Add retguard macros for arm64 asm and apply them in the straightforward

cases in kernel and libc.
ok deraadt@

10 files changed, 30 insertions, 10 deletions

diff --git a/lib/libc/arch/aarch64/gen/byte_swap_2.S b/lib/libc/arch/aarch64/gen/byte_swap_2.S
index 5bd951ee8a4..76b7db58c5c 100644
--- a/lib/libc/arch/aarch64/gen/byte_swap_2.S
+++ b/lib/libc/arch/aarch64/gen/byte_swap_2.S
@@ -1,4 +1,4 @@
-/*	$OpenBSD: byte_swap_2.S,v 1.1 2017/01/11 18:09:24 patrick Exp $	*/
+/*	$OpenBSD: byte_swap_2.S,v 1.2 2018/08/12 17:15:10 mortimer Exp $	*/
 /*	$NetBSD: byte_swap_2.S,v 1.3 2003/04/05 23:08:51 bjh21 Exp $	*/
 
 /*-
@@ -36,7 +36,9 @@ _ENTRY(_C_LABEL(__bswap16))
 _ENTRY(_C_LABEL(ntohs))
 _ENTRY(_C_LABEL(htons))
 _PROF_PROLOGUE
+	RETGUARD_SETUP(__bswap16, x15)
 	and     w8, w0, #0xffff
         ubfx    w0, w0, #8, #8
 	bfi     w0, w8, #8, #16
+	RETGUARD_CHECK(__bswap16, x15)
 	ret
diff --git a/lib/libc/arch/aarch64/gen/byte_swap_4.S b/lib/libc/arch/aarch64/gen/byte_swap_4.S
index 6d9119b2230..dfc3db40d29 100644
--- a/lib/libc/arch/aarch64/gen/byte_swap_4.S
+++ b/lib/libc/arch/aarch64/gen/byte_swap_4.S
@@ -1,4 +1,4 @@
-/*	$OpenBSD: byte_swap_4.S,v 1.1 2017/01/11 18:09:24 patrick Exp $	*/
+/*	$OpenBSD: byte_swap_4.S,v 1.2 2018/08/12 17:15:10 mortimer Exp $	*/
 /*	$NetBSD: byte_swap_4.S,v 1.2 2003/04/05 23:08:51 bjh21 Exp $	*/
 
 /*-
@@ -36,5 +36,7 @@ _ENTRY(_C_LABEL(__bswap32))
 _ENTRY(_C_LABEL(ntohl))
 _ENTRY(_C_LABEL(htonl))
 _PROF_PROLOGUE
+	RETGUARD_SETUP(__bswap32, x15)
 	rev	w0, w0
+	RETGUARD_CHECK(__bswap32, x15)
 	ret
diff --git a/lib/libc/arch/aarch64/sys/Ovfork.S b/lib/libc/arch/aarch64/sys/Ovfork.S
index 3dd82683ac7..db40fb8b118 100644
--- a/lib/libc/arch/aarch64/sys/Ovfork.S
+++ b/lib/libc/arch/aarch64/sys/Ovfork.S
@@ -1,4 +1,4 @@
-/*	$OpenBSD: Ovfork.S,v 1.3 2017/11/22 20:36:02 kettenis Exp $	*/
+/*	$OpenBSD: Ovfork.S,v 1.4 2018/08/12 17:15:10 mortimer Exp $	*/
 /*	$NetBSD: Ovfork.S,v 1.6 2003/08/07 16:42:03 agc Exp $	*/
 
 /*-
@@ -35,9 +35,11 @@
 #include "SYS.h"
 
 SYSENTRY_HIDDEN(vfork)
+	RETGUARD_SETUP(vfork, x15)
 	mov	x2, x30
 	SYSTRAP(vfork)
 	bcs	CERROR
 	mov	x30, x2
+	RETGUARD_CHECK(vfork, x15)
 	ret
 SYSCALL_END_HIDDEN(vfork)
diff --git a/lib/libc/arch/aarch64/sys/brk.S b/lib/libc/arch/aarch64/sys/brk.S
index af0e31de410..574c615afb9 100644
--- a/lib/libc/arch/aarch64/sys/brk.S
+++ b/lib/libc/arch/aarch64/sys/brk.S
@@ -1,4 +1,4 @@
-/*	$OpenBSD: brk.S,v 1.4 2017/11/22 20:36:02 kettenis Exp $	*/
+/*	$OpenBSD: brk.S,v 1.5 2018/08/12 17:15:10 mortimer Exp $	*/
 /*	$NetBSD: brk.S,v 1.7 2003/12/26 11:23:44 martin Exp $	*/
 
