Upgrading to Netty 4.2

[tishun]

Closes #3294

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[tishun]

@a-TODO-rov , @ggivo before merging we need to test carefully the native transports integration

[tishun]

Good to also check the following, according to the migration guide::

• Ensure endpoint validation is explicitly configured for client TLS connections.
• Explicitly configure your system to use the pooled allocator.

[rhanton]

Upvoting this issue 👍 . This is transitively causing me grief over CVE-2025-58057 in netty < 4.1.125 via lettuce via spring-data-redis. Thanks for the work @tishun !

[ggivo]

@a-TODO-rov , @ggivo before merging we need to test carefully the native transports integration

@tishun
By testing, do you have something specific in mind?
What comes to my mind is to run existing integration test using lettuce configured with (netty-transport-classes-epoll & netty-transport-classes-io_uring ) on Linux & netty-transport-classes-kqueue on ОСѝ?

[tishun]

By testing I meant that for all three native transports - io_uring, kqueue and epoll - we need to start some test load and verify the driver loads and works as expected. No need to run the entire suite of E2E tests, but if it is easy we can also do that.

[tishun]

Good to also check the following, according to the migration guide::

• Ensure endpoint validation is explicitly configured for client TLS connections.
• Explicitly configure your system to use the pooled allocator.

I think we are good on the sslContextBuilder.endpointIdentificationAlgorithm(String) part too.

[tishun]

Good to also check the following, according to the migration guide::

• Ensure endpoint validation is explicitly configured for client TLS connections.
• Explicitly configure your system to use the pooled allocator.

For the pooled allocator I think we can go ahead and use the adaptive one. This is a breaking change, but we are making a major release, so we should be fine. Users can easily override that if they want to use the pooled allocator.