Signed-off-by: Paul Gofman pgofman@codeweavers.com --- dlls/ntdll/signal_i386.c | 9 ++- dlls/ntdll/tests/exception.c | 111 +++++++++++++++++++++++++++++++++- dlls/ntdll/unix/signal_i386.c | 9 +-- 3 files changed, 121 insertions(+), 8 deletions(-)
diff --git a/dlls/ntdll/signal_i386.c b/dlls/ntdll/signal_i386.c index 676329c5bd2..aa19c632be2 100644 --- a/dlls/ntdll/signal_i386.c +++ b/dlls/ntdll/signal_i386.c @@ -198,7 +198,7 @@ static NTSTATUS call_stack_handlers( EXCEPTION_RECORD *rec, CONTEXT *context ) /******************************************************************* * KiUserExceptionDispatcher (NTDLL.@) */ -NTSTATUS WINAPI KiUserExceptionDispatcher( EXCEPTION_RECORD *rec, CONTEXT *context ) +NTSTATUS WINAPI dispatch_exception( EXCEPTION_RECORD *rec, CONTEXT *context ) { NTSTATUS status; DWORD c; @@ -243,6 +243,13 @@ NTSTATUS WINAPI KiUserExceptionDispatcher( EXCEPTION_RECORD *rec, CONTEXT *conte return NtRaiseException( rec, context, FALSE ); }
+__ASM_GLOBAL_FUNC( KiUserExceptionDispatcher@8, + /* hotpatch prologue. */ + "push %ebp\n\t" + "mov %esp,%ebp\n\t" + "pop %ebp\n\t" + "call " __ASM_NAME("dispatch_exception") "\n\t" + "int3")
/*********************************************************************** * save_fpu diff --git a/dlls/ntdll/tests/exception.c b/dlls/ntdll/tests/exception.c index 95d25375f77..a27dee21f00 100644 --- a/dlls/ntdll/tests/exception.c +++ b/dlls/ntdll/tests/exception.c @@ -1660,6 +1660,114 @@ static void test_thread_context(void) #undef COMPARE }
+static BYTE saved_KiUserExceptionDispatcher_bytes[7]; +static void *pKiUserExceptionDispatcher; +static BOOL hook_called; +static void *hook_KiUserExceptionDispatcher_eip; +static void *dbg_except_continue_handler_eip; +static void *hook_exception_address; + +static DWORD dbg_except_continue_handler(EXCEPTION_RECORD *rec, EXCEPTION_REGISTRATION_RECORD *frame, + CONTEXT *context, EXCEPTION_REGISTRATION_RECORD **dispatcher) +{ + ok(hook_called, "Hook was not called.\n"); + got_exception = 1; + dbg_except_continue_handler_eip = (void *)context->Eip; + ++context->Eip; + return ExceptionContinueExecution; +} + +/* Use CDECL to leave arguments on stack. */ +void CDECL hook_KiUserExceptionDispatcher(EXCEPTION_RECORD *rec, CONTEXT *context) +{ + trace("rec %p, context %p.\n", rec, context); + trace("context->Eip %#x, context->Esp %#x, ContextFlags %#x.\n", + context->Eip, context->Esp, context->ContextFlags); + + hook_called = TRUE; + /* Broken on Win2008, probably rec offset in stack is different. */ + ok(rec->ExceptionCode == 0x80000003 || broken(!rec->ExceptionCode), + "Got unexpected ExceptionCode %#x.\n", rec->ExceptionCode); + + hook_KiUserExceptionDispatcher_eip = (void *)context->Eip; + hook_exception_address = rec->ExceptionAddress; + memcpy(pKiUserExceptionDispatcher, saved_KiUserExceptionDispatcher_bytes, + sizeof(saved_KiUserExceptionDispatcher_bytes)); +} + +static void test_kiuserexceptiondispatcher(void) +{ + HMODULE hntdll = GetModuleHandleA("ntdll.dll"); + static const BYTE except_code[] = + { + 0xcc, /* int3 */ + 0xc3, /* ret */ + }; + static BYTE hook_trampoline[] = + { + 0xff, 0x15, + /* offset: 2 bytes */ + 0x00, 0x00, 0x00, 0x00, /* callq *addr */ /* call hook implementation. */ + + 0xff, 0x25, + /* offset: 8 bytes */ + 0x00, 0x00, 0x00, 0x00, /* jmpq *addr */ /* jump to original function. */ + }; + void *phook_KiUserExceptionDispatcher = hook_KiUserExceptionDispatcher; + void *phook_trampoline = hook_trampoline; + DWORD old_protect1, old_protect2; + BYTE *ptr; + BOOL ret; + + pKiUserExceptionDispatcher = (void *)GetProcAddress(hntdll, "KiUserExceptionDispatcher"); + if (!pKiUserExceptionDispatcher) + { + win_skip("KiUserExceptionDispatcher is not available.