2021-12-03 07:16:25

by Manish Mandlik

[permalink] [raw]
Subject: [PATCH v7 1/2] bluetooth: Handle MSFT Monitor Device Event

Whenever the controller starts/stops monitoring a bt device, it sends
MSFT Monitor Device event. Add handler to read this vendor event.

Test performed:
- Verified by logs that the MSFT Monitor Device event is received from
the controller whenever it starts/stops monitoring a device.

Signed-off-by: Manish Mandlik <[email protected]>
Reviewed-by: Miao-chen Chou <[email protected]>

---

Hello Bt-Maintainers,

As mentioned in the bluez patch series [1], we need to capture the 'MSFT
Monitor Device' event from the controller and pass on the necessary
information to the bluetoothd.

This is required to further optimize the power consumption by avoiding
handling of RSSI thresholds and timeouts in the user space and let the
controller do the RSSI tracking.

This patch series adds support to read the MSFT vendor event
HCI_VS_MSFT_LE_Monitor_Device_Event and introduces new MGMT events
MGMT_EV_ADV_MONITOR_DEVICE_FOUND and MGMT_EV_ADV_MONITOR_DEVICE_LOST to
indicate that the controller has started/stopped tracking a particular
device.

Please let me know what you think about this or if you have any further
questions.

[1] https://patchwork.kernel.org/project/bluetooth/list/?series=583423

Thanks,
Manish.

(no changes since v6)

Changes in v6:
- Fix compiler warning bt_dev_err() missing argument.

Changes in v5:
- Split v4 into two patches.
- Buffer controller Device Found event and maintain the device tracking
state in the kernel.

Changes in v4:
- Add Advertisement Monitor Device Found event and update addr type.

Changes in v3:
- Discard changes to the Device Found event and notify bluetoothd only
when the controller stops monitoring the device via new Device Lost
event.

Changes in v2:
- Instead of creating a new 'Device Tracking' event, add a flag 'Device
Tracked' in the existing 'Device Found' event and add a new 'Device
Lost' event to indicate that the controller has stopped tracking that
device.

include/net/bluetooth/hci_core.h | 11 +++
net/bluetooth/hci_core.c | 1 +
net/bluetooth/msft.c | 127 ++++++++++++++++++++++++++++++-
3 files changed, 138 insertions(+), 1 deletion(-)

diff --git a/include/net/bluetooth/hci_core.h b/include/net/bluetooth/hci_core.h
index 7bae8376fd6f..5ccd19dec77c 100644
--- a/include/net/bluetooth/hci_core.h
+++ b/include/net/bluetooth/hci_core.h
@@ -258,6 +258,15 @@ struct adv_info {

#define HCI_ADV_TX_POWER_NO_PREFERENCE 0x7F

+struct monitored_device {
+ struct list_head list;
+
+ bdaddr_t bdaddr;
+ __u8 addr_type;
+ __u16 handle;
+ bool notified;
+};
+
struct adv_pattern {
struct list_head list;
__u8 ad_type;
@@ -589,6 +598,8 @@ struct hci_dev {

struct delayed_work interleave_scan;

+ struct list_head monitored_devices;
+
#if IS_ENABLED(CONFIG_BT_LEDS)
struct led_trigger *power_led;
#endif
diff --git a/net/bluetooth/hci_core.c b/net/bluetooth/hci_core.c
index fdc0dcf8ee36..d4bcd511530a 100644
--- a/net/bluetooth/hci_core.c
+++ b/net/bluetooth/hci_core.c
@@ -2503,6 +2503,7 @@ struct hci_dev *hci_alloc_dev_priv(int sizeof_priv)
INIT_LIST_HEAD(&hdev->conn_hash.list);
INIT_LIST_HEAD(&hdev->adv_instances);
INIT_LIST_HEAD(&hdev->blocked_keys);
+ INIT_LIST_HEAD(&hdev->monitored_devices);

INIT_LIST_HEAD(&hdev->local_codecs);
INIT_WORK(&hdev->rx_work, hci_rx_work);
diff --git a/net/bluetooth/msft.c b/net/bluetooth/msft.c
index 1122097e1e49..aadabe78baf6 100644
--- a/net/bluetooth/msft.c
+++ b/net/bluetooth/msft.c
@@ -80,6 +80,14 @@ struct msft_rp_le_set_advertisement_filter_enable {
__u8 sub_opcode;
} __packed;

+#define MSFT_EV_LE_MONITOR_DEVICE 0x02
+struct msft_ev_le_monitor_device {
+ __u8 addr_type;
+ bdaddr_t bdaddr;
+ __u8 monitor_handle;
+ __u8 monitor_state;
+} __packed;
+
struct msft_monitor_advertisement_handle_data {
__u8 msft_handle;
__u16 mgmt_handle;
@@ -266,6 +274,7 @@ static void msft_le_cancel_monitor_advertisement_cb(struct hci_dev *hdev,
struct msft_data *msft = hdev->msft_data;
int err;
bool pending;
+ struct monitored_device *dev, *tmp;

if (status)
goto done;
@@ -296,6 +305,15 @@ static void msft_le_cancel_monitor_advertisement_cb(struct hci_dev *hdev,

list_del(&handle_data->list);
kfree(handle_data);
+
+ /* Clear any monitored devices by this Adv Monitor */
+ list_for_each_entry_safe(dev, tmp, &hdev->monitored_devices,
+ list) {
+ if (dev->handle == handle_data->mgmt_handle) {
+ list_del(&dev->list);
+ kfree(dev);
+ }
+ }
}

/* If remove all monitors is required, we need to continue the process
@@ -538,6 +556,7 @@ void msft_do_close(struct hci_dev *hdev)
struct msft_data *msft = hdev->msft_data;
struct msft_monitor_advertisement_handle_data *handle_data, *tmp;
struct adv_monitor *monitor;
+ struct monitored_device *dev, *tmp_dev;

if (!msft)
return;
@@ -557,6 +576,16 @@ void msft_do_close(struct hci_dev *hdev)
list_del(&handle_data->list);
kfree(handle_data);
}
+
+ hci_dev_lock(hdev);
+
+ /* Clear any devices that are being monitored */
+ list_for_each_entry_safe(dev, tmp_dev, &hdev->monitored_devices, list) {
+ list_del(&dev->list);
+ kfree(dev);
+ }
+
+ hci_dev_unlock(hdev);
}

void msft_register(struct hci_dev *hdev)
@@ -590,6 +619,90 @@ void msft_unregister(struct hci_dev *hdev)
kfree(msft);
}

+/* This function requires the caller holds hdev->lock */
+static void msft_device_found(struct hci_dev *hdev, bdaddr_t *bdaddr,
+ __u8 addr_type, __u16 mgmt_handle)
+{
+ struct monitored_device *dev;
+
+ dev = kmalloc(sizeof(*dev), GFP_KERNEL);
+ if (!dev) {
+ bt_dev_err(hdev, "MSFT vendor event %u: no memory",
+ MSFT_EV_LE_MONITOR_DEVICE);
+ return;
+ }
+
+ bacpy(&dev->bdaddr, bdaddr);
+ dev->addr_type = addr_type;
+ dev->handle = mgmt_handle;
+ dev->notified = false;
+
+ INIT_LIST_HEAD(&dev->list);
+ list_add(&dev->list, &hdev->monitored_devices);
+}
+
+/* This function requires the caller holds hdev->lock */
+static void msft_device_lost(struct hci_dev *hdev, bdaddr_t *bdaddr,
+ __u8 addr_type, __u16 mgmt_handle)
+{
+ struct monitored_device *dev, *tmp;
+
+ list_for_each_entry_safe(dev, tmp, &hdev->monitored_devices, list) {
+ if (dev->handle == mgmt_handle) {
+ list_del(&dev->list);
+ kfree(dev);
+
+ break;
+ }
+ }
+}
+
+/* This function requires the caller holds hdev->lock */
+static void msft_monitor_device_evt(struct hci_dev *hdev, struct sk_buff *skb)
+{
+ struct msft_ev_le_monitor_device *ev = (void *)skb->data;
+ struct msft_monitor_advertisement_handle_data *handle_data;
+ u8 addr_type;
+
+ if (skb->len < sizeof(*ev)) {
+ bt_dev_err(hdev,
+ "MSFT vendor event %u: insufficient data (len: %u)",
+ MSFT_EV_LE_MONITOR_DEVICE, skb->len);
+ return;
+ }
+ skb_pull(skb, sizeof(*ev));
+
+ bt_dev_dbg(hdev,
+ "MSFT vendor event %u: handle 0x%04x state %d addr %pMR",
+ MSFT_EV_LE_MONITOR_DEVICE, ev->monitor_handle,
+ ev->monitor_state, &ev->bdaddr);
+
+ handle_data = msft_find_handle_data(hdev, ev->monitor_handle, false);
+
+ switch (ev->addr_type) {
+ case ADDR_LE_DEV_PUBLIC:
+ addr_type = BDADDR_LE_PUBLIC;
+ break;
+
+ case ADDR_LE_DEV_RANDOM:
+ addr_type = BDADDR_LE_RANDOM;
+ break;
+
+ default:
+ bt_dev_err(hdev,
+ "MSFT vendor event %u: unknown addr type 0x%02x",
+ MSFT_EV_LE_MONITOR_DEVICE, ev->addr_type);
+ return;
+ }
+
+ if (ev->monitor_state)
+ msft_device_found(hdev, &ev->bdaddr, addr_type,
+ handle_data->mgmt_handle);
+ else
+ msft_device_lost(hdev, &ev->bdaddr, addr_type,
+ handle_data->mgmt_handle);
+}
+
void msft_vendor_evt(struct hci_dev *hdev, struct sk_buff *skb)
{
struct msft_data *msft = hdev->msft_data;
@@ -617,10 +730,22 @@ void msft_vendor_evt(struct hci_dev *hdev, struct sk_buff *skb)
if (skb->len < 1)
return;

