esp-idf/tools/test_apps/system/memprot/main/esp32c3/test_panic.c
2021-04-12 13:44:11 +10:00

53 lines
2.0 KiB
C

// Copyright 2015-2016 Espressif Systems (Shanghai) PTE LTD
//
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
// http://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.
#include "riscv/rvruntime-frames.h"
#include "esp_private/panic_internal.h"
#define MCAUSE_ILLEGAL_INSTRUCTION 2
extern void esp_panic_handler(panic_info_t *info);
volatile bool g_override_illegal_instruction = false;
void __real_esp_panic_handler(panic_info_t *info);
void return_from_panic_handler(RvExcFrame *frm) __attribute__((noreturn));
/* Memprot test specific IllegalInstruction exception handler:
* when testing the protection against a code execution, sample code
* is being injected into various memory regions which produces
* Illegal instruction on execution attempt. Such a result is expected
* but it causes system reboot in the standard panic handler.
* The following variant of panic handling simply returns back to the
* next instruction and continues normal execution.
*
* NOTE: if Illegal instruction comes from a different source than the testing code
* the behavior is undefined
* */
void __wrap_esp_panic_handler(panic_info_t *info)
{
RvExcFrame *frm = (RvExcFrame *)info->frame;
if ( frm->mcause == MCAUSE_ILLEGAL_INSTRUCTION && g_override_illegal_instruction == true ) {
/* Return from exception to the return address that called the faulting function.
*/
frm->mepc = frm->ra;
/* Restore the CPU state and return from the exception.
*/
return_from_panic_handler(frm);
} else {
__real_esp_panic_handler(info);
}
}