 /*-
@@ -48,6 +48,7 @@ __minbrk:
  * Change the data segment size
  */
 ENTRY(brk)
+	RETGUARD_SETUP(brk, x15)
 #ifdef __PIC__
 	/* Setup the GOT */
 	adrp	x3, :got:__minbrk
@@ -81,6 +82,7 @@ ENTRY(brk)
 
 	/* Return 0 for success */
 	mov	x0, #0x00000000
+	RETGUARD_CHECK(brk, x15)
 	ret
 
 	.align	3
diff --git a/lib/libc/arch/aarch64/sys/cerror.S b/lib/libc/arch/aarch64/sys/cerror.S
index 4ef8359f63f..e12dcf44062 100644
--- a/lib/libc/arch/aarch64/sys/cerror.S
+++ b/lib/libc/arch/aarch64/sys/cerror.S
@@ -1,4 +1,4 @@
-/*	$OpenBSD: cerror.S,v 1.4 2017/03/19 00:29:02 guenther Exp $	*/
+/*	$OpenBSD: cerror.S,v 1.5 2018/08/12 17:15:10 mortimer Exp $	*/
 /*-
  * Copyright (c) 2014 Andrew Turner
  * All rights reserved.
@@ -32,8 +32,10 @@
 #define TCB_OFFSET_ERRNO	(-12)
 
 _ENTRY(CERROR)
+	RETGUARD_SETUP(CERROR, x15)
 	mrs	x1, tpidr_el0
 	str	w0, [x1, #TCB_OFFSET_ERRNO]
 	movn	x0, #0
+	RETGUARD_CHECK(CERROR, x15)
 	ret
 END(CERROR)
diff --git a/lib/libc/arch/aarch64/sys/sbrk.S b/lib/libc/arch/aarch64/sys/sbrk.S
index 75b25a73c57..1e3bd836832 100644
--- a/lib/libc/arch/aarch64/sys/sbrk.S
+++ b/lib/libc/arch/aarch64/sys/sbrk.S
@@ -1,4 +1,4 @@
-/*	$OpenBSD: sbrk.S,v 1.3 2017/11/22 20:36:02 kettenis Exp $	*/
+/*	$OpenBSD: sbrk.S,v 1.4 2018/08/12 17:15:10 mortimer Exp $	*/
 /*	$NetBSD: sbrk.S,v 1.7 2003/08/07 16:42:05 agc Exp $	*/
 
 /*-
@@ -49,6 +49,7 @@ __curbrk:
  * Change the data segment size
  */
 ENTRY(sbrk)
+	RETGUARD_SETUP(sbrk, x15)
 #ifdef __PIC__
 	/* Setup the GOT */
 	adrp	x3, :got:__curbrk
@@ -71,6 +72,7 @@ ENTRY(sbrk)
 	str	x1, [x2]
 
 	/* Return old curbrk value */
+	RETGUARD_CHECK(sbrk, x15)
 	ret
 
 	.align	3
diff --git a/lib/libc/arch/aarch64/sys/sigpending.S b/lib/libc/arch/aarch64/sys/sigpending.S
index 076473b1ccb..c532274f79c 100644
--- a/lib/libc/arch/aarch64/sys/sigpending.S
+++ b/lib/libc/arch/aarch64/sys/sigpending.S
@@ -1,4 +1,4 @@
-/*	$OpenBSD: sigpending.S,v 1.2 2017/02/23 22:50:07 patrick Exp $	*/
+/*	$OpenBSD: sigpending.S,v 1.3 2018/08/12 17:15:10 mortimer Exp $	*/
 /*	$NetBSD: sigpending.S,v 1.5 2003/08/07 16:42:05 agc Exp $	*/
 
 /*-
@@ -35,10 +35,12 @@
 #include "SYS.h"
 
