[PATCH 0/4] MR4792: ntdll/tests: Fix xstate tests failing on Windows 11 and CPU with more XSAVE features.

[Jinoh Kang (＠iamahuman)]

Follow-up of MR !1939.

[PATCH 1/4] ntdll/tests: Fix x86-32 extended context end offset in test_copy_context().

[Jinoh Kang]

From: Jinoh Kang

The penultimate element of `ranges_x86` array has an incorrect value: it
should be *at least* 0x2f0, which is the minimum size of an extended
context.

Fix this by setting it to 0x440, which is the minimum size of an
extended context *with* CONTEXT_I386_XSTATE.  This is consistent with
`ranges_amd64`, the penultimate element of which has the minimum size of
an extended context *with* CONTEXT_AMD64_XSTATE.

Note that the incorrect value does not always lead to a test failure,
since check_changes_in_range_() effectively ignores range `start`s that
are not in order.  Reproducing the failure requires a system with a
sufficiently large XSAVE area; specifically, the following condition is
necessary for check_changes_in_range_() to pick up the wrong value:

0x2cc < 0x294 + src_ex->XState.Length - sizeof(XSTATE).
---
 dlls/ntdll/tests/exception.c | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/dlls/ntdll/tests/exception.c b/dlls/ntdll/tests/exception.c
index bac571b2733..79a65dadab9 100644
--- a/dlls/ntdll/tests/exception.c
+++ b/dlls/ntdll/tests/exception.c
@@ -11848,7 +11848,7 @@ static void test_copy_context(void)
     static struct modified_range ranges_x86[] =
     {
         {0x0, ~0}, {0x4, 0x10}, {0x1c, 0x8}, {0x8c, 0x4}, {0x9c, 0x2}, {0xb4, 0x1}, {0xcc, 0x20}, {0x1ec, 0x80000020},
-        {0x2cc, ~0}, {0x294, 0}, {0x1000, 0},
+        {0x2cc, ~0}, {0x440, 0}, {0x1000, 0},
     };
     static const struct modified_range single_range[] =
     {
@@ -11963,7 +11963,7 @@ static void test_copy_context(void)
             if (flags & CONTEXT_AMD64)
                 ranges_amd64[ARRAY_SIZE(ranges_amd64) - 2].start = 0x640 + src_ex->XState.Length - sizeof(XSTATE);
             else
-                ranges_x86[ARRAY_SIZE(ranges_x86) - 2].start = 0x294 + src_ex->XState.Length - sizeof(XSTATE);
+                ranges_x86[ARRAY_SIZE(ranges_x86) - 2].start = 0x440 + src_ex->XState.Length - sizeof(XSTATE);
         }

status = pRtlCopyExtendedContext(dst_ex, flags, src_ex);

[PATCH 2/4] ntdll/tests: Fix incorrect calculation of context length in test_copy_context().

[Jinoh Kang]

From: Jinoh Kang

`(BYTE *)dst_ex - (BYTE *)dst` is the size of the legacy context, but
`dst_ex->All` already contains the legacy context.  Therefore,
`context_length` has the legacy context size added *twice*.

This becomes a problem when `context_length` exceeds
`sizeof(src_context_buffer)`.  This confuses `check_changes_in_range()`,
causing out-of-bounds read and unpredictable test results.
---
 dlls/ntdll/tests/exception.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/dlls/ntdll/tests/exception.c b/dlls/ntdll/tests/exception.c
index 79a65dadab9..9f6bfbd2008 100644
--- a/dlls/ntdll/tests/exception.c
+++ b/dlls/ntdll/tests/exception.c
@@ -11952,7 +11952,7 @@ static void test_copy_context(void)
         *(DWORD *)((BYTE *)dst + flags_offset) = 0;
         *(DWORD *)((BYTE *)src + flags_offset) = 0;

-        context_length = (BYTE *)dst_ex - (BYTE *)dst + dst_ex->All.Length;
+        context_length = dst_ex->All.Length;

if (flags & 0x40)
         {

[PATCH 3/4] ntdll/tests: Don't hard code the maximum XState length in test_extended_context().

