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Fix a null reference exception when 'Runspace.DefaultRunspace' is null #21344

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merged 1 commit into from Mar 14, 2024

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@daxian-dbw daxian-dbw commented Mar 14, 2024

PR Summary

Fix #21253

Fix a null reference exception when Runspace.DefaultRunspace == null.
This issue happens when the WDAC Audit feature is enabled on the client machine.

Enter-PSSession will push a RemoteRunspace to the RunspaceRef in ConsoleHost, then the next input loop will use the RemoteRunspace to create a pipeline. The call to LogWDACAuditMessage happens when creating that pipeline, and at that point, we are still in the starting thread of pwsh, not a Pipeline Execution Thread, so the local-thread-storage property Runspace.DefaultRunspace is null.

The fix is to check on Runspace.DefaultRunspace?.Id == 1. This PR also does some cleanup of the code.

PR Checklist

@daxian-dbw daxian-dbw added CL-General Indicates that a PR should be marked as a general cmdlet change in the Change Log BackPort-7.4.x-Consider labels Mar 14, 2024
@daxian-dbw daxian-dbw self-assigned this Mar 14, 2024

This PR has 9 quantified lines of changes. In general, a change size of upto 200 lines is ideal for the best PR experience!


Quantification details

Label      : Extra Small
Size       : +4 -5
Percentile : 3.6%

Total files changed: 1

Change summary by file extension:
.cs : +4 -5

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Wow great catch, LGTM!

@daxian-dbw daxian-dbw merged commit d67a82d into PowerShell:master Mar 14, 2024
36 of 38 checks passed
@daxian-dbw daxian-dbw deleted the nullref branch March 14, 2024 18:39
@daxian-dbw
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The test Test-Connection.MTUSizeDetect.MTUSizeDetect keeps failing in macOS CIs, but it's not related to the changes in this PR.

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I am receiving this error with 7..4.2 version, are there any relevance here.

There is no Runspace available to run scripts in this thread. You can provide one in the DefaultRunspace property of the System.Management.Automation.Runspaces.Runspace type. The script block you attempted to invoke was:

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@msekkappan Nah no relevance, the exception you're getting is normal and expected. For more info I'd recommend sharing your code and the exception in the PowerShell community discord.

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Enter-PsSession: NullReferenceException crash in 7.4.1
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