fix(libkernel_sys): return EFAULT on unwritable mode pointer in sceKernelGetCpumodeGame

core/libs/prx/libkernel_sys/Export.cpp

@@ -385,7 +385,8 @@ int APS5_VABI sceKernelGetOpenPsIdForSystem(void* id) {
 
 int APS5_VABI sceKernelGetCpumodeGame(int* mode) {
     if (mode == nullptr) throw std::runtime_error("sceKernelGetCpumodeGame: a null output faults on the console");
-    *mode = g_gameCpumode.load(std::memory_order_relaxed);
+    const int val = g_gameCpumode.load(std::memory_order_relaxed);
+    if (!GuestCopyOut_nid_no_patch(mode, &val, sizeof(val))) return SCE_KERNEL_ERROR_EFAULT;
     return 0;
 }
 

core/libs/tests/GuestKernelSysCpumode.cpp

@@ -37,6 +37,7 @@ int main() {
     Require(Throws([] { sceKernelSetCpumodeGame(8); }), "an unmeasured mode did not throw");
     Require(Throws([] { sceKernelSetCpumodeGame(-1); }), "a negative mode did not throw");
     Require(Throws([] { sceKernelGetCpumodeGame(nullptr); }), "a null output did not throw");
+    Require(sceKernelGetCpumodeGame(reinterpret_cast<int*>(0x10)) == static_cast<int>(0x8002000Eu), "unwritable mode did not return EFAULT");
     std::puts("game CPU mode tests passed");
     return 0;
 }