+ hci_dev_lock(hdev);
+
event = *skb->data;
skb_pull(skb, 1);

- bt_dev_dbg(hdev, "MSFT vendor event %u", event);
+ switch (event) {
+ case MSFT_EV_LE_MONITOR_DEVICE:
+ msft_monitor_device_evt(hdev, skb);
+ break;
+
+ default:
+ bt_dev_dbg(hdev, "MSFT vendor event %u", event);
+ break;
+ }
+
+ hci_dev_unlock(hdev);
}

__u64 msft_get_features(struct hci_dev *hdev)
--
2.34.0.384.gca35af8252-goog



2021-12-03 07:16:30

by Manish Mandlik

[permalink] [raw]
Subject: [PATCH v7 2/2] bluetooth: Add MGMT Adv Monitor Device Found/Lost events

This patch introduces two new MGMT events for notifying the bluetoothd
whenever the controller starts/stops monitoring a device.

Test performed:
- Verified by logs that the MSFT Monitor Device is received from the
controller and the bluetoothd is notified whenever the controller
starts/stops monitoring a device.

Signed-off-by: Manish Mandlik <[email protected]>
Reviewed-by: Miao-chen Chou <[email protected]>

---

Changes in v7:
- Refactor mgmt_device_found() to fix stack frame size limit

Changes in v6:
- Fix compiler warning for mgmt_adv_monitor_device_found().

Changes in v5:
- New patch in the series. Split previous patch into two.
- Update the Device Found logic to send existing Device Found event or
Adv Monitor Device Found event depending on the active scanning state.

include/net/bluetooth/hci_core.h | 3 +
include/net/bluetooth/mgmt.h | 16 +++++
net/bluetooth/mgmt.c | 106 +++++++++++++++++++++++++++++--
net/bluetooth/msft.c | 15 ++++-
4 files changed, 134 insertions(+), 6 deletions(-)

diff --git a/include/net/bluetooth/hci_core.h b/include/net/bluetooth/hci_core.h
index 5ccd19dec77c..3b53214ff49f 100644
--- a/include/net/bluetooth/hci_core.h
+++ b/include/net/bluetooth/hci_core.h
@@ -599,6 +599,7 @@ struct hci_dev {
struct delayed_work interleave_scan;

struct list_head monitored_devices;
+ bool advmon_pend_notify;

#if IS_ENABLED(CONFIG_BT_LEDS)
struct led_trigger *power_led;
@@ -1847,6 +1848,8 @@ void mgmt_adv_monitor_removed(struct hci_dev *hdev, u16 handle);
int mgmt_phy_configuration_changed(struct hci_dev *hdev, struct sock *skip);
int mgmt_add_adv_patterns_monitor_complete(struct hci_dev *hdev, u8 status);
int mgmt_remove_adv_monitor_complete(struct hci_dev *hdev, u8 status);
+void mgmt_adv_monitor_device_lost(struct hci_dev *hdev, u16 handle,
+ bdaddr_t *bdaddr, u8 addr_type);

u8 hci_le_conn_update(struct hci_conn *conn, u16 min, u16 max, u16 latency,
u16 to_multiplier);
diff --git a/include/net/bluetooth/mgmt.h b/include/net/bluetooth/mgmt.h
index 107b25deae68..99266f7aebdc 100644
--- a/include/net/bluetooth/mgmt.h
+++ b/include/net/bluetooth/mgmt.h
@@ -1104,3 +1104,19 @@ struct mgmt_ev_controller_resume {
#define MGMT_WAKE_REASON_NON_BT_WAKE 0x0
#define MGMT_WAKE_REASON_UNEXPECTED 0x1
#define MGMT_WAKE_REASON_REMOTE_WAKE 0x2
+
+#define MGMT_EV_ADV_MONITOR_DEVICE_FOUND 0x002f
+struct mgmt_ev_adv_monitor_device_found {
+ __le16 monitor_handle;
+ struct mgmt_addr_info addr;
+ __s8 rssi;
+ __le32 flags;
+ __le16 eir_len;
+ __u8 eir[0];
+} __packed;
+
+#define MGMT_EV_ADV_MONITOR_DEVICE_LOST 0x0030
+struct mgmt_ev_adv_monitor_device_lost {
+ __le16 monitor_handle;
+ struct mgmt_addr_info addr;
+} __packed;
diff --git a/net/bluetooth/mgmt.c b/net/bluetooth/mgmt.c
index bf989ae03f9f..06e0769f350d 100644
--- a/net/bluetooth/mgmt.c
+++ b/net/bluetooth/mgmt.c
@@ -174,6 +174,8 @@ static const u16 mgmt_events[] = {
MGMT_EV_ADV_MONITOR_REMOVED,
MGMT_EV_CONTROLLER_SUSPEND,
MGMT_EV_CONTROLLER_RESUME,
+ MGMT_EV_ADV_MONITOR_DEVICE_FOUND,
+ MGMT_EV_ADV_MONITOR_DEVICE_LOST,
};

static const u16 mgmt_untrusted_commands[] = {
@@ -9524,6 +9526,100 @@ static bool is_filter_match(struct hci_dev *hdev, s8 rssi, u8 *eir,
return true;
}

+void mgmt_adv_monitor_device_lost(struct hci_dev *hdev, u16 handle,
+ bdaddr_t *bdaddr, u8 addr_type)
+{
+ struct mgmt_ev_adv_monitor_device_lost ev;
+
+ ev.monitor_handle = cpu_to_le16(handle);
+ bacpy(&ev.addr.bdaddr, bdaddr);
+ ev.addr.type = addr_type;
+
+ mgmt_event(MGMT_EV_ADV_MONITOR_DEVICE_LOST, hdev, &ev, sizeof(ev),
+ NULL);
+}
+
+static void mgmt_adv_monitor_device_found(struct hci_dev *hdev,
+ struct mgmt_ev_device_found *ev,
+ size_t ev_size, bool discovering)
+{
+ char buf[518];
+ struct mgmt_ev_adv_monitor_device_found *advmon_ev = (void *)buf;
+ size_t advmon_ev_size;
+ struct monitored_device *dev, *tmp;
+ bool matched = false;
+ bool notified = false;
+
+ /* We have received the Advertisement Report because:
+ * 1. the kernel has initiated active discovery
+ * 2. if not, we have pend_le_reports > 0 in which case we are doing
+ * passive scanning
+ * 3. if none of the above is true, we have one or more active
+ * Advertisement Monitor
+ *
+ * For case 1 and 2, report all advertisements via MGMT_EV_DEVICE_FOUND
+ * and report ONLY one advertisement per device for the matched Monitor
+ * via MGMT_EV_ADV_MONITOR_DEVICE_FOUND event.
+ *
+ * For case 3, since we are not active scanning and all advertisements
+ * received are due to a matched Advertisement Monitor, report all
+ * advertisements ONLY via MGMT_EV_ADV_MONITOR_DEVICE_FOUND event.
+ */
+ if (discovering) {
+ mgmt_event(MGMT_EV_DEVICE_FOUND, hdev, ev, ev_size, NULL);
+
+ if (!hdev->advmon_pend_notify)
+ return;
+ }
+
+ /* Make sure that the buffer is big enough */
+ advmon_ev_size = ev_size + (sizeof(*advmon_ev) - sizeof(*ev));
+ if (advmon_ev_size > sizeof(buf))
+ return;
+
+ /* ADV_MONITOR_DEVICE_FOUND is similar to DEVICE_FOUND event except
+ * that it also has 'monitor_handle'. Make a copy of DEVICE_FOUND and
+ * store monitor_handle of the matched monitor.
+ */
+ memcpy(&advmon_ev->addr, ev, ev_size);
+
+ hdev->advmon_pend_notify = false;
+
+ list_for_each_entry_safe(dev, tmp, &hdev->monitored_devices, list) {
+ if (!bacmp(&dev->bdaddr, &advmon_ev->addr.bdaddr)) {
+ matched = true;
+
+ if (!dev->notified) {
+ advmon_ev->monitor_handle =
+ cpu_to_le16(dev->handle);
+
+ mgmt_event(MGMT_EV_ADV_MONITOR_DEVICE_FOUND,
+ hdev, advmon_ev, advmon_ev_size,
+ NULL);
+
+ notified = true;
+ dev->notified = true;
+ }
+ }
+
+ if (!dev->notified)
+ hdev->advmon_pend_notify = true;
+ }
+
+ if (!discovering &&
+ ((matched && !notified) || !msft_monitor_supported(hdev))) {
+ /* Handle 0 indicates that we are not active scanning and this
+ * is a subsequent advertisement report for an already matched
+ * Advertisement Monitor or the controller offloading support
+ * is not available.
+ */
+ advmon_ev->monitor_handle = 0;
+
+ mgmt_event(MGMT_EV_ADV_MONITOR_DEVICE_FOUND, hdev, advmon_ev,
+ advmon_ev_size, NULL);
+ }
+}
+
void mgmt_device_found(struct hci_dev *hdev, bdaddr_t *bdaddr, u8 link_type,
u8 addr_type, u8 *dev_class, s8 rssi, u32 flags,
u8 *eir, u16 eir_len, u8 *scan_rsp, u8 scan_rsp_len)
@@ -9531,6 +9627,7 @@ void mgmt_device_found(struct hci_dev *hdev, bdaddr_t *bdaddr, u8 link_type,
char buf[512];
struct mgmt_ev_device_found *ev = (void *)buf;
size_t ev_size;
+ bool report_device_found = hci_discovery_active(hdev);

