Fix StatInterop to include new signature

[eerhardt]

The LStat native method was updated to include a new field, but the SDK copy wasn't updated. Adding the new field to fix interop issues and crashes.

Fix dotnet/runtime#72308

I verified this fixes the issue manually. I'm not sure how to test this in CI. @dsplaisted - any thoughts?

[dsplaisted]

I think this is a great reason why we don't recommend people to p/invoke into our System.*.Native shims. They are not stable ABI.

Is there a better way to do this (call lstat, it looks like) that is less likely to break?

[eerhardt]

Is there a better way to do this (call lstat, it looks like) that is less likely to break?

Unfortunately the best way I know of currently is to use https://github.com/mono/mono.posix, but that doesn't work on alpine according to mono/mono.posix#18.

The issue with p/invoking directly into libc's lstat is that it moves around based on which unix you are on.

In .NET 7, we added support for getting Unix File Modes with dotnet/runtime#69980. Using that would eliminate all but one usage: getting the owner of a file. We don't currently have that API in .NET. We have a few issues that touch on it like dotnet/runtime#928 and dotnet/runtime#17540. If dotnet/sdk really needs to get the owner of the file/folder, we should consider adding these APIs to .NET.

[eerhardt]

I think this is a great reason why we don't recommend people to p/invoke into our System.*.Native shims. They are not stable ABI.

I've opened #26919 to track the underlying issue here.

[eerhardt]

@dsplaisted - any more thoughts here? Should we merge this to unblock the arm64 scenarios?

[ivdiazsa]

@eerhardt This looks great! I was wondering though, should we open another tracking issue for the missing directory creation like pointed here dotnet/runtime#72308 (comment) ?

[eerhardt]

I was wondering though, should we open another tracking issue for the missing directory creation like pointed here dotnet/runtime#72308 (comment) ?

Feel free to open it if it is causing problems. Just remember to include repro steps.

[mangod9]

@dsplaisted is this good to merge? Would the incorrect layout explain possible memory corruption we were observing?

[dsplaisted]

@dsplaisted is this good to merge? Would the incorrect layout explain possible memory corruption we were observing?

I'm not an expert on native interop, but I was expecting that yes, this would explain the native crashes from dotnet/runtime#72308