Make netebpfext unit test resilient to fault injection.

[Shankar Seal (shankarseal)]

Co-authored-by: Copilot App 223556219+Copilot@users.noreply.github.com

Description

Fixes #5460 .

Issues

• Fault injection could cause the mock FwpmFilterAdd0() in usersim.dll to fail during the netebpfext test case initialization, prior to NMR hook provider could bind, leaving the corresponding provider unavailable. Subsequent tests assumed initialization had succeeded, accessed the missing provider data, and crashed on a null pointer.
• fault.log file was not getting uploaded
• netebpfext unit test was not built in native flavor.

Changes

The PR includes the following changes.

• Update usersim to support suspend/resume fault injection.
• Suspend usersim fault injection while the netebpfext test helper initializes and tears down.
• Add a unit test that exercises all NMR bindings with fault injection enabled.
• Require all expected NMR bindings for existing tests while excluding helper initialization from fault injection.
• Add a CI step that collects fault-injection logs so they are uploaded with the test results.
• Add NativeOnlyDebug configuration to netebpfext_unit.vcxproj.

Testing

Do any existing tests cover this change? Are new tests needed?

If new tests were added:

• Unit tests are added.
• Driver tests are added.
• Fuzz tests are added.

Documentation

Is there any documentation impact for this change?

Installation

Is there any installer impact for this change?

[Anurag Saxena (saxena-anurag)]

we dont really need nativeonlydebug flavor here. we just need to configure the solution to build "debug" flavor of this project when "nativeonlydebug" is being built (similarly for nativeonlyrelease)

[Anurag Saxena (saxena-anurag)]

nit: since we are already adding this to every test case, we can probably skip suspend / resume entirely and just add a check in require_initialized that either it should be initialized or fault injection should be enabled.

[Copilot]

🟡 Changes recommended

The new nmr_client_handle registration wrapper treats NULL handles as “registered” and may call NmrDeregisterClient(NULL) on registration failure, which can reintroduce crashes under fault injection.

Once you've addressed the issues Copilot identified, you can request another Copilot review.

Pull request overview

This PR hardens the netebpfext unit tests against usersim fault injection during NMR/WFP initialization, preventing null-provider crashes and improving CI diagnostics by ensuring fault-injection logs are collected.

Changes:

• Add a fault-injection policy to the netebpf_ext_helper and introduce require_initialized() so tests fail fast if required NMR providers didn’t bind.
• Add a new unit test that validates all expected NMR bindings while fault injection is enabled.
• Enable building netebpfext_unit under the NativeOnlyDebug configuration and add a CI step to copy fault-injection logs into TestLogs for upload.

File summaries

File	Description
tests/netebpfext_unit/netebpfext_unit.vcxproj	Adds NativeOnlyDebug configuration so the unit test participates in native-only builds.
tests/netebpfext_unit/netebpfext_unit.cpp	Adds an NMR-binding validation test and enforces initialization checks across existing tests.
tests/netebpfext_unit/netebpf_ext_helper.h	Adds fault-injection policy controls and helper state to validate initialization/bindings.
tests/netebpfext_unit/netebpf_ext_helper.cpp	Suspends/resumes fault injection around helper init/teardown and tracks successful hook-provider bindings.
ebpf-for-windows.sln	Wires the netebpfext_unit project into NativeOnlyDebug solution configuration.
.github/workflows/reusable-test.yml	Copies fault-injection logs into TestLogs so they get uploaded with test artifacts.

Review details

• Files reviewed: 7/7 changed files
• Comments generated: 1
• Review effort level: Lite

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