Don't use exceptions in low-level mem allocator

CMakeLists.txt

@@ -39,7 +39,7 @@ src/bytecode_machine.cpp
 src/cpu.cpp
 src/dataset.cpp
 src/soft_aes.cpp
-src/virtual_memory.cpp
+src/virtual_memory.c
 src/vm_interpreted.cpp
 src/allocator.cpp
 src/assembly_generator_x86.cpp

src/allocator.cpp

@@ -29,7 +29,7 @@ OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 #include <new>
 #include "allocator.hpp"
 #include "intrin_portable.h"
-#include "virtual_memory.hpp"
+#include "virtual_memory.h"
 #include "common.hpp"
 
 namespace randomx {
@@ -50,11 +50,14 @@ namespace randomx {
 	template struct AlignedAllocator<CacheLineSize>;
 
 	void* LargePageAllocator::allocMemory(size_t count) {
-		return allocLargePagesMemory(count);
+		void *mem = allocLargePagesMemory(count);
+		if (mem == nullptr)
+			throw std::bad_alloc();
+		return mem;
 	}
 
 	void LargePageAllocator::freeMemory(void* ptr, size_t count) {
 		freePagedMemory(ptr, count);
 	};
 
-}
+}

src/dataset.cpp

@@ -42,7 +42,7 @@ OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 
 #include "common.hpp"
 #include "dataset.hpp"
-#include "virtual_memory.hpp"
+#include "virtual_memory.h"
 #include "superscalar.hpp"
 #include "blake2_generator.hpp"
 #include "reciprocal.h"

src/jit_compiler_a64.cpp

@@ -31,7 +31,7 @@ OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 #include "superscalar.hpp"
 #include "program.hpp"
 #include "reciprocal.h"
-#include "virtual_memory.hpp"
+#include "virtual_memory.h"
 
 namespace ARMV8A {
 
@@ -93,6 +93,8 @@ JitCompilerA64::JitCompilerA64()
 	, literalPos(ImulRcpLiteralsEnd)
 	, num32bitLiterals(0)
 {
+	if (code == nullptr)
+		throw std::runtime_error("allocMemoryPages");
 	memset(reg_changed_offset, 0, sizeof(reg_changed_offset));
 	memcpy(code, (void*) randomx_program_aarch64, CodeSize);
 

src/jit_compiler_x86.cpp

@@ -34,7 +34,7 @@ OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 #include "superscalar.hpp"
 #include "program.hpp"
 #include "reciprocal.h"
-#include "virtual_memory.hpp"
+#include "virtual_memory.h"
 
 namespace randomx {
 	/*
@@ -225,6 +225,8 @@ namespace randomx {
 
 	JitCompilerX86::JitCompilerX86() {
 		code = (uint8_t*)allocMemoryPages(CodeSize);
+		if (code == nullptr)
+			throw std::runtime_error("allocMemoryPages");
 		memcpy(code, codePrologue, prologueSize);
 		memcpy(code + epilogueOffset, codeEpilogue, epilogueSize);
 	}

src/randomx.cpp

@@ -113,6 +113,10 @@ extern "C" {
 				cache = nullptr;
 			}
 		}
+		if (cache && cache->memory == nullptr) {
+			randomx_release_cache(cache);
+			cache = nullptr;
+		}
 
 		return cache;
 	}
@@ -162,6 +166,10 @@ extern "C" {
 				dataset = nullptr;
 			}
 		}
+		if (dataset && dataset->memory == nullptr) {
+			randomx_release_dataset(dataset);
+			dataset = nullptr;
+		}
 
 		return dataset;
 	}

src/virtual_memory.c

@@ -26,9 +26,7 @@ OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
 OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 */
 
-#include "virtual_memory.hpp"
+#include "virtual_memory.h"
-
-#include <stdexcept>
 
 #if defined(_WIN32) || defined(__CYGWIN__)
 #include <windows.h>
@@ -40,10 +38,12 @@ OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 # if TARGET_OS_OSX
 #  define USE_PTHREAD_JIT_WP	1
 #  include <pthread.h>
+#  include <sys/utsname.h>
 # endif
 #endif
 #include <sys/types.h>
 #include <sys/mman.h>
+#include <errno.h>
 #ifndef MAP_ANONYMOUS
 #define MAP_ANONYMOUS MAP_ANON
 #endif
@@ -53,27 +53,48 @@ OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 #define PAGE_EXECUTE_READWRITE (PROT_READ | PROT_WRITE | PROT_EXEC)
 #endif
 
