From 44a514543530626a968c2a3e782a33fa30ef381d Mon Sep 17 00:00:00 2001
From: Matthias Braun <matze@braunis.de>
Date: Fri, 7 Jul 2017 18:53:24 +0000
Subject: [PATCH] FuzzerUtilDarwin.cpp: We need to pass modifiable strings to
 posix_spawn

This fixes a bug where unmodifiable strings where passed to posix_spawn.

This is an attempt to unbreak the greendragon libFuzzer bot.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@307424 91177308-0d34-0410-b5e6-96231b3b80d8
---
 lib/Fuzzer/FuzzerUtilDarwin.cpp | 13 +++++++++++--
 1 file changed, 11 insertions(+), 2 deletions(-)

diff --git a/lib/Fuzzer/FuzzerUtilDarwin.cpp b/lib/Fuzzer/FuzzerUtilDarwin.cpp
index 9674368c355..2df4872a920 100644
--- a/lib/Fuzzer/FuzzerUtilDarwin.cpp
+++ b/lib/Fuzzer/FuzzerUtilDarwin.cpp
@@ -15,6 +15,8 @@
 #include <mutex>
 #include <signal.h>
 #include <spawn.h>
+#include <stdlib.h>
+#include <string.h>
 #include <sys/wait.h>
 
 // There is no header for this on macOS so declare here
@@ -97,11 +99,16 @@ int ExecuteCommand(const std::string &Command) {
   pid_t Pid;
   char **Environ = environ; // Read from global
   const char *CommandCStr = Command.c_str();
-  const char *Argv[] = {"sh", "-c", CommandCStr, NULL};
+  char *const Argv[] = {
+    strdup("sh"),
+    strdup("-c"),
+    strdup(CommandCStr),
+    NULL
+  };
   int ErrorCode = 0, ProcessStatus = 0;
   // FIXME: We probably shouldn't hardcode the shell path.
   ErrorCode = posix_spawn(&Pid, "/bin/sh", NULL, &SpawnAttributes,
-                          (char *const *)Argv, Environ);
+                          Argv, Environ);
   (void)posix_spawnattr_destroy(&SpawnAttributes);
   if (!ErrorCode) {
     pid_t SavedPid = Pid;
@@ -120,6 +127,8 @@ int ExecuteCommand(const std::string &Command) {
     // Shell execution failure.
     ProcessStatus = W_EXITCODE(127, 0);
   }
+  for (unsigned i = 0, n = sizeof(Argv) / sizeof(Argv[0]); i < n; ++i)
+    free(Argv[i]);
 
   // Restore the signal handlers of the current process when the last thread
   // using this function finishes.