Paul Gofman : ntdll: Do not use extended context in RtlCopyContext() if extended state is not copied.

[Alexandre Julliard]

Module: wine
Branch: stable
Commit: 349838884e6460a0a6d7d04e4a6e721bf0e9d409
URL:    https://gitlab.winehq.org/wine/wine/-/commit/349838884e6460a0a6d7d04e4a6e721...

Author: Paul Gofman <pgofman(a)codeweavers.com>
Date:   Wed Jan 11 12:32:58 2023 -0600

ntdll: Do not use extended context in RtlCopyContext() if extended state is not copied.

Wine-Bug: https://bugs.winehq.org/show_bug.cgi?id=54289
(cherry picked from commit a98319d0c58cc448b14037cae32d042adfedd94d)

---

 dlls/ntdll/exception.c       | 12 ++++++++++--
 dlls/ntdll/tests/exception.c | 20 ++++++++++++++++++++
 2 files changed, 30 insertions(+), 2 deletions(-)

diff --git a/dlls/ntdll/exception.c b/dlls/ntdll/exception.c
index fa30118f142..556b424ac6e 100644
--- a/dlls/ntdll/exception.c
+++ b/dlls/ntdll/exception.c
@@ -994,6 +994,7 @@ NTSTATUS WINAPI RtlCopyContext( CONTEXT *dst, DWORD context_flags, CONTEXT *src
 {
     DWORD context_size, arch_flag, flags_offset, dst_flags, src_flags;
     static const DWORD arch_mask = CONTEXT_i386 | CONTEXT_AMD64;
+    const struct context_parameters *p;
     BYTE *d, *s;
 
     TRACE("dst %p, context_flags %#lx, src %p.\n", dst, context_flags, src);
@@ -1026,8 +1027,15 @@ NTSTATUS WINAPI RtlCopyContext( CONTEXT *dst, DWORD context_flags, CONTEXT *src
     context_flags &= src_flags;
     if (context_flags & ~dst_flags & 0x40) return STATUS_BUFFER_OVERFLOW;
 
-    return RtlCopyExtendedContext( (CONTEXT_EX *)(d + context_size), context_flags,
-                                   (CONTEXT_EX *)(s + context_size) );
+    if (context_flags & 0x40)
+        return RtlCopyExtendedContext( (CONTEXT_EX *)(d + context_size), context_flags,
+                                       (CONTEXT_EX *)(s + context_size) );
+
+    if (!(p = context_get_parameters( context_flags )))
+        return STATUS_INVALID_PARAMETER;
+
+    context_copy_ranges( d, context_flags, s, p );
+    return STATUS_SUCCESS;
 }
 
 
diff --git a/dlls/ntdll/tests/exception.c b/dlls/ntdll/tests/exception.c
index 4bf2e4ec78e..1f3b7359a13 100644
--- a/dlls/ntdll/tests/exception.c
+++ b/dlls/ntdll/tests/exception.c
@@ -10496,6 +10496,26 @@ static void test_copy_context(void)
 
     enabled_features = pRtlGetEnabledExtendedFeatures(~(ULONG64)0);
 
+    memset(dst_context_buffer, 0xdd, sizeof(dst_context_buffer));
+    memset(src_context_buffer, 0xcc, sizeof(src_context_buffer));
+
+    status = pRtlInitializeExtendedContext(src_context_buffer, CONTEXT_ALL | CONTEXT_XSTATE, &src_ex);
+    if (!status)
+    {
+        src = pRtlLocateLegacyContext(src_ex, NULL);
+        dst = (CONTEXT *)dst_context_buffer;
+        dst->ContextFlags = CONTEXT_ALL;
+        status = pRtlCopyContext(dst, dst->ContextFlags, src);
+        ok(!status, "Got status %#lx.\n", status);
+        check_changes_in_range((BYTE *)dst, CONTEXT_ALL & CONTEXT_AMD64 ? &ranges_amd64[0] : &ranges_x86[0],
+                CONTEXT_ALL, sizeof(CONTEXT));
+    }
+    else
+    {
+        ok(status == STATUS_NOT_SUPPORTED, "Got status %#lx.\n", status);
+        skip("Extended context is not supported.\n");
+    }
+
     for (i = 0; i < ARRAY_SIZE(tests); ++i)
     {
         flags = tests[i];