Added generic secure JIT support for RandomX.

CMakeLists.txt

@@ -1,4 +1,4 @@
-cmake_minimum_required(VERSION 2.8)
+cmake_minimum_required(VERSION 2.8.12)
 project(xmrig)
 
 option(WITH_HWLOC           "Enable hwloc support" ON)
@@ -25,6 +25,7 @@ option(WITH_INTERLEAVE_DEBUG_LOG "Enable debug log for threads interleave" OFF)
 option(WITH_PROFILING       "Enable profiling for developers" OFF)
 option(WITH_SSE4_1          "Enable SSE 4.1 for Blake2" ON)
 option(WITH_BENCHMARK       "Enable builtin RandomX benchmark and stress test" ON)
+option(WITH_SECURE_JIT      "Enable secure access to JIT memory" OFF)
 
 option(BUILD_STATIC         "Build static binary" OFF)
 option(ARM_TARGET           "Force use specific ARM target 8 or 7" 0)

cmake/os.cmake

@@ -32,6 +32,10 @@ elseif(XMRIG_OS_APPLE)
     else()
         add_definitions(/DXMRIG_OS_MACOS)
     endif()
+
+    if (XMRIG_ARM)
+        set(WITH_SECURE_JIT ON)
+    endif()
 elseif(XMRIG_OS_UNIX)
     add_definitions(/DXMRIG_OS_UNIX)
 
@@ -43,3 +47,7 @@ elseif(XMRIG_OS_UNIX)
         add_definitions(/DXMRIG_OS_FREEBSD)
     endif()
 endif()
+
+if (WITH_SECURE_JIT)
+    add_definitions(/DXMRIG_SECURE_JIT)
+endif()

src/3rdparty/argon2/CMakeLists.txt

@@ -1,4 +1,4 @@
-cmake_minimum_required(VERSION 2.8)
+cmake_minimum_required(VERSION 2.8.12)
 
 project(argon2 C)
 set(CMAKE_C_STANDARD 99)

src/3rdparty/libethash/CMakeLists.txt

@@ -1,4 +1,4 @@
-cmake_minimum_required (VERSION 2.8)
+cmake_minimum_required (VERSION 2.8.12)
 project (ethash C)
 
 set(CMAKE_C_FLAGS_RELEASE "${CMAKE_C_FLAGS_RELEASE} -Os")

src/backend/cpu/platform/BasicCpuInfo_arm.cpp

@@ -36,12 +36,14 @@
 #include "3rdparty/rapidjson/document.h"
 
 
-#ifdef XMRIG_OS_UNIX
+#if defined(XMRIG_OS_UNIX)
 namespace xmrig {
 
 extern String cpu_name_arm();
 
 } // namespace xmrig
+#elif defined(XMRIG_OS_MACOS)
+#   include <sys/sysctl.h>
 #endif
 
 
@@ -62,13 +64,16 @@ xmrig::BasicCpuInfo::BasicCpuInfo() :
 #   endif
 #   endif
 
-#   ifdef XMRIG_OS_UNIX
+#   if defined(XMRIG_OS_UNIX)
     auto name = cpu_name_arm();
     if (!name.isNull()) {
         strncpy(m_brand, name, sizeof(m_brand) - 1);
     }
 
     m_flags.set(FLAG_PDPE1GB, std::ifstream("/sys/kernel/mm/hugepages/hugepages-1048576kB/nr_hugepages").good());
+#   elif defined(XMRIG_OS_MACOS)
+    size_t buflen = sizeof(m_brand);
+    sysctlbyname("machdep.cpu.brand_string", &m_brand, &buflen, nullptr, 0);
 #   endif
 }
 

src/crypto/cn/CnHash.cpp

@@ -219,7 +219,7 @@ static void patchAsmVariants()
         patchCode(cn_double_double_mainloop_sandybridge_asm, cnv2_double_mainloop_sandybridge_asm,  ITER);
     }
 
