Implement uaccess validation with objtool
Nobody has claimed this yet.
- Dominant language
- No language data
- Stars
- 14
- Forks
- 0
- PR merge metrics
- No merged PRs in 30d
Description
On x86 objtool can perform uaccess validation, that is check that no function is called with user access is enabled after user_access_begin() and before user_access_end()
First tentative at https://patchwork.ozlabs.org/project/linuxppc-dev/list/?state=*&series=363369
The challenge is to implement switch/case code walk, the way it is implemented for x86 is too weak and doesn't fit the code GCC generates for powerpc because powerpc RISC assembly provides much more flexibility to GCC than on x86.
objtool switch/case analysis needs to be re-written in a more reliable way.
Contributor guide
No contributing guide indexed for this repository
First steps
- Read the whole issue, then the project's contributing guide.
- Comment on the issue to say you are picking it up — it saves two people doing the same work.
- Fork the repository and make your change on a branch.
- Open a pull request that references the issue number.
Research direction
Start with the tentative patch linked in the issue and the existing x86 objtool switch/case analysis. Compare that approach with the code GCC generates for powerpc and define a more reliable analysis; done means objtool can validate uaccess regions correctly on powerpc without relying on the weak x86 approach.
Written by the indexing model from the issue text.
Assessment
- Domain
- operating-systems, tooling
- Issue type
- Feature
- Difficulty
- 5/5
- Estimated time
- Over a week
- Activity status
- Stale
- Clarity
- Needs clarification
- Newbie friendliness
- 25/100