a NULL pointer dereference and a general
protection fault from the hci_rx_work() receive path.

Instead of inspecting hdev->sent_cmd, track the in-flight create
connection command with a new per-connection HCI_CONN_CREATE flag and
route all cancellation through hci_cancel_connect_sync(), which
dispatches to a dedicated per-type cancel function. The create command
is in exactly one of two states: still queued, or in flight. The cancel
function holds cmd_sync_work_lock across the whole decision: the worker
takes this lock to dequeue every entry, so while it is held a queued
command cannot start running and an in-flight command cannot complete
and let the next command become pending. This keeps the flag test and
hci_cmd_sync_cancel() atomic with respect to the worker, so a queued
command is simply dequeued, and an in-flight command owned by this
connection is cancelled without the risk of cancelling an unrelated
command that became pending in the meantime. CIS uses the same flag
mechanism via HCI_CONN_CREATE_CIS but cannot be dequeued per-connection.

hci_acl_create_conn_sync() and hci_le_create_conn_sync() clear
HCI_CONN_CREATE after the create command completes, but the command
status handler can free conn via hci_conn_del() (for example when the
controller rejects the connection) while the worker is still blocked on
the connection complete event. Hold a reference on conn across the
create command so the flag can be cleared without a use-after-free.

Fixes: a13f316e90fd ("Bluetooth: hci_conn: Consolidate code for aborting connections")
Cc: stable@vger.kernel.org
Suggested-by: XIAO WU <xiaowu.417@qq.com>
Assisted-by: Claude:claude-opus-4-8
Signed-off-by: Siwei Zhang <oss@fourdim.xyz>
Signed-off-by: Luiz Augusto von Dentz <luiz.von.dentz@intel.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
 include/net/bluetooth/hci_core.h |   1 +
 net/bluetooth/hci_conn.c         |  21 +----
 net/bluetooth/hci_sync.c         | 133 +++++++++++++++++++++++++++----
 3 files changed, 123 insertions(+), 32 deletions(-)

diff --git a/include/net/bluetooth/hci_core.h b/include/net/bluetooth/hci_core.h
index ab2cf7489ce783..44da2e383aaa8d 100644
--- a/include/net/bluetooth/hci_core.h
+++ b/include/net/bluetooth/hci_core.h
@@ -958,6 +958,7 @@ enum {
 	HCI_CONN_AUTH_FAILURE,
 	HCI_CONN_PER_ADV,
 	HCI_CONN_BIG_CREATED,
+	HCI_CONN_CREATE,
 	HCI_CONN_CREATE_CIS,
 	HCI_CONN_CREATE_BIG_SYNC,
 	HCI_CONN_BIG_SYNC,
diff --git a/net/bluetooth/hci_conn.c b/net/bluetooth/hci_conn.c
index 2e7a2e60d8133d..17b0cd1c2b5241 100644
--- a/net/bluetooth/hci_conn.c
+++ b/net/bluetooth/hci_conn.c
@@ -2921,26 +2921,11 @@ int hci_abort_conn(struct hci_conn *conn, u8 reason)
 
 	conn->abort_reason = reason;
 
-	/* If the connection is pending check the command opcode since that
-	 * might be blocking on hci_cmd_sync_work while waiting its respective
-	 * event so we need to hci_cmd_sync_cancel to cancel it.
-	 *
-	 * hci_connect_le serializes the connection attempts so only one
-	 * connection can be in BT_CONNECT at time.
+	/* Cancel the connect attempt. A return of 0 means the create command
+	 * was still queued and got dequeued, so there is nothing to disconnect.
 	 */
-	if (conn->state == BT_CONNECT && READ_ONCE(hdev->req_status) == HCI_REQ_PEND) {
-		switch (hci_skb_event(hdev->sent_cmd)) {
-		case HCI_EV_CONN_COMPLETE:
-		case HCI_EV_LE_CONN_COMPLETE:
-		case HCI_EV_LE_ENHANCED_CONN_COMPLETE:
-		case HCI_EVT_LE_CIS_ESTABLISHED:
-			hci_cmd_sync_cancel(hdev, ECANCELED);
-			break;
-		}
-	/* Cancel connect attempt if still queued/pending */
-	} else if (!hci_cancel_connect_sync(hdev, conn)) {
+	if (!hci_cancel_connect_sync(hdev, conn))
 		return 0;
-	}
 
