How did you manage to call SE_APP_ValidateFw() from within the UserApp? I am trying to run SBSFU with ENABLE_IMAGE_STATE_HANDLING, but the SE_APP_ValidateFw() function will reset the STM32L4A6 as the function is not in the expected memory boundary. Are you calling the SE_APP_ValidateFw() from the UserApp in the SBSFU code?
The failing part is in the function
/*Secure Engine Call*/
e_ret_status = (*SE_CallGatePtr)(SE_APP_VALIDATE_FW, peSE_Status, primask_bit, SlotNumber);
and this calls the:
SE_ErrorStatus SE_CallGate(SE_FunctionIDTypeDef eID, SE_StatusTypeDef * const peSE_Status, uint32_t PrimaskParam, ...)
{
SE_ErrorStatus e_ret_status;
va_list arguments;
#if defined(__GNUC__)
register unsigned lr asm("lr");
uint32_t LR = lr;
#else
uint32_t LR;
#endif /* __GNUC__ */
/* Enter the protected area */
ENTER_PROTECTED_AREA();
/*
* Warning : It is mandatory to call NVIC_SystemReset() in case of error
* instead of return(SE_ERROR) to avoid any attempt of attack by modifying
* the call stack (LR) in order to execute code inside secure enclave
*/
/* Check the Callgate was called only from SE Interface */
#if defined(__ICCARM__) || defined (__CC_ARM)
LR = __get_LR();
#endif /* __ICCARM__ || __CC_ARM */
IS_CALLER_SE_IF();
the IS_CALLER_SE_IF is
#define IS_CALLER_SE_IF() \
do{ \
if (LR< SE_IF_REGION_ROM_START){\
NVIC_SystemReset();}\
if (LR> SE_IF_REGION_ROM_END){\
NVIC_SystemReset();}\
}while(0)
and obviously, if the SE_APP_ValidateFw() function is in the UserApp flash space, the second IF will trigger a reset.
So, my question is, how did you avoid this? I'm on STM32CubeIde. Too bad STM tries its best not to provide working examples on STM32CubeIde.
