NetworkInterface.GetAllNetworkInterfaces() on Android leads to FileNotFoundException

[kdotdk]

Description

This has been reported previously in #3617 but problem still exists.

I have tried the following combinations:

• Works on Android 9 API 28 (Physical Tablet)
• Works on Android 10 API 29 (Visual Studio Pixel 5 Emulator, Win 10)
• Fails on Android 11 API 30 (Visual Studio Pixel 5 Emulator, Win 10)
• Fails on Android 12 API 31 (Visual Studio Pixel 5 Emulator, Win 10)
• Fails on Android 13 API 32 (Visual Studio Pixel 5 Emulator, Win 10)
• Fails on Windows 11 Windows Subsystem for Android Version 2207.40000.8.0

Steps to Reproduce

1. Get MAUI sample app

2. Add Permissions:
   [assembly: UsesPermission(Android.Manifest.Permission.AccessNetworkState)]
   [assembly: UsesPermission(Android.Manifest.Permission.ChangeNetworkState)]
   [assembly: UsesPermission(Android.Manifest.Permission.AccessWifiState)]
   [assembly: UsesPermission(Android.Manifest.Permission.ChangeWifiMulticastState)]
   [assembly: UsesPermission(Android.Manifest.Permission.ChangeWifiState)]
   [assembly: UsesPermission(Android.Manifest.Permission.Internet)]

3. Add a call to System.Net.NetworkInformation.NetworkInterface.GetAllNetworkInterfaces() on a button click (E.g. in AboutPage TabCommand)

Result the application crash with FileNotFoundException.

Link to public reproduction project repository

https://github.com/dotnet/maui-samples/tree/main/6.0/Fundamentals/Shell

Version with bug

6.0.486 (current)

Last version that worked well

Unknown/Other

Affected platforms

Android

Affected platform versions

Android 11-13 + Windows Subsystem for Android Version 2207.40000.8.0

Did you find any workaround?

No response

Relevant log output

windows-subsystem-android-crash-log.txt

I couldn't figure out the best area label to add to this issue. If you have write-permissions please help me learn by adding exactly one area label.

[jonathanpeppers]

/cc @grendello it's possible this is something in xamarin/xamarin-android

[grendello]

@jonathanpeppers it's possible, although the code that lives in xamarin/xamarin-android (and which was moved to dotnet/runtime recently) deals with enumerating interface addresses, not interfaces themselves. The code which enumerates interfaces lives in dotnet/runtime. I'll try to repro this issue and when/if I see the trace I'll be able to tell more.

[grendello]

Note that it might be due to tightened security on Android, since they have been gradually restricting access to bits and pieces of information about the system.

[kdotdk]

• Issue updated with used permissions
• Log from Windows Subsystem for Android Windows 11 added

Note first line:
10-26 08:37:07.924 4736 4736 W DOTNET_NETLINK: Failed to bind to the netlink socket. Permission denied

[grendello]

Yes, that's what it appears to be. xamarin/xamarin-android does use netlink when getifaddrs is not available in bionic (the Android libc). dotnet/runtime ported xamarin/xamarin-android getifaddrs implementation recently. getifaddrs is available (at least as a public API) on Android >= 24 (this is a compile time dependency), so if the runtime is built against an earlier version of Android API (both Xamarin.Android and dotnet/runtime are built against API 21) the netlink implementation is very likely used.

Until very recently the dotnet/runtime implementation always used the netlink implementation, with the commit linked to previously switching to the same strategy as the implementation in Xamarin.Android, to dynamically look up getifaddrs and, if found, use that instead of the netlink code. This fix might be required for the enumeration to work on Android 30 and above.

/cc @simonrozsival was your fix above backported to net6? Or is it going to be part of only net7+?

Tagging subscribers to 'arch-android': @steveisok, @akoeplinger
See info in area-owners.md if you want to be subscribed.

Issue Details

---

Description

This has been reported previously in #3617 but problem still exists.

