Bluetooth: Unify advertising instance flags check

This unifies max length and TLV validity checks.

Signed-off-by: Szymon Janc <szymon.janc@codecoup.pl>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>

diff --git a/net/bluetooth/mgmt.c b/net/bluetooth/mgmt.c
index 97f70b7..c96b0ad 100644 (file)
--- a/net/bluetooth/mgmt.c
+++ b/net/bluetooth/mgmt.c
@@ -6005,34 +6005,59 @@ static int read_adv_features(struct sock *sk, struct hci_dev *hdev,
        return err;
 }
 
-static bool tlv_data_is_valid(u32 adv_flags, u8 *data, u8 len, bool is_adv_data)
+static u8 tlv_data_max_len(u32 adv_flags, bool is_adv_data)
 {
        u8 max_len = HCI_MAX_AD_LENGTH;
-       int i, cur_len;
-       bool flags_managed = false;
-       bool tx_power_managed = false;
 
        if (is_adv_data) {
                if (adv_flags & (MGMT_ADV_FLAG_DISCOV |
                                 MGMT_ADV_FLAG_LIMITED_DISCOV |
-                                MGMT_ADV_FLAG_MANAGED_FLAGS)) {
-                       flags_managed = true;
+                                MGMT_ADV_FLAG_MANAGED_FLAGS))
                        max_len -= 3;
-               }
 
-               if (adv_flags & MGMT_ADV_FLAG_TX_POWER) {
-                       tx_power_managed = true;
+               if (adv_flags & MGMT_ADV_FLAG_TX_POWER)
                        max_len -= 3;
-               }
        } else {
                /* at least 1 byte of name should fit in */
                if (adv_flags & MGMT_ADV_FLAG_LOCAL_NAME)
                        max_len -= 3;
 
-               if (adv_flags & MGMT_ADV_FLAG_APPEARANCE)
+               if (adv_flags & (MGMT_ADV_FLAG_APPEARANCE))
                        max_len -= 4;
        }
 
+       return max_len;
+}
+
+static bool flags_managed(u32 adv_flags)
+{
+       return adv_flags & (MGMT_ADV_FLAG_DISCOV |
+                           MGMT_ADV_FLAG_LIMITED_DISCOV |
+                           MGMT_ADV_FLAG_MANAGED_FLAGS);
+}
+
+static bool tx_power_managed(u32 adv_flags)
+{
+       return adv_flags & MGMT_ADV_FLAG_TX_POWER;
+}
+
+static bool name_managed(u32 adv_flags)
+{
+       return adv_flags & MGMT_ADV_FLAG_LOCAL_NAME;
+}
+
+static bool appearance_managed(u32 adv_flags)
+{
+       return adv_flags & MGMT_ADV_FLAG_APPEARANCE;
+}
+
+static bool tlv_data_is_valid(u32 adv_flags, u8 *data, u8 len, bool is_adv_data)
+{
+       int i, cur_len;
+       u8 max_len;
+
+       max_len = tlv_data_max_len(adv_flags, is_adv_data);
+
        if (len > max_len)
                return false;
 
@@ -6040,10 +6065,20 @@ static bool tlv_data_is_valid(u32 adv_flags, u8 *data, u8 len, bool is_adv_data)
        for (i = 0, cur_len = 0; i < len; i += (cur_len + 1)) {
                cur_len = data[i];
 
-               if (flags_managed && data[i + 1] == EIR_FLAGS)
+               if (data[i + 1] == EIR_FLAGS && flags_managed(adv_flags))
+                       return false;
+
+               if (data[i + 1] == EIR_TX_POWER && tx_power_managed(adv_flags))
+                       return false;
+
+               if (data[i + 1] == EIR_NAME_COMPLETE && name_managed(adv_flags))
+                       return false;
+
+               if (data[i + 1] == EIR_NAME_SHORT && name_managed(adv_flags))
                        return false;
 
-               if (tx_power_managed && data[i + 1] == EIR_TX_POWER)
+               if (data[i + 1] == EIR_APPEARANCE &&
+                   appearance_managed(adv_flags))
                        return false;
 
                /* If the current field length would exceed the total data
@@ -6351,30 +6386,6 @@ unlock:
        return err;
 }
 
-static u8 tlv_data_max_len(u32 adv_flags, bool is_adv_data)
-{
-       u8 max_len = HCI_MAX_AD_LENGTH;
-
-       if (is_adv_data) {
-               if (adv_flags & (MGMT_ADV_FLAG_DISCOV |
-                                MGMT_ADV_FLAG_LIMITED_DISCOV |
-                                MGMT_ADV_FLAG_MANAGED_FLAGS))
-                       max_len -= 3;
-
-               if (adv_flags & MGMT_ADV_FLAG_TX_POWER)
-                       max_len -= 3;
-       } else {
-               /* at least 1 byte of name should fit in */
-               if (adv_flags & MGMT_ADV_FLAG_LOCAL_NAME)
-                       max_len -= 3;
-
-               if (adv_flags & (MGMT_ADV_FLAG_APPEARANCE))
-                       max_len -= 4;
-       }
-
-       return max_len;
-}
-
 static int get_adv_size_info(struct sock *sk, struct hci_dev *hdev,
                             void *data, u16 data_len)
 {