Проблема с хуком pr_write

typedef int (*PR_Write)(void* fd, const void* buf, int amount);
PR_Write old = (PR_Write)(ProcAddress);
 
int HookedPR_Write(void* fd, char* buf, int amount) {
    
    MessageBoxA(NULL,"hooked func","",MB_OK);   
    return old(fd, buf, amount);
}
 
BYTE* Trampoline(BYTE* src, BYTE* dst, int len) {
    BYTE    patch[5];
    BYTE* addr = (BYTE*)VirtualAlloc(NULL, len, MEM_RESERVE | MEM_COMMIT, PAGE_EXECUTE_READWRITE);
    SIZE_T written;
    memcpy_s(addr, len, src, len);
    uintptr_t gatewayrelative = src - addr - 5;
 
    memcpy_s(patch, 1, "\xE9", 1);
    
    *(uintptr_t*)(patch + 1) = gatewayrelative;
    
    if (!WriteProcessMemory(GetCurrentProcess(), addr + len, patch, 5, &written))
        MessageBoxA(NULL, "WriteProcessMemory error", "", MB_OK);
    Detour(src, dst, len);
    return addr;
}
 
void Detour(BYTE* src, BYTE* dst, int len) {
    BYTE patch[11];
    SIZE_T written;
    
    uintptr_t relative_addr = dst - src - 5;
    memcpy_s(patch, 1, "\xE9", 1);
    *(uintptr_t*)(patch + 1) = relative_addr;
    memset(patch + 5, 0x90, len - 5);
    if (!WriteProcessMemory(GetCurrentProcess(), ProcAddress, patch, sizeof(patch), &written))
        MessageBoxA(NULL, "WriteProcessMemory detour error", "Caption", MB_OK); 
}
 
 
BOOL APIENTRY DllMain(HMODULE hModule, DWORD  ul_reason_for_call, LPVOID lpReserved)
{
    ProcAddress = (void*)GetProcAddress(LoadLibraryA("nss3.dll"), "PR_Write");
    int stopSize = 0;
    while (*((BYTE*)ProcAddress + stopSize) != 0xFF) {
        stopSize++;
    }
    if (ul_reason_for_call == DLL_PROCESS_ATTACH)
    {
        if (ProcAddress != NULL) {
            old = (PR_Write)Trampoline((BYTE*)ProcAddress, (BYTE*)HookedPR_Write, stopSize);
        }
    }
    return TRUE;
}