-#if defined(_WIN32) || defined(__CYGWIN__)
+#if defined(USE_PTHREAD_JIT_WP) && defined(MAC_OS_VERSION_11_0) \
-std::string getErrorMessage(const char* function) {
+	&& MAC_OS_X_VERSION_MAX_ALLOWED >= MAC_OS_VERSION_11_0
-	LPSTR messageBuffer = nullptr;
+static int MacOSchecked, MacOSver;
-	size_t size = FormatMessageA(FORMAT_MESSAGE_ALLOCATE_BUFFER | FORMAT_MESSAGE_FROM_SYSTEM | FORMAT_MESSAGE_IGNORE_INSERTS,
+/* This function is used implicitly by clang's __builtin_available() checker.
-		NULL, GetLastError(), MAKELANGID(LANG_NEUTRAL, SUBLANG_DEFAULT), (LPSTR)&messageBuffer, 0, NULL);
+ * When cross-compiling, the library containing this function doesn't exist,
-	std::string message(messageBuffer, size);
+ * and linking will fail because the symbol is unresolved. The function here
-	LocalFree(messageBuffer);
+ * is a quick and dirty hack to get close enough to identify MacOSX 11.0.
-	return std::string(function) + std::string(": ") + message;
+ */
+static int32_t __isOSVersionAtLeast(int32_t major, int32_t minor, int32_t subminor) {
+	if (!MacOSchecked) {
+	    struct utsname ut;
+		int mmaj, mmin;
+		uname(&ut);
+		sscanf(ut.release, "%d.%d", &mmaj, &mmin);
+		// The utsname release version is 9 greater than the canonical OS version
+		mmaj -= 9;
+		MacOSver = (mmaj << 8) | mmin;
+		MacOSchecked = 1;
+	}
+	return MacOSver >= ((major << 8) | minor);
 }
+#endif
 
-void setPrivilege(const char* pszPrivilege, BOOL bEnable) {
+
+#if defined(_WIN32) || defined(__CYGWIN__)
+#define Fail(func)	do  {*errfunc = func; return GetLastError();} while(0)
+int setPrivilege(const char* pszPrivilege, BOOL bEnable, char **errfunc) {
 	HANDLE           hToken;
 	TOKEN_PRIVILEGES tp;
 	BOOL             status;
-	DWORD            error;
+	DWORD            error = 0;
+
+	*errfunc = NULL;
 
 	if (!OpenProcessToken(GetCurrentProcess(), TOKEN_ADJUST_PRIVILEGES | TOKEN_QUERY, &hToken))
-		throw std::runtime_error(getErrorMessage("OpenProcessToken"));
+		Fail("OpenProcessToken");
 
-	if (!LookupPrivilegeValue(NULL, pszPrivilege, &tp.Privileges[0].Luid))
+	if (!LookupPrivilegeValue(NULL, pszPrivilege, &tp.Privileges[0].Luid)) {
-		throw std::runtime_error(getErrorMessage("LookupPrivilegeValue"));
+		*errfunc = "LookupPrivilegeValue";
+		error = GetLastError();
+		goto out;
+	}
 
 	tp.PrivilegeCount = 1;
 
@@ -85,20 +106,28 @@ void setPrivilege(const char* pszPrivilege, BOOL bEnable) {
 	status = AdjustTokenPrivileges(hToken, FALSE, &tp, 0, (PTOKEN_PRIVILEGES)NULL, 0);
 
 	error = GetLastError();
-	if (!status || (error != ERROR_SUCCESS))
+	if (!status || (error != ERROR_SUCCESS)) {
-		throw std::runtime_error(getErrorMessage("AdjustTokenPrivileges"));
+		*errfunc = "AdjustTokenPrivileges";
+		goto out;
+	}
 
-	if (!CloseHandle(hToken))
+out:
-		throw std::runtime_error(getErrorMessage("CloseHandle"));
+	if (!CloseHandle(hToken)) {
+		if (*errfunc == NULL) {
+			*errfunc = "CloseHandle";
+			error = GetLastError();
+		}
+	}
+	return error;
 }
+#else
+#define Fail(func)	do  {*errfunc = func; return errno;} while(0)
 #endif
 