I have tried the following combinations:

• Works on Android 9 API 28 (Physical Tablet)
• Works on Android 10 API 29 (Visual Studio Pixel 5 Emulator, Win 10)
• Fails on Android 11 API 30 (Visual Studio Pixel 5 Emulator, Win 10)
• Fails on Android 12 API 31 (Visual Studio Pixel 5 Emulator, Win 10)
• Fails on Android 13 API 32 (Visual Studio Pixel 5 Emulator, Win 10)
• Fails on Windows 11 Windows Subsystem for Android Version 2207.40000.8.0

Steps to Reproduce

1. Get MAUI sample app

2. Add Permissions:
   [assembly: UsesPermission(Android.Manifest.Permission.AccessNetworkState)]
   [assembly: UsesPermission(Android.Manifest.Permission.ChangeNetworkState)]
   [assembly: UsesPermission(Android.Manifest.Permission.AccessWifiState)]
   [assembly: UsesPermission(Android.Manifest.Permission.ChangeWifiMulticastState)]
   [assembly: UsesPermission(Android.Manifest.Permission.ChangeWifiState)]
   [assembly: UsesPermission(Android.Manifest.Permission.Internet)]

3. Add a call to System.Net.NetworkInformation.NetworkInterface.GetAllNetworkInterfaces() on a button click (E.g. in AboutPage TabCommand)

Result the application crash with FileNotFoundException.

Link to public reproduction project repository

https://github.com/dotnet/maui-samples/tree/main/6.0/Fundamentals/Shell

Version with bug

6.0.486 (current)

Last version that worked well

Unknown/Other

Affected platforms

Android

Affected platform versions

Android 11-13 + Windows Subsystem for Android Version 2207.40000.8.0

Did you find any workaround?

No response

Relevant log output

windows-subsystem-android-crash-log.txt

Author:	kdotdk
Assignees:	-
Labels:	os-android, untriaged
Milestone:	-

Tagging subscribers to this area: @dotnet/ncl
See info in area-owners.md if you want to be subscribed.

Issue Details

---

Description

This has been reported previously in #3617 but problem still exists.

I have tried the following combinations:

• Works on Android 9 API 28 (Physical Tablet)
• Works on Android 10 API 29 (Visual Studio Pixel 5 Emulator, Win 10)
• Fails on Android 11 API 30 (Visual Studio Pixel 5 Emulator, Win 10)
• Fails on Android 12 API 31 (Visual Studio Pixel 5 Emulator, Win 10)
• Fails on Android 13 API 32 (Visual Studio Pixel 5 Emulator, Win 10)
• Fails on Windows 11 Windows Subsystem for Android Version 2207.40000.8.0

Steps to Reproduce

1. Get MAUI sample app

2. Add Permissions:
   [assembly: UsesPermission(Android.Manifest.Permission.AccessNetworkState)]
   [assembly: UsesPermission(Android.Manifest.Permission.ChangeNetworkState)]
   [assembly: UsesPermission(Android.Manifest.Permission.AccessWifiState)]
   [assembly: UsesPermission(Android.Manifest.Permission.ChangeWifiMulticastState)]
   [assembly: UsesPermission(Android.Manifest.Permission.ChangeWifiState)]
   [assembly: UsesPermission(Android.Manifest.Permission.Internet)]

3. Add a call to System.Net.NetworkInformation.NetworkInterface.GetAllNetworkInterfaces() on a button click (E.g. in AboutPage TabCommand)

Result the application crash with FileNotFoundException.

Link to public reproduction project repository

https://github.com/dotnet/maui-samples/tree/main/6.0/Fundamentals/Shell

Version with bug

6.0.486 (current)

Last version that worked well

Unknown/Other

Affected platforms

Android

Affected platform versions

Android 11-13 + Windows Subsystem for Android Version 2207.40000.8.0

Did you find any workaround?

No response

Relevant log output

windows-subsystem-android-crash-log.txt

Author:	kdotdk
Assignees:	-
Labels:	area-System.Net, os-android, untriaged
Milestone:	-

[simonrozsival]

@grendello the most recent fix should be included in a servicing release of .NET 6 soon: #77260

[kdotdk]

Have tried with new .Net 6.0.12.
It works on Android 11 API 30 (Visual Studio Pixel 5 Emulator, Win 10) 👍
(I have not access to Physical Android Device )

[akoeplinger]

Thanks for the feedback and great to hear it works now! I assume we can close this issue then or is there something left?