Go: x/mobile: Calling net.InterfaceAddrs() fails on Android SDK 30

Created on 4 Aug 2020 · 4Comments · Source: golang/go

What version of Go are you using (`go version`)?

$ go version
go version go1.14.6 darwin/amd64

$gomobile version
gomobile version +973feb4 Sat Aug 1 11:21:45 2020 +0000 (android,ios); androidSDK=/sdk/platforms/android-30

Does this issue reproduce with the latest release?

Yes

What operating system and processor architecture are you using (`go env`)?

go env Output



$ go env

GO111MODULE="on"

GOARCH="amd64"

GOBIN=""

GOCACHE="/Users/user/Library/Caches/go-build"

GOENV="/Users/user/Library/Application Support/go/env"

GOEXE=""

GOFLAGS=""

GOHOSTARCH="amd64"

GOHOSTOS="darwin"

GOINSECURE=""

GONOPROXY=""

GONOSUMDB=""

GOOS="darwin"

GOPATH="/Users/user/golang"

GOPRIVATE=""

GOPROXY="https://proxy.golang.org,direct"

GOROOT="/usr/local/Cellar/go/1.14.6/libexec"

GOSUMDB="sum.golang.org"

GOTMPDIR=""

GOTOOLDIR="/usr/local/Cellar/go/1.14.6/libexec/pkg/tool/darwin_amd64"

GCCGO="gccgo"

AR="ar"

CC="clang"

CXX="clang++"

CGO_ENABLED="1"

GOMOD="/Users/user/golang/src/golang.org/x/mobile/go.mod"

CGO_CFLAGS="-g -O2"

CGO_CPPFLAGS=""

CGO_CXXFLAGS="-g -O2"

CGO_FFLAGS="-g -O2"

CGO_LDFLAGS="-g -O2"

PKG_CONFIG="pkg-config"

GOGCCFLAGS="-fPIC -m64 -pthread -fno-caret-diagnostics -Qunused-arguments -fmessage-length=0 -fdebug-prefix-map=/var/folders/kq/3436m_v11sg0l7zqtmv2r1gw0000gn/T/go-build713467523=/tmp/go-build -gno-record-gcc-switches -fno-common"

What did you do?

Calling net.InterfaceAddrs() fails on Android app targetting SDK version 30. With build.gradle looking like:

android {
    compileSdkVersion 30
    buildToolsVersion "30.0.0"
    defaultConfig {
        applicationId "com.example.testapp"
        minSdkVersion 29
        targetSdkVersion 30
        versionCode 1
        versionName "1.0"
        testInstrumentationRunner "androidx.test.runner.AndroidJUnitRunner"
    }
    buildTypes {
        release {
            minifyEnabled false
            proguardFiles getDefaultProguardFile('proguard-android-optimize.txt'), 'proguard-rules.pro'
        }
    }
}

Building the exact same app targetting SDK 29 works, and returns no error:

android {
    compileSdkVersion 30
    buildToolsVersion "30.0.0"
    defaultConfig {
        applicationId "com.example.testapp"
        minSdkVersion 29
        targetSdkVersion 29
        versionCode 1
        versionName "1.0"
        testInstrumentationRunner "androidx.test.runner.AndroidJUnitRunner"
    }
    buildTypes {
        release {
            minifyEnabled false
            proguardFiles getDefaultProguardFile('proguard-android-optimize.txt'), 'proguard-rules.pro'
        }
    }
}

What did you expect to see?

Targetting SDK 30 would behave no differently.

What did you see instead?

Calling net.InterfaceAddrs() results in error route ip+net: netlinkrib: permission denied when embedded in Android app targetting SDK 30 (R):

2020-08-04 15:10:21.386 15754-15754/? W/Thread-2: type=1400 audit(0.0:616): avc: denied { bind } for scontext=u:r:untrusted_app:s0:c158,c256,c512,c768 tcontext=u:r:untrusted_app:s0:c158,c256,c512,c768 tclass=netlink_route_socket permissive=0 b/155595000 app=com.example.testapp

NeedsInvestigation mobile

Source