From df3af446e7d9d42230a2ec71984ee19260af5c66 Mon Sep 17 00:00:00 2001
From: Simon <simon@bitcartel.com>
Date: Fri, 26 Aug 2016 23:35:45 -0700
Subject: [PATCH 1/2] Fixes #1122 where json_spirit could stack overflow
 because there was no maximum limit set on the number of nested compound
 elements.

---
 src/Makefile.gtest.include             |  1 +
 src/gtest/test_jsonspirit.cpp          | 17 +++++++++++++++++
 src/json/json_spirit_reader_template.h |  6 ++++++
 3 files changed, 24 insertions(+)
 create mode 100644 src/gtest/test_jsonspirit.cpp

diff --git a/src/Makefile.gtest.include b/src/Makefile.gtest.include
index 8e22ed397..388c7697c 100644
--- a/src/Makefile.gtest.include
+++ b/src/Makefile.gtest.include
@@ -5,6 +5,7 @@ bin_PROGRAMS += zcash-gtest
 zcash_gtest_SOURCES = \
 	gtest/main.cpp \
 	gtest/json_test_vectors.cpp \
+	gtest/test_jsonspirit.cpp \
 	gtest/test_tautology.cpp \
 	gtest/test_checktransaction.cpp \
 	gtest/test_equihash.cpp \
diff --git a/src/gtest/test_jsonspirit.cpp b/src/gtest/test_jsonspirit.cpp
new file mode 100644
index 000000000..f93e8d459
--- /dev/null
+++ b/src/gtest/test_jsonspirit.cpp
@@ -0,0 +1,17 @@
+#include <gtest/gtest.h>
+
+#include "json/json_spirit_reader_template.h"
+
+using namespace json_spirit;
+
+// This test checks if we have fixed a stack overflow problem with json_spirit.
+// It was possible to try and create an unlimited number of nested compound elements.
+// Without the fix in json_spirit_reader_template.h, this test will segfault.
+TEST(json_spirit_tests, nested_input_segfault) {
+    std::vector<char> v (100000);
+    std::fill (v.begin(),v.end(), '[');
+    std::string s(v.begin(), v.end());
+    Value value;
+    bool b = json_spirit::read_string(s, value);
+    ASSERT_FALSE(b);
+}
diff --git a/src/json/json_spirit_reader_template.h b/src/json/json_spirit_reader_template.h
index 47e3c1ca8..2e3d21e90 100644
--- a/src/json/json_spirit_reader_template.h
+++ b/src/json/json_spirit_reader_template.h
@@ -308,6 +308,12 @@ namespace json_spirit
             }
             else
             {
+                // ZCASH: Prevent potential stack overflow by setting a limit on the number of nested compound elements
+                if (stack_.size() > 128) {
+                    throw "too many nested elements";
+                }
+                // ENDZCASH
+
                 stack_.push_back( current_p_ );
 
                 Array_or_obj new_array_or_obj;   // avoid copy by building new array or object in place

From 1f882153b69d05c7fd0890981b7f6fff172c4795 Mon Sep 17 00:00:00 2001
From: Simon <simon@bitcartel.com>
Date: Sat, 27 Aug 2016 09:14:25 -0700
Subject: [PATCH 2/2] Throw a domain error as json_spirit is a third-party
 library.

---
 src/json/json_spirit_reader_template.h | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/src/json/json_spirit_reader_template.h b/src/json/json_spirit_reader_template.h
index 2e3d21e90..33aa0958e 100644
--- a/src/json/json_spirit_reader_template.h
+++ b/src/json/json_spirit_reader_template.h
@@ -310,7 +310,7 @@ namespace json_spirit
             {
                 // ZCASH: Prevent potential stack overflow by setting a limit on the number of nested compound elements
                 if (stack_.size() > 128) {
-                    throw "too many nested elements";
+                    throw std::domain_error("too many nested elements");
                 }
                 // ENDZCASH