Rust: Avoid location-based variable analysis#18462
Merged
hvitved merged 3 commits intogithub:mainfrom Jan 15, 2025
Merged
Conversation
9da26a8 to
6c0cfb0
Compare
6c0cfb0 to
4c83022
Compare
4c83022 to
33e6d63
Compare
Contributor
There was a problem hiding this comment.
Copilot reviewed 6 out of 10 changed files in this pull request and generated 1 comment.
Files not reviewed (4)
- rust/ql/lib/codeql/rust/elements/internal/VariableImpl.qll: Language not supported
- rust/ql/test/library-tests/dataflow/strings/inline-taint-flow.expected: Language not supported
- rust/ql/test/library-tests/variables/variables.ql: Language not supported
- rust/ql/test/query-tests/unusedentities/UnusedValue.expected: Language not supported
Tip: If you use Visual Studio Code, you can request a review from Copilot before you push from the "Source Control" tab. Learn more
paldepind
approved these changes
Jan 15, 2025
| sink(format!("{}", s1)); // $ MISSING: hasTaintFlow=34 | ||
| sink(format!("{s1} and {s3}")); // $ MISSING: hasTaintFlow=34 | ||
| sink(format!("{}", s1)); // $ hasTaintFlow=34 | ||
| sink(format!("{s1} and {s3}")); // $ hasTaintFlow=34 |
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
Sign up for free
to join this conversation on GitHub.
Already have an account?
Sign in to comment
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Outdated suggestions cannot be applied.This suggestion has been applied or marked resolved.Suggestions cannot be applied from pending reviews.Suggestions cannot be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.
Before this PR, we were relying on the source location of variable declarations and accesses for name-binding. However, this does not work for variables declared/accessed inside macros, where the original source locations are not available.
This PR consequently rewrites the logic to be purely AST based, by computing pre-order tree-traversal numbers for (relevant) AST nodes, and then using those numbers instead of source location start-line/columns.
This approach mostly works, except we are not able to respect the macro hygiene rules of Rust, since the extractor does not supply us with a syntax context. I originally noticed this in an earlier DCA run, where a new
rust/unused-variablefalse-positive result was added, and I have consequently added this FP to our test suite.Commit-by-commit review is suggested.