-    VirtualMemory::protectExecutableMemory(base, allocation_size);
+    VirtualMemory::protectRX(base, allocation_size);
     VirtualMemory::flushInstructionCache(base, allocation_size);
 }
 } // namespace xmrig

src/crypto/common/VirtualMemory.cpp

@@ -1,14 +1,7 @@
 /* XMRig
- * Copyright 2010      Jeff Garzik <jgarzik@pobox.com>
+ * Copyright (c) 2018-2020 tevador     <tevador@gmail.com>
- * Copyright 2012-2014 pooler      <pooler@litecoinpool.org>
+ * Copyright (c) 2018-2020 SChernykh   <https://github.com/SChernykh>
- * Copyright 2014      Lucas Jones <https://github.com/lucasjones>
+ * Copyright (c) 2016-2020 XMRig       <https://github.com/xmrig>, <support@xmrig.com>
- * Copyright 2014-2016 Wolf9466    <https://github.com/OhGodAPet>
- * Copyright 2016      Jay D Dee   <jayddee246@gmail.com>
- * Copyright 2017-2018 XMR-Stak    <https://github.com/fireice-uk>, <https://github.com/psychocrypt>
- * Copyright 2018      Lee Clagett <https://github.com/vtnerd>
- * Copyright 2018-2019 tevador     <tevador@gmail.com>
- * Copyright 2018-2020 SChernykh   <https://github.com/SChernykh>
- * Copyright 2016-2020 XMRig       <https://github.com/xmrig>, <support@xmrig.com>
  *
  *   This program is free software: you can redistribute it and/or modify
  *   it under the terms of the GNU General Public License as published by

src/crypto/common/VirtualMemory.h

@@ -1,14 +1,7 @@
 /* XMRig
- * Copyright 2010      Jeff Garzik <jgarzik@pobox.com>
+ * Copyright (c) 2018-2020 tevador     <tevador@gmail.com>
- * Copyright 2012-2014 pooler      <pooler@litecoinpool.org>
+ * Copyright (c) 2018-2020 SChernykh   <https://github.com/SChernykh>
- * Copyright 2014      Lucas Jones <https://github.com/lucasjones>
+ * Copyright (c) 2016-2020 XMRig       <https://github.com/xmrig>, <support@xmrig.com>
- * Copyright 2014-2016 Wolf9466    <https://github.com/OhGodAPet>
- * Copyright 2016      Jay D Dee   <jayddee246@gmail.com>
- * Copyright 2017-2018 XMR-Stak    <https://github.com/fireice-uk>, <https://github.com/psychocrypt>
- * Copyright 2018      Lee Clagett <https://github.com/vtnerd>
- * Copyright 2018-2019 tevador     <tevador@gmail.com>
- * Copyright 2018-2020 SChernykh   <https://github.com/SChernykh>
- * Copyright 2016-2020 XMRig       <https://github.com/xmrig>, <support@xmrig.com>
  *
  *   This program is free software: you can redistribute it and/or modify
  *   it under the terms of the GNU General Public License as published by
@@ -60,6 +53,9 @@ public:
 
     static bool isHugepagesAvailable();
     static bool isOneGbPagesAvailable();
+    static bool protectRW(void *p, size_t size);
+    static bool protectRWX(void *p, size_t size);
+    static bool protectRX(void *p, size_t size);
     static uint32_t bindToNUMANode(int64_t affinity);
     static void *allocateExecutableMemory(size_t size, bool hugePages);
     static void *allocateLargePagesMemory(size_t size);
@@ -68,8 +64,6 @@ public:
     static void flushInstructionCache(void *p, size_t size);
     static void freeLargePagesMemory(void *p, size_t size);
     static void init(size_t poolSize, bool hugePages);
-    static void protectExecutableMemory(void *p, size_t size);
-    static void unprotectExecutableMemory(void *p, size_t size);
 
     static inline constexpr size_t align(size_t pos, size_t align = 2097152) { return ((pos - 1) / align + 1) * align; }
 