/* Don't send events for a non-kernel initiated discovery. With
* LE one exception is if we have pend_le_reports > 0 in which
@@ -9539,11 +9636,10 @@ void mgmt_device_found(struct hci_dev *hdev, bdaddr_t *bdaddr, u8 link_type,
if (!hci_discovery_active(hdev)) {
if (link_type == ACL_LINK)
return;
- if (link_type == LE_LINK &&
- list_empty(&hdev->pend_le_reports) &&
- !hci_is_adv_monitoring(hdev)) {
+ if (link_type == LE_LINK && !list_empty(&hdev->pend_le_reports))
+ report_device_found = true;
+ else if (!hci_is_adv_monitoring(hdev))
return;
- }
}

if (hdev->discovery.result_filtering) {
@@ -9606,7 +9702,7 @@ void mgmt_device_found(struct hci_dev *hdev, bdaddr_t *bdaddr, u8 link_type,
ev->eir_len = cpu_to_le16(eir_len + scan_rsp_len);
ev_size = sizeof(*ev) + eir_len + scan_rsp_len;

- mgmt_event(MGMT_EV_DEVICE_FOUND, hdev, ev, ev_size, NULL);
+ mgmt_adv_monitor_device_found(hdev, ev, ev_size, report_device_found);
}

void mgmt_remote_name(struct hci_dev *hdev, bdaddr_t *bdaddr, u8 link_type,
diff --git a/net/bluetooth/msft.c b/net/bluetooth/msft.c
index aadabe78baf6..3e2385562d2b 100644
--- a/net/bluetooth/msft.c
+++ b/net/bluetooth/msft.c
@@ -579,8 +579,16 @@ void msft_do_close(struct hci_dev *hdev)

hci_dev_lock(hdev);

- /* Clear any devices that are being monitored */
+ /* Clear any devices that are being monitored and notify device lost */
+
+ hdev->advmon_pend_notify = false;
+
list_for_each_entry_safe(dev, tmp_dev, &hdev->monitored_devices, list) {
+ if (dev->notified)
+ mgmt_adv_monitor_device_lost(hdev, dev->handle,
+ &dev->bdaddr,
+ dev->addr_type);
+
list_del(&dev->list);
kfree(dev);
}
@@ -639,6 +647,7 @@ static void msft_device_found(struct hci_dev *hdev, bdaddr_t *bdaddr,

INIT_LIST_HEAD(&dev->list);
list_add(&dev->list, &hdev->monitored_devices);
+ hdev->advmon_pend_notify = true;
}

/* This function requires the caller holds hdev->lock */
@@ -649,6 +658,10 @@ static void msft_device_lost(struct hci_dev *hdev, bdaddr_t *bdaddr,

list_for_each_entry_safe(dev, tmp, &hdev->monitored_devices, list) {
if (dev->handle == mgmt_handle) {
+ if (dev->notified)
+ mgmt_adv_monitor_device_lost(hdev, mgmt_handle,
+ bdaddr, addr_type);
+
list_del(&dev->list);
kfree(dev);

--
2.34.0.384.gca35af8252-goog


2021-12-03 22:13:21

by Luiz Augusto von Dentz

[permalink] [raw]
Subject: Re: [PATCH v7 1/2] bluetooth: Handle MSFT Monitor Device Event

