Print a better error message (links to doc) on SUID sandbox problems.

content/browser/zygote_host/zygote_host_impl_linux.cc

 // Copyright (c) 2012 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 "content/browser/zygote_host/zygote_host_impl_linux.h"
 
 #include <sys/socket.h>
 #include <sys/stat.h>
 #include <sys/types.h>
 #include <unistd.h>
@@ skipping 109 matching lines @@
 
   sandbox_binary_ = sandbox_cmd.c_str();
 
   // A non empty sandbox_cmd means we want a SUID sandbox.
   using_suid_sandbox_ = !sandbox_cmd.empty();
 
   if (using_suid_sandbox_) {
     struct stat st;
     if (stat(sandbox_binary_.c_str(), &st) != 0) {
       LOG(FATAL) << "The SUID sandbox helper binary is missing: "
-                 << sandbox_binary_ << " Aborting now.";
+                 << sandbox_binary_ << " Aborting now. "
+                 << "See https://code.google.com/p/chromium/wiki/LinuxSUIDSandbox "

[Lei Zhang, 2013/09/12 01:07:31]

Maybe just add a helper function instead of repeating yourself and going over 80
chars/line?

void WriteFatalMessage(const std::string& msg) {
  LOG(FATAL) << msg
             << " See ...";

+                 << "and https://code.google.com/p/chromium/wiki/LinuxSUIDSandboxDevelopment "
+                 << "for more info.";
     }
 
     if (access(sandbox_binary_.c_str(), X_OK) == 0 &&
         (st.st_uid == 0) &&
         (st.st_mode & S_ISUID) &&
         (st.st_mode & S_IXOTH)) {
       cmd_line.PrependWrapper(sandbox_binary_);
 
       scoped_ptr<sandbox::SetuidSandboxClient>
           sandbox_client(sandbox::SetuidSandboxClient::Create());
       sandbox_client->SetupLaunchEnvironment();
     } 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 owned by root and has mode 4755.";
+                 << sandbox_binary_ << " is owned by root and has mode 4755. "
+                 << "See https://code.google.com/p/chromium/wiki/LinuxSUIDSandbox "
+                 << "and https://code.google.com/p/chromium/wiki/LinuxSUIDSandboxDevelopment "
+                 << "for more info.";
     }
   }
 
   // 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, GetSandboxFD()));
 
   int dummy_fd = -1;
   if (using_suid_sandbox_) {
@@ skipping 349 matching lines @@
   return RenderSandboxHostLinux::GetInstance()->pid();
 }
 
 int ZygoteHostImpl::GetSandboxStatus() const {
   if (have_read_sandbox_status_word_)
     return sandbox_status_;
   return 0;
 }
 
 }  // namespace content