Add retguard macros for libkern

ok deraadt

15 files changed, 43 insertions, 12 deletions

diff --git a/sys/lib/libkern/arch/amd64/bcmp.S b/sys/lib/libkern/arch/amd64/bcmp.S
index 4cb1b3d6894..96754ed68a4 100644
--- a/sys/lib/libkern/arch/amd64/bcmp.S
+++ b/sys/lib/libkern/arch/amd64/bcmp.S
@@ -1,6 +1,7 @@
 #include <machine/asm.h>
 
 ENTRY(bcmp)
+	RETGUARD_SETUP(bcmp, r11)
 	xorl	%eax,%eax		/* clear return value */
 
 	movq	%rdx,%rcx		/* compare by words */
@@ -16,4 +17,5 @@ ENTRY(bcmp)
 	je	L2
 
 L1:	incl	%eax
-L2:	ret
+L2:	RETGUARD_CHECK(bcmp, r11)
+	ret
diff --git a/sys/lib/libkern/arch/amd64/bzero.S b/sys/lib/libkern/arch/amd64/bzero.S
index 354e2066ed3..a1c9a94d955 100644
--- a/sys/lib/libkern/arch/amd64/bzero.S
+++ b/sys/lib/libkern/arch/amd64/bzero.S
@@ -7,6 +7,7 @@
 #include <machine/asm.h>
 
 ENTRY(bzero)
+	RETGUARD_SETUP(bzero, r11)
 	movq	%rsi,%rdx
 
 	xorq	%rax,%rax		/* set fill data to 0 */
@@ -35,5 +36,5 @@ ENTRY(bzero)
 L1:	movq	%rdx,%rcx		/* zero remainder by bytes */
 	rep
 	stosb
-
+	RETGUARD_CHECK(bzero, r11)
 	ret
diff --git a/sys/lib/libkern/arch/amd64/ffs.S b/sys/lib/libkern/arch/amd64/ffs.S
index 1beb25861b2..4acb74c4132 100644
--- a/sys/lib/libkern/arch/amd64/ffs.S
+++ b/sys/lib/libkern/arch/amd64/ffs.S
@@ -7,11 +7,13 @@
 #include <machine/asm.h>
 
 ENTRY(ffs)
+	RETGUARD_SETUP(ffs, r11)
 	bsfl	%edi,%eax
 	jz	L1	 		/* ZF is set if all bits are 0 */
 	incl	%eax			/* bits numbered from 1, not 0 */
-	ret
+	jmp L2
 
 	_ALIGN_TEXT
 L1:	xorl	%eax,%eax		/* clear result */
+L2:	RETGUARD_CHECK(ffs, r11)
 	ret
diff --git a/sys/lib/libkern/arch/amd64/htonl.S b/sys/lib/libkern/arch/amd64/htonl.S
index b9b121597f6..f7d640521d1 100644
--- a/sys/lib/libkern/arch/amd64/htonl.S
+++ b/sys/lib/libkern/arch/amd64/htonl.S
@@ -44,6 +44,8 @@ _ENTRY(_C_LABEL(htonl))
 _ENTRY(_C_LABEL(ntohl))
 _ENTRY(_C_LABEL(bswap32))
 _PROF_PROLOGUE
+	RETGUARD_SETUP(htonl, r11)
 	movl	%edi,%eax
 	bswap	%eax
+	RETGUARD_CHECK(htonl, r11)
 	ret
diff --git a/sys/lib/libkern/arch/amd64/htons.S b/sys/lib/libkern/arch/amd64/htons.S
index a35b67b2951..15016f5736e 100644
--- a/sys/lib/libkern/arch/amd64/htons.S
+++ b/sys/lib/libkern/arch/amd64/htons.S
@@ -44,6 +44,8 @@ _ENTRY(_C_LABEL(htons))
 _ENTRY(_C_LABEL(ntohs))
 _ENTRY(_C_LABEL(bswap16))
 _PROF_PROLOGUE
+	RETGUARD_SETUP(htons, r11)
 	movl	%edi,%eax
 	xchgb	%ah,%al
+	RETGUARD_CHECK(htons, r11)
 	ret
diff --git a/sys/lib/libkern/arch/amd64/memchr.S b/sys/lib/libkern/arch/amd64/memchr.S
index 1738e17f8ee..1ec17272f1b 100644
--- a/sys/lib/libkern/arch/amd64/memchr.S
+++ b/sys/lib/libkern/arch/amd64/memchr.S
@@ -7,6 +7,7 @@
 #include <machine/asm.h>
 
 ENTRY(memchr)
+	RETGUARD_SETUP(memchr, r11)
 	movb	%sil,%al		/* set character to search for */
 	movq	%rdx,%rcx		/* set length of search */
 	testq	%rcx,%rcx		/* test for len == 0 */
@@ -15,6 +16,7 @@ ENTRY(memchr)
 	scasb
 	jne	L1			/* scan failed, return null */
 	leaq	-1(%rdi),%rax		/* adjust result of scan */
-	ret
+	jmp L2
 L1:	xorq	%rax,%rax
+L2:	RETGUARD_CHECK(memchr, r11)
 	ret
diff --git a/sys/lib/libkern/arch/amd64/memcmp.S b/sys/lib/libkern/arch/amd64/memcmp.S
index 0d97f6a9bd2..b53e2d1c21a 100644
--- a/sys/lib/libkern/arch/amd64/memcmp.S
+++ b/sys/lib/libkern/arch/amd64/memcmp.S
@@ -7,6 +7,7 @@
 #include <machine/asm.h>
 