Hi Manish,

On Thu, Dec 2, 2021 at 11:16 PM Manish Mandlik <[email protected]> wrote:
>
> Whenever the controller starts/stops monitoring a bt device, it sends
> MSFT Monitor Device event. Add handler to read this vendor event.
>
> Test performed:
> - Verified by logs that the MSFT Monitor Device event is received from
> the controller whenever it starts/stops monitoring a device.
>
> Signed-off-by: Manish Mandlik <[email protected]>
> Reviewed-by: Miao-chen Chou <[email protected]>
>
> ---
>
> Hello Bt-Maintainers,
>
> As mentioned in the bluez patch series [1], we need to capture the 'MSFT
> Monitor Device' event from the controller and pass on the necessary
> information to the bluetoothd.
>
> This is required to further optimize the power consumption by avoiding
> handling of RSSI thresholds and timeouts in the user space and let the
> controller do the RSSI tracking.
>
> This patch series adds support to read the MSFT vendor event
> HCI_VS_MSFT_LE_Monitor_Device_Event and introduces new MGMT events
> MGMT_EV_ADV_MONITOR_DEVICE_FOUND and MGMT_EV_ADV_MONITOR_DEVICE_LOST to
> indicate that the controller has started/stopped tracking a particular
> device.
>
> Please let me know what you think about this or if you have any further
> questions.
>
> [1] https://patchwork.kernel.org/project/bluetooth/list/?series=583423
>
> Thanks,
> Manish.
>
> (no changes since v6)
>
> Changes in v6:
> - Fix compiler warning bt_dev_err() missing argument.
>
> Changes in v5:
> - Split v4 into two patches.
> - Buffer controller Device Found event and maintain the device tracking
> state in the kernel.
>
> Changes in v4:
> - Add Advertisement Monitor Device Found event and update addr type.
>
> Changes in v3:
> - Discard changes to the Device Found event and notify bluetoothd only
> when the controller stops monitoring the device via new Device Lost
> event.
>
> Changes in v2:
> - Instead of creating a new 'Device Tracking' event, add a flag 'Device
> Tracked' in the existing 'Device Found' event and add a new 'Device
> Lost' event to indicate that the controller has stopped tracking that
> device.
>
> include/net/bluetooth/hci_core.h | 11 +++
> net/bluetooth/hci_core.c | 1 +
> net/bluetooth/msft.c | 127 ++++++++++++++++++++++++++++++-
> 3 files changed, 138 insertions(+), 1 deletion(-)
>
> diff --git a/include/net/bluetooth/hci_core.h b/include/net/bluetooth/hci_core.h
> index 7bae8376fd6f..5ccd19dec77c 100644
> --- a/include/net/bluetooth/hci_core.h
> +++ b/include/net/bluetooth/hci_core.h
> @@ -258,6 +258,15 @@ struct adv_info {
>
> #define HCI_ADV_TX_POWER_NO_PREFERENCE 0x7F
>
> +struct monitored_device {
> + struct list_head list;
> +
> + bdaddr_t bdaddr;
> + __u8 addr_type;
> + __u16 handle;
> + bool notified;
> +};
> +
> struct adv_pattern {
> struct list_head list;
> __u8 ad_type;
> @@ -589,6 +598,8 @@ struct hci_dev {
>
> struct delayed_work interleave_scan;
>
> + struct list_head monitored_devices;
> +
> #if IS_ENABLED(CONFIG_BT_LEDS)
> struct led_trigger *power_led;
> #endif
> diff --git a/net/bluetooth/hci_core.c b/net/bluetooth/hci_core.c
> index fdc0dcf8ee36..d4bcd511530a 100644
> --- a/net/bluetooth/hci_core.c
> +++ b/net/bluetooth/hci_core.c
> @@ -2503,6 +2503,7 @@ struct hci_dev *hci_alloc_dev_priv(int sizeof_priv)
> INIT_LIST_HEAD(&hdev->conn_hash.list);
> INIT_LIST_HEAD(&hdev->adv_instances);
> INIT_LIST_HEAD(&hdev->blocked_keys);
> + INIT_LIST_HEAD(&hdev->monitored_devices);
>
> INIT_LIST_HEAD(&hdev->local_codecs);
> INIT_WORK(&hdev->rx_work, hci_rx_work);
> diff --git a/net/bluetooth/msft.c b/net/bluetooth/msft.c
> index 1122097e1e49..aadabe78baf6 100644
> --- a/net/bluetooth/msft.c
> +++ b/net/bluetooth/msft.c
> @@ -80,6 +80,14 @@ struct msft_rp_le_set_advertisement_filter_enable {
> __u8 sub_opcode;
> } __packed;
>
> +#define MSFT_EV_LE_MONITOR_DEVICE 0x02
> +struct msft_ev_le_monitor_device {
> + __u8 addr_type;
> + bdaddr_t bdaddr;
> + __u8 monitor_handle;
> + __u8 monitor_state;
> +} __packed;
> +
> struct msft_monitor_advertisement_handle_data {
> __u8 msft_handle;
> __u16 mgmt_handle;
> @@ -266,6 +274,7 @@ static void msft_le_cancel_monitor_advertisement_cb(struct hci_dev *hdev,
> struct msft_data *msft = hdev->msft_data;
> int err;
> bool pending;
> + struct monitored_device *dev, *tmp;
>
> if (status)
> goto done;
> @@ -296,6 +305,15 @@ static void msft_le_cancel_monitor_advertisement_cb(struct hci_dev *hdev,
>
> list_del(&handle_data->list);
> kfree(handle_data);
> +
> + /* Clear any monitored devices by this Adv Monitor */
> + list_for_each_entry_safe(dev, tmp, &hdev->monitored_devices,
> + list) {
> + if (dev->handle == handle_data->mgmt_handle) {
> + list_del(&dev->list);
> + kfree(dev);
> + }
> + }
> }
>
> /* If remove all monitors is required, we need to continue the process
> @@ -538,6 +556,7 @@ void msft_do_close(struct hci_dev *hdev)
> struct msft_data *msft = hdev->msft_data;
> struct msft_monitor_advertisement_handle_data *handle_data, *tmp;
> struct adv_monitor *monitor;
> + struct monitored_device *dev, *tmp_dev;
>
> if (!msft)
> return;
> @@ -557,6 +576,16 @@ void msft_do_close(struct hci_dev *hdev)
> list_del(&handle_data->list);
> kfree(handle_data);
> }
> +
> + hci_dev_lock(hdev);
> +
> + /* Clear any devices that are being monitored */
> + list_for_each_entry_safe(dev, tmp_dev, &hdev->monitored_devices, list) {
> + list_del(&dev->list);
> + kfree(dev);
> + }
> +
> + hci_dev_unlock(hdev);
> }
>
> void msft_register(struct hci_dev *hdev)
> @@ -590,6 +619,90 @@ void msft_unregister(struct hci_dev *hdev)
> kfree(msft);
> }
>
> +/* This function requires the caller holds hdev->lock */
> +static void msft_device_found(struct hci_dev *hdev, bdaddr_t *bdaddr,
> + __u8 addr_type, __u16 mgmt_handle)
> +{
> + struct monitored_device *dev;
> +
> + dev = kmalloc(sizeof(*dev), GFP_KERNEL);
> + if (!dev) {
> + bt_dev_err(hdev, "MSFT vendor event %u: no memory",
> + MSFT_EV_LE_MONITOR_DEVICE);
> + return;
> + }
> +
> + bacpy(&dev->bdaddr, bdaddr);
> + dev->addr_type = addr_type;
> + dev->handle = mgmt_handle;
> + dev->notified = false;
> +
> + INIT_LIST_HEAD(&dev->list);
> + list_add(&dev->list, &hdev->monitored_devices);
> +}
> +
> +/* This function requires the caller holds hdev->lock */
> +static void msft_device_lost(struct hci_dev *hdev, bdaddr_t *bdaddr,
> + __u8 addr_type, __u16 mgmt_handle)
> +{
> + struct monitored_device *dev, *tmp;
> +
> + list_for_each_entry_safe(dev, tmp, &hdev->monitored_devices, list) {
> + if (dev->handle == mgmt_handle) {
> + list_del(&dev->list);
> + kfree(dev);
> +
> + break;
> + }
> + }
> +}
> +
> +/* This function requires the caller holds hdev->lock */
> +static void msft_monitor_device_evt(struct hci_dev *hdev, struct sk_buff *skb)
> +{
> + struct msft_ev_le_monitor_device *ev = (void *)skb->data;
> + struct msft_monitor_advertisement_handle_data *handle_data;
> + u8 addr_type;
> +
> + if (skb->len < sizeof(*ev)) {
> + bt_dev_err(hdev,
> + "MSFT vendor event %u: insufficient data (len: %u)",
> + MSFT_EV_LE_MONITOR_DEVICE, skb->len);
> + return;
> + }
> + skb_pull(skb, sizeof(*ev));

Please use skb_pull_data now that it is available in bluetooth-next.

> + bt_dev_dbg(hdev,
> + "MSFT vendor event %u: handle 0x%04x state %d addr %pMR",
> + MSFT_EV_LE_MONITOR_DEVICE, ev->monitor_handle,
> + ev->monitor_state, &ev->bdaddr);
> +
> + handle_data = msft_find_handle_data(hdev, ev->monitor_handle, false);
> +
> + switch (ev->addr_type) {
> + case ADDR_LE_DEV_PUBLIC:
> + addr_type = BDADDR_LE_PUBLIC;
> + break;
> +
> + case ADDR_LE_DEV_RANDOM:
> + addr_type = BDADDR_LE_RANDOM;
> + break;
> +
> + default:
> + bt_dev_err(hdev,
> + "MSFT vendor event %u: unknown addr type 0x%02x",
> + MSFT_EV_LE_MONITOR_DEVICE, ev->addr_type);
> + return;
> + }
> +
> + if (ev->monitor_state)
> + msft_device_found(hdev, &ev->bdaddr, addr_type,
> + handle_data->mgmt_handle);
> + else
> + msft_device_lost(hdev, &ev->bdaddr, addr_type,
> + handle_data->mgmt_handle);
> +}
> +
> void msft_vendor_evt(struct hci_dev *hdev, struct sk_buff *skb)
> {
> struct msft_data *msft = hdev->msft_data;
> @@ -617,10 +730,22 @@ void msft_vendor_evt(struct hci_dev *hdev, struct sk_buff *skb)
> if (skb->len < 1)
> return;
>
> + hci_dev_lock(hdev);
> +
> event = *skb->data;
> skb_pull(skb, 1);
>
> - bt_dev_dbg(hdev, "MSFT vendor event %u", event);
> + switch (event) {
> + case MSFT_EV_LE_MONITOR_DEVICE:
> + msft_monitor_device_evt(hdev, skb);
> + break;
> +
> + default:
> + bt_dev_dbg(hdev, "MSFT vendor event %u", event);
> + break;
> + }
> +
> + hci_dev_unlock(hdev);
> }
>
> __u64 msft_get_features(struct hci_dev *hdev)
> --
> 2.34.0.384.gca35af8252-goog
>


--
Luiz Augusto von Dentz

2021-12-03 22:19:13

by Luiz Augusto von Dentz

[permalink] [raw]
Subject: Re: [PATCH v7 2/2] bluetooth: Add MGMT Adv Monitor Device Found/Lost events

