Add KASAN support for detecting heap memory safety bugs (buffer
overflows, underflows, use-after-free) at runtime using compiler
instrumentation and shadow memory. Gated behind
CONFIG_IDF_EXPERIMENTAL_FEATURES, with touch points kept to esp_system
and heap so other components stay untouched.
- Core runtime (esp_system/kasan.c, esp_kasan.h): nibble-based shadow
memory in DRAM, poison/unpoison, per-access validation, and __asan_*
stubs; hot-path stubs in IRAM so they stay valid with the flash cache
off. Shadow init runs before heap bring-up.
- Heap integration (heap/heap_kasan*.c): alloc/free hooks add redzones,
a quarantine FIFO, and shadow updates.
- Panic handling: disable checks once at the panic handler entry so
backtrace and stack dumps can read redzones without nested reports.
- Build system: -fsanitize=kernel-address for app code, with HAL, SoC,
esp_rom, SPI flash, esp_hw_support, bootloader_support, FreeRTOS, and
heap internals excluded from instrumentation.
- Test app (tools/test_apps/system/kasan_test): Unity tests for
overflow, underflow, use-after-free, and all sized __asan_* stubs,
with halt and no-halt configurations.
- Docs: document KASAN in the heap memory debugging guide (EN and CN).
Configure the ESP32-H4 ICACHE1_USAGE SRAM ownership bit during app startup
instead of relying on the value left by the bootloader.
Clear ICACHE1_USAGE before external memory/cache setup so single-core apps can
reclaim the ICACHE1 SRAM region as RAM. For multicore apps, set the bit again
when applying multicore cache settings so the region is assigned back to
ICACHE1.
This keeps the app behavior aligned with its own single-core or multicore
configuration even when bootloader and app configs differ.
Wrap MWDT-related code under SOC_WDT_SUPPORTED so targets without a main
watchdog can compile.
Add SOC_RTC_WDT_SUPPORTED for RTC watchdog usage (bootloader, slow-clock
paths) and regenerate Kconfig.soc_caps.in. Bootloader RWDT setup stays
under SOC_RTC_WDT_SUPPORTED; MWDT flashboot teardown stays under
SOC_WDT_SUPPORTED.
ESP_INT_WDT, ESP_TASK_WDT_EN, and BOOTLOADER_WDT_ENABLE depend on
SOC_WDT_SUPPORTED where applicable. Build xt_wdt.c only when
SOC_XT_WDT_SUPPORTED. Provide no-op panic WDT helpers when
SOC_WDT_SUPPORTED is disabled.
Reading from the flash while it is being reconfigured leads to data
corruption and a crash when the reconfiguration code is located in flash.
This is only an issue if a device has a bootloader that runs with 40 MHz
flash and an application flashed via OTA that runs with 80 MHz flash.
If bootloader and application run with the same flash speed, the
reconfiguration is basically a no-op and no data corruption occurs.
Fix reconfiguration by placing the code back into IRAM.
Issue introduced in: 7549d08
Closes: https://github.com/espressif/esp-idf/pull/17905