[Bluetooth]: Workaround for inquiry results with RSSI and page scan mode

This patch implements a workaround for buggy Bluetooth 1.2 devices from
Silicon Wave. Their inquiry results with RSSI contain the page scan mode
field. This field was removed in the final Bluetooth 1.2 specification.

Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
Signed-off-by: David S. Miller <davem@davemloft.net>

1 files changed, 42 insertions, 13 deletions

diff --git a/net/bluetooth/hci_event.c b/net/bluetooth/hci_event.c
index 46367bd129c3..632f7a9c2bcb 100644
--- a/net/bluetooth/hci_event.c
+++ b/net/bluetooth/hci_event.c
@@ -484,14 +484,18 @@ static inline void hci_inquiry_complete_evt(struct hci_dev *hdev, struct sk_buff
 /* Inquiry Result */
 static inline void hci_inquiry_result_evt(struct hci_dev *hdev, struct sk_buff *skb)
 {
+        struct inquiry_data data;
         struct inquiry_info *info = (struct inquiry_info *) (skb->data + 1);
         int num_rsp = *((__u8 *) skb->data);
 
         BT_DBG("%s num_rsp %d", hdev->name, num_rsp);
 
+        if (!num_rsp)
+                return;
+
         hci_dev_lock(hdev);
+
         for (; num_rsp; num_rsp--) {
-                struct inquiry_data data;
                 bacpy(&data.bdaddr, &info->bdaddr);
                 data.pscan_rep_mode     = info->pscan_rep_mode;
                 data.pscan_period_mode  = info->pscan_period_mode;
@@ -502,30 +506,55 @@ static inline void hci_inquiry_result_evt(struct hci_dev *hdev, struct sk_buff *
                 info++;
                 hci_inquiry_cache_update(hdev, &data);
         }
+
         hci_dev_unlock(hdev);
 }
 
 /* Inquiry Result With RSSI */
 static inline void hci_inquiry_result_with_rssi_evt(struct hci_dev *hdev, struct sk_buff *skb)
 {
-        struct inquiry_info_with_rssi *info = (struct inquiry_info_with_rssi *) (skb->data + 1);
+        struct inquiry_data data;
         int num_rsp = *((__u8 *) skb->data);
 
         BT_DBG("%s num_rsp %d", hdev->name, num_rsp);
 
+        if (!num_rsp)
+                return;
+
         hci_dev_lock(hdev);
-        for (; num_rsp; num_rsp--) {
-                struct inquiry_data data;
-                bacpy(&data.bdaddr, &info->bdaddr);
-                data.pscan_rep_mode     = info->pscan_rep_mode;
-                data.pscan_period_mode  = info->pscan_period_mode;
-                data.pscan_mode         = 0x00;
-                memcpy(data.dev_class, info->dev_class, 3);
-                data.clock_offset       = info->clock_offset;
-                data.rssi               = info->rssi;
-                info++;
-                hci_inquiry_cache_update(hdev, &data);
+
+        if ((skb->len - 1) / num_rsp != sizeof(struct inquiry_info_with_rssi)) {
+                struct inquiry_info_with_rssi_and_pscan_mode *info =
+                        (struct inquiry_info_with_rssi_and_pscan_mode *) (skb->data + 1);
+
+                for (; num_rsp; num_rsp--) {
+                        bacpy(&data.bdaddr, &info->bdaddr);
+                        data.pscan_rep_mode     = info->pscan_rep_mode;
+                        data.pscan_period_mode  = info->pscan_period_mode;
+                        data.pscan_mode         = info->pscan_mode;
+                        memcpy(data.dev_class, info->dev_class, 3);
+                        data.clock_offset       = info->clock_offset;
+                        data.rssi               = info->rssi;
+                        info++;
+                        hci_inquiry_cache_update(hdev, &data);
+                }
+        } else {
+                struct inquiry_info_with_rssi *info =
+                        (struct inquiry_info_with_rssi *) (skb->data + 1);
+
+                for (; num_rsp; num_rsp--) {
+                        bacpy(&data.bdaddr, &info->bdaddr);
+                        data.pscan_rep_mode     = info->pscan_rep_mode;
+                        data.pscan_period_mode  = info->pscan_period_mode;
+                        data.pscan_mode         = 0x00;
+                        memcpy(data.dev_class, info->dev_class, 3);
+                        data.clock_offset       = info->clock_offset;
+                        data.rssi               = info->rssi;
+                        info++;
+                        hci_inquiry_cache_update(hdev, &data);
+                }
         }
+
         hci_dev_unlock(hdev);
 }