 	/* Run immediately if on cmd_sync_work since this may be called
 	 * as a result to MGMT_OP_DISCONNECT/MGMT_OP_UNPAIR which does
diff --git a/net/bluetooth/hci_sync.c b/net/bluetooth/hci_sync.c
index f7bfc5d44b7741..29ba5b2e91aa9f 100644
--- a/net/bluetooth/hci_sync.c
+++ b/net/bluetooth/hci_sync.c
@@ -6568,6 +6568,11 @@ static int hci_le_create_conn_sync(struct hci_dev *hdev, void *data)
 
 	bt_dev_dbg(hdev, "conn %p", conn);
 
+	/* Hold a reference so conn stays valid for the HCI_CONN_CREATE
+	 * clear_bit() at done.
+	 */
+	hci_conn_get(conn);
+
 	clear_bit(HCI_CONN_SCANNING, &conn->flags);
 	conn->state = BT_CONNECT;
 
@@ -6580,6 +6585,7 @@ static int hci_le_create_conn_sync(struct hci_dev *hdev, void *data)
 		    hdev->le_scan_type == LE_SCAN_ACTIVE &&
 		    !hci_dev_test_flag(hdev, HCI_LE_SIMULTANEOUS_ROLES)) {
 			hci_conn_del(conn);
+			hci_conn_put(conn);
 			return -EBUSY;
 		}
 
@@ -6625,6 +6631,12 @@ static int hci_le_create_conn_sync(struct hci_dev *hdev, void *data)
 					     &own_addr_type);
 	if (err)
 		goto done;
+
+	/* Mark create connection in flight so hci_cancel_connect_sync() can
+	 * cancel it while blocking on the connection complete event.
+	 */
+	set_bit(HCI_CONN_CREATE, &conn->flags);
+
 	/* Send command LE Extended Create Connection if supported */
 	if (use_ext_conn(hdev)) {
 		err = hci_le_ext_create_conn_sync(hdev, conn, own_addr_type);
@@ -6660,11 +6672,14 @@ static int hci_le_create_conn_sync(struct hci_dev *hdev, void *data)
 				       conn->conn_timeout, NULL);
 
 done:
+	clear_bit(HCI_CONN_CREATE, &conn->flags);
+
 	if (err == -ETIMEDOUT)
 		hci_le_connect_cancel_sync(hdev, conn, 0x00);
 
 	/* Re-enable advertising after the connection attempt is finished. */
 	hci_resume_advertising_sync(hdev);
+	hci_conn_put(conn);
 	return err;
 }
 
@@ -6939,10 +6954,25 @@ static int hci_acl_create_conn_sync(struct hci_dev *hdev, void *data)
 	else
 		cp.role_switch = 0x00;
 
-	return __hci_cmd_sync_status_sk(hdev, HCI_OP_CREATE_CONN,
-					sizeof(cp), &cp,
-					HCI_EV_CONN_COMPLETE,
-					conn->conn_timeout, NULL);
+	/* Hold a reference so conn stays valid for the HCI_CONN_CREATE
+	 * clear_bit() below.
+	 */
+	hci_conn_get(conn);
+
+	/* Mark create connection in flight so hci_cancel_connect_sync() can
+	 * cancel it while blocking on the connection complete event.
+	 */
+	set_bit(HCI_CONN_CREATE, &conn->flags);
+
+	err = __hci_cmd_sync_status_sk(hdev, HCI_OP_CREATE_CONN,
+				       sizeof(cp), &cp,
+				       HCI_EV_CONN_COMPLETE,
+				       conn->conn_timeout, NULL);
+
+	clear_bit(HCI_CONN_CREATE, &conn->flags);
+	hci_conn_put(conn);
+
+	return err;
 }
 
 int hci_connect_acl_sync(struct hci_dev *hdev, struct hci_conn *conn)
@@ -6988,22 +7018,97 @@ int hci_connect_le_sync(struct hci_dev *hdev, struct hci_conn *conn)
 				       create_le_conn_complete);
 }
 
