| Index: chrome/browser/zygote_host_linux.cc
|
| ===================================================================
|
| --- chrome/browser/zygote_host_linux.cc (revision 75653)
|
| +++ chrome/browser/zygote_host_linux.cc (working copy)
|
| @@ -1,362 +0,0 @@
|
| -// Copyright (c) 2010 The Chromium Authors. All rights reserved.
|
| -// Use of this source code is governed by a BSD-style license that can be
|
| -// found in the LICENSE file.
|
| -
|
| -#include "chrome/browser/zygote_host_linux.h"
|
| -
|
| -#include <sys/socket.h>
|
| -#include <sys/stat.h>
|
| -#include <sys/types.h>
|
| -#include <unistd.h>
|
| -
|
| -#include "base/command_line.h"
|
| -#include "base/eintr_wrapper.h"
|
| -#include "base/environment.h"
|
| -#include "base/linux_util.h"
|
| -#include "base/logging.h"
|
| -#include "base/path_service.h"
|
| -#include "base/pickle.h"
|
| -#include "base/process_util.h"
|
| -#include "base/string_number_conversions.h"
|
| -#include "base/string_util.h"
|
| -#include "base/scoped_ptr.h"
|
| -#include "base/utf_string_conversions.h"
|
| -#include "chrome/browser/renderer_host/render_sandbox_host_linux.h"
|
| -#include "chrome/common/chrome_constants.h"
|
| -#include "chrome/common/chrome_switches.h"
|
| -#include "chrome/common/process_watcher.h"
|
| -#include "chrome/common/result_codes.h"
|
| -#include "chrome/common/unix_domain_socket_posix.h"
|
| -#include "sandbox/linux/suid/suid_unsafe_environment_variables.h"
|
| -
|
| -static void SaveSUIDUnsafeEnvironmentVariables() {
|
| - // The ELF loader will clear many environment variables so we save them to
|
| - // different names here so that the SUID sandbox can resolve them for the
|
| - // renderer.
|
| -
|
| - for (unsigned i = 0; kSUIDUnsafeEnvironmentVariables[i]; ++i) {
|
| - const char* const envvar = kSUIDUnsafeEnvironmentVariables[i];
|
| - char* const saved_envvar = SandboxSavedEnvironmentVariable(envvar);
|
| - if (!saved_envvar)
|
| - continue;
|
| -
|
| - scoped_ptr<base::Environment> env(base::Environment::Create());
|
| - std::string value;
|
| - if (env->GetVar(envvar, &value))
|
| - env->SetVar(saved_envvar, value);
|
| - else
|
| - env->UnSetVar(saved_envvar);
|
| -
|
| - free(saved_envvar);
|
| - }
|
| -}
|
| -
|
| -ZygoteHost::ZygoteHost()
|
| - : control_fd_(-1),
|
| - pid_(-1),
|
| - init_(false),
|
| - using_suid_sandbox_(false),
|
| - have_read_sandbox_status_word_(false),
|
| - sandbox_status_(0) {
|
| -}
|
| -
|
| -ZygoteHost::~ZygoteHost() {
|
| - if (init_)
|
| - close(control_fd_);
|
| -}
|
| -
|
| -// static
|
| -ZygoteHost* ZygoteHost::GetInstance() {
|
| - return Singleton<ZygoteHost>::get();
|
| -}
|
| -
|
| -void ZygoteHost::Init(const std::string& sandbox_cmd) {
|
| - DCHECK(!init_);
|
| - init_ = true;
|
| -
|
| - FilePath chrome_path;
|
| - CHECK(PathService::Get(base::FILE_EXE, &chrome_path));
|
| - CommandLine cmd_line(chrome_path);
|
| -
|
| - cmd_line.AppendSwitchASCII(switches::kProcessType, switches::kZygoteProcess);
|
| -
|
| - int fds[2];
|
| - CHECK(socketpair(PF_UNIX, SOCK_SEQPACKET, 0, fds) == 0);
|
| - base::file_handle_mapping_vector fds_to_map;
|
| - fds_to_map.push_back(std::make_pair(fds[1], 3));
|
| -
|
| - const CommandLine& browser_command_line = *CommandLine::ForCurrentProcess();
|
| - if (browser_command_line.HasSwitch(switches::kZygoteCmdPrefix)) {
|
| - cmd_line.PrependWrapper(
|
| - browser_command_line.GetSwitchValueNative(switches::kZygoteCmdPrefix));
|
| - }
|
| - // Append any switches from the browser process that need to be forwarded on
|
| - // to the zygote/renderers.
