[PATCH 04/15] Bluetooth: HCI: Use skb_pull_data to parse Number of Complete Packets event

Luiz Augusto von Dentz
2021-12-01T00:03:23Z

This uses skb_pull_data to check the Number of Complete Packets events
received have the minimum required length.

Signed-off-by: Luiz Augusto von Dentz <luiz.von.dentz@intel.com>
---
include/net/bluetooth/hci.h | 2 +-
net/bluetooth/hci_event.c | 20 +++++++++++---------
2 files changed, 12 insertions(+), 10 deletions(-)

diff --git a/include/net/bluetooth/hci.h b/include/net/bluetooth/hci.h
index ba89b078ceb5..3f57fd677b67 100644
--- a/include/net/bluetooth/hci.h
+++ b/include/net/bluetooth/hci.h
@@ -2139,7 +2139,7 @@ struct hci_comp_pkts_info {
} __packed;

struct hci_ev_num_comp_pkts {
- __u8 num_hndl;
+ __u8 num;
struct hci_comp_pkts_info handles[];
} __packed;

diff --git a/net/bluetooth/hci_event.c b/net/bluetooth/hci_event.c
index 09d7d997c4b1..b27a4ad647ca 100644
--- a/net/bluetooth/hci_event.c
+++ b/net/bluetooth/hci_event.c
@@ -4465,23 +4465,25 @@ static void hci_role_change_evt(struct hci_dev *hdev, struct sk_buff *skb)

static void hci_num_comp_pkts_evt(struct hci_dev *hdev, struct sk_buff *skb)
{
- struct hci_ev_num_comp_pkts *ev = (void *) skb->data;
+ struct hci_ev_num_comp_pkts *ev;
int i;

- if (hdev->flow_ctl_mode != HCI_FLOW_CTL_MODE_PACKET_BASED) {
- bt_dev_err(hdev, "wrong event for mode %d", hdev->flow_ctl_mode);
+ ev = hci_ev_skb_pull(hdev, skb, HCI_EV_NUM_COMP_PKTS, sizeof(*ev));
+ if (!ev)
return;
- }

- if (skb->len < sizeof(*ev) ||
- skb->len < struct_size(ev, handles, ev->num_hndl)) {
- BT_DBG("%s bad parameters", hdev->name);
+ if (!hci_ev_skb_pull(hdev, skb, HCI_EV_NUM_COMP_PKTS,
+ flex_array_size(ev, handles, ev->num)))
+ return;
+
+ if (hdev->flow_ctl_mode != HCI_FLOW_CTL_MODE_PACKET_BASED) {
+ bt_dev_err(hdev, "wrong event for mode %d", hdev->flow_ctl_mode);
return;
}

- BT_DBG("%s num_hndl %d", hdev->name, ev->num_hndl);
+ BT_DBG("%s num %d", hdev->name, ev->num);

- for (i = 0; i < ev->num_hndl; i++) {
+ for (i = 0; i < ev->num; i++) {
struct hci_comp_pkts_info *info = &ev->handles[i];
struct hci_conn *conn;
__u16 handle, count;
--
2.33.1