Kernel: Fix signal trampoline

32 bit did not even support it and 64 bit did not align stack
2024-04-18 13:32:40 +03:00
parent a698f91db4
commit 061012a268
4 changed files with 18 additions and 6 deletions
--- a/kernel/arch/i686/Signal.S
+++ b/kernel/arch/i686/Signal.S
@@ -7,22 +7,26 @@

 .global signal_trampoline
 signal_trampoline:
-	ud2
-
 	pushl %ebp
 	movl %esp, %ebp
-	subl $8, %esp

 	pusha

 	movl 40(%esp), %edi
 	movl 36(%esp), %eax

+	// align stack to 16 bytes
+	movl %esp, %ebx
+	andl $0x0F, %ebx
+	subl %ebx, %esp
+
 	subl $12, %esp
 	pushl %edi
 	call *%eax
 	addl $16, %esp

+	// restore stack
+	addl %ebx, %esp
 	popa

 	leave
--- a/kernel/arch/x86_64/Signal.S
+++ b/kernel/arch/x86_64/Signal.S
@@ -23,12 +23,18 @@ signal_trampoline:
 	pushq %r14
 	pushq %r15

-	// This is 16 byte aligned
-
 	movq 128(%rsp), %rdi
 	movq 120(%rsp), %rax
+
+	// align stack to 16 bytes
+	movq %rsp, %rbx
+	andq $0x0F, %rbx
+	subq %rbx, %rsp
+
 	call *%rax

+	// restore stack
+	addq %rbx, %rsp
 	popq %r15
 	popq %r14
 	popq %r13