From c44587a70cbae0985c7e4cc5c231af88c0d20331 Mon Sep 17 00:00:00 2001
From: Tatsuhiro Tsujikawa <tatsuhiro.t@gmail.com>
Date: Thu, 24 Sep 2015 23:57:24 +0900
Subject: [PATCH] nghttpx: Use _Exit when exiting from child process

---
 src/shrpx.cc                    | 14 ++++++++------
 src/shrpx.h                     |  2 +-
 src/shrpx_connection_handler.cc |  6 +++---
 src/shrpx_ssl.cc                |  6 ++++--
 4 files changed, 16 insertions(+), 12 deletions(-)

diff --git a/src/shrpx.cc b/src/shrpx.cc
index 57d546e4..a4e64ccc 100644
--- a/src/shrpx.cc
+++ b/src/shrpx.cc
@@ -244,6 +244,8 @@ void exec_binary(SignalServer *ssv) {
     return;
   }
 
+  // child process
+
   shrpx_signal_unset_master_proc_ign_handler();
 
   rv = shrpx_signal_unblock_all();
@@ -251,7 +253,7 @@ void exec_binary(SignalServer *ssv) {
     auto error = errno;
     LOG(ERROR) << "Unblocking all signals failed: " << strerror(error);
 
-    exit(EXIT_FAILURE);
+    _Exit(EXIT_FAILURE);
   }
 
   auto exec_path = util::get_exec_path(get_config()->argc, get_config()->argv,
@@ -259,7 +261,7 @@ void exec_binary(SignalServer *ssv) {
 
   if (!exec_path) {
     LOG(ERROR) << "Could not resolve the executable path";
-    exit(EXIT_FAILURE);
+    _Exit(EXIT_FAILURE);
   }
 
   auto argv = make_unique<char *[]>(get_config()->argc + 1);
@@ -336,7 +338,7 @@ void exec_binary(SignalServer *ssv) {
   if (execve(argv[0], argv.get(), envp.get()) == -1) {
     auto error = errno;
     LOG(ERROR) << "execve failed: errno=" << error;
-    exit(EXIT_FAILURE);
+    _Exit(EXIT_FAILURE);
   }
 }
 } // namespace
@@ -699,7 +701,7 @@ pid_t fork_worker_process(SignalServer *ssv) {
       auto error = errno;
       LOG(FATAL) << "Unblocking all signals failed: " << strerror(error);
 
-      exit(EXIT_FAILURE);
+      _Exit(EXIT_FAILURE);
     }
 
     close(ssv->ipc_fd[1]);
@@ -708,10 +710,10 @@ pid_t fork_worker_process(SignalServer *ssv) {
     if (rv != 0) {
       LOG(FATAL) << "Worker process returned error";
 
-      exit(EXIT_FAILURE);
+      _Exit(EXIT_FAILURE);
     }
 
-    exit(EXIT_SUCCESS);
+    _Exit(EXIT_SUCCESS);
   }
 
   // parent process
diff --git a/src/shrpx.h b/src/shrpx.h
index e2a99b3d..dfc52701 100644
--- a/src/shrpx.h
+++ b/src/shrpx.h
@@ -42,6 +42,6 @@
 #define _Exit(status) _exit(status)
 #endif // !HAVE__EXIT
 
-#define DIE() exit(EXIT_FAILURE)
+#define DIE() _Exit(EXIT_FAILURE)
 
 #endif // SHRPX_H
diff --git a/src/shrpx_connection_handler.cc b/src/shrpx_connection_handler.cc
index 5610b06b..167ecc19 100644
--- a/src/shrpx_connection_handler.cc
+++ b/src/shrpx_connection_handler.cc
@@ -454,7 +454,7 @@ int ConnectionHandler::start_ocsp_update(const char *cert_file) {
       auto error = errno;
       LOG(FATAL) << "Unblocking all signals failed: " << strerror(error);
 
-      exit(EXIT_FAILURE);
+      _Exit(EXIT_FAILURE);
     }
 
     dup2(pfd[1], 1);
@@ -465,7 +465,7 @@ int ConnectionHandler::start_ocsp_update(const char *cert_file) {
       auto error = errno;
       LOG(ERROR) << "Could not execute ocsp query command: " << argv[0]
                  << ", execve() faild, errno=" << error;
-      exit(EXIT_FAILURE);
+      _Exit(EXIT_FAILURE);
     }
     // unreachable
   }
@@ -482,7 +482,7 @@ int ConnectionHandler::start_ocsp_update(const char *cert_file) {
     auto error = errno;
     LOG(FATAL) << "Restoring all signals failed: " << strerror(error);
 
-    exit(EXIT_FAILURE);
+    _Exit(EXIT_FAILURE);
   }
 
   if (pid == -1) {
diff --git a/src/shrpx_ssl.cc b/src/shrpx_ssl.cc
index aa35d50c..dc85b43e 100644
--- a/src/shrpx_ssl.cc
+++ b/src/shrpx_ssl.cc
@@ -88,6 +88,8 @@ int verify_callback(int preverify_ok, X509_STORE_CTX *ctx) {
 }
 } // namespace
 
+// This function is meant be called from master process, hence the
+// call exit(3).
 std::vector<unsigned char>
 set_alpn_prefs(const std::vector<std::string> &protos) {
   size_t len = 0;
@@ -95,7 +97,7 @@ set_alpn_prefs(const std::vector<std::string> &protos) {
   for (const auto &proto : protos) {
     if (proto.size() > 255) {
       LOG(FATAL) << "Too long ALPN identifier: " << proto.size();
-      DIE();
+      exit(EXIT_FAILURE);
     }
 
     len += 1 + proto.size();
@@ -103,7 +105,7 @@ set_alpn_prefs(const std::vector<std::string> &protos) {
 
   if (len > (1 << 16) - 1) {
     LOG(FATAL) << "Too long ALPN identifier list: " << len;
-    DIE();
+    exit(EXIT_FAILURE);
   }
 
   auto out = std::vector<unsigned char>(len);