[PATCH 5.13 582/800] Bluetooth: Fix Set Extended (Scan Response) Data

From: Greg Kroah-Hartman
Date: Mon Jul 12 2021 - 04:50:56 EST


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

[ Upstream commit c9ed0a7077306f9d41d74fb006ab5dbada8349c5 ]

These command do have variable length and the length can go up to 251,
so this changes the struct to not use a fixed size and then when
creating the PDU only the actual length of the data send to the
controller.

Fixes: a0fb3726ba551 ("Bluetooth: Use Set ext adv/scan rsp data if controller supports")
Signed-off-by: Luiz Augusto von Dentz <luiz.von.dentz@xxxxxxxxx>
Signed-off-by: Marcel Holtmann <marcel@xxxxxxxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
---
include/net/bluetooth/hci.h | 6 ++--
include/net/bluetooth/hci_core.h | 8 ++---
net/bluetooth/hci_request.c | 51 ++++++++++++++++++--------------
3 files changed, 37 insertions(+), 28 deletions(-)

diff --git a/include/net/bluetooth/hci.h b/include/net/bluetooth/hci.h
index ea4ae551c426..18b135dc968b 100644
--- a/include/net/bluetooth/hci.h
+++ b/include/net/bluetooth/hci.h
@@ -1774,13 +1774,15 @@ struct hci_cp_ext_adv_set {
__u8 max_events;
} __packed;

+#define HCI_MAX_EXT_AD_LENGTH 251
+
#define HCI_OP_LE_SET_EXT_ADV_DATA 0x2037
struct hci_cp_le_set_ext_adv_data {
__u8 handle;
__u8 operation;
__u8 frag_pref;
__u8 length;
- __u8 data[HCI_MAX_AD_LENGTH];
+ __u8 data[];
} __packed;

#define HCI_OP_LE_SET_EXT_SCAN_RSP_DATA 0x2038
@@ -1789,7 +1791,7 @@ struct hci_cp_le_set_ext_scan_rsp_data {
__u8 operation;
__u8 frag_pref;
__u8 length;
- __u8 data[HCI_MAX_AD_LENGTH];
+ __u8 data[];
} __packed;

#define LE_SET_ADV_DATA_OP_COMPLETE 0x03
diff --git a/include/net/bluetooth/hci_core.h b/include/net/bluetooth/hci_core.h
index c73ac52af186..89c8406dddb4 100644
--- a/include/net/bluetooth/hci_core.h
+++ b/include/net/bluetooth/hci_core.h
@@ -228,9 +228,9 @@ struct adv_info {
__u16 remaining_time;
__u16 duration;
__u16 adv_data_len;
- __u8 adv_data[HCI_MAX_AD_LENGTH];
+ __u8 adv_data[HCI_MAX_EXT_AD_LENGTH];
__u16 scan_rsp_len;
- __u8 scan_rsp_data[HCI_MAX_AD_LENGTH];
+ __u8 scan_rsp_data[HCI_MAX_EXT_AD_LENGTH];
__s8 tx_power;
__u32 min_interval;
__u32 max_interval;
@@ -550,9 +550,9 @@ struct hci_dev {
DECLARE_BITMAP(dev_flags, __HCI_NUM_FLAGS);

__s8 adv_tx_power;
- __u8 adv_data[HCI_MAX_AD_LENGTH];
+ __u8 adv_data[HCI_MAX_EXT_AD_LENGTH];
__u8 adv_data_len;
- __u8 scan_rsp_data[HCI_MAX_AD_LENGTH];
+ __u8 scan_rsp_data[HCI_MAX_EXT_AD_LENGTH];
__u8 scan_rsp_data_len;

struct list_head adv_instances;
diff --git a/net/bluetooth/hci_request.c b/net/bluetooth/hci_request.c
index fa9125b782f8..b069f640394d 100644
--- a/net/bluetooth/hci_request.c
+++ b/net/bluetooth/hci_request.c
@@ -1697,30 +1697,33 @@ void __hci_req_update_scan_rsp_data(struct hci_request *req, u8 instance)
return;

if (ext_adv_capable(hdev)) {
- struct hci_cp_le_set_ext_scan_rsp_data cp;
+ struct {
+ struct hci_cp_le_set_ext_scan_rsp_data cp;
+ u8 data[HCI_MAX_EXT_AD_LENGTH];
+ } pdu;

