From b41566fb31b257d04f6044b01d996f71d2859493 Mon Sep 17 00:00:00 2001
From: Alexandre Julliard <julliard@winehq.org>
Date: Wed, 7 Feb 2024 11:52:30 +0100
Subject: [PATCH] ntdll: Fix stack layout for ARM syscalls.

---
 dlls/ntdll/unix/signal_arm.c |  9 +++++----
 include/wine/asm.h           | 23 ++++-------------------
 2 files changed, 9 insertions(+), 23 deletions(-)

diff --git a/dlls/ntdll/unix/signal_arm.c b/dlls/ntdll/unix/signal_arm.c
index 9ca0569bd62..0f6f81d2ee1 100644
--- a/dlls/ntdll/unix/signal_arm.c
+++ b/dlls/ntdll/unix/signal_arm.c
@@ -1052,7 +1052,10 @@ NTSTATUS call_user_apc_dispatcher( CONTEXT *context, ULONG_PTR arg1, ULONG_PTR a
  */
 void call_raise_user_exception_dispatcher(void)
 {
-    arm_thread_data()->syscall_frame->pc = (DWORD)pKiRaiseUserExceptionDispatcher;
+    struct syscall_frame *frame = arm_thread_data()->syscall_frame;
+
+    frame->sp += 16;
+    frame->pc = (DWORD)pKiRaiseUserExceptionDispatcher;
 }
 
 
@@ -1608,8 +1611,7 @@ __ASM_GLOBAL_FUNC( __wine_syscall_dispatcher,
                    "ldr r1, [r2, #0x1d8]\n\t"       /* arm_thread_data()->syscall_frame */
                    "add r0, r1, #0x10\n\t"
                    "stm r0, {r4-r12,lr}\n\t"
-                   "add r0, sp, #0x10\n\t"
-                   "str r0, [r1, #0x38]\n\t"
+                   "str sp, [r1, #0x38]\n\t"
                    "str r3, [r1, #0x3c]\n\t"
                    "mrs r0, CPSR\n\t"
                    "bfi r0, lr, #5, #1\n\t"         /* set thumb bit */
@@ -1682,7 +1684,6 @@ __ASM_GLOBAL_FUNC( __wine_syscall_dispatcher,
 
                    "5:\tmovw r0, #0x000d\n\t" /* STATUS_INVALID_PARAMETER */
                    "movt r0, #0xc000\n\t"
-                   "add sp, sp, #0x10\n\t"
                    "b " __ASM_LOCAL_LABEL("__wine_syscall_dispatcher_return") "\n\t"
                    ".globl " __ASM_NAME("__wine_syscall_dispatcher_return") "\n"
                    __ASM_NAME("__wine_syscall_dispatcher_return") ":\n\t"
diff --git a/include/wine/asm.h b/include/wine/asm.h
index 0fa2dfcd1b7..908c7d7d19a 100644
--- a/include/wine/asm.h
+++ b/include/wine/asm.h
@@ -268,34 +268,19 @@
 # define __ASM_SYSCALL_FUNC(id,name,args) \
     __ASM_GLOBAL_FUNC( name, \
                        "push {r0-r3}\n\t" \
+                       ".seh_save_regs {r0-r3}\n\t" \
+                       ".seh_endprologue\n\t" \
                        "movw ip, #(" #id ")\n\t" \
                        "mov r3, lr\n\t" \
                        "bl " __ASM_NAME("__wine_syscall") "\n\t" \
+                       "add sp, #16\n\t" \
                        "bx lr" )
-# ifndef __PIC__
-#  define DEFINE_SYSCALL_HELPER32() \
+# define DEFINE_SYSCALL_HELPER32() \
     __ASM_GLOBAL_FUNC( __wine_syscall, \
                        "movw r0, :lower16:" __ASM_NAME("__wine_syscall_dispatcher") "\n\t" \
                        "movt r0, :upper16:" __ASM_NAME("__wine_syscall_dispatcher") "\n\t" \
                        "ldr r0, [r0]\n\t" \
                        "bx r0" )
-# elif defined __thumb__
-#  define DEFINE_SYSCALL_HELPER32() \
-    __ASM_GLOBAL_FUNC( __wine_syscall, \
-                       "ldr r0, 2f\n" \
-                       "1:\tadd r0, pc\n\t" \
-                       "ldr r0, [r0]\n\t" \
-                       "bx r0\n" \
-                       "2:\t.long " __ASM_NAME("__wine_syscall_dispatcher") "-1b-4" )
-# else
-#  define DEFINE_SYSCALL_HELPER32() \
-    __ASM_GLOBAL_FUNC( __wine_syscall, \
-                       "ldr r0, 2f\n" \
-                       "1:\tadd r0, pc\n\t" \
-                       "ldr r0, [r0]\n\t" \
-                       "bx r0\n" \
-                       "2:\t.long " __ASM_NAME("__wine_syscall_dispatcher") "-1b-8" )
-# endif
 #endif
 
 #endif  /* __WINE_WINE_ASM_H */