|
| - // Should this list be obtained from browser_render_process_host.cc?
|
| - static const char* kForwardSwitches[] = {
|
| - switches::kAllowSandboxDebugging,
|
| - switches::kLoggingLevel,
|
| - switches::kEnableLogging, // Support, e.g., --enable-logging=stderr.
|
| - switches::kV,
|
| - switches::kVModule,
|
| - switches::kUserDataDir, // Make logs go to the right file.
|
| - // Load (in-process) Pepper plugins in-process in the zygote pre-sandbox.
|
| - switches::kRegisterPepperPlugins,
|
| - switches::kDisableSeccompSandbox,
|
| - switches::kEnableSeccompSandbox,
|
| - };
|
| - cmd_line.CopySwitchesFrom(browser_command_line, kForwardSwitches,
|
| - arraysize(kForwardSwitches));
|
| -
|
| - sandbox_binary_ = sandbox_cmd.c_str();
|
| - struct stat st;
|
| -
|
| - if (!sandbox_cmd.empty() && stat(sandbox_binary_.c_str(), &st) == 0) {
|
| - if (access(sandbox_binary_.c_str(), X_OK) == 0 &&
|
| - (st.st_uid == 0) &&
|
| - (st.st_mode & S_ISUID) &&
|
| - (st.st_mode & S_IXOTH)) {
|
| - using_suid_sandbox_ = true;
|
| - cmd_line.PrependWrapper(sandbox_binary_);
|
| -
|
| - SaveSUIDUnsafeEnvironmentVariables();
|
| - } else {
|
| - LOG(FATAL) << "The SUID sandbox helper binary was found, but is not "
|
| - "configured correctly. Rather than run without sandboxing "
|
| - "I'm aborting now. You need to make sure that "
|
| - << sandbox_binary_ << " is mode 4755 and owned by root.";
|
| - }
|
| - }
|
| -
|
| - // Start up the sandbox host process and get the file descriptor for the
|
| - // renderers to talk to it.
|
| - const int sfd = RenderSandboxHostLinux::GetInstance()->GetRendererSocket();
|
| - fds_to_map.push_back(std::make_pair(sfd, 5));
|
| -
|
| - int dummy_fd = -1;
|
| - if (using_suid_sandbox_) {
|
| - dummy_fd = socket(PF_UNIX, SOCK_DGRAM, 0);
|
| - CHECK(dummy_fd >= 0);
|
| - fds_to_map.push_back(std::make_pair(dummy_fd, 7));
|
| - }
|
| -
|
| - base::ProcessHandle process;
|
| - base::LaunchApp(cmd_line.argv(), fds_to_map, false, &process);
|
| - CHECK(process != -1) << "Failed to launch zygote process";
|
| -
|
| - if (using_suid_sandbox_) {
|
| - // In the SUID sandbox, the real zygote is forked from the sandbox.
|
| - // We need to look for it.
|
| - // But first, wait for the zygote to tell us it's running.
|
| - // The sending code is in chrome/browser/zygote_main_linux.cc.
|
| - std::vector<int> fds_vec;
|
| - const int kExpectedLength = sizeof(kZygoteMagic);
|
| - char buf[kExpectedLength];
|
| - const ssize_t len = UnixDomainSocket::RecvMsg(fds[0], buf, sizeof(buf),
|
| - &fds_vec);
|
| - CHECK(len == kExpectedLength) << "Incorrect zygote magic length";
|
| - CHECK(0 == strcmp(buf, kZygoteMagic)) << "Incorrect zygote magic";
|
| -
|
| - std::string inode_output;
|
| - ino_t inode = 0;
|
| - // Figure out the inode for |dummy_fd|, close |dummy_fd| on our end,
|
| - // and find the zygote process holding |dummy_fd|.
|
| - if (base::FileDescriptorGetInode(&inode, dummy_fd)) {
|
| - close(dummy_fd);
|
| - std::vector<std::string> get_inode_cmdline;
|
| - get_inode_cmdline.push_back(sandbox_binary_);
|
| - get_inode_cmdline.push_back(base::kFindInodeSwitch);
|
| - get_inode_cmdline.push_back(base::Int64ToString(inode));
|
| - CommandLine get_inode_cmd(get_inode_cmdline);
|
| - if (base::GetAppOutput(get_inode_cmd, &inode_output)) {
|
| - base::StringToInt(inode_output, &pid_);
|
| - }
|
| - }
|
| - CHECK(pid_ > 0) << "Did not find zygote process (using sandbox binary "
|
| - << sandbox_binary_ << ")";
|
| -
|
| - if (process != pid_) {
|
| - // Reap the sandbox.
