Commit dd7b8cdd authored by Luiz Augusto von Dentz's avatar Luiz Augusto von Dentz
Browse files

Bluetooth: eir: Fix using strlen with hdev->{dev_name,short_name} 

Both dev_name and short_name are not guaranteed to be NULL terminated so
this instead use strnlen and then attempt to determine if the resulting
string needs to be truncated or not.

Link: https://bugzilla.kernel.org/show_bug.cgi?id=216018


Signed-off-by: default avatarLuiz Augusto von Dentz <luiz.von.dentz@intel.com>
parent a5133fe8

net/bluetooth/eir.c

+26 −15
Original line number Diff line number Diff line
@@ -13,6 +13,20 @@ 


#define PNP_INFO_SVCLASS_ID		0x1200



static u8 eir_append_name(u8 *eir, u16 eir_len, u8 type, u8 *data, u8 data_len)

{

	u8 name[HCI_MAX_SHORT_NAME_LENGTH + 1];



	/* If data is already NULL terminated just pass it directly */

	if (data[data_len - 1] == '\0')

		return eir_append_data(eir, eir_len, type, data, data_len);



	memcpy(name, data, HCI_MAX_SHORT_NAME_LENGTH);

	name[HCI_MAX_SHORT_NAME_LENGTH] = '\0';



	return eir_append_data(eir, eir_len, type, name, sizeof(name));

}



u8 eir_append_local_name(struct hci_dev *hdev, u8 *ptr, u8 ad_len)

{

	size_t short_len;
@@ -23,29 +37,26 @@ u8 eir_append_local_name(struct hci_dev *hdev, u8 *ptr, u8 ad_len) 
		return ad_len;



	/* use complete name if present and fits */

	complete_len = strlen(hdev->dev_name);

	complete_len = strnlen(hdev->dev_name, sizeof(hdev->dev_name));

	if (complete_len && complete_len <= HCI_MAX_SHORT_NAME_LENGTH)

		return eir_append_data(ptr, ad_len, EIR_NAME_COMPLETE,

		return eir_append_name(ptr, ad_len, EIR_NAME_COMPLETE,

				       hdev->dev_name, complete_len + 1);



	/* use short name if present */

	short_len = strlen(hdev->short_name);

	short_len = strnlen(hdev->short_name, sizeof(hdev->short_name));

	if (short_len)

		return eir_append_data(ptr, ad_len, EIR_NAME_SHORT,

				       hdev->short_name, short_len + 1);

		return eir_append_name(ptr, ad_len, EIR_NAME_SHORT,

				       hdev->short_name,

				       short_len == HCI_MAX_SHORT_NAME_LENGTH ?

				       short_len : short_len + 1);



	/* use shortened full name if present, we already know that name

	 * is longer then HCI_MAX_SHORT_NAME_LENGTH

	 */

	if (complete_len) {

		u8 name[HCI_MAX_SHORT_NAME_LENGTH + 1];



		memcpy(name, hdev->dev_name, HCI_MAX_SHORT_NAME_LENGTH);

		name[HCI_MAX_SHORT_NAME_LENGTH] = '\0';



		return eir_append_data(ptr, ad_len, EIR_NAME_SHORT, name,

				       sizeof(name));

	}

	if (complete_len)

		return eir_append_name(ptr, ad_len, EIR_NAME_SHORT,

				       hdev->dev_name,

				       HCI_MAX_SHORT_NAME_LENGTH);



	return ad_len;

}
@@ -181,7 +192,7 @@ void eir_create(struct hci_dev *hdev, u8 *data) 
	u8 *ptr = data;

	size_t name_len;



	name_len = strlen(hdev->dev_name);

	name_len = strnlen(hdev->dev_name, sizeof(hdev->dev_name));



	if (name_len > 0) {

		/* EIR Data type */

net/bluetooth/mgmt.c

+2 −2
Original line number Diff line number Diff line
@@ -1082,11 +1082,11 @@ static u16 append_eir_data_to_buf(struct hci_dev *hdev, u8 *eir) 
		eir_len = eir_append_le16(eir, eir_len, EIR_APPEARANCE,

					  hdev->appearance);



	name_len = strlen(hdev->dev_name);

	name_len = strnlen(hdev->dev_name, sizeof(hdev->dev_name));

	eir_len = eir_append_data(eir, eir_len, EIR_NAME_COMPLETE,

				  hdev->dev_name, name_len);



	name_len = strlen(hdev->short_name);

	name_len = strnlen(hdev->short_name, sizeof(hdev->short_name));

	eir_len = eir_append_data(eir, eir_len, EIR_NAME_SHORT,

				  hdev->short_name, name_len);