feat(v2): improve aslr, adjust max memory size#1263

Merged

jounathaen merged 2 commits intohermit-os:mainfrom

n0toose:v2-aslr-memory-improvements

Mar 9, 2026

Member

n0toose commented Feb 17, 2026 •

edited

Loading

Refactor of ASLR to support v2 and v1 images, which achieves the following:

It reduces code duplication for generate_address
Removes a useless parameter
Demonstrates different handling between v1 and v2 images that correspondingly allows users to use v2 with higher memory amounts

Fixes #1257

n0toose marked this pull request as draft

February 17, 2026 14:48

n0toose added the feature/security label

n0toose force-pushed the v2-aslr-memory-improvements branch from 626b749 to d2830e8 Compare

February 17, 2026 14:49

github-actions bot removed the feature/security label

codecov bot commented Feb 17, 2026 •

edited

Loading

Codecov Report

❌ Patch coverage is 95.34884% with 6 lines in your changes missing coverage. Please review.
✅ Project coverage is 75.91%. Comparing base (beb184c) to head (45e752a).
⚠️ Report is 2 commits behind head on main.

Files with missing lines	Patch %	Lines
src/vm.rs	96.55%	4 Missing ⚠️
src/linux/x86_64/kvm_cpu.rs	84.61%	2 Missing ⚠️

Additional details and impacted files

@@            Coverage Diff             @@
##             main    #1263      +/-   ##
==========================================
+ Coverage   75.29%   75.91%   +0.61%     
==========================================
  Files          27       27              
  Lines        3955     4040      +85     
==========================================
+ Hits         2978     3067      +89     
+ Misses        977      973       -4

☔ View full report in Codecov by Sentry.
📢 Have feedback on the report? Share it here.

🚀 New features to boost your workflow:

❄️ Test Analytics: Detect flaky tests, report on failures, and find test suite problems.

n0toose force-pushed the v2-aslr-memory-improvements branch 2 times, most recently from 0c9ffcc to 7e42d07 Compare

February 17, 2026 15:17

fogti reviewed

View reviewed changes

src/arch/mod.rs Outdated Show resolved Hide resolved

fogti reviewed

View reviewed changes

src/arch/mod.rs Outdated Show resolved Hide resolved

Member Author

n0toose commented Feb 17, 2026

wait, this is still in development and there's a few nasty bugs i just caught

Contributor

fogti commented Feb 17, 2026

ik.

n0toose force-pushed the v2-aslr-memory-improvements branch 2 times, most recently from beb89e2 to a67f146 Compare

February 17, 2026 15:42

n0toose commented

View reviewed changes

src/linux/x86_64/kvm_cpu.rs Outdated Show resolved Hide resolved

n0toose marked this pull request as ready for review

February 17, 2026 15:44

n0toose commented

View reviewed changes

src/arch/mod.rs Outdated Show resolved Hide resolved

n0toose requested review from fogti and jounathaen

February 17, 2026 15:45

n0toose force-pushed the v2-aslr-memory-improvements branch from a67f146 to 43428ce Compare

February 17, 2026 15:48

fogti reviewed

View reviewed changes

src/arch/mod.rs Outdated Show resolved Hide resolved

n0toose mentioned this pull request

ci(labeler): remove label sync #1264

Merged

jounathaen reviewed

View reviewed changes

src/arch/mod.rs Outdated Show resolved Hide resolved

n0toose force-pushed the v2-aslr-memory-improvements branch from 43428ce to 53a2d3b Compare

February 17, 2026 16:57

n0toose requested a review from jounathaen

February 17, 2026 18:53

jounathaen reviewed

View reviewed changes

src/arch/mod.rs Outdated Show resolved Hide resolved

jounathaen reviewed

View reviewed changes

src/arch/mod.rs Outdated Show resolved Hide resolved

jounathaen reviewed

View reviewed changes

src/linux/x86_64/kvm_cpu.rs Show resolved Hide resolved

n0toose force-pushed the v2-aslr-memory-improvements branch from 7f36afb to d25cd6c Compare

February 18, 2026 14:43

fogti reviewed

View reviewed changes

src/arch/mod.rs Outdated Show resolved Hide resolved

Contributor

fogti commented Feb 18, 2026

btw. please rebase on main to get rid of the Cargo.toml divergence.

n0toose force-pushed the v2-aslr-memory-improvements branch 7 times, most recently from fee3965 to fd102da Compare

February 18, 2026 22:08

n0toose mentioned this pull request

Investigate fuzzing introduction #1274

Open

n0toose force-pushed the v2-aslr-memory-improvements branch from fd102da to 7e168b2 Compare

February 19, 2026 15:04

jounathaen reviewed

View reviewed changes

src/vm.rs Show resolved Hide resolved

n0toose force-pushed the v2-aslr-memory-improvements branch 2 times, most recently from 4e8b27d to 876b2f7 Compare

March 6, 2026 01:10

fogti reviewed

View reviewed changes

src/vm.rs Show resolved Hide resolved


          feat(v2): refactor aslr, increase v2 max memory

8ea7742

Refactor of ASLR to support `v2` and `v1` images, which achieves the
following:
- Move start address derivation into `generate_guest_start_address`
  (f.k.a. `generate_address`)
- Reduce code duplication
- Remove a useless parameter
- Introduce different handling between v1 and v2 images that
  correspondingly allows users to use v2 with higher memory amounts
- Introduce relevant warnings/errors if user-provided parameters
  can cause Uhyve to error
- Add assertions that prevent memory allocations within x86_64 gap

Fixes hermit-os#1257

n0toose force-pushed the v2-aslr-memory-improvements branch from 876b2f7 to 8ea7742 Compare

March 6, 2026 14:01

github-actions bot added the tests label

fogti approved these changes

View reviewed changes

Member Author

n0toose commented Mar 6, 2026

@jounathaen ready for review :)

n0toose added feature/optimization feature/security labels


          test(memory): introduce simple memory integration tests

45e752a

Currently written with v1 in mind.

n0toose force-pushed the v2-aslr-memory-improvements branch from 2dfa251 to 45e752a Compare

March 9, 2026 11:38

n0toose requested review from fogti and jounathaen

March 9, 2026 11:49

fogti approved these changes

View reviewed changes

jounathaen added this pull request to the merge queue

Member

jounathaen commented Mar 9, 2026

Nice! Thank you!

Merged via the queue into hermit-os:main with commit 1ee86ee

11 checks passed

jounathaen deleted the v2-aslr-memory-improvements branch

March 9, 2026 12:52

Sign up for free to join this conversation on GitHub. Already have an account? Sign in to comment

Labels

feature/optimization feature/security tests