Dilithium 5 issue in 32-bit

[Crawl12321]

Hello,

During our integration of libOQS, we’ve stumbled on an issue with DILITHIUM5 (DILITHIUM 2 and 3 are working just fine).
The situation is the following:

• We are using several CoreI3/5/7 64-bit processors of different generations, some old and some new
• On these processors, we put a 32-bit Linux OS (kernel 5.15) built with buildroot
• We’ve successfully integrated libOQS in our Linux (at first on a 3rd-generation CoreI7)
• We can call DILITHIUM2 and 3 related cryptographic functions (key-pair generation, signature, verification) without any issue
• We can call DILITHIUM5 key-pair generation, without any issue
• When we can call DILITHIUM5 signature, there is a segmentation fault in libOQS
  Would you, by any chance, see a reason for this issue? Is libOQS fully 32-bit compatible? Could there be a correlation with the processors hardware features?

[baentsch]

Is libOQS fully 32-bit compatible? Could there be a correlation with the processors hardware features?

Most definitely you could have hit on a hardware support "snag": The hardware/platform support status of liboqs is under discussion, so I personally would not vouch for all 32bitters right now. What you should do, though, is build/use liboqs without any hardware optimization thus activating reference code that should work everywhere. If it does not, please open a complete bug report.

[Crawl12321]

Thank you for your answer @baentsch :)

We stumbled on the root of our issue while trying to make an exemple, the dilithium5 signature process was exceeding the thread stack size. Problem solved.