|
| - ProcessWatcher::EnsureProcessGetsReaped(process);
|
| - }
|
| - } else {
|
| - // Not using the SUID sandbox.
|
| - pid_ = process;
|
| - }
|
| -
|
| - close(fds[1]);
|
| - control_fd_ = fds[0];
|
| -
|
| - Pickle pickle;
|
| - pickle.WriteInt(kCmdGetSandboxStatus);
|
| - std::vector<int> empty_fds;
|
| - if (!UnixDomainSocket::SendMsg(control_fd_, pickle.data(), pickle.size(),
|
| - empty_fds))
|
| - LOG(FATAL) << "Cannot communicate with zygote";
|
| - // We don't wait for the reply. We'll read it in ReadReply.
|
| -}
|
| -
|
| -ssize_t ZygoteHost::ReadReply(void* buf, size_t buf_len) {
|
| - // At startup we send a kCmdGetSandboxStatus request to the zygote, but don't
|
| - // wait for the reply. Thus, the first time that we read from the zygote, we
|
| - // get the reply to that request.
|
| - if (!have_read_sandbox_status_word_) {
|
| - if (HANDLE_EINTR(read(control_fd_, &sandbox_status_,
|
| - sizeof(sandbox_status_))) !=
|
| - sizeof(sandbox_status_)) {
|
| - return -1;
|
| - }
|
| - have_read_sandbox_status_word_ = true;
|
| - }
|
| -
|
| - return HANDLE_EINTR(read(control_fd_, buf, buf_len));
|
| -}
|
| -
|
| -pid_t ZygoteHost::ForkRenderer(
|
| - const std::vector<std::string>& argv,
|
| - const base::GlobalDescriptors::Mapping& mapping) {
|
| - DCHECK(init_);
|
| - Pickle pickle;
|
| -
|
| - pickle.WriteInt(kCmdFork);
|
| - pickle.WriteInt(argv.size());
|
| - for (std::vector<std::string>::const_iterator
|
| - i = argv.begin(); i != argv.end(); ++i)
|
| - pickle.WriteString(*i);
|
| -
|
| - pickle.WriteInt(mapping.size());
|
| -
|
| - std::vector<int> fds;
|
| - for (base::GlobalDescriptors::Mapping::const_iterator
|
| - i = mapping.begin(); i != mapping.end(); ++i) {
|
| - pickle.WriteUInt32(i->first);
|
| - fds.push_back(i->second);
|
| - }
|
| -
|
| - pid_t pid;
|
| - {
|
| - base::AutoLock lock(control_lock_);
|
| - if (!UnixDomainSocket::SendMsg(control_fd_, pickle.data(), pickle.size(),
|
| - fds))
|
| - return base::kNullProcessHandle;
|
| -
|
| - if (ReadReply(&pid, sizeof(pid)) != sizeof(pid))
|
| - return base::kNullProcessHandle;
|
| - if (pid <= 0)
|
| - return base::kNullProcessHandle;
|
| - }
|
| -
|
| - const int kRendererScore = 5;
|
| - AdjustRendererOOMScore(pid, kRendererScore);
|
| -
|
| - return pid;
|
| -}
|
| -
|
| -void ZygoteHost::AdjustRendererOOMScore(base::ProcessHandle pid, int score) {
|
| - // 1) You can't change the oom_adj of a non-dumpable process (EPERM) unless
|
| - // you're root. Because of this, we can't set the oom_adj from the browser
|
| - // process.
|
| - //
|
| - // 2) We can't set the oom_adj before entering the sandbox because the
|
| - // zygote is in the sandbox and the zygote is as critical as the browser
|
| - // process. Its oom_adj value shouldn't be changed.
|
| - //
|
| - // 3) A non-dumpable process can't even change its own oom_adj because it's
|
| - // root owned 0644. The sandboxed processes don't even have /proc, but one
|
| - // could imagine passing in a descriptor from outside.
|
| - //
|
| - // So, in the normal case, we use the SUID binary to change it for us.
