Disable W^X in Rosetta emulated x64 containers on macOS

src/coreclr/minipal/CMakeLists.txt

@@ -1,4 +1,5 @@
 include_directories(.)
+include_directories(${CLR_SRC_NATIVE_DIR})
 if (CLR_CMAKE_HOST_UNIX)
     add_subdirectory(Unix)
 else (CLR_CMAKE_HOST_UNIX)

src/coreclr/minipal/Unix/doublemapping.cpp

@@ -20,24 +20,13 @@
 #define memfd_create(...) syscall(__NR_memfd_create, __VA_ARGS__)
 #endif // TARGET_LINUX && !MFD_CLOEXEC
 #include "minipal.h"
+#include "minipal/cpufeatures.h"
 
-#if defined(TARGET_OSX) && defined(TARGET_AMD64)
-#include <mach/mach.h>
-#include <sys/sysctl.h>
+#ifdef TARGET_OSX
 
-bool IsProcessTranslated()
-{
-   int ret = 0;
-   size_t size = sizeof(ret);
-   if (sysctlbyname("sysctl.proc_translated", &ret, &size, NULL, 0) == -1)
-   {
-      return false;
-   }
-   return ret == 1;
-}
-#endif // TARGET_OSX && TARGET_AMD64
+#include <mach/mach.h>
 
-#ifndef TARGET_OSX
+#else // TARGET_OSX
 
 #ifdef TARGET_64BIT
 static const off_t MaxDoubleMappedSize = 2048ULL*1024*1024*1024;
@@ -49,6 +38,12 @@ static const off_t MaxDoubleMappedSize = UINT_MAX;
 
 bool VMToOSInterface::CreateDoubleMemoryMapper(void** pHandle, size_t *pMaxExecutableCodeSize)
 {
+    if (minipal_detect_rosetta())
+    {
+        // Rosetta doesn't support double mapping correctly
+        return false;
+    }
+
 #ifndef TARGET_OSX
 
 #ifdef TARGET_FREEBSD
@@ -78,14 +73,6 @@ bool VMToOSInterface::CreateDoubleMemoryMapper(void** pHandle, size_t *pMaxExecu
     *pHandle = (void*)(size_t)fd;
 #else // !TARGET_OSX
 
-#ifdef TARGET_AMD64
-    if (IsProcessTranslated())
-    {
-        // Rosetta doesn't support double mapping correctly
-        return false;
-    }
-#endif // TARGET_AMD64
-
     *pMaxExecutableCodeSize = SIZE_MAX;
     *pHandle = NULL;
 #endif // !TARGET_OSX

src/coreclr/minipal/Windows/doublemapping.cpp

@@ -6,6 +6,7 @@
 #include <inttypes.h>
 #include <assert.h>
 #include "minipal.h"
+#include "minipal/cpufeatures.h"
 
 #define HIDWORD(_qw)    ((ULONG)((_qw) >> 32))
 #define LODWORD(_qw)    ((ULONG)(_qw))
@@ -60,6 +61,12 @@ inline void *GetBotMemoryAddress(void)
 
 bool VMToOSInterface::CreateDoubleMemoryMapper(void **pHandle, size_t *pMaxExecutableCodeSize)
 {
+    if (minipal_detect_rosetta())
+    {
+        // Rosetta doesn't support double mapping correctly. WINE on macOS ARM64 can be running under Rosetta.
+        return false;
+    }
+
     *pMaxExecutableCodeSize = (size_t)MaxDoubleMappedSize;
     *pHandle = CreateFileMapping(
                  INVALID_HANDLE_VALUE,    // use paging file

src/native/minipal/cpufeatures.c

@@ -4,6 +4,8 @@
 #include <stdint.h>
 #include <stdbool.h>
 #include <stddef.h>
+#include <stdio.h>
+#include <string.h>
 
 #include "cpufeatures.h"
 #include "cpuid.h"
@@ -473,3 +475,36 @@ int minipal_getcpufeatures(void)
 
     return result;
 }
+
+// Detect if the current process is running under the Apple Rosetta x64 emulator
+bool minipal_detect_rosetta(void)
+{
+#if defined(HOST_AMD64) || defined(HOST_X86)
+    // Check for CPU brand indicating emulation
+    int regs[4];
+    char brand[49];
+
+    // Get the maximum value for extended function CPUID info
+    __cpuid(regs, (int)0x80000000);
+    if ((unsigned int)regs[0] < 0x80000004)
+    {
+        return false; // Extended CPUID not supported
+    }
+
+    // Retrieve the CPU brand string
+    for (unsigned int i = 0x80000002; i <= 0x80000004; ++i)
+    {
+        __cpuid(regs, (int)i);
+        memcpy(brand + (i - 0x80000002) * sizeof(regs), regs, sizeof(regs));
+    }
+    brand[sizeof(brand) - 1] = '\0';
+
+    // Check if CPU brand indicates emulation
+    if (strstr(brand, "VirtualApple") != NULL)
+    {
+        return true;
+    }
+#endif // HOST_AMD64 || HOST_X86
+
+    return false;
+}

src/native/minipal/cpufeatures.h

@@ -77,6 +77,7 @@ extern "C"
 #endif // __cplusplus
 
 int minipal_getcpufeatures(void);
+bool minipal_detect_rosetta(void);
 
 #ifdef __cplusplus
 }