-void* allocMemoryPages(std::size_t bytes) {
+void* allocMemoryPages(size_t bytes) {
 	void* mem;
 #if defined(_WIN32) || defined(__CYGWIN__)
-	mem = VirtualAlloc(nullptr, bytes, MEM_COMMIT, PAGE_READWRITE);
+	mem = VirtualAlloc(NULL, bytes, MEM_COMMIT, PAGE_READWRITE);
-	if (mem == nullptr)
-		throw std::runtime_error(getErrorMessage("allocMemoryPages - VirtualAlloc"));
 #else
 	#if defined(__NetBSD__)
 		#define RESERVED_FLAGS PROT_MPROTECT(PROT_EXEC)
@@ -112,9 +141,7 @@ void* allocMemoryPages(std::size_t bytes) {
 		#define MEXTRA 0
 		#define PEXTRA	0
 	#endif
-	mem = mmap(nullptr, bytes, PAGE_READWRITE | RESERVED_FLAGS | PEXTRA, MAP_ANONYMOUS | MAP_PRIVATE | MEXTRA, -1, 0);
+	mem = mmap(NULL, bytes, PAGE_READWRITE | RESERVED_FLAGS | PEXTRA, MAP_ANONYMOUS | MAP_PRIVATE | MEXTRA, -1, 0);
-	if (mem == MAP_FAILED)
-		throw std::runtime_error("allocMemoryPages - mmap failed");
 #if defined(USE_PTHREAD_JIT_WP) && defined(MAC_OS_VERSION_11_0) \
 	&& MAC_OS_X_VERSION_MAX_ALLOWED >= MAC_OS_VERSION_11_0
 	if (__builtin_available(macOS 11.0, *)) {
@@ -125,76 +152,81 @@ void* allocMemoryPages(std::size_t bytes) {
 	return mem;
 }
 
-static inline void pageProtect(void* ptr, std::size_t bytes, int rules) {
+static inline int pageProtect(void* ptr, size_t bytes, int rules, char **errfunc) {
 #if defined(_WIN32) || defined(__CYGWIN__)
 	DWORD oldp;
 	if (!VirtualProtect(ptr, bytes, (DWORD)rules, &oldp)) {
-		throw std::runtime_error(getErrorMessage("VirtualProtect"));
+		Fail("VirtualProtect");
 	}
 #else
 	if (-1 == mprotect(ptr, bytes, rules))
-		throw std::runtime_error("mprotect failed");
+		Fail("mprotect");
 #endif
+	return 0;
 }
 
-void setPagesRW(void* ptr, std::size_t bytes) {
+void setPagesRW(void* ptr, size_t bytes) {
+	char *errfunc;
 #if defined(USE_PTHREAD_JIT_WP) && defined(MAC_OS_VERSION_11_0) \
 	&& MAC_OS_X_VERSION_MAX_ALLOWED >= MAC_OS_VERSION_11_0
 	if (__builtin_available(macOS 11.0, *)) {
 		pthread_jit_write_protect_np(false);
 	} else {
-		pageProtect(ptr, bytes, PAGE_READWRITE);
+		pageProtect(ptr, bytes, PAGE_READWRITE, &errfunc);
 	}
 #else
-	pageProtect(ptr, bytes, PAGE_READWRITE);
+	pageProtect(ptr, bytes, PAGE_READWRITE, &errfunc);
 #endif
 }
 
-void setPagesRX(void* ptr, std::size_t bytes) {
+void setPagesRX(void* ptr, size_t bytes) {
+	char *errfunc;
 #if defined(USE_PTHREAD_JIT_WP) && defined(MAC_OS_VERSION_11_0) \
 	&& MAC_OS_X_VERSION_MAX_ALLOWED >= MAC_OS_VERSION_11_0
 	if (__builtin_available(macOS 11.0, *)) {
 		pthread_jit_write_protect_np(true);
 	} else {
-		pageProtect(ptr, bytes, PAGE_EXECUTE_READ);
+		pageProtect(ptr, bytes, PAGE_EXECUTE_READ, &errfunc);
 	}
 #else
-	pageProtect(ptr, bytes, PAGE_EXECUTE_READ);
+	pageProtect(ptr, bytes, PAGE_EXECUTE_READ, &errfunc);
 #endif
 }
 
-void setPagesRWX(void* ptr, std::size_t bytes) {
+void setPagesRWX(void* ptr, size_t bytes) {
-	pageProtect(ptr, bytes, PAGE_EXECUTE_READWRITE);
+	char *errfunc;
+	pageProtect(ptr, bytes, PAGE_EXECUTE_READWRITE, &errfunc);
 }
 
