scott/InfiniTime
1
0
Fork 0
Code Issues Pull requests Actions Packages Projects Releases 1 Wiki Activity

Fix buffer overflow opportunities in AlertNotificationService & AlertNotificationClient.

Browse source
This commit is contained in:
JF 2020-06-28 11:59:14 +02:00
parent 4f9adb2372
commit 89e7033830
4 changed files with 43 additions and 27 deletions
Show stats Download patch file Download diff file Expand all files Collapse all files

25
src/Components/Ble/AlertNotificationClient.cpp
View file

@ -105,14 +105,25 @@ int AlertNotificationClient::OnDescriptorDiscoveryEventCallback(uint16_t connect
void AlertNotificationClient::OnNotification(ble_gap_event *event) {
if(event->notify_rx.attr_handle == newAlertHandle) {
size_t notifSize = OS_MBUF_PKTLEN(event->notify_rx.om);
uint8_t data[notifSize + 1];
data[notifSize] = '\0';
os_mbuf_copydata(event->notify_rx.om, 0, notifSize, data);
char *s = (char *) &data[2];
NRF_LOG_INFO("DATA : %s", s);
// TODO implement this with more memory safety (and constexpr)
static const size_t maxBufferSize{21};
static const size_t maxMessageSize{18};
size_t bufferSize = min(OS_MBUF_PKTLEN(event->notify_rx.om), maxBufferSize);
notificationManager.Push(Pinetime::Controllers::NotificationManager::Categories::SimpleAlert, s, notifSize + 1);
uint8_t data[bufferSize];
os_mbuf_copydata(event->notify_rx.om, 0, bufferSize, data);
char *s = (char *) &data[3];
auto messageSize = min(maxMessageSize, (bufferSize-3));
for (int i = 0; i < messageSize-1; i++) {
if (s[i] == 0x00) {
s[i] = 0x0A;
}
}
s[messageSize-1] = '\0';
notificationManager.Push(Pinetime::Controllers::NotificationManager::Categories::SimpleAlert, s, messageSize);
systemTask.PushMessage(Pinetime::System::SystemTask::Messages::OnNewNotification);
}
}

26
src/Components/Ble/AlertNotificationService.cpp
View file

@ -4,6 +4,7 @@
#include <SystemTask/SystemTask.h>
#include "AlertNotificationService.h"
#include <cstring>
using namespace Pinetime::Controllers;
@ -55,22 +56,25 @@ int AlertNotificationService::OnAlert(uint16_t conn_handle, uint16_t attr_handle
struct ble_gatt_access_ctxt *ctxt) {
if (ctxt->op == BLE_GATT_ACCESS_OP_WRITE_CHR) {
size_t notifSize = OS_MBUF_PKTLEN(ctxt->om);
uint8_t data[notifSize + 1];
data[notifSize] = '\0';
os_mbuf_copydata(ctxt->om, 0, notifSize, data);
char *s = (char *) &data[3];
NRF_LOG_INFO("DATA : %s", s);
// TODO implement this with more memory safety (and constexpr)
static const size_t maxBufferSize{21};
static const size_t maxMessageSize{18};
size_t bufferSize = min(OS_MBUF_PKTLEN(ctxt->om), maxBufferSize);
for(int i = 0; i <= notifSize; i++)
{
if(s[i] == 0x00)
{
uint8_t data[bufferSize];
os_mbuf_copydata(ctxt->om, 0, bufferSize, data);
char *s = (char *) &data[3];
auto messageSize = min(maxMessageSize, (bufferSize-3));
for (int i = 0; i < messageSize-1; i++) {
if (s[i] == 0x00) {
s[i] = 0x0A;
}
}
s[messageSize-1] = '\0';
m_notificationManager.Push(Pinetime::Controllers::NotificationManager::Categories::SimpleAlert, s, notifSize + 1);
m_notificationManager.Push(Pinetime::Controllers::NotificationManager::Categories::SimpleAlert, s, messageSize);
m_systemTask.PushMessage(Pinetime::System::SystemTask::Messages::OnNewNotification);
}
return 0;

7
src/Components/Ble/NotificationManager.cpp
View file

@ -4,11 +4,12 @@
using namespace Pinetime::Controllers;
void NotificationManager::Push(Pinetime::Controllers::NotificationManager::Categories category,
const char *message, uint8_t messageSize) {
const char *message, uint8_t currentMessageSize) {
// TODO handle edge cases on read/write index
auto checkedSize = std::min(currentMessageSize, uint8_t{18});
auto& notif = notifications[writeIndex];
std::memcpy(notif.message.data(), message, messageSize);
notif.message[messageSize] = '\0';
std::memcpy(notif.message.data(), message, checkedSize);
notif.message[checkedSize] = '\0';
notif.category = category;
writeIndex = (writeIndex + 1 < TotalNbNotifications) ? writeIndex + 1 : 0;

4
src/Components/Ble/NotificationManager.h
View file

@ -7,10 +7,10 @@ namespace Pinetime {
class NotificationManager {
public:
enum class Categories {Unknown, SimpleAlert, Email, News, IncomingCall, MissedCall, Sms, VoiceMail, Schedule, HighProriotyAlert, InstantMessage };
static constexpr uint8_t MessageSize = 18;
static constexpr uint8_t MessageSize{18};
struct Notification {
std::array<char, MessageSize> message;
std::array<char, MessageSize+1> message;
Categories category = Categories::Unknown;
};