Enable Binder IPC on RedHat Linux (RHEL/CentOS/Fedora)

⚠️ Important Notice This document is generated by GitHub Copilot and has not been fully tested or validated in real RedHat-based environments. The instructions provided are based on general knowledge and may require adjustments for your specific system configuration. Please proceed with caution and test thoroughly in a safe environment before applying to production systems.

RedHat-based distributions (RHEL, CentOS, Fedora) do not include Binder IPC support by default. Here are methods to enable it:

Fedora

Fedora provides kernel source packages that can be modified to include binder support:

# Install development tools
$ sudo dnf groupinstall "Development Tools"
$ sudo dnf install fedora-packager fedpkg
$ sudo dnf install kernel-devel kernel-headers

# Install kernel build dependencies
$ sudo dnf builddep kernel

# Get kernel source
$ fedpkg clone -a kernel
$ cd kernel
$ fedpkg switch-branch f$(rpm -E %fedora)
$ fedpkg prep

# Modify kernel config to enable binder
$ cd ~/rpmbuild/BUILD/kernel-*/linux-*
$ make menuconfig

# Enable the following options:
# General setup -> Android support (CONFIG_ANDROID=y)
# CONFIG_ANDROID_BINDER_IPC=y
# CONFIG_ANDROID_BINDERFS=y
# CONFIG_ASHMEM=y

# Build the kernel
$ make -j$(nproc)
$ sudo make modules_install
$ sudo make install

# Update bootloader
$ sudo grub2-mkconfig -o /boot/grub2/grub.cfg
$ sudo reboot

Method 2: Third-party Kernel Modules

Some third-party repositories may provide binder modules:

# Enable RPM Fusion repositories
$ sudo dnf install https://mirrors.rpmfusion.org/free/fedora/rpmfusion-free-release-$(rpm -E %fedora).noarch.rpm

# Look for available binder-related packages
$ dnf search binder android-tools

RHEL/CentOS

Method 1: Build Custom Kernel

For enterprise distributions, building a custom kernel is often the most reliable approach:

# Install EPEL repository (CentOS/RHEL 8+)
$ sudo dnf install epel-release

# Install development tools
$ sudo dnf groupinstall "Development Tools"
$ sudo dnf install rpm-build rpm-devel libtool

# Install kernel build dependencies
$ sudo dnf install kernel-devel kernel-headers
$ sudo dnf install elfutils-libelf-devel openssl-devel

# Download kernel source matching your running kernel
$ KERNEL_VERSION=$(uname -r | sed 's/\.el.*$//')
$ wget https://cdn.kernel.org/pub/linux/kernel/v5.x/linux-${KERNEL_VERSION}.tar.xz
$ tar -xf linux-${KERNEL_VERSION}.tar.xz
$ cd linux-${KERNEL_VERSION}

# Use current kernel config as base
$ zcat /proc/config.gz > .config
# or
$ cp /boot/config-$(uname -r) .config

# Modify config to enable binder
$ make menuconfig
# Enable CONFIG_ANDROID=y, CONFIG_ANDROID_BINDER_IPC=y, CONFIG_ANDROID_BINDERFS=y

# Build and install
$ make -j$(nproc)
$ sudo make modules_install
$ sudo make install

# Update GRUB
$ sudo grub2-mkconfig -o /boot/grub2/grub.cfg
$ sudo reboot

Method 2: Using ELRepo (CentOS/RHEL)

ELRepo sometimes provides additional kernel modules:

# Install ELRepo
$ sudo rpm --import https://www.elrepo.org/RPM-GPG-KEY-elrepo.org
$ sudo dnf install https://www.elrepo.org/elrepo-release-8.el8.elrepo.noarch.rpm

# Search for kernel modules
$ dnf --enablerepo=elrepo search kernel-ml

CentOS Stream

CentOS Stream may have more recent kernels that could include binder support:

# Check current kernel version
$ uname -r

# Update to latest kernel
$ sudo dnf update kernel

# Check if binder is already available
$ grep -E "(ANDROID|BINDER)" /boot/config-$(uname -r)

Alternative: Container-based Approach

If kernel modification is not feasible, consider using containers:

# Install Podman (RedHat's container runtime)
$ sudo dnf install podman

# Run rsbinder applications in a container with custom kernel
# This requires a base image with binder support

Module Loading (After Kernel Build)

Once you have a kernel with binder support:

# Load binder modules
$ sudo modprobe binder_linux devices="binder,hwbinder,vndbinder"

# Verify modules are loaded
$ lsmod | grep binder

# Create persistent module loading
$ echo "binder_linux" | sudo tee /etc/modules-load.d/binder.conf

# Set module parameters
$ echo "options binder_linux devices=binder,hwbinder,vndbinder" | sudo tee /etc/modprobe.d/binder.conf

SELinux Considerations

RedHat systems use SELinux which may interfere with binder operations:

# Check SELinux status
$ sestatus

# Temporarily disable SELinux for testing
$ sudo setenforce 0

# Create SELinux policy for binder (advanced)
# This requires creating custom SELinux policies for binder devices

Verification

Test that binder is working:

# Check if binderfs is available
$ grep binderfs /proc/filesystems

# Create test binder device
$ sudo mkdir -p /dev/binderfs
$ sudo mount -t binder binder /dev/binderfs
$ sudo rsb_device test_device

# Check device creation
$ ls -la /dev/binderfs/

Troubleshooting

Common Issues:

  1. Module compilation fails: Ensure all kernel-devel packages match your running kernel
  2. SELinux denials: Check audit.log for SELinux denials and create appropriate policies
  3. Kernel version mismatch: Ensure kernel source matches your running kernel version

Debugging:

# Check kernel messages
$ dmesg | grep -i binder

# Check system journal
$ journalctl -f | grep -i binder

# Verify kernel config
$ grep -E "(ANDROID|BINDER)" /boot/config-$(uname -r)

References