Hi Manish,

On Thu, Dec 2, 2021 at 11:16 PM Manish Mandlik <[email protected]> wrote:
>
> This patch introduces two new MGMT events for notifying the bluetoothd
> whenever the controller starts/stops monitoring a device.
>
> Test performed:
> - Verified by logs that the MSFT Monitor Device is received from the
> controller and the bluetoothd is notified whenever the controller
> starts/stops monitoring a device.
>
> Signed-off-by: Manish Mandlik <[email protected]>
> Reviewed-by: Miao-chen Chou <[email protected]>
>
> ---
>
> Changes in v7:
> - Refactor mgmt_device_found() to fix stack frame size limit
>
> Changes in v6:
> - Fix compiler warning for mgmt_adv_monitor_device_found().
>
> Changes in v5:
> - New patch in the series. Split previous patch into two.
> - Update the Device Found logic to send existing Device Found event or
> Adv Monitor Device Found event depending on the active scanning state.
>
> include/net/bluetooth/hci_core.h | 3 +
> include/net/bluetooth/mgmt.h | 16 +++++
> net/bluetooth/mgmt.c | 106 +++++++++++++++++++++++++++++--
> net/bluetooth/msft.c | 15 ++++-
> 4 files changed, 134 insertions(+), 6 deletions(-)
>
> diff --git a/include/net/bluetooth/hci_core.h b/include/net/bluetooth/hci_core.h
> index 5ccd19dec77c..3b53214ff49f 100644
> --- a/include/net/bluetooth/hci_core.h
> +++ b/include/net/bluetooth/hci_core.h
> @@ -599,6 +599,7 @@ struct hci_dev {
> struct delayed_work interleave_scan;
>
> struct list_head monitored_devices;
> + bool advmon_pend_notify;
>
> #if IS_ENABLED(CONFIG_BT_LEDS)
> struct led_trigger *power_led;
> @@ -1847,6 +1848,8 @@ void mgmt_adv_monitor_removed(struct hci_dev *hdev, u16 handle);
> int mgmt_phy_configuration_changed(struct hci_dev *hdev, struct sock *skip);
> int mgmt_add_adv_patterns_monitor_complete(struct hci_dev *hdev, u8 status);
> int mgmt_remove_adv_monitor_complete(struct hci_dev *hdev, u8 status);
> +void mgmt_adv_monitor_device_lost(struct hci_dev *hdev, u16 handle,
> + bdaddr_t *bdaddr, u8 addr_type);
>
> u8 hci_le_conn_update(struct hci_conn *conn, u16 min, u16 max, u16 latency,
> u16 to_multiplier);
> diff --git a/include/net/bluetooth/mgmt.h b/include/net/bluetooth/mgmt.h
> index 107b25deae68..99266f7aebdc 100644
> --- a/include/net/bluetooth/mgmt.h
> +++ b/include/net/bluetooth/mgmt.h
> @@ -1104,3 +1104,19 @@ struct mgmt_ev_controller_resume {
> #define MGMT_WAKE_REASON_NON_BT_WAKE 0x0
> #define MGMT_WAKE_REASON_UNEXPECTED 0x1
> #define MGMT_WAKE_REASON_REMOTE_WAKE 0x2
> +
> +#define MGMT_EV_ADV_MONITOR_DEVICE_FOUND 0x002f
> +struct mgmt_ev_adv_monitor_device_found {
> + __le16 monitor_handle;
> + struct mgmt_addr_info addr;
> + __s8 rssi;
> + __le32 flags;
> + __le16 eir_len;
> + __u8 eir[0];
> +} __packed;
> +
> +#define MGMT_EV_ADV_MONITOR_DEVICE_LOST 0x0030
> +struct mgmt_ev_adv_monitor_device_lost {
> + __le16 monitor_handle;
> + struct mgmt_addr_info addr;
> +} __packed;
> diff --git a/net/bluetooth/mgmt.c b/net/bluetooth/mgmt.c
> index bf989ae03f9f..06e0769f350d 100644
> --- a/net/bluetooth/mgmt.c
> +++ b/net/bluetooth/mgmt.c
> @@ -174,6 +174,8 @@ static const u16 mgmt_events[] = {
> MGMT_EV_ADV_MONITOR_REMOVED,
> MGMT_EV_CONTROLLER_SUSPEND,
> MGMT_EV_CONTROLLER_RESUME,
> + MGMT_EV_ADV_MONITOR_DEVICE_FOUND,
> + MGMT_EV_ADV_MONITOR_DEVICE_LOST,
> };
>
> static const u16 mgmt_untrusted_commands[] = {
> @@ -9524,6 +9526,100 @@ static bool is_filter_match(struct hci_dev *hdev, s8 rssi, u8 *eir,
> return true;
> }
>
> +void mgmt_adv_monitor_device_lost(struct hci_dev *hdev, u16 handle,
> + bdaddr_t *bdaddr, u8 addr_type)
> +{
> + struct mgmt_ev_adv_monitor_device_lost ev;
> +
> + ev.monitor_handle = cpu_to_le16(handle);
> + bacpy(&ev.addr.bdaddr, bdaddr);
> + ev.addr.type = addr_type;
> +
> + mgmt_event(MGMT_EV_ADV_MONITOR_DEVICE_LOST, hdev, &ev, sizeof(ev),
> + NULL);
> +}
> +
> +static void mgmt_adv_monitor_device_found(struct hci_dev *hdev,
> + struct mgmt_ev_device_found *ev,
> + size_t ev_size, bool discovering)
> +{
> + char buf[518];

We should try to avoid declaring such big stack variable, instead Im
working on a set the should enable you to use skb_put/skb_put_data
directly into the skb, here are the current changes I have for
device_found:

https://gist.github.com/Vudentz/ffce584912eb7dc4add9c3bb25466fa5

I'm addressing Marcel's comments and will send the set to the list later today.

> + struct mgmt_ev_adv_monitor_device_found *advmon_ev = (void *)buf;
> + size_t advmon_ev_size;
> + struct monitored_device *dev, *tmp;
> + bool matched = false;
> + bool notified = false;
> +
> + /* We have received the Advertisement Report because:
> + * 1. the kernel has initiated active discovery
> + * 2. if not, we have pend_le_reports > 0 in which case we are doing
> + * passive scanning
> + * 3. if none of the above is true, we have one or more active
> + * Advertisement Monitor
> + *
> + * For case 1 and 2, report all advertisements via MGMT_EV_DEVICE_FOUND
> + * and report ONLY one advertisement per device for the matched Monitor
> + * via MGMT_EV_ADV_MONITOR_DEVICE_FOUND event.
> + *
> + * For case 3, since we are not active scanning and all advertisements
> + * received are due to a matched Advertisement Monitor, report all
> + * advertisements ONLY via MGMT_EV_ADV_MONITOR_DEVICE_FOUND event.
> + */
> + if (discovering) {
> + mgmt_event(MGMT_EV_DEVICE_FOUND, hdev, ev, ev_size, NULL);
> +
> + if (!hdev->advmon_pend_notify)
> + return;
> + }
> +
> + /* Make sure that the buffer is big enough */
> + advmon_ev_size = ev_size + (sizeof(*advmon_ev) - sizeof(*ev));
> + if (advmon_ev_size > sizeof(buf))
> + return;
> +
> + /* ADV_MONITOR_DEVICE_FOUND is similar to DEVICE_FOUND event except
> + * that it also has 'monitor_handle'. Make a copy of DEVICE_FOUND and
> + * store monitor_handle of the matched monitor.
> + */
> + memcpy(&advmon_ev->addr, ev, ev_size);
> +
> + hdev->advmon_pend_notify = false;
> +
> + list_for_each_entry_safe(dev, tmp, &hdev->monitored_devices, list) {
> + if (!bacmp(&dev->bdaddr, &advmon_ev->addr.bdaddr)) {
> + matched = true;
> +
> + if (!dev->notified) {
> + advmon_ev->monitor_handle =
> + cpu_to_le16(dev->handle);
> +
> + mgmt_event(MGMT_EV_ADV_MONITOR_DEVICE_FOUND,
> + hdev, advmon_ev, advmon_ev_size,
> + NULL);
> +
> + notified = true;
> + dev->notified = true;
> + }
> + }
> +
> + if (!dev->notified)
> + hdev->advmon_pend_notify = true;
> + }
> +
> + if (!discovering &&
> + ((matched && !notified) || !msft_monitor_supported(hdev))) {
> + /* Handle 0 indicates that we are not active scanning and this
> + * is a subsequent advertisement report for an already matched
> + * Advertisement Monitor or the controller offloading support
> + * is not available.
> + */
> + advmon_ev->monitor_handle = 0;
> +
> + mgmt_event(MGMT_EV_ADV_MONITOR_DEVICE_FOUND, hdev, advmon_ev,
> + advmon_ev_size, NULL);
> + }
> +}
> +
> void mgmt_device_found(struct hci_dev *hdev, bdaddr_t *bdaddr, u8 link_type,
> u8 addr_type, u8 *dev_class, s8 rssi, u32 flags,
> u8 *eir, u16 eir_len, u8 *scan_rsp, u8 scan_rsp_len)
> @@ -9531,6 +9627,7 @@ void mgmt_device_found(struct hci_dev *hdev, bdaddr_t *bdaddr, u8 link_type,
> char buf[512];
> struct mgmt_ev_device_found *ev = (void *)buf;
> size_t ev_size;
> + bool report_device_found = hci_discovery_active(hdev);
>
> /* Don't send events for a non-kernel initiated discovery. With
> * LE one exception is if we have pend_le_reports > 0 in which
> @@ -9539,11 +9636,10 @@ void mgmt_device_found(struct hci_dev *hdev, bdaddr_t *bdaddr, u8 link_type,
> if (!hci_discovery_active(hdev)) {
> if (link_type == ACL_LINK)
> return;
> - if (link_type == LE_LINK &&
> - list_empty(&hdev->pend_le_reports) &&
> - !hci_is_adv_monitoring(hdev)) {
> + if (link_type == LE_LINK && !list_empty(&hdev->pend_le_reports))
> + report_device_found = true;
> + else if (!hci_is_adv_monitoring(hdev))
> return;
> - }
> }
>
> if (hdev->discovery.result_filtering) {
> @@ -9606,7 +9702,7 @@ void mgmt_device_found(struct hci_dev *hdev, bdaddr_t *bdaddr, u8 link_type,
> ev->eir_len = cpu_to_le16(eir_len + scan_rsp_len);
> ev_size = sizeof(*ev) + eir_len + scan_rsp_len;
>
> - mgmt_event(MGMT_EV_DEVICE_FOUND, hdev, ev, ev_size, NULL);
> + mgmt_adv_monitor_device_found(hdev, ev, ev_size, report_device_found);
> }
>
> void mgmt_remote_name(struct hci_dev *hdev, bdaddr_t *bdaddr, u8 link_type,
> diff --git a/net/bluetooth/msft.c b/net/bluetooth/msft.c
> index aadabe78baf6..3e2385562d2b 100644
> --- a/net/bluetooth/msft.c
> +++ b/net/bluetooth/msft.c
> @@ -579,8 +579,16 @@ void msft_do_close(struct hci_dev *hdev)
>
> hci_dev_lock(hdev);
>
> - /* Clear any devices that are being monitored */
> + /* Clear any devices that are being monitored and notify device lost */
> +
> + hdev->advmon_pend_notify = false;
> +
> list_for_each_entry_safe(dev, tmp_dev, &hdev->monitored_devices, list) {
> + if (dev->notified)
> + mgmt_adv_monitor_device_lost(hdev, dev->handle,
> + &dev->bdaddr,
> + dev->addr_type);
> +
> list_del(&dev->list);
> kfree(dev);
> }
> @@ -639,6 +647,7 @@ static void msft_device_found(struct hci_dev *hdev, bdaddr_t *bdaddr,
>
> INIT_LIST_HEAD(&dev->list);
> list_add(&dev->list, &hdev->monitored_devices);
> + hdev->advmon_pend_notify = true;
> }
>
> /* This function requires the caller holds hdev->lock */
> @@ -649,6 +658,10 @@ static void msft_device_lost(struct hci_dev *hdev, bdaddr_t *bdaddr,
>
> list_for_each_entry_safe(dev, tmp, &hdev->monitored_devices, list) {
> if (dev->handle == mgmt_handle) {
> + if (dev->notified)
> + mgmt_adv_monitor_device_lost(hdev, mgmt_handle,
> + bdaddr, addr_type);
> +
> list_del(&dev->list);
> kfree(dev);
>
> --
> 2.34.0.384.gca35af8252-goog
>


