dotnet trace ps running as root fails with System.IO.IOException: No such process : '/proc/2/environ'

[omajid]

Description

I sometimes run dotnet trace as root (uid 0) under Linux. Recent versions of dotnet trace fail to run in this setup. Older versions of dotnet trace work fine.

# dotnet tool install -g dotnet-trace
You can invoke the tool using the following command: dotnet-trace
Tool 'dotnet-trace' (version '10.0.745401') was successfully installed.
# dotnet trace ps
System.IO.IOException: No such process : '/proc/2/environ'
   at Interop.ThrowExceptionForIoErrno(ErrorInfo errorInfo, String path, Boolean isDirError)
   at Microsoft.Win32.SafeHandles.SafeFileHandle.Open(String path, OpenFlags flags, Int32 mode, Boolean failForSymlink, Boolean& wasSymlink, Func`4 createOpenException)
   at Microsoft.Win32.SafeHandles.SafeFileHandle.Open(String fullPath, FileMode mode, FileAccess access, FileShare share, FileOptions options, Int64 preallocationSize, UnixFileMode openPermissions, Int64& fileLength, UnixFileMode& filePermissions, Boolean failForSymlink, Boolean& wasSymlink, Func`4 createOpenException)
   at System.IO.File.OpenHandle(String path, FileMode mode, FileAccess access, FileShare share, FileOptions options, Int64 preallocationSize)
   at System.IO.File.ReadAllBytes(String path)
   at Microsoft.Diagnostics.NETCore.Client.PidIpcEndpoint.GetProcessTmpDir(Int32 hostPid, Boolean& environReadable) in /_/src/Microsoft.Diagnostics.NETCore.Client/DiagnosticsIpc/IpcTransport.cs:line 437
   at Microsoft.Diagnostics.NETCore.Client.DiagnosticsClient.GetProcPublishedProcesses() in /_/src/Microsoft.Diagnostics.NETCore.Client/DiagnosticsClient/DiagnosticsClient.cs:line 512
   at Microsoft.Diagnostics.NETCore.Client.DiagnosticsClient.GetPublishedProcesses() in /_/src/Microsoft.Diagnostics.NETCore.Client/DiagnosticsClient/DiagnosticsClient.cs:line 420
   at Microsoft.Internal.Common.Commands.ProcessStatusCommandHandler.ProcessStatus(TextWriter stdOut, TextWriter stdError) in /_/src/Tools/Common/Commands/ProcessStatus.cs:line 123
# dotnet tool uninstall -g dotnet-trace
Tool 'dotnet-trace' (version '10.0.745401') was successfully uninstalled.
# dotnet tool install --global dotnet-trace --version 9.0.661903
You can invoke the tool using the following command: dotnet-trace
Tool 'dotnet-trace' (version '9.0.661903') was successfully installed.
# dotnet trace ps
 12419  dotnet  /usr/lib64/dotnet/dotnet  dotnet trace ps  

Configuration

• Is this related to a specific tool? I see it in dotnet trace. It may nor may not affect other tools.
• What OS and version, and what distro if applicable? Linux. Reproduced on Fedora 43 and 44.
• What is the architecture (x64, x86, ARM, ARM64)? x64
• Do you know whether it is specific to that configuration?
• Are you running in any particular type of environment? root inside a VM.
• Is it a self-contained published application? No application needed. dotnet trace ps by itself demostrates the problem.
• What's the output of dotnet --info

# dotnet --info
.NET SDK:
 Version:           10.0.111
 Commit:            e2f47b0110
 Workload version:  10.0.100-manifests.330ea142
 MSBuild version:   18.0.11+e2f47b011

Runtime Environment:
 OS Name:     fedora
 OS Version:  43
 OS Platform: Linux
 RID:         fedora.43-x64
 Base Path:   /usr/lib64/dotnet/sdk/10.0.111/

.NET workloads installed:
There are no installed workloads to display.
Configured to use workload sets when installing new manifests.
No workload sets are installed. Run "dotnet workload restore" to install a workload set.

Host:
  Version:      10.0.11
  Architecture: x64
  Commit:       e2f47b0110

.NET SDKs installed:
  10.0.111 [/usr/lib64/dotnet/sdk]

.NET runtimes installed:
  Microsoft.AspNetCore.App 10.0.11 [/usr/lib64/dotnet/shared/Microsoft.AspNetCore.App]
  Microsoft.NETCore.App 10.0.11 [/usr/lib64/dotnet/shared/Microsoft.NETCore.App]

Other architectures found:
  None

Environment variables:
  DOTNET_BUNDLE_EXTRACT_BASE_DIR           [/root/.cache/dotnet_bundle_extract]
  DOTNET_ROOT                              [/usr/lib64/dotnet]

global.json file:
  Not found

Learn more:
  https://aka.ms/dotnet/info

Download .NET:
  https://aka.ms/dotnet/download

I also see this with 10.0.112

Regression?

Yes. 9.0.661903 worked.

Other information

• Please include any relevant stack traces or error messages. If possible please include text as text rather than images (so it shows up in searches).
• If you have an idea where the problem might lie, let us know that here. Please include any pointers to code, relevant changes, or related issues you know of.
• Do you know of any workarounds? Don't run as root 😄

[omajid]

Also affects dotnet dump ps.

[hoyosjs]

I think this is fixed by #5904

[omajid]

Thanks. I guess I just need to wait for a package update via nuget, then?