 SYSENTRY(sigpending)
+	RETGUARD_SETUP(sigpending, x15)
 	mov	x2, x0
 	SYSTRAP(sigpending)
 	bcs	CERROR
 	str	w0, [x2]
 	mov	x0, #0
+	RETGUARD_CHECK(sigpending, x15)
 	ret
 SYSCALL_END(sigpending)
diff --git a/lib/libc/arch/aarch64/sys/sigprocmask.S b/lib/libc/arch/aarch64/sys/sigprocmask.S
index 7a9ea688f14..a07ef23ae9f 100644
--- a/lib/libc/arch/aarch64/sys/sigprocmask.S
+++ b/lib/libc/arch/aarch64/sys/sigprocmask.S
@@ -1,4 +1,4 @@
-/*	$OpenBSD: sigprocmask.S,v 1.2 2017/02/22 22:18:51 patrick Exp $	*/
+/*	$OpenBSD: sigprocmask.S,v 1.3 2018/08/12 17:15:10 mortimer Exp $	*/
 /*	$NetBSD: sigprocmask.S,v 1.5 2003/08/07 16:42:05 agc Exp $	*/
 
 /*-
@@ -35,6 +35,7 @@
 #include "SYS.h"
 
 SYSENTRY_HIDDEN(sigprocmask)
+	RETGUARD_SETUP(sigprocmask, x15)
 	cbz	x1, 1f
 	ldr	w1, [x1]
 	b	2f
@@ -49,5 +50,6 @@ SYSENTRY_HIDDEN(sigprocmask)
 	str	w0, [x2]
 1:
 	mov	x0, #0x00000000
+	RETGUARD_CHECK(sigprocmask, x15)
 	ret
 SYSCALL_END_HIDDEN(sigprocmask)
diff --git a/lib/libc/arch/aarch64/sys/sigsuspend.S b/lib/libc/arch/aarch64/sys/sigsuspend.S
index 9be04da1525..d28d0377af6 100644
--- a/lib/libc/arch/aarch64/sys/sigsuspend.S
+++ b/lib/libc/arch/aarch64/sys/sigsuspend.S
@@ -1,4 +1,4 @@
-/*	$OpenBSD: sigsuspend.S,v 1.1 2017/01/11 18:09:24 patrick Exp $	*/
+/*	$OpenBSD: sigsuspend.S,v 1.2 2018/08/12 17:15:10 mortimer Exp $	*/
 /*	$NetBSD: sigsuspend.S,v 1.6 2003/08/07 16:42:05 agc Exp $	*/
 
 /*-
@@ -35,9 +35,11 @@
 #include "SYS.h"
 
 SYSENTRY_HIDDEN(sigsuspend)
+	RETGUARD_SETUP(sigsuspend, x15)
 	ldr	w0, [x0]
 	SYSTRAP(sigsuspend)
 	bcs	CERROR
 	mov	x0, #0
+	RETGUARD_CHECK(sigsuspend, x15)
 	ret
 SYSCALL_END_HIDDEN(sigsuspend)
diff --git a/lib/libc/arch/aarch64/sys/tfork_thread.S b/lib/libc/arch/aarch64/sys/tfork_thread.S
index 5dda781adc2..6e515c32b24 100644
--- a/lib/libc/arch/aarch64/sys/tfork_thread.S
+++ b/lib/libc/arch/aarch64/sys/tfork_thread.S
@@ -1,4 +1,4 @@
-/* $OpenBSD: tfork_thread.S,v 1.2 2017/02/20 08:42:46 patrick Exp $ */
+/* $OpenBSD: tfork_thread.S,v 1.3 2018/08/12 17:15:10 mortimer Exp $ */
 /*
  * Copyright (c) 2005 Dale Rahn <drahn@openbsd.org>
  *
@@ -24,11 +24,13 @@
  */
 
 ENTRY(__tfork_thread)
+	RETGUARD_SETUP(__tfork_thread, x15)
 	SYSTRAP(__tfork)
 	bcs	CERROR
 
 	/* check if we are parent or child */
 	cbz	x0, 1f
+	RETGUARD_CHECK(__tfork_thread, x15)
 	ret
 
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