Alexandre Julliard : wow64: Keep track of APC stack frames, similarly to user callback frames.

[Alexandre Julliard]

Module: wine
Branch: master
Commit: c244fe3d2749696b8c335c1b65b9d8291f7f0e6a
URL:    https://gitlab.winehq.org/wine/wine/-/commit/c244fe3d2749696b8c335c1b65b9d82...

Author: Alexandre Julliard <julliard(a)winehq.org>
Date:   Tue Mar  7 17:22:46 2023 +0100

wow64: Keep track of APC stack frames, similarly to user callback frames.

And use the appropriate frame to restore the context in NtContinue.

---

 dlls/wow64/syscall.c | 31 ++++++++++++++++++++++---------
 include/winternl.h   |  1 +
 2 files changed, 23 insertions(+), 9 deletions(-)

diff --git a/dlls/wow64/syscall.c b/dlls/wow64/syscall.c
index de5a42aec4f..d2bb054b6d0 100644
--- a/dlls/wow64/syscall.c
+++ b/dlls/wow64/syscall.c
@@ -84,6 +84,13 @@ struct user_callback_frame
     __wine_jmp_buf              jmpbuf;
 };
 
+/* stack frame for user APCs */
+struct user_apc_frame
+{
+    struct user_apc_frame *prev_frame;
+    CONTEXT               *context;
+    void                  *wow_context;
+};
 
 SYSTEM_DLL_INIT_BLOCK *pLdrSystemDllInitBlock = NULL;
 
@@ -416,8 +423,14 @@ NTSTATUS WINAPI wow64_NtContinue( UINT *args )
     BOOLEAN alertable = get_ulong( &args );
 
     NTSTATUS status = get_context_return_value( context );
+    struct user_apc_frame *frame = NtCurrentTeb()->TlsSlots[WOW64_TLS_APCLIST];
 
     pBTCpuSetContext( GetCurrentThread(), GetCurrentProcess(), NULL, context );
+
+    while (frame && frame->wow_context != context) frame = frame->prev_frame;
+    NtCurrentTeb()->TlsSlots[WOW64_TLS_APCLIST] = frame ? frame->prev_frame : NULL;
+    if (frame) NtContinue( frame->context, alertable );
+
     if (alertable) NtTestAlert();
     return status;
 }
@@ -981,13 +994,11 @@ void * WINAPI Wow64AllocateTemp( SIZE_T size )
  */
 void WINAPI Wow64ApcRoutine( ULONG_PTR arg1, ULONG_PTR arg2, ULONG_PTR arg3, CONTEXT *context )
 {
-    NTSTATUS retval;
+    struct user_apc_frame frame;
 
-#ifdef __x86_64__
-    retval = context->Rax;
-#elif defined(__aarch64__)
-    retval = context->X0;
-#endif
+    frame.prev_frame = NtCurrentTeb()->TlsSlots[WOW64_TLS_APCLIST];
+    frame.context    = context;
+    NtCurrentTeb()->TlsSlots[WOW64_TLS_APCLIST] = &frame;
 
     /* cf. 32-bit call_user_apc_dispatcher */
     switch (current_machine)
@@ -1014,10 +1025,11 @@ void WINAPI Wow64ApcRoutine( ULONG_PTR arg1, ULONG_PTR arg2, ULONG_PTR arg3, CON
             stack->arg2 = arg2;
             stack->arg3 = arg3;
             stack->context = ctx;
-            stack->context.Eax = retval;
             ctx.Esp = PtrToUlong( stack );
             ctx.Eip = pLdrSystemDllInitBlock->pKiUserApcDispatcher;
+            frame.wow_context = &stack->context;
             pBTCpuSetContext( GetCurrentThread(), GetCurrentProcess(), NULL, &ctx );
+            cpu_simulate();
         }
         break;
 
@@ -1035,14 +1047,15 @@ void WINAPI Wow64ApcRoutine( ULONG_PTR arg1, ULONG_PTR arg2, ULONG_PTR arg3, CON
             stack = (struct apc_stack_layout *)ULongToPtr( ctx.Sp & ~15 ) - 1;
             stack->func = arg1 >> 32;
             stack->context = ctx;
-            stack->context.R0 = retval;
             ctx.Sp = PtrToUlong( stack );
             ctx.Pc = pLdrSystemDllInitBlock->pKiUserApcDispatcher;
             ctx.R0 = PtrToUlong( &stack->context );
             ctx.R1 = arg1;
             ctx.R2 = arg2;
             ctx.R3 = arg3;
+            frame.wow_context = &stack->context;
             pBTCpuSetContext( GetCurrentThread(), GetCurrentProcess(), NULL, &ctx );
+            cpu_simulate();
         }
         break;
     }
@@ -1112,7 +1125,7 @@ NTSTATUS WINAPI Wow64KiUserCallbackDispatcher( ULONG id, void *args, ULONG len,
             memcpy( args_data, args, len );
 
             ctx.R0 = id;
-            ctx.R1 = PtrToUlong( args );
+            ctx.R1 = PtrToUlong( args_data );
             ctx.R2 = len;
             ctx.Sp = PtrToUlong( args_data );
             ctx.Pc = pLdrSystemDllInitBlock->pKiUserCallbackDispatcher;
diff --git a/include/winternl.h b/include/winternl.h
index 95abf79812b..f2992b82857 100644
--- a/include/winternl.h
+++ b/include/winternl.h
@@ -1083,6 +1083,7 @@ typedef struct _TEB64
 #define WOW64_TLS_CPURESERVED      1
 #define WOW64_TLS_TEMPLIST         3
 #define WOW64_TLS_USERCALLBACKDATA 5
+#define WOW64_TLS_APCLIST          7
 #define WOW64_TLS_FILESYSREDIR     8
 #define WOW64_TLS_MAX_NUMBER       19