2021-04-16 22:07:54

by Luiz Augusto von Dentz

[permalink] [raw]
Subject: [PATCH 04/10] Bluetooth: HCI: Use skb_pull to parse Inquiry Result event

From: Luiz Augusto von Dentz <[email protected]>

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

Signed-off-by: Luiz Augusto von Dentz <[email protected]>
---
include/net/bluetooth/hci.h | 5 +++++
net/bluetooth/hci_event.c | 19 ++++++++++++++-----
2 files changed, 19 insertions(+), 5 deletions(-)

diff --git a/include/net/bluetooth/hci.h b/include/net/bluetooth/hci.h
index 9251ae3a2ce0..b65205b4d830 100644
--- a/include/net/bluetooth/hci.h
+++ b/include/net/bluetooth/hci.h
@@ -1910,6 +1910,11 @@ struct inquiry_info {
__le16 clock_offset;
} __packed;

+struct hci_ev_inquiry_result {
+ __u8 num;
+ struct inquiry_info info[];
+};
+
#define HCI_EV_CONN_COMPLETE 0x03
struct hci_ev_conn_complete {
__u8 status;
diff --git a/net/bluetooth/hci_event.c b/net/bluetooth/hci_event.c
index 65b7194ae1ba..8fa11e99b1cb 100644
--- a/net/bluetooth/hci_event.c
+++ b/net/bluetooth/hci_event.c
@@ -2991,13 +2991,21 @@ static void hci_inquiry_complete_evt(struct hci_dev *hdev, struct sk_buff *skb)

static void hci_inquiry_result_evt(struct hci_dev *hdev, struct sk_buff *skb)
{
+ struct hci_ev_inquiry_result *ev;
struct inquiry_data data;
- struct inquiry_info *info = (void *) (skb->data + 1);
- int num_rsp = *((__u8 *) skb->data);
+ int i;

- BT_DBG("%s num_rsp %d", hdev->name, num_rsp);
+ ev = hci_ev_skb_pull(hdev, skb, HCI_EV_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_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))
@@ -3005,7 +3013,8 @@ static void hci_inquiry_result_evt(struct hci_dev *hdev, struct sk_buff *skb)

hci_dev_lock(hdev);

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

bacpy(&data.bdaddr, &info->bdaddr);
--
2.30.2