src/crypto/common/VirtualMemory_unix.cpp

@@ -1,14 +1,7 @@
 /* XMRig
- * Copyright 2010      Jeff Garzik <jgarzik@pobox.com>
+ * Copyright (c) 2018-2020 tevador     <tevador@gmail.com>
- * Copyright 2012-2014 pooler      <pooler@litecoinpool.org>
+ * Copyright (c) 2018-2020 SChernykh   <https://github.com/SChernykh>
- * Copyright 2014      Lucas Jones <https://github.com/lucasjones>
+ * Copyright (c) 2016-2020 XMRig       <https://github.com/xmrig>, <support@xmrig.com>
- * Copyright 2014-2016 Wolf9466    <https://github.com/OhGodAPet>
- * Copyright 2016      Jay D Dee   <jayddee246@gmail.com>
- * Copyright 2017-2018 XMR-Stak    <https://github.com/fireice-uk>, <https://github.com/psychocrypt>
- * Copyright 2018      Lee Clagett <https://github.com/vtnerd>
- * Copyright 2018-2019 SChernykh   <https://github.com/SChernykh>
- * Copyright 2018-2019 tevador     <tevador@gmail.com>
- * Copyright 2016-2019 XMRig       <https://github.com/xmrig>, <support@xmrig.com>
  *
  *   This program is free software: you can redistribute it and/or modify
  *   it under the terms of the GNU General Public License as published by
@@ -34,8 +27,16 @@
 #include "crypto/common/VirtualMemory.h"
 
 
-#if defined(__APPLE__)
+#ifdef __APPLE__
+#   include <TargetConditionals.h>
 #   include <mach/vm_statistics.h>
+#   ifdef XMRIG_OS_MACOS
+#       define MEXTRA MAP_JIT
+#   else
+#       define MEXTRA 0
+#   endif
+#else
+#   define MEXTRA 0
 #endif
 
 
@@ -47,6 +48,13 @@
 #endif
 
 
+#ifdef XMRIG_SECURE_JIT
+#   define SECURE_PROT_EXEC 0
+#else
+#   define SECURE_PROT_EXEC PROT_EXEC
+#endif
+
+
 bool xmrig::VirtualMemory::isHugepagesAvailable()
 {
     return true;
@@ -63,19 +71,37 @@ bool xmrig::VirtualMemory::isOneGbPagesAvailable()
 }
 
 
+bool xmrig::VirtualMemory::protectRW(void *p, size_t size)
+{
+    return mprotect(p, size, PROT_READ | PROT_WRITE) == 0;
+}
+
+
+bool xmrig::VirtualMemory::protectRWX(void *p, size_t size)
+{
+    return mprotect(p, size, PROT_READ | PROT_WRITE | PROT_EXEC) == 0;
+}
+
+
+bool xmrig::VirtualMemory::protectRX(void *p, size_t size)
+{
+    return mprotect(p, size, PROT_READ | PROT_EXEC) == 0;
+}
+
+
 void *xmrig::VirtualMemory::allocateExecutableMemory(size_t size, bool hugePages)
 {
 #   if defined(__APPLE__)
-    void *mem = mmap(0, size, PROT_READ | PROT_WRITE | PROT_EXEC, MAP_PRIVATE | MAP_ANON, -1, 0);
+    void *mem = mmap(0, size, PROT_READ | PROT_WRITE | SECURE_PROT_EXEC, MAP_PRIVATE | MAP_ANON | MEXTRA, -1, 0);
 #   elif defined(__FreeBSD__)
     void *mem = nullptr;
 
     if (hugePages) {
-        mem = mmap(0, size, PROT_READ | PROT_WRITE | PROT_EXEC, MAP_PRIVATE | MAP_ANONYMOUS | MAP_ALIGNED_SUPER | MAP_PREFAULT_READ, -1, 0);
+        mem = mmap(0, size, PROT_READ | PROT_WRITE | SECURE_PROT_EXEC, MAP_PRIVATE | MAP_ANONYMOUS | MAP_ALIGNED_SUPER | MAP_PREFAULT_READ, -1, 0);
     }
 
     if (!mem) {
-        mem = mmap(0, size, PROT_READ | PROT_WRITE | PROT_EXEC, MAP_PRIVATE | MAP_ANONYMOUS, -1, 0);
+        mem = mmap(0, size, PROT_READ | PROT_WRITE | SECURE_PROT_EXEC, MAP_PRIVATE | MAP_ANONYMOUS, -1, 0);
     }
 
