Using stack-protector with CubeIDE

[Konami]

I'm looking for some info about and help with using -fstack-protector and similar compiler options with STM32CubeIde. I've never used these flags before, but enabling them does seem to compile fine. Am I correct in assuming that the GCC supplied with Cube supports this? Where is the implementation of required functions (ie. __stack_chk_guard)? Can I just override these?

Any guidance on how to use these options for STM32?

[FBL · Accepted solution]

Hello @DB.7ujak​ 

Indeed, it is supported.

In order to use -fstack-protector in STM32CubeIDE, you can follow these steps:

1. Open your project in CubeIDE, and go to Project > Properties.
2. In the Properties dialog box, navigate to C/C++ Build > Settings.
3. In the Settings page, navigate to Tool Settings > MCU C Compiler > Miscellaneous.
4. In the Miscellaneous page, check the box next to "-fstack-protector" to enable the flag.

Once you have enabled -fstack-protector, the required functions, including __stack_chk_guard, will be automatically generated by the compiler. You do not need to override these functions, as they are part of the compiler's implementation. It is a security feature that can prevent buffer overflow.

Hope this helps!

[DreamOnDirac]

Hi

According to the GCC documentation, stack-usage and stack-protection is not the same thing.

https://gcc.gnu.org/onlinedocs/gcc/Instrumentation-Options.html

stack-usage is indeed useful, but it is not the feature that is requested by the OP.

Eric Stryger has made an excellent post about stack-protection here:

https://mcuoneclipse.com/2019/09/28/stack-canaries-with-gcc-checking-for-stack-overflow-at-runtime/ 

I have also made requests on the subject here on this forum

https://community.st.com/t5/stm32cubeide-mcus/please-change-gcc-stack-canary-to-be-weak/td-p/630140 

Best regards

Martin