Merge "first_stage_init: add console" am: ee148dd9c1 (d03cc300) · Commits · e / os / android_system_core

init/Android.bp

+3 −0

Original line number	Diff line number	Diff line
		@@ -26,6 +26,7 @@ cc_defaults {
		"-Wextra",
		"-Wno-unused-parameter",
		"-Werror",
		"-DALLOW_FIRST_STAGE_CONSOLE=0",
		"-DALLOW_LOCAL_PROP_OVERRIDE=0",
		"-DALLOW_PERMISSIVE_SELINUX=0",
		"-DREBOOT_BOOTLOADER_ON_PANIC=0",
		@@ -36,6 +37,8 @@ cc_defaults {
		product_variables: {
		debuggable: {
		cppflags: [
		"-UALLOW_FIRST_STAGE_CONSOLE",
		"-DALLOW_FIRST_STAGE_CONSOLE=1",
		"-UALLOW_LOCAL_PROP_OVERRIDE",
		"-DALLOW_LOCAL_PROP_OVERRIDE=1",
		"-UALLOW_PERMISSIVE_SELINUX",

init/Android.mk

+2 −0

Original line number	Diff line number	Diff line
		@@ -8,6 +8,7 @@ LOCAL_PATH:= $(call my-dir)

		ifneq (,$(filter userdebug eng,$(TARGET_BUILD_VARIANT)))
		init_options += \
		-DALLOW_FIRST_STAGE_CONSOLE=1 \
		-DALLOW_LOCAL_PROP_OVERRIDE=1 \
		-DALLOW_PERMISSIVE_SELINUX=1 \
		-DREBOOT_BOOTLOADER_ON_PANIC=1 \
		@@ -15,6 +16,7 @@ init_options += \
		-DDUMP_ON_UMOUNT_FAILURE=1
		else
		init_options += \
		-DALLOW_FIRST_STAGE_CONSOLE=0 \
		-DALLOW_LOCAL_PROP_OVERRIDE=0 \
		-DALLOW_PERMISSIVE_SELINUX=0 \
		-DREBOOT_BOOTLOADER_ON_PANIC=0 \

init/first_stage_init.cpp

+53 −4

Original line number	Diff line number	Diff line
		@@ -24,10 +24,12 @@
		#include <sys/stat.h>
		#include <sys/sysmacros.h>
		#include <sys/types.h>
		#include <sys/wait.h>
		#include <unistd.h>

		#include <filesystem>
		#include <string>
		#include <thread>
		#include <vector>

		#include <android-base/chrono_utils.h>
		@@ -92,9 +94,50 @@ void FreeRamdisk(DIR* dir, dev_t dev) {
		}
		}

		bool ForceNormalBoot() {
		std::string cmdline;
		android::base::ReadFileToString("/proc/cmdline", &cmdline);
		void StartConsole() {
		if (mknod("/dev/console", S_IFCHR \| 0600, makedev(5, 1))) {
		PLOG(ERROR) << "unable to create /dev/console";
		return;
		}
		pid_t pid = fork();
		if (pid != 0) {
		int status;
		waitpid(pid, &status, 0);
		LOG(ERROR) << "console shell exited with status " << status;
		return;
		}
		int fd = -1;
		int tries = 10;
		// The device driver for console may not be ready yet so retry for a while in case of failure.
		while (tries--) {
		fd = open("/dev/console", O_RDWR);
		if (fd != -1) {
		break;
		}
		std::this_thread::sleep_for(100ms);
		}
		if (fd == -1) {
		LOG(ERROR) << "Could not open /dev/console, errno = " << errno;
		_exit(127);
		}
		ioctl(fd, TIOCSCTTY, 0);
		dup2(fd, 0);
		dup2(fd, 1);
		dup2(fd, 2);
		close(fd);

		const char* path = "/system/bin/sh";
		const char* args[] = {path, nullptr};
		int rv = execv(path, const_cast<char**>(args));
		LOG(ERROR) << "unable to execv, returned " << rv << " errno " << errno;
		_exit(127);
		}

		bool FirstStageConsole(const std::string& cmdline) {
		return cmdline.find("androidboot.first_stage_console=1") != std::string::npos;
		}

		bool ForceNormalBoot(const std::string& cmdline) {
		return cmdline.find("androidboot.force_normal_boot=1") != std::string::npos;
		}

		@@ -127,6 +170,8 @@ int FirstStageMain(int argc, char** argv) {
		#undef MAKE_STR
		// Don't expose the raw commandline to unprivileged processes.
		CHECKCALL(chmod("/proc/cmdline", 0440));
		std::string cmdline;
		android::base::ReadFileToString("/proc/cmdline", &cmdline);
		gid_t groups[] = {AID_READPROC};
		CHECKCALL(setgroups(arraysize(groups), groups));
		CHECKCALL(mount("sysfs", "/sys", "sysfs", 0, NULL));
		@@ -198,7 +243,11 @@ int FirstStageMain(int argc, char** argv) {
		LOG(FATAL) << "Failed to load kernel modules";
		}

		if (ForceNormalBoot()) {
		if (ALLOW_FIRST_STAGE_CONSOLE && FirstStageConsole(cmdline)) {
		StartConsole();
		}

		if (ForceNormalBoot(cmdline)) {
		mkdir("/first_stage_ramdisk", 0755);
		// SwitchRoot() must be called with a mount point as the target, so we bind mount the
		// target directory to itself here.