 #   else
@@ -91,11 +117,11 @@ void *xmrig::VirtualMemory::allocateExecutableMemory(size_t size, bool hugePages
     void *mem = nullptr;
 
     if (hugePages) {
-        mem = mmap(0, align(size), PROT_READ | PROT_WRITE | PROT_EXEC, MAP_PRIVATE | MAP_ANONYMOUS | MAP_POPULATE | flag_2mb, -1, 0);
+        mem = mmap(0, align(size), PROT_READ | PROT_WRITE | SECURE_PROT_EXEC, MAP_PRIVATE | MAP_ANONYMOUS | MAP_POPULATE | flag_2mb, -1, 0);
     }
 
     if (!mem) {
-        mem = mmap(0, size, PROT_READ | PROT_WRITE | PROT_EXEC, MAP_PRIVATE | MAP_ANONYMOUS, -1, 0);
+        mem = mmap(0, size, PROT_READ | PROT_WRITE | SECURE_PROT_EXEC, MAP_PRIVATE | MAP_ANONYMOUS, -1, 0);
     }
 
 #   endif
@@ -164,18 +190,6 @@ void xmrig::VirtualMemory::freeLargePagesMemory(void *p, size_t size)
 }
 
 
-void xmrig::VirtualMemory::protectExecutableMemory(void *p, size_t size)
-{
-    mprotect(p, size, PROT_READ | PROT_EXEC);
-}
-
-
-void xmrig::VirtualMemory::unprotectExecutableMemory(void *p, size_t size)
-{
-    mprotect(p, size, PROT_WRITE | PROT_EXEC);
-}
-
-
 void xmrig::VirtualMemory::osInit(bool)
 {
 }

src/crypto/common/VirtualMemory_win.cpp

@@ -1,14 +1,7 @@
 /* XMRig
- * Copyright 2010      Jeff Garzik <jgarzik@pobox.com>
+ * Copyright (c) 2018-2020 tevador     <tevador@gmail.com>
- * Copyright 2012-2014 pooler      <pooler@litecoinpool.org>
+ * Copyright (c) 2018-2020 SChernykh   <https://github.com/SChernykh>
- * Copyright 2014      Lucas Jones <https://github.com/lucasjones>
+ * Copyright (c) 2016-2020 XMRig       <https://github.com/xmrig>, <support@xmrig.com>
- * Copyright 2014-2016 Wolf9466    <https://github.com/OhGodAPet>
- * Copyright 2016      Jay D Dee   <jayddee246@gmail.com>
- * Copyright 2017-2018 XMR-Stak    <https://github.com/fireice-uk>, <https://github.com/psychocrypt>
- * Copyright 2018      Lee Clagett <https://github.com/vtnerd>
- * Copyright 2018-2019 SChernykh   <https://github.com/SChernykh>
- * Copyright 2018-2019 tevador     <tevador@gmail.com>
- * Copyright 2016-2019 XMRig       <https://github.com/xmrig>, <support@xmrig.com>
  *
  *   This program is free software: you can redistribute it and/or modify
  *   it under the terms of the GNU General Public License as published by
@@ -36,6 +29,13 @@
 #include "crypto/common/VirtualMemory.h"
 
 
+#ifdef XMRIG_SECURE_JIT
+#   define SECURE_PAGE_EXECUTE_READWRITE PAGE_READWRITE
+#else
+#   define SECURE_PAGE_EXECUTE_READWRITE PAGE_EXECUTE_READWRITE
+#endif
+
+
 namespace xmrig {
 
 
@@ -162,16 +162,40 @@ bool xmrig::VirtualMemory::isOneGbPagesAvailable()
 }
 
 
+bool xmrig::VirtualMemory::protectRW(void *p, size_t size)
+{
+    DWORD oldProtect;
+
+    return VirtualProtect(p, size, PAGE_READWRITE, &oldProtect) != 0;
+}
+
+
+bool xmrig::VirtualMemory::protectRWX(void *p, size_t size)
+{
+    DWORD oldProtect;
+
+    return VirtualProtect(p, size, PAGE_EXECUTE_READWRITE, &oldProtect) != 0;
+}
+
+
+bool xmrig::VirtualMemory::protectRX(void *p, size_t size)
+{
+    DWORD oldProtect;
+
+    return VirtualProtect(p, size, PAGE_EXECUTE_READ, &oldProtect) != 0;
+}
+
+
 void *xmrig::VirtualMemory::allocateExecutableMemory(size_t size, bool hugePages)
 {
     void* result = nullptr;
 
