Add retguard to macppc kernel locore.S, ofwreal.S, setjmp.S

This changes RETGUARD_SETUP(ffs) to RETGUARD_SETUP(ffs, %r11, %r12)
and RETGUARD_CHECK(ffs) to RETGUARD_CHECK(ffs, %r11, %r12)
to show that r11 and r12 are in use between setup and check, and to
pick registers other than r11 and r12 in some kernel functions.

ok mortimer@ deraadt@

7 files changed, 24 insertions, 24 deletions

diff --git a/lib/libc/arch/powerpc/SYS.h b/lib/libc/arch/powerpc/SYS.h
index 8705241b48a..053728a6395 100644
--- a/lib/libc/arch/powerpc/SYS.h
+++ b/lib/libc/arch/powerpc/SYS.h
@@ -1,4 +1,4 @@
-/*	$OpenBSD: SYS.h,v 1.24 2020/10/26 22:07:05 gkoehler Exp $	*/
+/*	$OpenBSD: SYS.h,v 1.25 2020/11/28 19:49:30 gkoehler Exp $	*/
 /*-
  * Copyright (c) 1994
  *	Andrew Cagney.  All rights reserved.
@@ -84,15 +84,15 @@
 #define __END(x)		__END_HIDDEN(x); END(x)
 
 #define	PSEUDO_NOERROR(x,y)	SYSENTRY(x)				\
-				RETGUARD_SETUP(x);			\
+				RETGUARD_SETUP(x, %r11, %r12);		\
 				li	%r0, SYS_ ## y ;		\
 				sc;					\
-				RETGUARD_CHECK(x);			\
+				RETGUARD_CHECK(x, %r11, %r12);		\
 				blr;					\
 				__END(x)
 
 #define	PSEUDO_HIDDEN(x,y)	SYSENTRY_HIDDEN(x)			\
-				RETGUARD_SETUP(x);			\
+				RETGUARD_SETUP(x, %r11, %r12);		\
 				li	%r0, SYS_ ## y;			\
 				sc;					\
 				cmpwi	%r0, 0;				\
@@ -101,7 +101,7 @@
 				li	%r3, -1;			\
 				li	%r4, -1; /* for __syscall(lseek) */ \
 			.L_ret:						\
-				RETGUARD_CHECK(x);			\
+				RETGUARD_CHECK(x, %r11, %r12);		\
 				blr;					\
 				__END_HIDDEN(x)
 
diff --git a/lib/libc/arch/powerpc/string/ffs.S b/lib/libc/arch/powerpc/string/ffs.S
index c8a6eacc128..4d6410ebd49 100644
--- a/lib/libc/arch/powerpc/string/ffs.S
+++ b/lib/libc/arch/powerpc/string/ffs.S
@@ -1,4 +1,4 @@
-/*	$OpenBSD: ffs.S,v 1.2 2020/10/26 22:07:05 gkoehler Exp $ */
+/*	$OpenBSD: ffs.S,v 1.3 2020/11/28 19:49:30 gkoehler Exp $ */
 /*
  * Written by Christian Weisgerber <naddy@openbsd.org>.
  * Public domain.
@@ -7,12 +7,12 @@
 #include "SYS.h"
 
 ENTRY(ffs)
-	RETGUARD_SETUP(ffs)
+	RETGUARD_SETUP(ffs, %r11, %r12)
 	neg	%r4, %r3
 	and	%r3, %r3, %r4
 	cntlzw	%r3, %r3
 	subfic	%r3, %r3, 32
-	RETGUARD_CHECK(ffs)
+	RETGUARD_CHECK(ffs, %r11, %r12)
 	blr
 END(ffs)
 .protected
diff --git a/lib/libc/arch/powerpc/string/memmove.S b/lib/libc/arch/powerpc/string/memmove.S
index 4b6ba3cc82b..1aa29c3f544 100644
--- a/lib/libc/arch/powerpc/string/memmove.S
+++ b/lib/libc/arch/powerpc/string/memmove.S
@@ -1,4 +1,4 @@
-/* $OpenBSD: memmove.S,v 1.3 2020/10/26 22:07:05 gkoehler Exp $ */
+/* $OpenBSD: memmove.S,v 1.4 2020/11/28 19:49:30 gkoehler Exp $ */
 /* $NetBSD: memmove.S,v 1.3 2011/01/15 07:31:12 matt Exp $ */
 
 /* stropt/memmove.S, pl_string_common, pl_linux 10/11/04 11:45:37
@@ -46,7 +46,7 @@
 /* void *memcpy(void *to, const void *from, size_t len) */
 #if 0
 ENTRY(memcpy)
-	RETGUARD_SETUP(memmove)
+	RETGUARD_SETUP(memmove, %r11, %r12)
 	mr	%r8, %r3		/* Save dst (return value)	*/
 	b	fwd
 #endif
@@ -59,7 +59,7 @@ ENTRY(bcopy)
 