[Jinoh Kang]

From: Jinoh Kang

This is required to support systems with a larger XSAVE area.
---
 dlls/ntdll/tests/exception.c | 8 ++++++--
 1 file changed, 6 insertions(+), 2 deletions(-)

diff --git a/dlls/ntdll/tests/exception.c b/dlls/ntdll/tests/exception.c
index 9f6bfbd2008..d98bacd2f16 100644
--- a/dlls/ntdll/tests/exception.c
+++ b/dlls/ntdll/tests/exception.c
@@ -10884,7 +10884,7 @@ static void test_extended_context(void)
     const struct context_parameters *context_arch;

const ULONG64 supported_features = 7, supported_compaction_mask = supported_features | ((ULONG64)1 << 63);
-    ULONG expected_length, expected_length_xstate, context_flags, expected_offset;
+    ULONG expected_length, expected_length_xstate, context_flags, expected_offset, max_xstate_length;
     ULONG64 enabled_features, expected_compaction;
     DECLSPEC_ALIGN(64) BYTE context_buffer2[2048];
     DECLSPEC_ALIGN(64) BYTE context_buffer[2048];
@@ -11511,6 +11511,10 @@ static void test_extended_context(void)
     context_ex = (CONTEXT_EX *)(context + 1);
     xs = (XSTATE *)((BYTE *)context_ex + context_ex->XState.Offset);

+    max_xstate_length = context_ex->XState.Length;
+    ok(max_xstate_length >= sizeof(XSTATE), "XSTATE size: %#lx; min: %#Ix.\n", max_xstate_length, sizeof(XSTATE));
+    ok(!(max_xstate_length % 64), "XSTATE size: %#lx; should be multiple of 64.\n", max_xstate_length);
+
     *(void **)(call_func_code_set_ymm0 + call_func_offsets.func_addr) = RtlCaptureContext;
     *(void **)(call_func_code_set_ymm0 + call_func_offsets.func_param1) = context;
     *(void **)(call_func_code_set_ymm0 + call_func_offsets.func_param2) = (void *)0xdeadbeef;
@@ -11571,7 +11575,7 @@ static void test_extended_context(void)

xs->CompactionMask = 4;
     xs->Mask = compaction_enabled ? 0 : 4;
-    context_ex->XState.Length = sizeof(XSTATE) + 64;
+    context_ex->XState.Length = max_xstate_length + 64;
     bret = func();
     ok(!bret && GetLastError() == ERROR_INVALID_PARAMETER,
             "Got unexpected bret %#x, GetLastError() %lu.\n", bret, GetLastError());

[PATCH 4/4] ntdll/tests: Fix xstate tests failing on Windows 11 and CPU with more XSAVE features.

[Jinoh Kang]

From: Jinoh Kang

---
 dlls/ntdll/tests/exception.c | 6 +++---
 1 file changed, 3 insertions(+), 3 deletions(-)

diff --git a/dlls/ntdll/tests/exception.c b/dlls/ntdll/tests/exception.c
index d98bacd2f16..d659672b48f 100644
--- a/dlls/ntdll/tests/exception.c
+++ b/dlls/ntdll/tests/exception.c
@@ -228,7 +228,7 @@ static enum debugger_stages test_stage;
 #if defined(__i386__) || defined(__x86_64__)
 static void test_debugger_xstate(HANDLE thread, CONTEXT *ctx, enum debugger_stages stage)
 {
-    char context_buffer[sizeof(CONTEXT) + sizeof(CONTEXT_EX) + sizeof(XSTATE) + 1024];
+    char context_buffer[sizeof(CONTEXT) + sizeof(CONTEXT_EX) + sizeof(XSTATE) + 3072];
     CONTEXT_EX *c_ex;
     NTSTATUS status;
     YMMCONTEXT *ymm;
@@ -10886,8 +10886,8 @@ static void test_extended_context(void)
     const ULONG64 supported_features = 7, supported_compaction_mask = supported_features | ((ULONG64)1 << 63);
     ULONG expected_length, expected_length_xstate, context_flags, expected_offset, max_xstate_length;
     ULONG64 enabled_features, expected_compaction;
-    DECLSPEC_ALIGN(64) BYTE context_buffer2[2048];
-    DECLSPEC_ALIGN(64) BYTE context_buffer[2048];
+    DECLSPEC_ALIGN(64) BYTE context_buffer2[4096];
+    DECLSPEC_ALIGN(64) BYTE context_buffer[4096];
     unsigned int i, j, address_offset, test;
     ULONG ret, ret2, length, length2, align;
     ULONG flags, flags_fpx, expected_flags;

[Paul Gofman (＠gofman)]

I run the tests with this MR on one AMD machine here and I am getting this new test failure:
> exception.c:11516: Test failed: XSTATE size: 0x150; should be multiple of 64.

That's both on 64 and 32 bit.

[Paul Gofman (＠gofman)]

I guess it is just the test on this line which is wrong and can be dropped (the XSTATE length is not necessarily a multiple of 64 for a generic set of features).