|
| - // However, Fedora (and other SELinux systems) don't like us touching other
|
| - // process's oom_adj values
|
| - // (https://bugzilla.redhat.com/show_bug.cgi?id=581256).
|
| - //
|
| - // The offical way to get the SELinux mode is selinux_getenforcemode, but I
|
| - // don't want to add another library to the build as it's sure to cause
|
| - // problems with other, non-SELinux distros.
|
| - //
|
| - // So we just check for /selinux. This isn't foolproof, but it's not bad
|
| - // and it's easy.
|
| -
|
| - static bool selinux;
|
| - static bool selinux_valid = false;
|
| -
|
| - if (!selinux_valid) {
|
| - selinux = access("/selinux", X_OK) == 0;
|
| - selinux_valid = true;
|
| - }
|
| -
|
| - if (using_suid_sandbox_ && !selinux) {
|
| - base::ProcessHandle sandbox_helper_process;
|
| - std::vector<std::string> adj_oom_score_cmdline;
|
| -
|
| - adj_oom_score_cmdline.push_back(sandbox_binary_);
|
| - adj_oom_score_cmdline.push_back(base::kAdjustOOMScoreSwitch);
|
| - adj_oom_score_cmdline.push_back(base::Int64ToString(pid));
|
| - adj_oom_score_cmdline.push_back(base::IntToString(score));
|
| - CommandLine adj_oom_score_cmd(adj_oom_score_cmdline);
|
| - if (base::LaunchApp(adj_oom_score_cmd, false, true,
|
| - &sandbox_helper_process)) {
|
| - ProcessWatcher::EnsureProcessGetsReaped(sandbox_helper_process);
|
| - }
|
| - } else if (!using_suid_sandbox_) {
|
| - if (!base::AdjustOOMScore(pid, score))
|
| - PLOG(ERROR) << "Failed to adjust OOM score of renderer with pid " << pid;
|
| - }
|
| -}
|
| -
|
| -void ZygoteHost::EnsureProcessTerminated(pid_t process) {
|
| - DCHECK(init_);
|
| - Pickle pickle;
|
| -
|
| - pickle.WriteInt(kCmdReap);
|
| - pickle.WriteInt(process);
|
| -
|
| - if (HANDLE_EINTR(write(control_fd_, pickle.data(), pickle.size())) < 0)
|
| - PLOG(ERROR) << "write";
|
| -}
|
| -
|
| -base::TerminationStatus ZygoteHost::GetTerminationStatus(
|
| - base::ProcessHandle handle,
|
| - int* exit_code) {
|
| - DCHECK(init_);
|
| - Pickle pickle;
|
| - pickle.WriteInt(kCmdGetTerminationStatus);
|
| - pickle.WriteInt(handle);
|
| -
|
| - // Set this now to handle the early termination cases.
|
| - if (exit_code)
|
| - *exit_code = ResultCodes::NORMAL_EXIT;
|
| -
|
| - static const unsigned kMaxMessageLength = 128;
|
| - char buf[kMaxMessageLength];
|
| - ssize_t len;
|
| - {
|
| - base::AutoLock lock(control_lock_);
|
| - if (HANDLE_EINTR(write(control_fd_, pickle.data(), pickle.size())) < 0)
|
| - PLOG(ERROR) << "write";
|
| -
|
| - len = ReadReply(buf, sizeof(buf));
|
| - }
|
| -
|
| - if (len == -1) {
|
| - LOG(WARNING) << "Error reading message from zygote: " << errno;
|
| - return base::TERMINATION_STATUS_NORMAL_TERMINATION;
|
| - } else if (len == 0) {
|
| - LOG(WARNING) << "Socket closed prematurely.";
|
| - return base::TERMINATION_STATUS_NORMAL_TERMINATION;
|
| - }
|
| -
|
| - Pickle read_pickle(buf, len);
|
| - int status, tmp_exit_code;
|
| - void* iter = NULL;
|
| - if (!read_pickle.ReadInt(&iter, &status) ||
|
| - !read_pickle.ReadInt(&iter, &tmp_exit_code)) {
|
| - LOG(WARNING) << "Error parsing GetTerminationStatus response from zygote.";
|
| - return base::TERMINATION_STATUS_NORMAL_TERMINATION;
|
| - }
|
| -
|
| - if (exit_code)
|
| - *exit_code = tmp_exit_code;
|
| -
|
| - return static_cast<base::TerminationStatus>(status);
|
| -}
|
|
|