ea9c26f524
ARMv7-M allows overlapping MPU regions. When 2 MPU regions overlap, the MPU configuration of the higher numbered MPU region is applied. For example, if a memory area is covered by 2 MPU regions 0 and 1, the memory permissions for MPU region 1 are applied. We use 5 MPU regions for kernel code and kernel data protections and leave the remaining for the application writer. We were using lowest numbered MPU regions (0-4) for kernel protections and leaving the remaining for the application writer. The application writer could configure those higher numbered MPU regions to override kernel protections. This commit changes the code to use highest numbered MPU regions for kernel protections and leave the remaining for the application writer. This ensures that the application writer cannot override kernel protections. We thank the SecLab team at Northeastern University for reporting this issue. Signed-off-by: Gaurav Aggarwal <aggarg@amazon.com> |
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| .. | ||
| ARMClang | ||
| ARMv8M | ||
| BCC/16BitDOS | ||
| CCS | ||
| CodeWarrior | ||
| Common | ||
| GCC | ||
| IAR | ||
| Keil | ||
| MemMang | ||
| MikroC/ARM_CM4F | ||
| MPLAB | ||
| MSVC-MingW | ||
| oWatcom/16BitDOS | ||
| Paradigm/Tern_EE | ||
| Renesas | ||
| Rowley | ||
| RVDS | ||
| SDCC/Cygnal | ||
| Softune | ||
| Tasking/ARM_CM4F | ||
| ThirdParty | ||
| WizC/PIC18 | ||
| CMakeLists.txt | ||
| readme.txt | ||
Each real time kernel port consists of three files that contain the core kernel components and are common to every port, and one or more files that are specific to a particular microcontroller and/or compiler. + The FreeRTOS/Source/Portable/MemMang directory contains the five sample memory allocators as described on the https://www.FreeRTOS.org WEB site. + The other directories each contain files specific to a particular microcontroller or compiler, where the directory name denotes the compiler specific files the directory contains. For example, if you are interested in the [compiler] port for the [architecture] microcontroller, then the port specific files are contained in FreeRTOS/Source/Portable/[compiler]/[architecture] directory. If this is the only port you are interested in then all the other directories can be ignored.