--
Luiz Augusto von Dentz

2021-12-06 13:58:30

by Dan Carpenter

[permalink] [raw]
Subject: Re: [PATCH v7 1/2] bluetooth: Handle MSFT Monitor Device Event

Hi Manish,

url: https://github.com/0day-ci/linux/commits/Manish-Mandlik/bluetooth-Handle-MSFT-Monitor-Device-Event/20211203-151659
base: https://git.kernel.org/pub/scm/linux/kernel/git/bluetooth/bluetooth-next.git master
config: x86_64-randconfig-m001-20211203 (https://download.01.org/0day-ci/archive/20211205/[email protected]/config)
compiler: gcc-9 (Debian 9.3.0-22) 9.3.0

If you fix the issue, kindly add following tag as appropriate
Reported-by: kernel test robot <[email protected]>
Reported-by: Dan Carpenter <[email protected]>

smatch warnings:
net/bluetooth/msft.c:312 msft_le_cancel_monitor_advertisement_cb() error: dereferencing freed memory 'handle_data'

vim +/handle_data +312 net/bluetooth/msft.c

182ee45da083db Luiz Augusto von Dentz 2021-10-27 266 static void msft_le_cancel_monitor_advertisement_cb(struct hci_dev *hdev,
182ee45da083db Luiz Augusto von Dentz 2021-10-27 267 u8 status, u16 opcode,
182ee45da083db Luiz Augusto von Dentz 2021-10-27 268 struct sk_buff *skb)
ce81843be24e9d Manish Mandlik 2021-09-21 269 {
182ee45da083db Luiz Augusto von Dentz 2021-10-27 270 struct msft_cp_le_cancel_monitor_advertisement *cp;
182ee45da083db Luiz Augusto von Dentz 2021-10-27 271 struct msft_rp_le_cancel_monitor_advertisement *rp;
182ee45da083db Luiz Augusto von Dentz 2021-10-27 272 struct adv_monitor *monitor;
182ee45da083db Luiz Augusto von Dentz 2021-10-27 273 struct msft_monitor_advertisement_handle_data *handle_data;
ce81843be24e9d Manish Mandlik 2021-09-21 274 struct msft_data *msft = hdev->msft_data;
182ee45da083db Luiz Augusto von Dentz 2021-10-27 275 int err;
182ee45da083db Luiz Augusto von Dentz 2021-10-27 276 bool pending;
eb96f195e598b7 Manish Mandlik 2021-12-02 277 struct monitored_device *dev, *tmp;
ce81843be24e9d Manish Mandlik 2021-09-21 278
182ee45da083db Luiz Augusto von Dentz 2021-10-27 279 if (status)
182ee45da083db Luiz Augusto von Dentz 2021-10-27 280 goto done;
182ee45da083db Luiz Augusto von Dentz 2021-10-27 281
182ee45da083db Luiz Augusto von Dentz 2021-10-27 282 rp = (struct msft_rp_le_cancel_monitor_advertisement *)skb->data;
182ee45da083db Luiz Augusto von Dentz 2021-10-27 283 if (skb->len < sizeof(*rp)) {
182ee45da083db Luiz Augusto von Dentz 2021-10-27 284 status = HCI_ERROR_UNSPECIFIED;
182ee45da083db Luiz Augusto von Dentz 2021-10-27 285 goto done;
182ee45da083db Luiz Augusto von Dentz 2021-10-27 286 }
182ee45da083db Luiz Augusto von Dentz 2021-10-27 287
182ee45da083db Luiz Augusto von Dentz 2021-10-27 288 hci_dev_lock(hdev);
182ee45da083db Luiz Augusto von Dentz 2021-10-27 289
182ee45da083db Luiz Augusto von Dentz 2021-10-27 290 cp = hci_sent_cmd_data(hdev, hdev->msft_opcode);
182ee45da083db Luiz Augusto von Dentz 2021-10-27 291 handle_data = msft_find_handle_data(hdev, cp->handle, false);
182ee45da083db Luiz Augusto von Dentz 2021-10-27 292
182ee45da083db Luiz Augusto von Dentz 2021-10-27 293 if (handle_data) {
182ee45da083db Luiz Augusto von Dentz 2021-10-27 294 monitor = idr_find(&hdev->adv_monitors_idr,
182ee45da083db Luiz Augusto von Dentz 2021-10-27 295 handle_data->mgmt_handle);
182ee45da083db Luiz Augusto von Dentz 2021-10-27 296
182ee45da083db Luiz Augusto von Dentz 2021-10-27 297 if (monitor && monitor->state == ADV_MONITOR_STATE_OFFLOADED)
182ee45da083db Luiz Augusto von Dentz 2021-10-27 298 monitor->state = ADV_MONITOR_STATE_REGISTERED;
182ee45da083db Luiz Augusto von Dentz 2021-10-27 299
182ee45da083db Luiz Augusto von Dentz 2021-10-27 300 /* Do not free the monitor if it is being removed due to
182ee45da083db Luiz Augusto von Dentz 2021-10-27 301 * suspend. It will be re-monitored on resume.
182ee45da083db Luiz Augusto von Dentz 2021-10-27 302 */
182ee45da083db Luiz Augusto von Dentz 2021-10-27 303 if (monitor && !msft->suspending)
182ee45da083db Luiz Augusto von Dentz 2021-10-27 304 hci_free_adv_monitor(hdev, monitor);
182ee45da083db Luiz Augusto von Dentz 2021-10-27 305
182ee45da083db Luiz Augusto von Dentz 2021-10-27 306 list_del(&handle_data->list);
182ee45da083db Luiz Augusto von Dentz 2021-10-27 307 kfree(handle_data);
^^^^^^^^^^^^^^^^^^
Free

eb96f195e598b7 Manish Mandlik 2021-12-02 308
eb96f195e598b7 Manish Mandlik 2021-12-02 309 /* Clear any monitored devices by this Adv Monitor */
eb96f195e598b7 Manish Mandlik 2021-12-02 310 list_for_each_entry_safe(dev, tmp, &hdev->monitored_devices,
eb96f195e598b7 Manish Mandlik 2021-12-02 311 list) {
eb96f195e598b7 Manish Mandlik 2021-12-02 @312 if (dev->handle == handle_data->mgmt_handle) {
^^^^^^^^^^^^^^^^^^^^^^^^
Use after free.

