CreateRemoteThread, doesn't start a thread - c

Question

I use this function as usual, but the debug traces (OutputDebugString) don't work from injecting dlls. And in the target application no thread is created (I look through the process hacker)
GetlastError says 0
CreateRemoteThread says tid
but WaitForSingleObject exits immediately (why if all ok!?)
... I'm confused %
OS windows 10 x64
app and dll - x86
code dll is:
#include <stdio.h>
#include <windows.h>
WINAPI DllMain(HINSTANCE h, DWORD reason, LPVOID res)
{
CHAR pszMessage[1024] = { 0 };
sprintf(pszMessage, ("L2Proj: GetCurrentProcessId() %d, hModule 0x%p, nReason %d\r\n"), GetCurrentProcessId(), h, reason);
OutputDebugString(pszMessage);
switch(reason) {
case DLL_PROCESS_ATTACH:
//MessageBoxA(NULL, "inject success", "done", MB_OK);
TerminateProcess(GetCurrentProcess(), -1);
break;
}
return TRUE;
}
PS TerminateProcess in dll doesn't work either
PPS GetExitCodeThread() after WaitForSingleObject ends is 0
What it the problem with?
ADDED
APP code is:
NOTE: This is just test code (no control over return values ​​/ wrong label name codestyle etc.), pls do not tell me about it.
I wrote step by step in the comments which functions return which values
// process of course has access
HANDLE hProcess = OpenProcess(PROCESS_ALL_ACCESS, FALSE, entry.th32ProcessID);
// handle is valid
if(!hProcess) {
return GetLastError();
}
DWORD id;
char str[] = "G:\\workspace\\proj\\test.dll";
void *l = (void*)GetProcAddress(
GetModuleHandle("kernel32.dll"), "LoadLibraryA");
// addr is valid
if(!l) {
return 35;
}
DWORD str_size = strlen(str) + 1;
// memory addr is valid
LPVOID lp = VirtualAllocEx(hProcess, NULL, str_size, MEM_COMMIT |
MEM_RESERVE, PAGE_READWRITE);
BOOL res = WriteProcessMemory(hProcess, lp, str, str_size, NULL);
// res is true
HANDLE h = CreateRemoteThread(hProcess,
NULL,
0,
(LPTHREAD_START_ROUTINE)l,
lp,
0,
&id);
// handle is valid
// id is valid (tid remote thread)
if(!h) {
return GetLastError();
}
DWORD err = GetLastError();
CHAR pszMessage[1024] = { 0 };
sprintf(pszMessage, ("L2Proj: GetProcessId() %d\r\n"), id);
OutputDebugString(pszMessage);
// ends immediately (no waiting)
WaitForSingleObject(h, INFINITE);
GetExitCodeThread(h, &id);
//id is 0 (exit code)
sprintf(pszMessage, ("L2Proj: GetExitCodeThread() %d (GetLastError=%d)\r\n"), id, err);
OutputDebugString(pszMessage);
// the only error after this function (VirtualFreeEx)
// GetLastError gives 87 (0x57) - ERROR_INVALID_PARAMETER
VirtualFreeEx(hProcess, lp, 0, MEM_RELEASE);
CloseHandle(h);
CloseHandle(hProcess);
I forgot, i use g++ (GCC) 9.3.0 - maybe the problem is because of this?

Answer 1

I solved the problem, just change the compiler.
Yes, the problem was with the compiler, everything works fine on the Microsoft compiler.
Thanks for answers.
problem in you not use debugger – RbMm yesterday
and yes, I always use the debugger, thanks a lot ...