Fix Export-PSSession to not throw error when a rooted path is specified for -OutputModule

[daxian-dbw]

PR Summary

The 7.0.10 release contains a commit for a potential security issue: 38e55e1. Here is the announcement about it: PowerShell/Announcements#31.

This particular change from that commit caused a regression in Azure Function when running Import-Module <module-name> -UseWindowsPowerShell, where the user's module path doesn't exist. That command worked fine with the PowerShell 7.0.9 SDK but started to fail with the PowerShell 7.0.11 SDK.

The root cause is that when Export-PSSession is used by Import-Module -UseWindowsPowerShell, a rooted path is always specified to the -OutputModule parameter, so it doesn't matter whether the user's module path exists or not because it doesn't need it to identify the directory to use.

The fix is to use the specified rooted path directly. Actually, Path.Combine(path1, path2) will return path2 if it's rooted.
The error message is also updated:

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[iSazonov]

It makes sense for PowerShell Committee to review OutModule parameter. I think the case is the same as #3174 (#11701) - OutModule parameter should be LiteralPath. If so we could simplify CreateModuleDirectory() method.

[ghost]

🎉v7.3.0-preview.6 has been released which incorporates this pull request.:tada:

Handy links:

• Release Notes

[adityapatwardhan]

/backport release/v7.2.6

[adityapatwardhan]

/backport to release/v7.0.12

[github-actions]

Started backporting to release/v7.0.12: https://github.com/PowerShell/PowerShell/actions/runs/2784794011

GitHub

Fix `Export-PSSession` to not throw error when a rooted path is specified for `-OutputModule` · PowerShell/PowerShell@0e4d2e4

PowerShell for every system! Contribute to PowerShell/PowerShell development by creating an account on GitHub.

[adityapatwardhan]

/backport to release/v7.2.6

[github-actions]

@adityapatwardhan backporting to release/v7.0.12 failed, the patch most likely resulted in conflicts:

$ git am --3way --ignore-whitespace --keep-non-patch changes.patch

Applying: Fix Export-PSSession to not throw error when a rooted path is specified for -OutputModule
Applying: Update comment
error: sha1 information is lacking or useless (src/System.Management.Automation/utils/PathUtils.cs).
error: could not build fake ancestor
hint: Use 'git am --show-current-patch=diff' to see the failed patch
Patch failed at 0002 Update comment
When you have resolved this problem, run "git am --continue".
If you prefer to skip this patch, run "git am --skip" instead.
To restore the original branch and stop patching, run "git am --abort".
Error: The process '/usr/bin/git' failed with exit code 128

Please backport manually!

[github-actions]

Started backporting to release/v7.2.6: https://github.com/PowerShell/PowerShell/actions/runs/2784796745

GitHub

Fix `Export-PSSession` to not throw error when a rooted path is specified for `-OutputModule` · PowerShell/PowerShell@0e4d2e4

PowerShell for every system! Contribute to PowerShell/PowerShell development by creating an account on GitHub.

[ghost]

🎉v7.0.12 has been released which incorporates this pull request.:tada:

Handy links:

• Release Notes

[ghost]

🎉v7.2.6 has been released which incorporates this pull request.:tada:

Handy links:

• Release Notes