- memset(&cp, 0, sizeof(cp));
+ memset(&pdu, 0, sizeof(pdu));

if (instance)
len = create_instance_scan_rsp_data(hdev, instance,
- cp.data);
+ pdu.data);
else
- len = create_default_scan_rsp_data(hdev, cp.data);
+ len = create_default_scan_rsp_data(hdev, pdu.data);

if (hdev->scan_rsp_data_len == len &&
- !memcmp(cp.data, hdev->scan_rsp_data, len))
+ !memcmp(pdu.data, hdev->scan_rsp_data, len))
return;

- memcpy(hdev->scan_rsp_data, cp.data, sizeof(cp.data));
+ memcpy(hdev->scan_rsp_data, pdu.data, len);
hdev->scan_rsp_data_len = len;

- cp.handle = instance;
- cp.length = len;
- cp.operation = LE_SET_ADV_DATA_OP_COMPLETE;
- cp.frag_pref = LE_SET_ADV_DATA_NO_FRAG;
+ pdu.cp.handle = instance;
+ pdu.cp.length = len;
+ pdu.cp.operation = LE_SET_ADV_DATA_OP_COMPLETE;
+ pdu.cp.frag_pref = LE_SET_ADV_DATA_NO_FRAG;

- hci_req_add(req, HCI_OP_LE_SET_EXT_SCAN_RSP_DATA, sizeof(cp),
- &cp);
+ hci_req_add(req, HCI_OP_LE_SET_EXT_SCAN_RSP_DATA,
+ sizeof(pdu.cp) + len, &pdu.cp);
} else {
struct hci_cp_le_set_scan_rsp_data cp;

@@ -1843,26 +1846,30 @@ void __hci_req_update_adv_data(struct hci_request *req, u8 instance)
return;

if (ext_adv_capable(hdev)) {
- struct hci_cp_le_set_ext_adv_data cp;
+ struct {
+ struct hci_cp_le_set_ext_adv_data cp;
+ u8 data[HCI_MAX_EXT_AD_LENGTH];
+ } pdu;

- memset(&cp, 0, sizeof(cp));
+ memset(&pdu, 0, sizeof(pdu));

- len = create_instance_adv_data(hdev, instance, cp.data);
+ len = create_instance_adv_data(hdev, instance, pdu.data);

/* There's nothing to do if the data hasn't changed */
if (hdev->adv_data_len == len &&
- memcmp(cp.data, hdev->adv_data, len) == 0)
+ memcmp(pdu.data, hdev->adv_data, len) == 0)
return;

- memcpy(hdev->adv_data, cp.data, sizeof(cp.data));
+ memcpy(hdev->adv_data, pdu.data, len);
hdev->adv_data_len = len;

- cp.length = len;
- cp.handle = instance;
- cp.operation = LE_SET_ADV_DATA_OP_COMPLETE;
- cp.frag_pref = LE_SET_ADV_DATA_NO_FRAG;
+ pdu.cp.length = len;
+ pdu.cp.handle = instance;
+ pdu.cp.operation = LE_SET_ADV_DATA_OP_COMPLETE;
+ pdu.cp.frag_pref = LE_SET_ADV_DATA_NO_FRAG;

- hci_req_add(req, HCI_OP_LE_SET_EXT_ADV_DATA, sizeof(cp), &cp);
+ hci_req_add(req, HCI_OP_LE_SET_EXT_ADV_DATA,
+ sizeof(pdu.cp) + len, &pdu.cp);
} else {
struct hci_cp_le_set_adv_data cp;

--
2.30.2