[PATCH 0/1] MR10021: ntdll: Don't fix gsbase on execution fault exception.

[Piotr Caban (＠piotr)]

-- 
https://gitlab.winehq.org/wine/wine/-/merge_requests/10021

[PATCH 1/1] ntdll: Don't fix gsbase on execution fault exception.

[Piotr Caban]

From: Piotr Caban <[e-mail]>

Fixes Diablo II: Resurrected infinite gsbase fixup loop on Intel Mac.
---
 dlls/ntdll/tests/exception.c    | 26 +++++++++++++++++++++++++-
 dlls/ntdll/unix/signal_x86_64.c |  1 +
 2 files changed, 26 insertions(+), 1 deletion(-)

diff --git a/dlls/ntdll/tests/exception.c b/dlls/ntdll/tests/exception.c
index 24b4215315f..dfc1581492e 100644
--- a/dlls/ntdll/tests/exception.c
+++ b/dlls/ntdll/tests/exception.c
@@ -2782,6 +2782,7 @@ static const struct exception
     NTSTATUS alt_status;    /* alternative status code */
     DWORD    alt_nb_params; /* alternative number of parameters */
     ULONG64  alt_params[4]; /* alternative parameters */
+    DWORD    access;
 } exceptions[] =
 {
 /* 0 */
@@ -2941,6 +2942,11 @@ static const struct exception
         0x30, 0x00, 0x00, 0x00,
         0xc3 },                                /* ret */
       8, 0, STATUS_SUCCESS, 0 },
+    { { 0x65, 0x48, 0x8b, 0x04, 0x25,          /* movq %gs:0x30,%rax (NtCurrentTeb) */
+        0x30, 0x00, 0x00, 0x00,
+        0xc3 },                                /* ret */
+      0, 0, STATUS_ACCESS_VIOLATION, 2, { EXCEPTION_EXECUTE_FAULT },
+      0, 0, { 0 }, PAGE_READONLY },
 };
 
 static int got_exception;
@@ -3065,6 +3071,17 @@ static DWORD WINAPI prot_fault_handler( EXCEPTION_RECORD *rec, ULONG64 frame,
         goto skip_params;
     }
 
+    if (except->nb_params == 2 && except->params[0] == EXCEPTION_EXECUTE_FAULT)
+    {
+        ok( rec->ExceptionInformation[0] == except->params[0],
+            "Wrong parameter 0: %Ix/%Ix\n",
+            rec->ExceptionInformation[0], except->params[0] );
+        ok( rec->ExceptionInformation[1] == (DWORD_PTR)code_mem + except->offset,
+            "Wrong parameter 1: %Ix/%Ix\n",
+            rec->ExceptionInformation[1], (DWORD_PTR)code_mem + except->offset);
+        goto skip_params;
+    }
+
     if (except->alt_status == 0 || rec->ExceptionCode != except->alt_status)
     {
         for (i = 0; i < rec->NumberParameters; i++)
@@ -3083,6 +3100,13 @@ static DWORD WINAPI prot_fault_handler( EXCEPTION_RECORD *rec, ULONG64 frame,
 skip_params:
     winetest_pop_context();
 
+    if (except->access == PAGE_READONLY)
+    {
+        DWORD old_prot;
+
+        VirtualProtect(code_mem, 1, PAGE_EXECUTE_READ, &old_prot);
+    }
+
     context->Rip = (DWORD_PTR)code_mem + except->offset + except->length;
     return ExceptionContinueExecution;
 }
@@ -3518,7 +3542,7 @@ static void test_prot_fault(void)
     {
         got_exception = 0;
         run_exception_test(prot_fault_handler, &exceptions[i], &exceptions[i].code,
-                           sizeof(exceptions[i].code), 0);
+                           sizeof(exceptions[i].code), exceptions[i].access);
         ok( got_exception == (exceptions[i].status != 0),
             "%u: bad exception count %d\n", i, got_exception );
     }
diff --git a/dlls/ntdll/unix/signal_x86_64.c b/dlls/ntdll/unix/signal_x86_64.c
index 62be4809aaa..0c62e8a1ad4 100644
--- a/dlls/ntdll/unix/signal_x86_64.c
+++ b/dlls/ntdll/unix/signal_x86_64.c
@@ -2308,6 +2308,7 @@ static inline BOOL check_invalid_gsbase( ucontext_t *ucontext )
     ULONG_PTR cur_gsbase = 0;
 
     if (CS_sig(ucontext) != cs64_sel) return FALSE;
+    if (((ERROR_sig(ucontext) >> 1) & 0x09) == EXCEPTION_EXECUTE_FAULT) return FALSE;
 
 #ifdef __linux__
     if (user_shared_data->ProcessorFeatures[PF_RDWRFSGSBASE_AVAILABLE])
-- 
GitLab

https://gitlab.winehq.org/wine/wine/-/merge_requests/10021