flipperzero-firmware/firmware/targets/f7/furi_hal/furi_hal_mpu.c
SG eed4296890
MPU Hal (#1492)
* Furi HAL: memory protection unit
* Core: prohibit NULL dereferencing, even for reads.
* Applications: fix NULL dereference
* Core: stack protection by MPU
* MPU: stack region alignment
* Apps: fix null pointer dereferences
* Threads: fix non-null arg check
* Desktop settings: fix null pointer dereference
* Core: documented null-check hack
* Fix null dereference issues
* Apps: args check
* Core: naming fixes
* format code
* Core: remove NONNULL specifier
* FurHal: move MPU initialization to begining, fix enum naming

Co-authored-by: あく <alleteam@gmail.com>
2022-08-04 00:47:10 +09:00

66 lines
2.0 KiB
C

#include <furi_hal_mpu.h>
#include <stm32wbxx_ll_cortex.h>
#define FURI_HAL_MPU_ATTRIBUTES \
(LL_MPU_ACCESS_BUFFERABLE | LL_MPU_ACCESS_CACHEABLE | LL_MPU_ACCESS_SHAREABLE | \
LL_MPU_TEX_LEVEL1 | LL_MPU_INSTRUCTION_ACCESS_ENABLE)
#define FURI_HAL_MPU_STACK_PROTECT_REGION FuriHalMPURegionSize32B
void furi_hal_mpu_init() {
furi_hal_mpu_enable();
// NULL pointer dereference protection
furi_hal_mpu_protect_no_access(FuriHalMpuRegionNULL, 0x00, FuriHalMPURegionSize1MB);
}
void furi_hal_mpu_enable() {
LL_MPU_Enable(LL_MPU_CTRL_PRIVILEGED_DEFAULT);
}
void furi_hal_mpu_disable() {
LL_MPU_Disable();
}
void furi_hal_mpu_protect_no_access(
FuriHalMpuRegion region,
uint32_t address,
FuriHalMPURegionSize size) {
uint32_t size_ll = size;
size_ll = size_ll << MPU_RASR_SIZE_Pos;
furi_hal_mpu_disable();
LL_MPU_ConfigRegion(
region, 0x00, address, FURI_HAL_MPU_ATTRIBUTES | LL_MPU_REGION_NO_ACCESS | size_ll);
furi_hal_mpu_enable();
}
void furi_hal_mpu_protect_read_only(
FuriHalMpuRegion region,
uint32_t address,
FuriHalMPURegionSize size) {
uint32_t size_ll = size;
size_ll = size_ll << MPU_RASR_SIZE_Pos;
furi_hal_mpu_disable();
LL_MPU_ConfigRegion(
region, 0x00, address, FURI_HAL_MPU_ATTRIBUTES | LL_MPU_REGION_PRIV_RO_URO | size_ll);
furi_hal_mpu_enable();
}
void furi_hal_mpu_protect_disable(FuriHalMpuRegion region) {
furi_hal_mpu_disable();
LL_MPU_DisableRegion(region);
furi_hal_mpu_enable();
}
void furi_hal_mpu_set_stack_protection(uint32_t* stack) {
// Protection area address must be aligned to region size
uint32_t stack_ptr = (uint32_t)stack;
uint32_t mask = ((1 << (FURI_HAL_MPU_STACK_PROTECT_REGION + 2)) - 1);
stack_ptr &= ~mask;
if(stack_ptr < (uint32_t)stack) stack_ptr += (mask + 1);
furi_hal_mpu_protect_read_only(
FuriHalMpuRegionStack, stack_ptr, FURI_HAL_MPU_STACK_PROTECT_REGION);
}