     if (hugePages) {
-        result = VirtualAlloc(nullptr, align(size), MEM_COMMIT | MEM_RESERVE | MEM_LARGE_PAGES, PAGE_EXECUTE_READWRITE);
+        result = VirtualAlloc(nullptr, align(size), MEM_COMMIT | MEM_RESERVE | MEM_LARGE_PAGES, SECURE_PAGE_EXECUTE_READWRITE);
     }
 
     if (!result) {
-        result = VirtualAlloc(nullptr, size, MEM_COMMIT | MEM_RESERVE, PAGE_EXECUTE_READWRITE);
+        result = VirtualAlloc(nullptr, size, MEM_COMMIT | MEM_RESERVE, SECURE_PAGE_EXECUTE_READWRITE);
     }
 
     return result;
@@ -209,20 +233,6 @@ void xmrig::VirtualMemory::freeLargePagesMemory(void *p, size_t)
 }
 
 
-void xmrig::VirtualMemory::protectExecutableMemory(void *p, size_t size)
-{
-    DWORD oldProtect;
-    VirtualProtect(p, size, PAGE_EXECUTE_READ, &oldProtect);
-}
-
-
-void xmrig::VirtualMemory::unprotectExecutableMemory(void *p, size_t size)
-{
-    DWORD oldProtect;
-    VirtualProtect(p, size, PAGE_EXECUTE_READWRITE, &oldProtect);
-}
-
-
 void xmrig::VirtualMemory::osInit(bool hugePages)
 {
     if (hugePages) {

src/crypto/randomx/dataset.cpp

@@ -1,5 +1,7 @@
 /*
-Copyright (c) 2018-2019, tevador <tevador@gmail.com>
+Copyright (c) 2018-2020, tevador    <tevador@gmail.com>
+Copyright (c) 2019-2020, SChernykh  <https://github.com/SChernykh>
+Copyright (c) 2019-2020, XMRig      <https://github.com/xmrig>, <support@xmrig.com>
 
 All rights reserved.
 
@@ -77,16 +79,16 @@ namespace randomx {
 		context.pwdlen = (uint32_t)keySize;
 		context.salt = CONST_CAST(uint8_t *)RandomX_CurrentConfig.ArgonSalt;
 		context.saltlen = (uint32_t)strlen(RandomX_CurrentConfig.ArgonSalt);
-		context.secret = NULL;
+		context.secret = nullptr;
 		context.secretlen = 0;
-		context.ad = NULL;
+		context.ad = nullptr;
 		context.adlen = 0;
 		context.t_cost = RandomX_CurrentConfig.ArgonIterations;
 		context.m_cost = RandomX_CurrentConfig.ArgonMemory;
 		context.lanes = RandomX_CurrentConfig.ArgonLanes;
 		context.threads = 1;
-		context.allocate_cbk = NULL;
+		context.allocate_cbk = nullptr;
-		context.free_cbk = NULL;
+		context.free_cbk = nullptr;
 		context.flags = ARGON2_DEFAULT_FLAGS;
 		context.version = ARGON2_VERSION_NUMBER;
 
@@ -100,8 +102,17 @@ namespace randomx {
 
 	void initCacheCompile(randomx_cache* cache, const void* key, size_t keySize) {
 		initCache(cache, key, keySize);
+
+#		ifdef XMRIG_SECURE_JIT
+		cache->jit->enableWriting();
+#		endif
+
 		cache->jit->generateSuperscalarHash(cache->programs);
 		cache->jit->generateDatasetInitCode();
+
+#		ifdef XMRIG_SECURE_JIT
+		cache->jit->enableExecution();
+#		endif
 	}
 
 	constexpr uint64_t superscalarMul0 = 6364136223846793005ULL;

src/crypto/randomx/jit_compiler_a64.cpp

@@ -1,6 +1,7 @@
 /*
-Copyright (c) 2018-2019, tevador <tevador@gmail.com>
+Copyright (c) 2018-2020, tevador    <tevador@gmail.com>
-Copyright (c) 2019, SChernykh    <https://github.com/SChernykh>
+Copyright (c) 2019-2020, SChernykh  <https://github.com/SChernykh>
+Copyright (c) 2019-2020, XMRig      <https://github.com/xmrig>, <support@xmrig.com>
 
 All rights reserved.
 