-int hci_cancel_connect_sync(struct hci_dev *hdev, struct hci_conn *conn)
+static int hci_acl_cancel_create_conn_sync(struct hci_dev *hdev,
+					   struct hci_conn *conn)
 {
-	if (conn->state != BT_OPEN)
-		return -EINVAL;
+	struct hci_cmd_sync_work_entry *entry;
+	int err = -EBUSY;
+
+	/* cmd_sync_work_lock makes the HCI_CONN_CREATE test and the cancel
+	 * atomic against the worker, which takes this lock to dequeue every
+	 * entry: while it is held no other command can become pending, so
+	 * hci_cmd_sync_cancel() cannot cancel an unrelated command.
+	 */
+	mutex_lock(&hdev->cmd_sync_work_lock);
+
+	/* In flight: this connection owns the pending request, cancel it. */
+	if (test_bit(HCI_CONN_CREATE, &conn->flags)) {
+		hci_cmd_sync_cancel(hdev, ECANCELED);
+		goto unlock;
+	}
+
+	/* Still queued: a successful dequeue means it never started, so there
+	 * is nothing to disconnect.
+	 */
+	entry = _hci_cmd_sync_lookup_entry(hdev, hci_acl_create_conn_sync, conn,
+					   NULL);
+	if (entry) {
+		_hci_cmd_sync_cancel_entry(hdev, entry, -ECANCELED);
+		err = 0;
+	}
+
+unlock:
+	mutex_unlock(&hdev->cmd_sync_work_lock);
+	return err;
+}
+
+static int hci_le_cancel_create_conn_sync(struct hci_dev *hdev,
+					  struct hci_conn *conn)
+{
+	struct hci_cmd_sync_work_entry *entry;
+	int err = -EBUSY;
 
+	/* cmd_sync_work_lock keeps the HCI_CONN_CREATE test and the cancel
+	 * atomic against the cmd_sync worker.
+	 */
+	mutex_lock(&hdev->cmd_sync_work_lock);
+
+	if (test_bit(HCI_CONN_CREATE, &conn->flags)) {
+		hci_cmd_sync_cancel(hdev, ECANCELED);
+		goto unlock;
+	}
+
+	entry = _hci_cmd_sync_lookup_entry(hdev, hci_le_create_conn_sync, conn,
+					   create_le_conn_complete);
+	if (entry) {
+		_hci_cmd_sync_cancel_entry(hdev, entry, -ECANCELED);
+		err = 0;
+	}
+
+unlock:
+	mutex_unlock(&hdev->cmd_sync_work_lock);
+	return err;
+}
+
+static int hci_cis_cancel_create_conn_sync(struct hci_dev *hdev,
+					   struct hci_conn *conn)
+{
+	/* LE Create CIS is shared by the whole CIG and cannot be dequeued
+	 * per-connection, so only an in-flight command can be cancelled.
+	 * cmd_sync_work_lock keeps the test and the cancel atomic against the
+	 * cmd_sync worker.
+	 */
+	mutex_lock(&hdev->cmd_sync_work_lock);
+
+	if (test_bit(HCI_CONN_CREATE_CIS, &conn->flags))
+		hci_cmd_sync_cancel(hdev, ECANCELED);
+
+	mutex_unlock(&hdev->cmd_sync_work_lock);
+	return -EBUSY;
+}
+
+int hci_cancel_connect_sync(struct hci_dev *hdev, struct hci_conn *conn)
+{
 	switch (conn->type) {
 	case ACL_LINK:
-		return !hci_cmd_sync_dequeue_once(hdev,
-						  hci_acl_create_conn_sync,
-						  conn, NULL);
+		return hci_acl_cancel_create_conn_sync(hdev, conn);
 	case LE_LINK:
-		return !hci_cmd_sync_dequeue_once(hdev, hci_le_create_conn_sync,
-						  conn, create_le_conn_complete);
+		return hci_le_cancel_create_conn_sync(hdev, conn);
+	case CIS_LINK:
+		return hci_cis_cancel_create_conn_sync(hdev, conn);
+	default:
+		return -ENOENT;
 	}
-
-	return -ENOENT;
 }
 
 int hci_le_conn_update_sync(struct hci_dev *hdev, struct hci_conn *conn,
-- 
2.53.0