From: Luiz Augusto von Dentz <[email protected]>
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: Luiz Augusto von Dentz <[email protected]>
---
net/bluetooth/eir.c | 41 ++++++++++++++++++++++++++---------------
1 file changed, 26 insertions(+), 15 deletions(-)
diff --git a/net/bluetooth/eir.c b/net/bluetooth/eir.c
index 7e930f77ecab..4171edee88e4 100644
--- a/net/bluetooth/eir.c
+++ b/net/bluetooth/eir.c
@@ -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;
}
@@ -168,7 +179,7 @@ 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 */
--
2.35.1