Commit f6363fde9aae6abbaa3583eb0273f716e96a7811

Sam Lantinga 2023-04-05T11:23:28

Fixed crash if joystick->hwdata != NULL && device->driver == NULL This should never happen, but we're seeing it in the wild, so make sure that we can never call into a NULL device driver. (cherry picked from commit e13b74ccf0b20a20bd4baf1617bdc4f84c13feb7)

diff --git a/src/joystick/hidapi/SDL_hidapijoystick.c b/src/joystick/hidapi/SDL_hidapijoystick.c
index fcbfaa4..d66028d 100644
--- a/src/joystick/hidapi/SDL_hidapijoystick.c
+++ b/src/joystick/hidapi/SDL_hidapijoystick.c
@@ -1432,15 +1432,25 @@ static int HIDAPI_JoystickOpen(SDL_Joystick *joystick, int device_index)
     return 0;
 }
 
-static int HIDAPI_JoystickRumble(SDL_Joystick *joystick, Uint16 low_frequency_rumble, Uint16 high_frequency_rumble)
+static SDL_bool HIDAPI_GetJoystickDevice(SDL_Joystick *joystick, SDL_HIDAPI_Device **device)
 {
-    int result;
-
     SDL_AssertJoysticksLocked();
 
-    if (joystick->hwdata) {
-        SDL_HIDAPI_Device *device = joystick->hwdata->device;
+    if (joystick && joystick->hwdata) {
+        *device = joystick->hwdata->device;
+        if (*device && (*device)->driver) {
+            return SDL_TRUE;
+        }
+    }
+    return SDL_FALSE;
+}
 
+static int HIDAPI_JoystickRumble(SDL_Joystick *joystick, Uint16 low_frequency_rumble, Uint16 high_frequency_rumble)
+{
+    int result;
+    SDL_HIDAPI_Device *device = NULL;
+
+    if (HIDAPI_GetJoystickDevice(joystick, &device)) {
         result = device->driver->RumbleJoystick(device, joystick, low_frequency_rumble, high_frequency_rumble);
     } else {
         result = SDL_SetError("Rumble failed, device disconnected");
@@ -1452,12 +1462,9 @@ static int HIDAPI_JoystickRumble(SDL_Joystick *joystick, Uint16 low_frequency_ru
 static int HIDAPI_JoystickRumbleTriggers(SDL_Joystick *joystick, Uint16 left_rumble, Uint16 right_rumble)
 {
     int result;
+    SDL_HIDAPI_Device *device = NULL;
 
-    SDL_AssertJoysticksLocked();
-
-    if (joystick->hwdata) {
-        SDL_HIDAPI_Device *device = joystick->hwdata->device;
-
+    if (HIDAPI_GetJoystickDevice(joystick, &device)) {
         result = device->driver->RumbleJoystickTriggers(device, joystick, left_rumble, right_rumble);
     } else {
         result = SDL_SetError("Rumble failed, device disconnected");
@@ -1469,12 +1476,9 @@ static int HIDAPI_JoystickRumbleTriggers(SDL_Joystick *joystick, Uint16 left_rum
 static Uint32 HIDAPI_JoystickGetCapabilities(SDL_Joystick *joystick)
 {
     Uint32 result = 0;
+    SDL_HIDAPI_Device *device = NULL;
 
-    SDL_AssertJoysticksLocked();
-
-    if (joystick->hwdata) {
-        SDL_HIDAPI_Device *device = joystick->hwdata->device;
-
+    if (HIDAPI_GetJoystickDevice(joystick, &device)) {
         result = device->driver->GetJoystickCapabilities(device, joystick);
     }
 
@@ -1484,12 +1488,9 @@ static Uint32 HIDAPI_JoystickGetCapabilities(SDL_Joystick *joystick)
 static int HIDAPI_JoystickSetLED(SDL_Joystick *joystick, Uint8 red, Uint8 green, Uint8 blue)
 {
     int result;
+    SDL_HIDAPI_Device *device = NULL;
 
-    SDL_AssertJoysticksLocked();
-
-    if (joystick->hwdata) {
-        SDL_HIDAPI_Device *device = joystick->hwdata->device;
-
+    if (HIDAPI_GetJoystickDevice(joystick, &device)) {
         result = device->driver->SetJoystickLED(device, joystick, red, green, blue);
     } else {
         result = SDL_SetError("SetLED failed, device disconnected");
@@ -1501,12 +1502,9 @@ static int HIDAPI_JoystickSetLED(SDL_Joystick *joystick, Uint8 red, Uint8 green,
 static int HIDAPI_JoystickSendEffect(SDL_Joystick *joystick, const void *data, int size)
 {
     int result;
+    SDL_HIDAPI_Device *device = NULL;
 
-    SDL_AssertJoysticksLocked();
-
-    if (joystick->hwdata) {
-        SDL_HIDAPI_Device *device = joystick->hwdata->device;
-
+    if (HIDAPI_GetJoystickDevice(joystick, &device)) {
         result = device->driver->SendJoystickEffect(device, joystick, data, size);
     } else {
         result = SDL_SetError("SendEffect failed, device disconnected");
@@ -1518,12 +1516,9 @@ static int HIDAPI_JoystickSendEffect(SDL_Joystick *joystick, const void *data, i
 static int HIDAPI_JoystickSetSensorsEnabled(SDL_Joystick *joystick, SDL_bool enabled)
 {
     int result;
+    SDL_HIDAPI_Device *device = NULL;
 
-    SDL_AssertJoysticksLocked();
-
-    if (joystick->hwdata) {
-        SDL_HIDAPI_Device *device = joystick->hwdata->device;
-
+    if (HIDAPI_GetJoystickDevice(joystick, &device)) {
         result = device->driver->SetJoystickSensorsEnabled(device, joystick, enabled);
     } else {
         result = SDL_SetError("SetSensorsEnabled failed, device disconnected");