PMM-14321: fix pmm-agent crashing when querying system variables #72
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Pull Request Overview
This PR fixes a bounds checking bug in the query fingerprinting logic that could cause an index out of bounds error when processing certain SQL queries. The fix adds a length check before accessing q[qi+1] to prevent potential panics.
- Added bounds checking to prevent index out of range errors
- Added test coverage for system variable queries that trigger the edge case
Reviewed Changes
Copilot reviewed 2 out of 2 changed files in this pull request and generated 1 comment.
| File | Description |
|---|---|
| query/query.go | Added bounds check (qi+1 < len(q)) before accessing q[qi+1] to prevent index out of bounds errors |
| query/query_test.go | Added test case for system variable queries to verify the bug fix works correctly |
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BupycHuk
approved these changes
Oct 30, 2025
This was referenced Oct 31, 2025
JiriCtvrtka
approved these changes
Nov 6, 2025
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PMM-14321