Quality RTOS & Embedded Software

 Real time embedded FreeRTOS RSS feed 
Real time embedded FreeRTOS mailing list 
Quick Start Supported MCUs PDF Books Trace Tools Ecosystem TCP & FAT Training


FreeRTOS-MPU security (privileges)

Posted by Stefano Cristalli on August 16, 2013
Hello, I am currently testing FreeRTOS-MPU on STM32F4, and it has occured to me that a restricted task could call library functions xTaskCreate or xTaskCreateRestricted in order to spawn other tasks, perhaps with malicious code inside them.
Is that a behavior that should be blocked? How would someone prevent such tasks from calling xTaskCreate?

Thanks in advance.

RE: FreeRTOS-MPU security (privileges)

Posted by Richard on August 16, 2013
Currently there is no way of preventing a non-privileged task from creating a privileged task, but it could conceivable done relatively simply by updating the implementation of MPU_xTaskGenericCreate() in the MPU port layer's port.c file. The update would check to see if the scheduler was running, and if so, only allow a privileged task to be created if the MCU was already running in the privileged mode when MPU_xTaskGenericCreate() was called (that information is already known because it is stored in the xRunningPrivileged variable within the function).

However...in statically linked small systems there is an assumption that the system architecture is familiar with all the code s/he is building into the project. It is therefore unlikely to include malicious code, so any additional safe guards would primarily safe guard against simple design mistakes.


[ Back to the top ]    [ About FreeRTOS ]    [ Sitemap ]    [ ]

Copyright (C) 2004-2010 Richard Barry. Copyright (C) 2010-2016 Real Time Engineers Ltd.
Any and all data, files, source code, html content and documentation included in the FreeRTOSTM distribution or available on this site are the exclusive property of Real Time Engineers Ltd.. See the files license.txt (included in the distribution) and this copyright notice for more information. FreeRTOSTM and FreeRTOS.orgTM are trade marks of Real Time Engineers Ltd.

Latest News:

FreeRTOS V9.0.0 is now available for download.

Free TCP/IP and file system demos for the RTOS

Sponsored Links

⇓ Now With No Code Size Limit! ⇓
⇑ Free Download Without Registering ⇑

FreeRTOS Partners

ARM Connected RTOS partner for all ARM microcontroller cores

Renesas Electronics Gold Alliance RTOS Partner.jpg

Microchip Premier RTOS Partner

RTOS partner of NXP for all NXP ARM microcontrollers

Atmel RTOS partner supporting ARM Cortex-M3 and AVR32 microcontrollers

STMicro RTOS partner supporting ARM7, ARM Cortex-M3, ARM Cortex-M4 and ARM Cortex-M0

Xilinx Microblaze and Zynq partner

Silicon Labs low power RTOS partner

Altera RTOS partner for Nios II and Cortex-A9 SoC

Freescale Alliance RTOS Member supporting ARM and ColdFire microcontrollers

Infineon ARM Cortex-M microcontrollers

Texas Instruments MCU Developer Network RTOS partner for ARM and MSP430 microcontrollers

Cypress RTOS partner supporting ARM Cortex-M3

Fujitsu RTOS partner supporting ARM Cortex-M3 and FM3

Microsemi (previously Actel) RTOS partner supporting ARM Cortex-M3

Atollic Partner

IAR Partner

Keil ARM Partner

Embedded Artists