eb96f195e598b7 Manish Mandlik 2021-12-02 313 list_del(&dev->list);
eb96f195e598b7 Manish Mandlik 2021-12-02 314 kfree(dev);
eb96f195e598b7 Manish Mandlik 2021-12-02 315 }
eb96f195e598b7 Manish Mandlik 2021-12-02 316 }
182ee45da083db Luiz Augusto von Dentz 2021-10-27 317 }
182ee45da083db Luiz Augusto von Dentz 2021-10-27 318
182ee45da083db Luiz Augusto von Dentz 2021-10-27 319 /* If remove all monitors is required, we need to continue the process
182ee45da083db Luiz Augusto von Dentz 2021-10-27 320 * here because the earlier it was paused when waiting for the
182ee45da083db Luiz Augusto von Dentz 2021-10-27 321 * response from controller.
182ee45da083db Luiz Augusto von Dentz 2021-10-27 322 */
182ee45da083db Luiz Augusto von Dentz 2021-10-27 323 if (msft->pending_remove_handle == 0) {
182ee45da083db Luiz Augusto von Dentz 2021-10-27 324 pending = hci_remove_all_adv_monitor(hdev, &err);
182ee45da083db Luiz Augusto von Dentz 2021-10-27 325 if (pending) {
182ee45da083db Luiz Augusto von Dentz 2021-10-27 326 hci_dev_unlock(hdev);
ce81843be24e9d Manish Mandlik 2021-09-21 327 return;
182ee45da083db Luiz Augusto von Dentz 2021-10-27 328 }
182ee45da083db Luiz Augusto von Dentz 2021-10-27 329
182ee45da083db Luiz Augusto von Dentz 2021-10-27 330 if (err)
182ee45da083db Luiz Augusto von Dentz 2021-10-27 331 status = HCI_ERROR_UNSPECIFIED;
182ee45da083db Luiz Augusto von Dentz 2021-10-27 332 }
182ee45da083db Luiz Augusto von Dentz 2021-10-27 333
182ee45da083db Luiz Augusto von Dentz 2021-10-27 334 hci_dev_unlock(hdev);
182ee45da083db Luiz Augusto von Dentz 2021-10-27 335
182ee45da083db Luiz Augusto von Dentz 2021-10-27 336 done:
182ee45da083db Luiz Augusto von Dentz 2021-10-27 337 if (!msft->suspending)
182ee45da083db Luiz Augusto von Dentz 2021-10-27 338 hci_remove_adv_monitor_complete(hdev, status);
182ee45da083db Luiz Augusto von Dentz 2021-10-27 339 }

---
0-DAY CI Kernel Test Service, Intel Corporation
https://lists.01.org/hyperkitty/list/[email protected]


2021-12-13 17:21:12

by Luiz Augusto von Dentz

[permalink] [raw]
Subject: Re: [PATCH v7 2/2] bluetooth: Add MGMT Adv Monitor Device Found/Lost events

Hi Manish,

On Mon, Dec 6, 2021 at 8:39 AM Manish Mandlik <[email protected]> wrote:
>
> Hi Luiz,
>
> On Fri, Dec 3, 2021 at 5:19 PM Luiz Augusto von Dentz <[email protected]> wrote:
>>
>> Hi Manish,
>>
>> On Thu, Dec 2, 2021 at 11:16 PM Manish Mandlik <[email protected]> wrote:
>> >
>> > This patch introduces two new MGMT events for notifying the bluetoothd
>> > whenever the controller starts/stops monitoring a device.
>> >
>> > Test performed:
>> > - Verified by logs that the MSFT Monitor Device is received from the
>> > controller and the bluetoothd is notified whenever the controller
>> > starts/stops monitoring a device.
>> >
>> > Signed-off-by: Manish Mandlik <[email protected]>
>> > Reviewed-by: Miao-chen Chou <[email protected]>
>> >
>> > ---
>> >
>> > Changes in v7:
>> > - Refactor mgmt_device_found() to fix stack frame size limit
>> >
>> > Changes in v6:
>> > - Fix compiler warning for mgmt_adv_monitor_device_found().
>> >
>> > Changes in v5:
>> > - New patch in the series. Split previous patch into two.
>> > - Update the Device Found logic to send existing Device Found event or
>> > Adv Monitor Device Found event depending on the active scanning state.
>> >
>> > include/net/bluetooth/hci_core.h | 3 +
>> > include/net/bluetooth/mgmt.h | 16 +++++
>> > net/bluetooth/mgmt.c | 106 +++++++++++++++++++++++++++++--
>> > net/bluetooth/msft.c | 15 ++++-
>> > 4 files changed, 134 insertions(+), 6 deletions(-)
>> >
>> > diff --git a/include/net/bluetooth/hci_core.h b/include/net/bluetooth/hci_core.h
>> > index 5ccd19dec77c..3b53214ff49f 100644
>> > --- a/include/net/bluetooth/hci_core.h
>> > +++ b/include/net/bluetooth/hci_core.h
>> > @@ -599,6 +599,7 @@ struct hci_dev {
>> > struct delayed_work interleave_scan;
>> >
>> > struct list_head monitored_devices;
>> > + bool advmon_pend_notify;
>> >
>> > #if IS_ENABLED(CONFIG_BT_LEDS)
>> > struct led_trigger *power_led;
>> > @@ -1847,6 +1848,8 @@ void mgmt_adv_monitor_removed(struct hci_dev *hdev, u16 handle);
>> > int mgmt_phy_configuration_changed(struct hci_dev *hdev, struct sock *skip);
>> > int mgmt_add_adv_patterns_monitor_complete(struct hci_dev *hdev, u8 status);
>> > int mgmt_remove_adv_monitor_complete(struct hci_dev *hdev, u8 status);
>> > +void mgmt_adv_monitor_device_lost(struct hci_dev *hdev, u16 handle,
>> > + bdaddr_t *bdaddr, u8 addr_type);
>> >
>> > u8 hci_le_conn_update(struct hci_conn *conn, u16 min, u16 max, u16 latency,
>> > u16 to_multiplier);
>> > diff --git a/include/net/bluetooth/mgmt.h b/include/net/bluetooth/mgmt.h
>> > index 107b25deae68..99266f7aebdc 100644
>> > --- a/include/net/bluetooth/mgmt.h
>> > +++ b/include/net/bluetooth/mgmt.h
>> > @@ -1104,3 +1104,19 @@ struct mgmt_ev_controller_resume {
>> > #define MGMT_WAKE_REASON_NON_BT_WAKE 0x0
>> > #define MGMT_WAKE_REASON_UNEXPECTED 0x1
>> > #define MGMT_WAKE_REASON_REMOTE_WAKE 0x2
>> > +
>> > +#define MGMT_EV_ADV_MONITOR_DEVICE_FOUND 0x002f
>> > +struct mgmt_ev_adv_monitor_device_found {
>> > + __le16 monitor_handle;
>> > + struct mgmt_addr_info addr;
>> > + __s8 rssi;
>> > + __le32 flags;
>> > + __le16 eir_len;
>> > + __u8 eir[0];
>> > +} __packed;
>> > +
>> > +#define MGMT_EV_ADV_MONITOR_DEVICE_LOST 0x0030
>> > +struct mgmt_ev_adv_monitor_device_lost {
>> > + __le16 monitor_handle;
>> > + struct mgmt_addr_info addr;
>> > +} __packed;
>> > diff --git a/net/bluetooth/mgmt.c b/net/bluetooth/mgmt.c
>> > index bf989ae03f9f..06e0769f350d 100644
>> > --- a/net/bluetooth/mgmt.c
>> > +++ b/net/bluetooth/mgmt.c
>> > @@ -174,6 +174,8 @@ static const u16 mgmt_events[] = {
>> > MGMT_EV_ADV_MONITOR_REMOVED,
>> > MGMT_EV_CONTROLLER_SUSPEND,
>> > MGMT_EV_CONTROLLER_RESUME,
>> > + MGMT_EV_ADV_MONITOR_DEVICE_FOUND,
>> > + MGMT_EV_ADV_MONITOR_DEVICE_LOST,
>> > };
>> >
>> > static const u16 mgmt_untrusted_commands[] = {
>> > @@ -9524,6 +9526,100 @@ static bool is_filter_match(struct hci_dev *hdev, s8 rssi, u8 *eir,
>> > return true;
>> > }
>> >
>> > +void mgmt_adv_monitor_device_lost(struct hci_dev *hdev, u16 handle,
>> > + bdaddr_t *bdaddr, u8 addr_type)
>> > +{
>> > + struct mgmt_ev_adv_monitor_device_lost ev;
>> > +
>> > + ev.monitor_handle = cpu_to_le16(handle);
>> > + bacpy(&ev.addr.bdaddr, bdaddr);
>> > + ev.addr.type = addr_type;
>> > +
>> > + mgmt_event(MGMT_EV_ADV_MONITOR_DEVICE_LOST, hdev, &ev, sizeof(ev),
>> > + NULL);
>> > +}
>> > +
>> > +static void mgmt_adv_monitor_device_found(struct hci_dev *hdev,
>> > + struct mgmt_ev_device_found *ev,
>> > + size_t ev_size, bool discovering)
>> > +{
>> > + char buf[518];
>>
>> We should try to avoid declaring such big stack variable, instead Im
>> working on a set the should enable you to use skb_put/skb_put_data
>> directly into the skb, here are the current changes I have for
>> device_found:
>>
>> https://gist.github.com/Vudentz/ffce584912eb7dc4add9c3bb25466fa5
>>
>> I'm addressing Marcel's comments and will send the set to the list later today.
>
> Please let me know once these changes land bluetooth-next, I'll update my patch and send out the new revision.