@@ -28,9 +29,10 @@ OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 */
 
 #include "crypto/randomx/jit_compiler_a64.hpp"
-#include "crypto/randomx/superscalar.hpp"
+#include "crypto/common/VirtualMemory.h"
 #include "crypto/randomx/program.hpp"
 #include "crypto/randomx/reciprocal.h"
+#include "crypto/randomx/superscalar.hpp"
 #include "crypto/randomx/virtual_memory.hpp"
 
 static bool hugePagesJIT = false;
@@ -357,6 +359,21 @@ size_t JitCompilerA64::getCodeSize()
 	return CodeSize;
 }
 
+void JitCompilerA64::enableWriting()
+{
+	xmrig::VirtualMemory::protectRW(code, CodeSize + CalcDatasetItemSize());
+}
+
+void JitCompilerA64::enableExecution()
+{
+	xmrig::VirtualMemory::protectRX(code, CodeSize + CalcDatasetItemSize());
+}
+
+void JitCompilerA64::enableAll()
+{
+	xmrig::VirtualMemory::protectRWX(code, CodeSize + CalcDatasetItemSize());
+}
+
 void JitCompilerA64::emitMovImmediate(uint32_t dst, uint32_t imm, uint8_t* code, uint32_t& codePos)
 {
 	uint32_t k = codePos;

src/crypto/randomx/jit_compiler_a64.hpp

@@ -1,6 +1,7 @@
 /*
-Copyright (c) 2018-2019, tevador <tevador@gmail.com>
+Copyright (c) 2018-2020, tevador    <tevador@gmail.com>
-Copyright (c) 2019, SChernykh    <https://github.com/SChernykh>
+Copyright (c) 2019-2020, SChernykh  <https://github.com/SChernykh>
+Copyright (c) 2019-2020, XMRig      <https://github.com/xmrig>, <support@xmrig.com>
 
 All rights reserved.
 
@@ -63,6 +64,10 @@ namespace randomx {
 		uint8_t* getCode() { return code; }
 		size_t getCodeSize();
 
+		void enableWriting();
+		void enableExecution();
+		void enableAll();
+
 		static InstructionGeneratorA64 engine[256];
 		uint32_t reg_changed_offset[8];
 		uint8_t* code;

src/crypto/randomx/jit_compiler_fallback.hpp

@@ -1,5 +1,7 @@
 /*
-Copyright (c) 2018-2019, tevador <tevador@gmail.com>
+Copyright (c) 2018-2020, tevador    <tevador@gmail.com>
+Copyright (c) 2019-2020, SChernykh  <https://github.com/SChernykh>
+Copyright (c) 2019-2020, XMRig      <https://github.com/xmrig>, <support@xmrig.com>
 
 All rights reserved.
 
@@ -70,5 +72,8 @@ namespace randomx {
 		size_t getCodeSize() {
 			return 0;
 		}
+		void enableWriting() {}
+		void enableExecution() {}
+		void enableAll() {}
 	};
 }

src/crypto/randomx/jit_compiler_x86.cpp

@@ -1,5 +1,7 @@
 /*
-Copyright (c) 2018-2019, tevador <tevador@gmail.com>
+Copyright (c) 2018-2020, tevador    <tevador@gmail.com>
+Copyright (c) 2019-2020, SChernykh  <https://github.com/SChernykh>
+Copyright (c) 2019-2020, XMRig      <https://github.com/xmrig>, <support@xmrig.com>
 
 All rights reserved.
 
