Skip to content

Mask MPU region base addresses when writing to MPU_RBAR to fix potential kernel region setting override #1473

New issue

Have a question about this project? Sign up for a free GitHub account to open an issue and contact its maintainers and the community.

Sign up for GitHub

By clicking “Sign up for GitHub”, you agree to our terms of service and privacy statement. We’ll occasionally send you account related emails.

Already on GitHub? Sign in to your account

Open
CocoDico78 wants to merge 1 commit into
base: main
Choose a base branch
from
+8 −7
Open

Mask MPU region base addresses when writing to MPU_RBAR to fix potential kernel region setting override #1473

Changes from all commits
Commits
Show all changes
1 commit
Select commit
File filter

Filter by extension

Filter by extension
Conversations
Failed to load comments.
Loading
Jump to
Jump to file
Failed to load files.
Loading
Diff view
Diff view
15 changes: 8 additions & 7 deletions portable/GCC/ARM_CM3_MPU/port.c
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -95,6 +95,7 @@ typedef void ( * portISR_t )( void );
#define portMPU_REGION_ENABLE ( 0x01UL )
#define portPERIPHERALS_START_ADDRESS 0x40000000UL
#define portPERIPHERALS_END_ADDRESS 0x5FFFFFFFUL
#define portMPU_RBAR_ADDRESS_MASK 0xFFFFFFE0

/* Constants required to access and manipulate the SysTick. */
#define portNVIC_SYSTICK_INT ( 0x00000002UL )
Expand Down Expand Up @@ -1136,7 +1137,7 @@ static void prvSetupMPU( void )
if( portMPU_TYPE_REG == portEXPECTED_MPU_TYPE_VALUE )
{
/* First setup the unprivileged flash for unprivileged read only access. */
portMPU_REGION_BASE_ADDRESS_REG = ( ( uint32_t ) __FLASH_segment_start__ ) | /* Base address. */
portMPU_REGION_BASE_ADDRESS_REG = ( ( ( uint32_t ) __FLASH_segment_start__ ) & portMPU_RBAR_ADDRESS_MASK ) | /* Base address. */
( portMPU_REGION_VALID ) |
( portUNPRIVILEGED_FLASH_REGION );

Expand All @@ -1147,7 +1148,7 @@ static void prvSetupMPU( void )

/* Setup the privileged flash for privileged only access. This is where
* the kernel code is * placed. */
portMPU_REGION_BASE_ADDRESS_REG = ( ( uint32_t ) __privileged_functions_start__ ) | /* Base address. */
portMPU_REGION_BASE_ADDRESS_REG = ( ( ( uint32_t ) __privileged_functions_start__ ) & portMPU_RBAR_ADDRESS_MASK ) | /* Base address. */
( portMPU_REGION_VALID ) |
( portPRIVILEGED_FLASH_REGION );

Expand All @@ -1158,7 +1159,7 @@ static void prvSetupMPU( void )

/* Setup the privileged data RAM region. This is where the kernel data
* is placed. */
portMPU_REGION_BASE_ADDRESS_REG = ( ( uint32_t ) __privileged_data_start__ ) | /* Base address. */
portMPU_REGION_BASE_ADDRESS_REG = ( ( ( uint32_t ) __privileged_data_start__ ) & portMPU_RBAR_ADDRESS_MASK ) | /* Base address. */
( portMPU_REGION_VALID ) |
( portPRIVILEGED_RAM_REGION );

Expand All @@ -1170,7 +1171,7 @@ static void prvSetupMPU( void )

/* By default allow everything to access the general peripherals. The
* system peripherals and registers are protected. */
portMPU_REGION_BASE_ADDRESS_REG = ( portPERIPHERALS_START_ADDRESS ) |
portMPU_REGION_BASE_ADDRESS_REG = ( portPERIPHERALS_START_ADDRESS & portMPU_RBAR_ADDRESS_MASK ) |
( portMPU_REGION_VALID ) |
( portGENERAL_PERIPHERALS_REGION );

Expand Down Expand Up @@ -1280,7 +1281,7 @@ void vPortStoreTaskMPUSettings( xMPU_SETTINGS * xMPUSettings,
{
/* No MPU regions are specified so allow access to all RAM. */
xMPUSettings->xRegion[ 0 ].ulRegionBaseAddress =
( ( uint32_t ) __SRAM_segment_start__ ) | /* Base address. */
( ( ( uint32_t ) __SRAM_segment_start__ ) & portMPU_RBAR_ADDRESS_MASK ) | /* Base address. */
( portMPU_REGION_VALID ) |
( portSTACK_REGION ); /* Region number. */

Expand Down Expand Up @@ -1316,7 +1317,7 @@ void vPortStoreTaskMPUSettings( xMPU_SETTINGS * xMPUSettings,
{
/* Define the region that allows access to the stack. */
xMPUSettings->xRegion[ 0 ].ulRegionBaseAddress =
( ( uint32_t ) pxBottomOfStack ) |
( ( ( uint32_t ) pxBottomOfStack ) & portMPU_RBAR_ADDRESS_MASK ) |
( portMPU_REGION_VALID ) |
( portSTACK_REGION ); /* Region number. */

Expand All @@ -1343,7 +1344,7 @@ void vPortStoreTaskMPUSettings( xMPU_SETTINGS * xMPUSettings,
* xRegions into the CM3 specific MPU settings that are then
* stored in xMPUSettings. */
xMPUSettings->xRegion[ ul ].ulRegionBaseAddress =
( ( uint32_t ) xRegions[ lIndex ].pvBaseAddress ) |
( ( ( uint32_t ) xRegions[ lIndex ].pvBaseAddress ) & portMPU_RBAR_ADDRESS_MASK ) |
( portMPU_REGION_VALID ) |
( ul - 1UL ); /* Region number. */

Expand Down
Loading