[PATCH 3/4] ntdll: Add CFI expressions for __wine_syscall_dispatcher.

[Rémi Bernon]

Making sure stack pointer points to previous syscall / exit frame before
entering a syscall, and restoring the PE frame information on return.

Wine-Bug: https://bugs.winehq.org/show_bug.cgi?id=52213
Signed-off-by: Rémi Bernon <rbernon at codeweavers.com>
---
 dlls/ntdll/unix/signal_i386.c   | 9 +++++++++
 dlls/ntdll/unix/signal_x86_64.c | 9 +++++++++
 2 files changed, 18 insertions(+)

diff --git a/dlls/ntdll/unix/signal_i386.c b/dlls/ntdll/unix/signal_i386.c
index d98a3b1d4bb..2f6e2fd4153 100644
--- a/dlls/ntdll/unix/signal_i386.c
+++ b/dlls/ntdll/unix/signal_i386.c
@@ -2492,6 +2492,9 @@ __ASM_GLOBAL_FUNC( __wine_syscall_dispatcher,
                    "movl %esi,0x30(%ecx)\n\t"
                    "movl %ebp,0x34(%ecx)\n\t"
                    "leal 0x34(%ecx),%ebp\n\t"
+                   __ASM_CFI(".cfi_def_cfa %ebp,0\n\t")
+                   __ASM_CFI(".cfi_rel_offset %eip,-0x2c\n\t")
+                   __ASM_CFI(".cfi_rel_offset %esp,-0x28\n\t")
                    "leal 4(%esp),%esi\n\t"         /* first argument */
                    "movl %eax,%ebx\n\t"
                    "shrl $8,%ebx\n\t"
@@ -2530,6 +2533,9 @@ __ASM_GLOBAL_FUNC( __wine_syscall_dispatcher,
                    "3:\tfnsave 0x40(%ecx)\n\t"
                    "fwait\n"
                    "4:\tmovl %ecx,%esp\n\t"
+                   __ASM_CFI(".cfi_def_cfa %ebp,0\n\t")
+                   __ASM_CFI(".cfi_rel_offset %eip,0x34c\n\t") /* frame->unwind_rip */
+                   __ASM_CFI(".cfi_rel_offset %esp,0x08\n\t")  /* frame->prev_frame */
                    "movl 0x1c(%esp),%edx\n\t"      /* frame->eax */
                    "andl $0xfff,%edx\n\t"          /* syscall number */
                    "cmpl 8(%ebx),%edx\n\t"         /* table->ServiceLimit */
@@ -2545,6 +2551,9 @@ __ASM_GLOBAL_FUNC( __wine_syscall_dispatcher,
                    "rep; movsl\n\t"
                    "call *(%eax,%edx,4)\n\t"
                    "leal -0x34(%ebp),%esp\n"
+                   __ASM_CFI(".cfi_def_cfa %ebp,0\n\t")
+                   __ASM_CFI(".cfi_rel_offset %eip,-0x2c\n\t")
+                   __ASM_CFI(".cfi_rel_offset %esp,-0x28\n\t")
                    "5:\tmovl 0(%esp),%ecx\n\t"     /* frame->syscall_flags + (frame->restore_flags << 16) */
                    "testl $0x68 << 16,%ecx\n\t"    /* CONTEXT_FLOATING_POINT | CONTEXT_EXTENDED_REGISTERS | CONTEXT_XSAVE */
                    "jz 3f\n\t"
diff --git a/dlls/ntdll/unix/signal_x86_64.c b/dlls/ntdll/unix/signal_x86_64.c
index f8cddd15569..ee2723cdb24 100644
--- a/dlls/ntdll/unix/signal_x86_64.c
+++ b/dlls/ntdll/unix/signal_x86_64.c
@@ -3166,6 +3166,9 @@ __ASM_GLOBAL_FUNC( __wine_syscall_dispatcher,
                    "movw %ss,0x90(%rcx)\n\t"
                    "movw %gs,0x92(%rcx)\n\t"
                    "movq %rbp,0x98(%rcx)\n\t"
+                   __ASM_CFI(".cfi_def_cfa %rcx,0\n\t")
+                   __ASM_CFI(".cfi_rel_offset %rip,0x70\n\t")
+                   __ASM_CFI(".cfi_rel_offset %rsp,0x88\n\t")
                    /* Legends of Runeterra hooks the first system call return instruction, and
                     * depends on us returning to it. Adjust the return address accordingly. */
                    "subq $0xb,0x70(%rcx)\n\t"
@@ -3206,6 +3209,9 @@ __ASM_GLOBAL_FUNC( __wine_syscall_dispatcher,
 #endif
                    "leaq 0x28(%rsp),%rsi\n\t"      /* first argument */
                    "movq %rcx,%rsp\n\t"
+                   __ASM_CFI(".cfi_def_cfa %rbp,0\n\t")
+                   __ASM_CFI(".cfi_rel_offset %rip,0x20\n\t") /* frame->unwind_rip */
+                   __ASM_CFI(".cfi_rel_offset %rsp,0x08\n\t") /* frame->prev_frame */
                    "movq 0x00(%rcx),%rax\n\t"
                    "movq 0x18(%rcx),%rdx\n\t"
                    "movl %eax,%ebx\n\t"
@@ -3231,6 +3237,9 @@ __ASM_GLOBAL_FUNC( __wine_syscall_dispatcher,
                    "movq (%rbx),%r10\n\t"          /* table->ServiceTable */
                    "callq *(%r10,%rax,8)\n\t"
                    "leaq -0x98(%rbp),%rcx\n"
+                   __ASM_CFI(".cfi_def_cfa %rcx,0\n\t")
+                   __ASM_CFI(".cfi_rel_offset %rip,0x70\n\t")
+                   __ASM_CFI(".cfi_rel_offset %rsp,0x88\n\t")
                    "2:\tmovl 0x94(%rcx),%edx\n\t"  /* frame->restore_flags */
 #ifdef __linux__
                    "testl $12,%r14d\n\t"           /* SYSCALL_HAVE_PTHREAD_TEB | SYSCALL_HAVE_WRFSGSBASE */
-- 
2.34.1