\n"); + return; + } + + *(unsigned int *)(hook_trampoline + 2) = (ULONG_PTR)&phook_KiUserExceptionDispatcher; + *(unsigned int *)(hook_trampoline + 8) = (ULONG_PTR)&pKiUserExceptionDispatcher; + + ret = VirtualProtect(hook_trampoline, ARRAY_SIZE(hook_trampoline), PAGE_EXECUTE_READWRITE, &old_protect1); + ok(ret, "Got unexpected ret %#x, GetLastError() %u.\n", ret, GetLastError()); + + ret = VirtualProtect(pKiUserExceptionDispatcher, sizeof(saved_KiUserExceptionDispatcher_bytes), + PAGE_EXECUTE_READWRITE, &old_protect2); + ok(ret, "Got unexpected ret %#x, GetLastError() %u.\n", ret, GetLastError()); + + memcpy(saved_KiUserExceptionDispatcher_bytes, pKiUserExceptionDispatcher, + sizeof(saved_KiUserExceptionDispatcher_bytes)); + ptr = (BYTE *)pKiUserExceptionDispatcher; + /* mov hook_trampoline, %eax */ + *ptr++ = 0xa1; + *(void **)ptr = &phook_trampoline; + ptr += sizeof(void *); + /* jmp *eax */ + *ptr++ = 0xff; + *ptr++ = 0xe0; + + got_exception = 0; + run_exception_test(dbg_except_continue_handler, NULL, except_code, ARRAY_SIZE(except_code), + PAGE_EXECUTE_READ); + ok(got_exception, "Handler was not called.\n"); + ok(hook_called, "Hook was not called.\n"); + + ok(hook_exception_address == code_mem || broken(!hook_exception_address) /* Win2008 */, + "Got unexpected exception address %p, expected %p.\n", + hook_exception_address, code_mem); + todo_wine ok(hook_KiUserExceptionDispatcher_eip == code_mem, "Got unexpected exception address %p, expected %p.\n", + hook_KiUserExceptionDispatcher_eip, code_mem); + ok(dbg_except_continue_handler_eip == code_mem, "Got unexpected exception address %p, expected %p.\n", + dbg_except_continue_handler_eip, code_mem); + + ret = VirtualProtect(pKiUserExceptionDispatcher, sizeof(saved_KiUserExceptionDispatcher_bytes), + old_protect2, &old_protect2); + ok(ret, "Got unexpected ret %#x, GetLastError() %u.\n", ret, GetLastError()); + ret = VirtualProtect(hook_trampoline, ARRAY_SIZE(hook_trampoline), old_protect1, &old_protect1); + ok(ret, "Got unexpected ret %#x, GetLastError() %u.\n", ret, GetLastError()); +} + #elif defined(__x86_64__)
#define is_wow64 0 @@ -3751,7 +3859,6 @@ START_TEST(exception) test_suspend_thread(); test_suspend_process(); test_unload_trace(); - test_kiuserexceptiondispatcher();
if (pRtlAddFunctionTable && pRtlDeleteFunctionTable && pRtlInstallFunctionTableCallback && pRtlLookupFunctionEntry) test_dynamic_unwind(); @@ -3766,5 +3873,7 @@ START_TEST(exception)
#endif
+ test_kiuserexceptiondispatcher(); + VirtualFree(code_mem, 0, MEM_RELEASE); } diff --git a/dlls/ntdll/unix/signal_i386.c b/dlls/ntdll/unix/signal_i386.c index 730d0b1cb32..29d0e2adeaf 100644 --- a/dlls/ntdll/unix/signal_i386.c +++ b/dlls/ntdll/unix/signal_i386.c @@ -428,7 +428,6 @@ static inline int set_thread_area( struct modify_ldt_s *ptr ) /* stack layout when calling an exception raise function */ struct stack_layout { - void *ret_addr; /* return address from raise_generic_exception */ EXCEPTION_RECORD *rec_ptr; /* first arg for raise_generic_exception */ CONTEXT *context_ptr; /* second arg for raise_generic_exception */ CONTEXT context; @@ -1583,15 +1582,13 @@ static void setup_raise_exception( ucontext_t *sigcontext, struct stack_layout * FS_sig(sigcontext) = get_fs(); GS_sig(sigcontext) = get_gs(); SS_sig(sigcontext) = get_ds(); - stack->ret_addr = (void *)0xdeadbabe; /* KiUserExceptionDispatcher must not return */ stack->rec_ptr = &stack->rec; /* arguments for KiUserExceptionDispatcher */ stack->context_ptr = &stack->context; }
-void WINAPI call_user_exception_dispatcher( EXCEPTION_RECORD *rec, CONTEXT *context ) -{ - pKiUserExceptionDispatcher( rec, context ); -} +__ASM_GLOBAL_FUNC( call_user_exception_dispatcher, + "add $4,%esp\n\t" + "jmp *pKiUserExceptionDispatcher\n\t")
/********************************************************************** * get_fpu_code