Those changes are already in bluetooth-next.

>>
>>
>> > + struct mgmt_ev_adv_monitor_device_found *advmon_ev = (void *)buf;
>> > + size_t advmon_ev_size;
>> > + struct monitored_device *dev, *tmp;
>> > + bool matched = false;
>> > + bool notified = false;
>> > +
>> > + /* We have received the Advertisement Report because:
>> > + * 1. the kernel has initiated active discovery
>> > + * 2. if not, we have pend_le_reports > 0 in which case we are doing
>> > + * passive scanning
>> > + * 3. if none of the above is true, we have one or more active
>> > + * Advertisement Monitor
>> > + *
>> > + * For case 1 and 2, report all advertisements via MGMT_EV_DEVICE_FOUND
>> > + * and report ONLY one advertisement per device for the matched Monitor
>> > + * via MGMT_EV_ADV_MONITOR_DEVICE_FOUND event.
>> > + *
>> > + * For case 3, since we are not active scanning and all advertisements
>> > + * received are due to a matched Advertisement Monitor, report all
>> > + * advertisements ONLY via MGMT_EV_ADV_MONITOR_DEVICE_FOUND event.
>> > + */
>> > + if (discovering) {
>> > + mgmt_event(MGMT_EV_DEVICE_FOUND, hdev, ev, ev_size, NULL);
>> > +
>> > + if (!hdev->advmon_pend_notify)
>> > + return;
>> > + }
>> > +
>> > + /* Make sure that the buffer is big enough */
>> > + advmon_ev_size = ev_size + (sizeof(*advmon_ev) - sizeof(*ev));
>> > + if (advmon_ev_size > sizeof(buf))
>> > + return;
>> > +
>> > + /* ADV_MONITOR_DEVICE_FOUND is similar to DEVICE_FOUND event except
>> > + * that it also has 'monitor_handle'. Make a copy of DEVICE_FOUND and
>> > + * store monitor_handle of the matched monitor.
>> > + */
>> > + memcpy(&advmon_ev->addr, ev, ev_size);
>> > +
>> > + hdev->advmon_pend_notify = false;
>> > +
>> > + list_for_each_entry_safe(dev, tmp, &hdev->monitored_devices, list) {
>> > + if (!bacmp(&dev->bdaddr, &advmon_ev->addr.bdaddr)) {
>> > + matched = true;
>> > +
>> > + if (!dev->notified) {
>> > + advmon_ev->monitor_handle =
>> > + cpu_to_le16(dev->handle);
>> > +
>> > + mgmt_event(MGMT_EV_ADV_MONITOR_DEVICE_FOUND,
>> > + hdev, advmon_ev, advmon_ev_size,
>> > + NULL);
>> > +
>> > + notified = true;
>> > + dev->notified = true;
>> > + }
>> > + }
>> > +
>> > + if (!dev->notified)
>> > + hdev->advmon_pend_notify = true;
>> > + }
>> > +
>> > + if (!discovering &&
>> > + ((matched && !notified) || !msft_monitor_supported(hdev))) {
>> > + /* Handle 0 indicates that we are not active scanning and this
>> > + * is a subsequent advertisement report for an already matched
>> > + * Advertisement Monitor or the controller offloading support
>> > + * is not available.
>> > + */
>> > + advmon_ev->monitor_handle = 0;
>> > +
>> > + mgmt_event(MGMT_EV_ADV_MONITOR_DEVICE_FOUND, hdev, advmon_ev,
>> > + advmon_ev_size, NULL);
>> > + }
>> > +}
>> > +
>> > void mgmt_device_found(struct hci_dev *hdev, bdaddr_t *bdaddr, u8 link_type,
>> > u8 addr_type, u8 *dev_class, s8 rssi, u32 flags,
>> > u8 *eir, u16 eir_len, u8 *scan_rsp, u8 scan_rsp_len)
>> > @@ -9531,6 +9627,7 @@ void mgmt_device_found(struct hci_dev *hdev, bdaddr_t *bdaddr, u8 link_type,
>> > char buf[512];
>> > struct mgmt_ev_device_found *ev = (void *)buf;
>> > size_t ev_size;
>> > + bool report_device_found = hci_discovery_active(hdev);
>> >
>> > /* Don't send events for a non-kernel initiated discovery. With
>> > * LE one exception is if we have pend_le_reports > 0 in which
>> > @@ -9539,11 +9636,10 @@ void mgmt_device_found(struct hci_dev *hdev, bdaddr_t *bdaddr, u8 link_type,
>> > if (!hci_discovery_active(hdev)) {
>> > if (link_type == ACL_LINK)
>> > return;
>> > - if (link_type == LE_LINK &&
>> > - list_empty(&hdev->pend_le_reports) &&
>> > - !hci_is_adv_monitoring(hdev)) {
>> > + if (link_type == LE_LINK && !list_empty(&hdev->pend_le_reports))
>> > + report_device_found = true;
>> > + else if (!hci_is_adv_monitoring(hdev))
>> > return;
>> > - }
>> > }
>> >
>> > if (hdev->discovery.result_filtering) {
>> > @@ -9606,7 +9702,7 @@ void mgmt_device_found(struct hci_dev *hdev, bdaddr_t *bdaddr, u8 link_type,
>> > ev->eir_len = cpu_to_le16(eir_len + scan_rsp_len);
>> > ev_size = sizeof(*ev) + eir_len + scan_rsp_len;
>> >
>> > - mgmt_event(MGMT_EV_DEVICE_FOUND, hdev, ev, ev_size, NULL);
>> > + mgmt_adv_monitor_device_found(hdev, ev, ev_size, report_device_found);
>> > }
>> >
>> > void mgmt_remote_name(struct hci_dev *hdev, bdaddr_t *bdaddr, u8 link_type,
>> > diff --git a/net/bluetooth/msft.c b/net/bluetooth/msft.c
>> > index aadabe78baf6..3e2385562d2b 100644
>> > --- a/net/bluetooth/msft.c
>> > +++ b/net/bluetooth/msft.c
>> > @@ -579,8 +579,16 @@ void msft_do_close(struct hci_dev *hdev)
>> >
>> > hci_dev_lock(hdev);
>> >
>> > - /* Clear any devices that are being monitored */
>> > + /* Clear any devices that are being monitored and notify device lost */
>> > +
>> > + hdev->advmon_pend_notify = false;
>> > +
>> > list_for_each_entry_safe(dev, tmp_dev, &hdev->monitored_devices, list) {
>> > + if (dev->notified)
>> > + mgmt_adv_monitor_device_lost(hdev, dev->handle,
>> > + &dev->bdaddr,
>> > + dev->addr_type);
>> > +
>> > list_del(&dev->list);
>> > kfree(dev);
>> > }
>> > @@ -639,6 +647,7 @@ static void msft_device_found(struct hci_dev *hdev, bdaddr_t *bdaddr,
>> >
>> > INIT_LIST_HEAD(&dev->list);
>> > list_add(&dev->list, &hdev->monitored_devices);
>> > + hdev->advmon_pend_notify = true;
>> > }
>> >
>> > /* This function requires the caller holds hdev->lock */
>> > @@ -649,6 +658,10 @@ static void msft_device_lost(struct hci_dev *hdev, bdaddr_t *bdaddr,
>> >
>> > list_for_each_entry_safe(dev, tmp, &hdev->monitored_devices, list) {
>> > if (dev->handle == mgmt_handle) {
>> > + if (dev->notified)
>> > + mgmt_adv_monitor_device_lost(hdev, mgmt_handle,
>> > + bdaddr, addr_type);
>> > +
>> > list_del(&dev->list);
>> > kfree(dev);
>> >
>> > --
>> > 2.34.0.384.gca35af8252-goog
>> >
>>
>>
>> --
>> Luiz Augusto von Dentz
>
>
> Thanks,
> Manish.



--
Luiz Augusto von Dentz