From fb5cfacce5c6450a4b0b0edafc9e9cc21d73552e Mon Sep 17 00:00:00 2001
From: Alexandre Julliard <julliard@winehq.org>
Date: Tue, 11 Jul 2023 13:43:26 +0200
Subject: [PATCH] ntdll: Return the 32-bit PEB for
 NtQueryInformationProcess(ProcessWow64Information).

---
 dlls/ntdll/tests/info.c   |  5 ++++-
 dlls/ntdll/tests/wow64.c  |  7 +++++++
 dlls/ntdll/unix/process.c | 11 ++++++-----
 3 files changed, 17 insertions(+), 6 deletions(-)

diff --git a/dlls/ntdll/tests/info.c b/dlls/ntdll/tests/info.c
index fafbd1ac997..877978b6b3c 100644
--- a/dlls/ntdll/tests/info.c
+++ b/dlls/ntdll/tests/info.c
@@ -1735,7 +1735,8 @@ static void test_query_process_wow64(void)
     status = NtQueryInformationProcess(GetCurrentProcess(), ProcessWow64Information, pbi, sizeof(ULONG_PTR), NULL);
     ok( status == STATUS_SUCCESS, "Expected STATUS_SUCCESS, got %08lx\n", status);
     ok( is_wow64 == (pbi[0] != 0), "is_wow64 %x, pbi[0] %Ix\n", is_wow64, pbi[0]);
-    ok( pbi[0] != dummy, "pbi[0] %Ix\n", pbi[0]);
+    if (is_wow64)
+        ok( (void *)pbi[0] == NtCurrentTeb()->Peb, "pbi[0] %Ix / %p\n", pbi[0], NtCurrentTeb()->Peb);
     ok( pbi[1] == dummy, "pbi[1] changed to %Ix\n", pbi[1]);
     /* Test written size on 64 bit by checking high 32 bit buffer */
     if (sizeof(ULONG_PTR) > sizeof(DWORD))
@@ -1750,6 +1751,8 @@ static void test_query_process_wow64(void)
     status = NtQueryInformationProcess(GetCurrentProcess(), ProcessWow64Information, pbi, sizeof(ULONG_PTR), &ReturnLength);
     ok( status == STATUS_SUCCESS, "Expected STATUS_SUCCESS, got %08lx\n", status);
     ok( is_wow64 == (pbi[0] != 0), "is_wow64 %x, pbi[0] %Ix\n", is_wow64, pbi[0]);
+    if (is_wow64)
+        ok( (void *)pbi[0] == NtCurrentTeb()->Peb, "pbi[0] %Ix / %p\n", pbi[0], NtCurrentTeb()->Peb);
     ok( pbi[1] == dummy, "pbi[1] changed to %Ix\n", pbi[1]);
     ok( ReturnLength == sizeof(ULONG_PTR), "Inconsistent length %ld\n", ReturnLength);
 
diff --git a/dlls/ntdll/tests/wow64.c b/dlls/ntdll/tests/wow64.c
index b99b22fb1af..46523d47c46 100644
--- a/dlls/ntdll/tests/wow64.c
+++ b/dlls/ntdll/tests/wow64.c
@@ -277,6 +277,7 @@ static void test_peb_teb(void)
     PEB32 peb32;
     RTL_USER_PROCESS_PARAMETERS params;
     RTL_USER_PROCESS_PARAMETERS32 params32;
+    ULONG_PTR peb_ptr;
 
     Wow64DisableWow64FsRedirection( &redir );
 
@@ -317,6 +318,12 @@ static void test_peb_teb(void)
         ok( !status, "ProcessBasicInformation failed %lx\n", status );
         ok( proc_info.PebBaseAddress == teb.Peb, "wrong peb %p / %p\n", proc_info.PebBaseAddress, teb.Peb );
 
+        status = NtQueryInformationProcess( pi.hProcess, ProcessWow64Information,
+                                            &peb_ptr, sizeof(peb_ptr), NULL );
+        ok( !status, "ProcessWow64Information failed %lx\n", status );
+        ok( (void *)peb_ptr == (is_wow64 ? teb.Peb : ULongToPtr(teb32.Peb)),
+            "wrong peb %p\n", (void *)peb_ptr );
+
         if (!ReadProcessMemory( pi.hProcess, proc_info.PebBaseAddress, &peb, sizeof(peb), &res )) res = 0;
         ok( res == sizeof(peb), "wrong len %Ix\n", res );
         ok( !peb.BeingDebugged, "BeingDebugged is %u\n", peb.BeingDebugged );
diff --git a/dlls/ntdll/unix/process.c b/dlls/ntdll/unix/process.c
index 140a93583b4..30bd6f083bd 100644
--- a/dlls/ntdll/unix/process.c
+++ b/dlls/ntdll/unix/process.c
@@ -1430,9 +1430,8 @@ NTSTATUS WINAPI NtQueryInformationProcess( HANDLE handle, PROCESSINFOCLASS class
     case ProcessWow64Information:
         len = sizeof(ULONG_PTR);
         if (size != len) return STATUS_INFO_LENGTH_MISMATCH;
-        else if (!info) ret = STATUS_ACCESS_VIOLATION;
-        else if (!handle) ret = STATUS_INVALID_HANDLE;
-        else if (handle == GetCurrentProcess()) *(ULONG_PTR *)info = is_wow64();
+        if (handle == GetCurrentProcess())
+            *(ULONG_PTR *)info = is_old_wow64() ? (ULONG_PTR)peb : (ULONG_PTR)wow_peb;
         else
         {
             ULONG_PTR val = 0;
@@ -1440,10 +1439,12 @@ NTSTATUS WINAPI NtQueryInformationProcess( HANDLE handle, PROCESSINFOCLASS class
             SERVER_START_REQ( get_process_info )
             {
                 req->handle = wine_server_obj_handle( handle );
-                if (!(ret = wine_server_call( req ))) val = (reply->machine != native_machine);
+                ret = wine_server_call( req );
+                if (!ret && !is_machine_64bit( reply->machine ) && is_machine_64bit( native_machine ))
+                    val = reply->peb + 0x1000;
             }
             SERVER_END_REQ;
-            *(ULONG_PTR *)info = val;
+            if (!ret) *(ULONG_PTR *)info = val;
         }
         break;