 /* void *memmove(void *, const void *, size_t) */
 ENTRY(memmove)
-	RETGUARD_SETUP(memmove)
+	RETGUARD_SETUP(memmove, %r11, %r12)
 	mr	%r8, %r3		/* Save dst (return value)	*/
 
 	cmpw	%r4, %r8		/* Branch to reverse if 	*/
@@ -169,7 +169,7 @@ rlast2:
 	bdnz+	rlast2		 	/* Dec ctr, and branch if more	*/
 					/* bytes left			*/
 done:
-	RETGUARD_CHECK(memmove)
+	RETGUARD_CHECK(memmove, %r11, %r12)
 	blr
 END_STRONG(memmove)
 END_WEAK(bcopy)
diff --git a/lib/libc/arch/powerpc/sys/sigpending.S b/lib/libc/arch/powerpc/sys/sigpending.S
index 0136633fef5..fa41751497e 100644
--- a/lib/libc/arch/powerpc/sys/sigpending.S
+++ b/lib/libc/arch/powerpc/sys/sigpending.S
@@ -1,4 +1,4 @@
-/* $OpenBSD: sigpending.S,v 1.7 2020/10/26 22:07:05 gkoehler Exp $ */
+/* $OpenBSD: sigpending.S,v 1.8 2020/11/28 19:49:30 gkoehler Exp $ */
 /*
  * Copyright (c) 2012 Mark Kettenis
  *
@@ -21,12 +21,12 @@
 
 	.text
 SYSENTRY(sigpending)
-	RETGUARD_SETUP(sigpending)
+	RETGUARD_SETUP(sigpending, %r11, %r12)
 	mr	%r5, %r3
 	li	%r0, SYS_sigpending
 	sc
 	stw	%r3, 0(%r5)
 	li	%r3, 0
-	RETGUARD_CHECK(sigpending)
+	RETGUARD_CHECK(sigpending, %r11, %r12)
 	blr
 SYSCALL_END(sigpending)
diff --git a/lib/libc/arch/powerpc/sys/sigprocmask.S b/lib/libc/arch/powerpc/sys/sigprocmask.S
index 57b0987b542..bb21c0ca741 100644
--- a/lib/libc/arch/powerpc/sys/sigprocmask.S
+++ b/lib/libc/arch/powerpc/sys/sigprocmask.S
@@ -1,4 +1,4 @@
-/* $OpenBSD: sigprocmask.S,v 1.13 2020/10/26 22:07:06 gkoehler Exp $ */
+/* $OpenBSD: sigprocmask.S,v 1.14 2020/11/28 19:49:30 gkoehler Exp $ */
 
 /*
  * Copyright (c) 1996 Dale Rahn
@@ -31,7 +31,7 @@
 
 	.text
 SYSENTRY_HIDDEN(sigprocmask)
-	RETGUARD_SETUP(sigprocmask)
+	RETGUARD_SETUP(sigprocmask, %r11, %r12)
 	stwu	1, -16(1)
 	stw	5, 12(1)
 	
@@ -64,6 +64,6 @@ SYSENTRY_HIDDEN(sigprocmask)
 	li	3, 0
 	addi	1, 1, 16
 .L_end:
-	RETGUARD_CHECK(sigprocmask)
+	RETGUARD_CHECK(sigprocmask, %r11, %r12)
 	blr
 SYSCALL_END_HIDDEN(sigprocmask)
diff --git a/lib/libc/arch/powerpc/sys/sigsuspend.S b/lib/libc/arch/powerpc/sys/sigsuspend.S
index 822345dd448..1c0f2372fff 100644
--- a/lib/libc/arch/powerpc/sys/sigsuspend.S
+++ b/lib/libc/arch/powerpc/sys/sigsuspend.S
@@ -1,4 +1,4 @@
-/* $OpenBSD: sigsuspend.S,v 1.6 2020/10/26 22:07:06 gkoehler Exp $ */
+/* $OpenBSD: sigsuspend.S,v 1.7 2020/11/28 19:49:30 gkoehler Exp $ */
 
 /*
  * Copyright (c) 1996 Dale Rahn
@@ -31,7 +31,7 @@
 
 	.text
 SYSENTRY_HIDDEN(sigsuspend)
-	RETGUARD_SETUP(sigsuspend)
+	RETGUARD_SETUP(sigsuspend, %r11, %r12)
 	li	%r0, SYS_sigsuspend
 
 	lwz	%r3, 0(%r3)		/* load the mask */
@@ -42,6 +42,6 @@ SYSENTRY_HIDDEN(sigsuspend)
 	stw	%r0, R2_OFFSET_ERRNO(2)
 	li	%r3, -1
 .L_ret:
-	RETGUARD_CHECK(sigsuspend)
+	RETGUARD_CHECK(sigsuspend, %r11, %r12)
 	blr
 SYSCALL_END_HIDDEN(sigsuspend)
diff --git a/lib/libc/arch/powerpc/sys/tfork_thread.S b/lib/libc/arch/powerpc/sys/tfork_thread.S
index b33ef21c937..a90bd4ec390 100644
--- a/lib/libc/arch/powerpc/sys/tfork_thread.S
+++ b/lib/libc/arch/powerpc/sys/tfork_thread.S
@@ -1,4 +1,4 @@
-/*	$OpenBSD: tfork_thread.S,v 1.9 2020/10/26 22:07:06 gkoehler Exp $	*/
+/*	$OpenBSD: tfork_thread.S,v 1.10 2020/11/28 19:49:30 gkoehler Exp $	*/
 
 /*
  * Copyright (c) 2005 Tim Wiess <tim@nop.cx>
@@ -19,7 +19,7 @@
 #include "SYS.h"
 
 ENTRY(__tfork_thread)
-	RETGUARD_SETUP(__tfork_thread)
+	RETGUARD_SETUP(__tfork_thread, %r11, %r12)
 	/* call __tfork */
 	li	%r0, SYS___tfork
 	sc
@@ -45,6 +45,6 @@ ENTRY(__tfork_thread)
 	stw	0, R2_OFFSET_ERRNO(%r2)
 	li	%r3, -1
 9:
-	RETGUARD_CHECK(__tfork_thread)
+	RETGUARD_CHECK(__tfork_thread, %r11, %r12)
 	blr
 END(__tfork_thread)