@@ -30,8 +32,10 @@ OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 #include <cstring>
 #include <climits>
 #include <atomic>
+
 #include "crypto/randomx/jit_compiler_x86.hpp"
 #include "backend/cpu/Cpu.h"
+#include "crypto/common/VirtualMemory.h"
 #include "crypto/randomx/jit_compiler_x86_static.hpp"
 #include "crypto/randomx/program.hpp"
 #include "crypto/randomx/reciprocal.h"
@@ -170,6 +174,18 @@ namespace randomx {
 		return codePos < prologueSize ? 0 : codePos - prologueSize;
 	}
 
+	void JitCompilerX86::enableAll() {
+		xmrig::VirtualMemory::protectRWX(code, CodeSize);
+	}
+
+	void JitCompilerX86::enableWriting() {
+		xmrig::VirtualMemory::protectRW(code, CodeSize);
+	}
+
+	void JitCompilerX86::enableExecution() {
+		xmrig::VirtualMemory::protectRX(code, CodeSize);
+	}
+
 	static inline void cpuid(uint32_t level, int32_t output[4])
 	{
 		memset(output, 0, sizeof(int32_t) * 4);

src/crypto/randomx/jit_compiler_x86.hpp

@@ -1,5 +1,7 @@
 /*
-Copyright (c) 2018-2019, tevador <tevador@gmail.com>
+Copyright (c) 2018-2020, tevador    <tevador@gmail.com>
+Copyright (c) 2019-2020, SChernykh  <https://github.com/SChernykh>
+Copyright (c) 2019-2020, XMRig      <https://github.com/xmrig>, <support@xmrig.com>
 
 All rights reserved.
 
@@ -65,6 +67,9 @@ namespace randomx {
 			return code;
 		}
 		size_t getCodeSize();
+		void enableWriting();
+		void enableExecution();
+		void enableAll();
 
 		alignas(64) static InstructionGeneratorX86 engine[256];
 

src/crypto/randomx/vm_compiled.cpp

@@ -1,5 +1,7 @@
 /*
-Copyright (c) 2018-2019, tevador <tevador@gmail.com>
+Copyright (c) 2018-2020, tevador    <tevador@gmail.com>
+Copyright (c) 2019-2020, SChernykh  <https://github.com/SChernykh>
+Copyright (c) 2019-2020, XMRig      <https://github.com/xmrig>, <support@xmrig.com>
 
 All rights reserved.
 
@@ -47,7 +49,17 @@ namespace randomx {
 		compiler.prepare();
 		VmBase<softAes>::generateProgram(seed);
 		randomx_vm::initialize();
+
+#		ifdef XMRIG_SECURE_JIT
+		compiler.enableWriting();
+#		endif
+
 		compiler.generateProgram(program, config, randomx_vm::getFlags());
+
+#		ifdef XMRIG_SECURE_JIT
+		compiler.enableExecution();
+#		endif
+
 		mem.memory = datasetPtr->memory + datasetOffset;
 		execute();
 	}

src/crypto/randomx/vm_compiled_light.cpp

@@ -1,5 +1,7 @@
 /*
-Copyright (c) 2018-2019, tevador <tevador@gmail.com>
+Copyright (c) 2018-2020, tevador    <tevador@gmail.com>
+Copyright (c) 2019-2020, SChernykh  <https://github.com/SChernykh>
+Copyright (c) 2019-2020, XMRig      <https://github.com/xmrig>, <support@xmrig.com>
 
 All rights reserved.
 
@@ -36,14 +38,33 @@ namespace randomx {
 	void CompiledLightVm<softAes>::setCache(randomx_cache* cache) {
 		cachePtr = cache;
 		mem.memory = cache->memory;
+
+#		ifdef XMRIG_SECURE_JIT
+		compiler.enableWriting();
+#		endif
+
 		compiler.generateSuperscalarHash(cache->programs);
+
+#		ifdef XMRIG_SECURE_JIT
+		compiler.enableExecution();
+#		endif
 	}
 
 	template<int softAes>
 	void CompiledLightVm<softAes>::run(void* seed) {
 		VmBase<softAes>::generateProgram(seed);
 		randomx_vm::initialize();
+
+#		ifdef XMRIG_SECURE_JIT
+		compiler.enableWriting();
+#		endif
+
 		compiler.generateProgramLight(program, config, datasetOffset);
+
+#		ifdef XMRIG_SECURE_JIT
+		compiler.enableExecution();
+#		endif
+
 		CompiledVm<softAes>::execute();
 	}