fix(memory): ensure we are not mmapping beyond EOF on restore from file #5480
Conversation
This file contains hidden or bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
Codecov Report✅ All modified and coverable lines are covered by tests. Additional details and impacted files@@ Coverage Diff @@
## main #5480 +/- ##
=======================================
Coverage 82.64% 82.64%
=======================================
Files 269 269
Lines 27731 27740 +9
=======================================
+ Hits 22917 22926 +9
Misses 4814 4814
Flags with carried forward coverage won't be shown. Click here to find out more. ☔ View full report in Codecov by Sentry. 🚀 New features to boost your workflow:
|
Manciukic
added
the
Status: Awaiting review
JackThomson2
previously approved these changes
Oct 15, 2025
ShadowCurse
reviewed
Oct 15, 2025
[email protected] removed the bounds check in the memory region creation as not every fd is seekable. This causes a SIGBUS if for some reason the snapshot file is smaller than the sum of the regions and the guest tries to access a page beyond EOF. This issue was caught by the fuzzer. This change adds the bounds check in the snapshot_file function and unit tests to ensure this behaviour is maintained. Signed-off-by: Riccardo Mancini <[email protected]>
Manciukic
force-pushed
the
check-snapshot-file-len
branch
from
1ac2a71 to
b255d12
Compare
JackThomson2
approved these changes
Oct 15, 2025
ShadowCurse
approved these changes
Oct 15, 2025
Sign up for free
to join this conversation on GitHub.
Already have an account?
Sign in to comment
3 participants
Add this suggestion to a batch that can be applied as a single commit.
This suggestion is invalid because no changes were made to the code.
Suggestions cannot be applied while the pull request is closed.
Suggestions cannot be applied while viewing a subset of changes.
Only one suggestion per line can be applied in a batch.
Add this suggestion to a batch that can be applied as a single commit.
Applying suggestions on deleted lines is not supported.
You must change the existing code in this line in order to create a valid suggestion.
Outdated suggestions cannot be applied.
This suggestion has been applied or marked resolved.
Suggestions cannot be applied from pending reviews.
Suggestions cannot be applied on multi-line comments.
Suggestions cannot be applied while the pull request is queued to merge.
Suggestion cannot be applied right now. Please check back later.
Changes
This change adds the bounds check in the snapshot_file function and unit tests to ensure this behaviour is maintained.
Reason
[email protected] removed the bounds check in the memory region creation as not every fd is seekable. This causes a SIGBUS if for some reason the snapshot file is smaller than the sum of the regions and the guest tries to access a page beyond EOF. This issue was caught by the fuzzer.
License Acceptance
By submitting this pull request, I confirm that my contribution is made under
the terms of the Apache 2.0 license. For more information on following Developer
Certificate of Origin and signing off your commits, please check
CONTRIBUTING.md.PR Checklist
tools/devtool checkbuild --allto verify that the PR passesbuild checks on all supported architectures.
tools/devtool checkstyleto verify that the PR passes theautomated style checks.
how they are solving the problem in a clear and encompassing way.
in the PR.
CHANGELOG.md.Runbook for Firecracker API changes.
integration tests.
TODO.rust-vmm.