[mono] TestUserCredentialsPropertiesOnWindows and other tests fail with "Token cannot be zero."

[akoeplinger]

This outerloop test fails on Windows on Mono:

    System.Diagnostics.Tests.ProcessStartInfoTests.TestUserCredentialsPropertiesOnWindows [FAIL]
      System.ArgumentException : Token cannot be zero.
      Stack Trace:
        /_/src/libraries/System.Security.Principal.Windows/src/System/Security/Principal/WindowsIdentity.cs(293,0): at System.Security.Principal.WindowsIdentity.DuplicateAccessToken(IntPtr accessToken)
        /_/src/libraries/System.Security.Principal.Windows/src/System/Security/Principal/WindowsIdentity.cs(320,0): at System.Security.Principal.WindowsIdentity.CreateFromToken(IntPtr userToken)
        /_/src/libraries/System.Security.Principal.Windows/src/System/Security/Principal/WindowsIdentity.cs(107,0): at System.Security.Principal.WindowsIdentity..ctor(IntPtr userToken, String authType, Int32 isAuthenticated)
        /_/src/libraries/System.Security.Principal.Windows/src/System/Security/Principal/WindowsIdentity.cs(63,0): at System.Security.Principal.WindowsIdentity..ctor(IntPtr userToken)
        /_/src/libraries/Common/tests/TestUtilities/System/WindowsIdentityFixture.cs(108,0): at System.WindowsTestAccount.CreateUser()
        /_/src/libraries/Common/tests/TestUtilities/System/WindowsIdentityFixture.cs(47,0): at System.WindowsTestAccount..ctor(String userName)
        /_/src/libraries/System.Diagnostics.Process/tests/ProcessStartInfoTests.cs(472,0): at System.Diagnostics.Tests.ProcessStartInfoTests.TestUserCredentialsPropertiesOnWindows()
        /_/src/mono/System.Private.CoreLib/src/System/Reflection/MethodInvoker.Mono.cs(30,0): at System.Reflection.MethodInvoker.InterpretedInvoke(Object obj, IntPtr* args)
        /_/src/libraries/System.Private.CoreLib/src/System/Reflection/MethodInvoker.cs(59,0): at System.Reflection.MethodInvoker.Invoke(Object obj, IntPtr* args, BindingFlags invokeAttr)

Filing this issue to track disabling the test (sometimes with a bit different stacktrace).

The same applies to these tests:

• TestUserNetworkCredentialsPropertiesOnWindows
• RunImpersonated_NameResolution
• RunImpersonatedAsync_TaskAndTaskOfT
• RunImpersonatedAsync_NameResolution

[danmoseley]

Any idea how this could be Mono only? Some interop bug?

[akoeplinger]

No idea, I haven't looked at it. It's possible that this boils down to some interop thing that Mono doesn't support, if it's by design we can disable the tests completely on Mono. /cc @lateralusX

[lateralusX]

@akoeplinger, was this on test runs using debug runtime S.P.C builds? Looks like this change:

#71991

added an new field to the SafeHandle class on debug builds:

runtime/src/libraries/System.Private.CoreLib/src/System/Runtime/InteropServices/SafeHandle.cs

Line 32 in dcda1e0

private readonly string? _ctorStackTrace;

that is not accounted for in Mono's SafeHandle native representation:

runtime/src/mono/mono/metadata/class-internals.h

Line 677 in dcda1e0

void *handle;

so Mono still assumes first field is the handle, Mono uses sequential layout for SafeHandle:

runtime/src/mono/System.Private.CoreLib/src/System/Runtime/InteropServices/SafeHandle.Mono.cs

Line 7 in dcda1e0

[StructLayout(LayoutKind.Sequential)]

while on debug build, its now a string to a callstack as the first field, so either we would need to do similar change in Mono like done on CoreCLR, add a MonoString * to the struct for debug builds of runtime and S.P.C, eliminate the field on Mono runtime or don't make it the first field in the class layout.

[akoeplinger]

@lateralusX I don't remember whether it was only on debug but your explanation makes sense, do you have time to make a PR? I don't have a working Windows environment at the moment.

[lateralusX]

@akoeplinger, I can look at it, do you have the PR that disabled the failing tests?

@stephentoub, any reason why m_ctorStackTrace added in #71991 was added as first field in SafeHandle class? Could it be moved to the be the last field making sure Mono's native representation of SafeHandle:

runtime/src/mono/mono/metadata/class-internals.h

Line 677 in dcda1e0

void *handle;

can stay the same on both debug/release builds since we only care about the offset to handle field in the allocated object when marshalling.

[akoeplinger]

@lateralusX I'm working on disabling tests in #79885 so it's still enabled in main (didn't have time to finish the PR before the holiday break)