[PATCH 07/15] Bluetooth: HCI: Use skb_pull_data to parse Extended Inquiry Result event

Luiz Augusto von Dentz
2021-12-01T00:03:28Z

This uses skb_pull_data to check the Extended Inquiry Result events
received have the minimum required length.

Signed-off-by: Luiz Augusto von Dentz <luiz.von.dentz@intel.com>
---
include/net/bluetooth/hci.h | 5 +++++
net/bluetooth/hci_event.c | 20 +++++++++++++++-----
2 files changed, 20 insertions(+), 5 deletions(-)

diff --git a/include/net/bluetooth/hci.h b/include/net/bluetooth/hci.h
index d25afd92a46e..9e721e6efef3 100644
--- a/include/net/bluetooth/hci.h
+++ b/include/net/bluetooth/hci.h
@@ -2273,6 +2273,11 @@ struct extended_inquiry_info {
__u8 data[240];
} __packed;

+struct hci_ev_ext_inquiry_result {
+ __u8 num;
+ struct extended_inquiry_info info[];
+} __packed;
+
#define HCI_EV_KEY_REFRESH_COMPLETE 0x30
struct hci_ev_key_refresh_complete {
__u8 status;
diff --git a/net/bluetooth/hci_event.c b/net/bluetooth/hci_event.c
index 6560dca8c5ce..89c263c1883f 100644
--- a/net/bluetooth/hci_event.c
+++ b/net/bluetooth/hci_event.c
@@ -5186,14 +5186,23 @@ static inline size_t eir_get_length(u8 *eir, size_t eir_len)
static void hci_extended_inquiry_result_evt(struct hci_dev *hdev,
struct sk_buff *skb)
{
+ struct hci_ev_ext_inquiry_result *ev;
struct inquiry_data data;
- struct extended_inquiry_info *info = (void *) (skb->data + 1);
- int num_rsp = *((__u8 *) skb->data);
size_t eir_len;
+ int i;

- BT_DBG("%s num_rsp %d", hdev->name, num_rsp);
+ ev = hci_ev_skb_pull(hdev, skb, HCI_EV_EXTENDED_INQUIRY_RESULT,
+ sizeof(*ev));
+ if (!ev)
+ return;

- if (!num_rsp || skb->len < num_rsp * sizeof(*info) + 1)
+ if (!hci_ev_skb_pull(hdev, skb, HCI_EV_EXTENDED_INQUIRY_RESULT,
+ flex_array_size(ev, info, ev->num)))
+ return;
+
+ BT_DBG("%s num %d", hdev->name, ev->num);
+
+ if (!ev->num)
return;

if (hci_dev_test_flag(hdev, HCI_PERIODIC_INQ))
@@ -5201,7 +5210,8 @@ static void hci_extended_inquiry_result_evt(struct hci_dev *hdev,

hci_dev_lock(hdev);

- for (; num_rsp; num_rsp--, info++) {
+ for (i = 0; i < ev->num; i++) {
+ struct extended_inquiry_info *info = &ev->info[i];
u32 flags;
bool name_known;

--
2.33.1