[I] LoggerNameLevelRewritePolicy matches sibling packages that share a logger-name prefix [logging-log4j2]

["sharanggupta (via GitHub)" <gi...@apache.org>]

sharanggupta opened a new issue, #4412:
URL: https://github.com/apache/logging-log4j2/issues/4412

   **Describe the bug**
   `LoggerNameLevelRewritePolicy.rewrite()` matches the configured logger name with `String.startsWith`, with no check for a following `.` or exact-match boundary. A policy configured for `logger="com.foo"` therefore also matches an unrelated sibling package such as `com.foobar.Baz`, which merely happens to share the same character prefix without being a sub-logger of `com.foo` at all.
   
   This is inconsistent with how every other logger-name-hierarchy feature in Log4j works (e.g. `<Logger name="com.foo">` resolves by progressively truncating at the last dot, never by substring prefix matching), and it's a silent effect: a `WARN` (or any configured level) from the unrelated package gets rewritten/demoted with no error, warning, or indication anything unexpected happened.
   
   **Environment**
   - Log4j version: 2.26.1 (latest stable; also reproduces on `2.x`/3.0.0-beta3 source)
   - OS: macOS (environment-independent; pure string logic)
   - JDK: 17
   
   **To Reproduce**
   ```java
   KeyValuePair[] rewrite = { new KeyValuePair("WARN", "DEBUG") };
   LoggerNameLevelRewritePolicy policy = LoggerNameLevelRewritePolicy.createPolicy("com.foo", rewrite);
   
   LogEvent event = Log4jLogEvent.newBuilder()
           .setLoggerName("com.foobar.PaymentProcessor")
           .setLevel(Level.WARN)
           .setMessage(new SimpleMessage("payment declined"))
           .build();
   
   LogEvent rewritten = policy.rewrite(event);
   // rewritten.getLevel() is DEBUG, even though "com.foobar.PaymentProcessor" is not
   // a descendant of "com.foo" — it's an unrelated sibling package.
   ```
   
   **Expected behavior**
   A rule configured for `"com.foo"` should only affect `"com.foo"` itself and its true descendants (`"com.foo.Bar"`, etc.), not an unrelated package that happens to share the same character prefix.
   
   **Additional context**
   I have a fix + regression test ready and will open a PR referencing this issue.


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Re: [I] LoggerNameLevelRewritePolicy matches sibling packages that share a logger-name prefix [logging-log4j2]

["ramanathan1504 (via GitHub)" <gi...@apache.org>]

ramanathan1504 closed issue #4412: LoggerNameLevelRewritePolicy matches sibling packages that share a logger-name prefix
URL: https://github.com/apache/logging-log4j2/issues/4412


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