[v1] Bluetooth: msft: fix null pointer deref on msft_monitor_device_evt

[PATCH] Bluetooth: msft: fix null pointer deref on msft_monitor_device_evt

Posted by Soenke Huster 4 years, 5 months ago

msft_find_handle_data returns NULL if it can't find the handle.
Therefore, handle_data must be checked, otherwise a null pointer
is dereferenced.

Signed-off-by: Soenke Huster <soenke.huster@eknoes.de>
---
 net/bluetooth/msft.c | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/net/bluetooth/msft.c b/net/bluetooth/msft.c
index 484540855863..d2cf92e834f7 100644
--- a/net/bluetooth/msft.c
+++ b/net/bluetooth/msft.c
@@ -705,6 +705,9 @@ static void msft_monitor_device_evt(struct hci_dev *hdev, struct sk_buff *skb)
 
 	handle_data = msft_find_handle_data(hdev, ev->monitor_handle, false);
 
+	if (!handle_data)
+		return;
+
 	switch (ev->addr_type) {
 	case ADDR_LE_DEV_PUBLIC:
 		addr_type = BDADDR_LE_PUBLIC;
-- 
2.34.1

Re: [PATCH] Bluetooth: msft: fix null pointer deref on msft_monitor_device_evt

Posted by Marcel Holtmann 4 years, 5 months ago

Hi Soenke,

> msft_find_handle_data returns NULL if it can't find the handle.
> Therefore, handle_data must be checked, otherwise a null pointer
> is dereferenced.
> 
> Signed-off-by: Soenke Huster <soenke.huster@eknoes.de>
> ---
> net/bluetooth/msft.c | 3 +++
> 1 file changed, 3 insertions(+)
> 
> diff --git a/net/bluetooth/msft.c b/net/bluetooth/msft.c
> index 484540855863..d2cf92e834f7 100644
> --- a/net/bluetooth/msft.c
> +++ b/net/bluetooth/msft.c
> @@ -705,6 +705,9 @@ static void msft_monitor_device_evt(struct hci_dev *hdev, struct sk_buff *skb)
> 
> 	handle_data = msft_find_handle_data(hdev, ev->monitor_handle, false);
> 

scrap this empty line. The check can got right after the assignment.

> +	if (!handle_data)
> +		return;
> +
> 	switch (ev->addr_type) {
> 	case ADDR_LE_DEV_PUBLIC:
> 		addr_type = BDADDR_LE_PUBLIC;

Regards

Marcel