-void* allocLargePagesMemory(std::size_t bytes) {
+void* allocLargePagesMemory(size_t bytes) {
 	void* mem;
+	char *errfunc;
 #if defined(_WIN32) || defined(__CYGWIN__)
-	setPrivilege("SeLockMemoryPrivilege", 1);
+	if (setPrivilege("SeLockMemoryPrivilege", 1, &errfunc))
+		return NULL;
 	auto pageMinimum = GetLargePageMinimum();
-	if (pageMinimum > 0)
+	if (pageMinimum <= 0) {
-		mem = VirtualAlloc(NULL, alignSize(bytes, pageMinimum), MEM_COMMIT | MEM_RESERVE | MEM_LARGE_PAGES, PAGE_READWRITE);
+		errfunc = "No large pages";
-	else
+		return NULL;
-		throw std::runtime_error("allocLargePagesMemory - Large pages are not supported");
+	}
-	if (mem == nullptr)
+	mem = VirtualAlloc(NULL, alignSize(bytes, pageMinimum), MEM_COMMIT | MEM_RESERVE | MEM_LARGE_PAGES, PAGE_READWRITE);
-		throw std::runtime_error(getErrorMessage("allocLargePagesMemory - VirtualAlloc"));
 #else
 #ifdef __APPLE__
-	mem = mmap(nullptr, bytes, PROT_READ | PROT_WRITE, MAP_PRIVATE | MAP_ANONYMOUS, VM_FLAGS_SUPERPAGE_SIZE_2MB, 0);
+	mem = mmap(NULL, bytes, PROT_READ | PROT_WRITE, MAP_PRIVATE | MAP_ANONYMOUS, VM_FLAGS_SUPERPAGE_SIZE_2MB, 0);
 #elif defined(__FreeBSD__)
-	mem = mmap(nullptr, bytes, PROT_READ | PROT_WRITE, MAP_PRIVATE | MAP_ANONYMOUS | MAP_ALIGNED_SUPER, -1, 0);
+	mem = mmap(NULL, bytes, PROT_READ | PROT_WRITE, MAP_PRIVATE | MAP_ANONYMOUS | MAP_ALIGNED_SUPER, -1, 0);
 #elif defined(__OpenBSD__) || defined(__NetBSD__)
 	mem = MAP_FAILED; // OpenBSD does not support huge pages
 #else
-	mem = mmap(nullptr, bytes, PROT_READ | PROT_WRITE, MAP_PRIVATE | MAP_ANONYMOUS | MAP_HUGETLB | MAP_POPULATE, -1, 0);
+	mem = mmap(NULL, bytes, PROT_READ | PROT_WRITE, MAP_PRIVATE | MAP_ANONYMOUS | MAP_HUGETLB | MAP_POPULATE, -1, 0);
 #endif
 	if (mem == MAP_FAILED)
-		throw std::runtime_error("allocLargePagesMemory - mmap failed");
+		mem = NULL;
 #endif
 	return mem;
 }
 
-void freePagedMemory(void* ptr, std::size_t bytes) {
+void freePagedMemory(void* ptr, size_t bytes) {
 #if defined(_WIN32) || defined(__CYGWIN__)
 	VirtualFree(ptr, 0, MEM_RELEASE);
 #else

src/virtual_memory.h

@@ -28,15 +28,21 @@ OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 
 #pragma once
 
-#include <cstddef>
+#ifdef __cplusplus
+extern "C" {
+#endif
 
-constexpr std::size_t alignSize(std::size_t pos, std::size_t align) {
+#include <stddef.h>
-	return ((pos - 1) / align + 1) * align;
+
+#define alignSize(pos, align) (((pos - 1) / align + 1) * align)
+
+void* allocMemoryPages(size_t);
+void setPagesRW(void*, size_t);
+void setPagesRX(void*, size_t);
+void setPagesRWX(void*, size_t);
+void* allocLargePagesMemory(size_t);
+void freePagedMemory(void*, size_t);
+
+#ifdef __cplusplus
 }
-
+#endif
-void* allocMemoryPages(std::size_t);
-void setPagesRW(void*, std::size_t);
-void setPagesRX(void*, std::size_t);
-void setPagesRWX(void*, std::size_t);
-void* allocLargePagesMemory(std::size_t);
-void freePagedMemory(void*, std::size_t);