| Bug #88172 | AbandonedConnectionCleanupThread does not handle SecurityException | ||
|---|---|---|---|
| Submitted: | 21 Oct 2017 8:17 | Modified: | 9 Sep 19:17 |
| Reporter: | Stephen Booth | Email Updates: | |
| Status: | Won't fix | Impact on me: | |
| Category: | Connector / J | Severity: | S3 (Non-critical) |
| Version: | 5.1.42 | OS: | Any |
| Assigned to: | CPU Architecture: | Any | |
| Tags: | SecurityException, securityManager | ||
[23 Oct 2017 13:32]
Chiranjeevi Battula
Hello Stephen, Thank you for the bug report. Verified based on internal discussion with dev's. Thanks, Chiranjeevi.
[9 Sep 19:15]
Filipe Silva
Posted by developer: Thread.setContextClassLoader isn't the only operation that can trigger an AccessControlException; even reading system properties can. Avoiding the exception in AbandonedConnectionCleanupThread alone isn’t sufficient for the driver to work. A better option would be to include the necessary grants in the conf/catalina.policy file. As of Connector/J 9.4.0, the following permissions allow minimal usage of the driver, but others may be needed depending on the features in use: - permission java.util.PropertyPermission "com.mysql.cj.disableAbandonedConnectionCleanup", "read"; - permission java.util.PropertyPermission "javax.net.*", "read"; - permission java.lang.RuntimePermission "setContextClassLoader"; - permission java.net.SocketPermission "*:*", "connect,resolve"; Permissions can also be granted on a per-jar basis, so I recommend defining a dedicated section for the Connector/J JAR file. That said, keep in mind that SecurityManager has been deprecated in Java 17 and is expected to be removed in a future Java release. Because of this, it’s possible that this issue may never be addressed.
Description: The AbandonedConnectionCleanupThread calls Thread.setContextClassLoader in a static block which may throw a SecurityException if a SecurityManager is in place. This can prevent the driver class from instantiating in tomcat with the -security flag enabled. Caused by: java.security.AccessControlException: access denied ("java.lang.RuntimePermission" "setContextClassLoader") at java.security.AccessControlContext.checkPermission(AccessControlContext.java:472) at java.security.AccessController.checkPermission(AccessController.java:884) at java.lang.SecurityManager.checkPermission(SecurityManager.java:549) at java.lang.Thread.setContextClassLoader(Thread.java:1474) at com.mysql.jdbc.AbandonedConnectionCleanupThread$1.newThread(AbandonedConnectionCleanupThread.java:50) at java.util.concurrent.ThreadPoolExecutor$Worker.<init>(ThreadPoolExecutor.java:619) at java.util.concurrent.ThreadPoolExecutor.addWorker(ThreadPoolExecutor.java:932) at java.util.concurrent.ThreadPoolExecutor.execute(ThreadPoolExecutor.java:1367) How to repeat: Run Class.forName("com.mysql.jdbc.Driver") from a tomcat application when tomcat is run with the -security flag. Same in test class with a security.policy file that dis-allows setContextClassLoader Suggested fix: Trap the exception Running with the thread classloader is better than not loading at all.