 ENTRY(memcmp)
+	RETGUARD_SETUP(memcmp, r11)
 	movq	%rdx,%rcx		/* compare by longs */
 	shrq	$3,%rcx
 	repe
@@ -20,7 +21,7 @@ ENTRY(memcmp)
 	jne	L6			/* do we match? */
 
 	xorl	%eax,%eax		/* we match, return zero	*/
-	ret
+	jmp L7
 
 L5:	movl	$8,%ecx			/* We know that one of the next	*/
 	subq	%rcx,%rdi		/* eight pairs of bytes do not	*/
@@ -32,4 +33,5 @@ L6:	xorl	%eax,%eax		/* Perform unsigned comparison	*/
 	xorl	%edx,%edx
 	movb	-1(%rsi),%dl
 	subl    %edx,%eax
+L7:	RETGUARD_CHECK(memcmp, r11)
 	ret
diff --git a/sys/lib/libkern/arch/amd64/memmove.S b/sys/lib/libkern/arch/amd64/memmove.S
index 351e4d53a49..3a0bed88790 100644
--- a/sys/lib/libkern/arch/amd64/memmove.S
+++ b/sys/lib/libkern/arch/amd64/memmove.S
@@ -45,6 +45,7 @@ ENTRY(bcopy)
 	/* fall into memmove */
 
 ENTRY(memmove)
+	RETGUARD_SETUP(memmove, r10)
 	movq	%rdi,%r11	/* save dest */
 	movq	%rdx,%rcx
 	movq	%rdi,%rax
@@ -54,6 +55,7 @@ ENTRY(memmove)
 	jmp	2f		/* nope */
 
 ENTRY(memcpy)
+	RETGUARD_SETUP(memmove, r10)
 	movq	%rdi,%r11	/* save dest */
 	movq	%rdx,%rcx
 2:
@@ -65,7 +67,7 @@ ENTRY(memcpy)
 	rep
 	movsb
 	movq	%r11,%rax
-	ret
+	jmp 3f
 1:
 	addq	%rcx,%rdi	/* copy backwards. */
 	addq	%rcx,%rsi
@@ -83,4 +85,5 @@ ENTRY(memcpy)
 	movsq
 	movq	%r11,%rax
 	cld
+3:	RETGUARD_CHECK(memmove, r10)
 	ret
diff --git a/sys/lib/libkern/arch/amd64/memset.S b/sys/lib/libkern/arch/amd64/memset.S
index 67d6404e932..1ccdfe79a9d 100644
--- a/sys/lib/libkern/arch/amd64/memset.S
+++ b/sys/lib/libkern/arch/amd64/memset.S
@@ -7,6 +7,7 @@
 #include <machine/asm.h>
 
 ENTRY(memset)
+	RETGUARD_SETUP(memset, r10)
 	movq	%rsi,%rax
 	andq	$0xff,%rax
 	movq	%rdx,%rcx
@@ -49,5 +50,5 @@ ENTRY(memset)
 L1:	rep
 	stosb
 	movq	%r11,%rax
-
+	RETGUARD_CHECK(memset, r10)
 	ret
diff --git a/sys/lib/libkern/arch/amd64/scanc.S b/sys/lib/libkern/arch/amd64/scanc.S
index 4ecaae3c15b..2ae94d96d74 100644
--- a/sys/lib/libkern/arch/amd64/scanc.S
+++ b/sys/lib/libkern/arch/amd64/scanc.S
@@ -36,6 +36,7 @@
 #include <machine/asm.h>
 
 ENTRY(scanc)
+	RETGUARD_SETUP(scanc, r10)
 	movq	%rdx,%r11
 	movb	%cl,%dl
 	movl	%edi,%ecx
@@ -51,4 +52,5 @@ ENTRY(scanc)
 	jnz	1b
 2:
 	movl	%ecx,%eax
+	RETGUARD_CHECK(scanc, r10)
 	ret
diff --git a/sys/lib/libkern/arch/amd64/skpc.S b/sys/lib/libkern/arch/amd64/skpc.S
index 5942a1c07e8..c67f9c3b252 100644
--- a/sys/lib/libkern/arch/amd64/skpc.S
+++ b/sys/lib/libkern/arch/amd64/skpc.S
@@ -36,6 +36,7 @@
 #include <machine/asm.h>
 
 ENTRY(skpc)
+	RETGUARD_SETUP(skpc, r10)
 	movl	%edi,%eax
 	movq	%rsi,%rcx
 	movq	%rdx,%rdi
@@ -45,4 +46,5 @@ ENTRY(skpc)
 	incq	%rcx
 1:
 	movl	%ecx,%eax
+	RETGUARD_CHECK(skpc, r10)
 	ret
diff --git a/sys/lib/libkern/arch/amd64/strchr.S b/sys/lib/libkern/arch/amd64/strchr.S
index f78e030486e..a4234184b47 100644
--- a/sys/lib/libkern/arch/amd64/strchr.S
+++ b/sys/lib/libkern/arch/amd64/strchr.S
@@ -1,4 +1,4 @@
-/*	$OpenBSD: strchr.S,v 1.3 2014/12/09 15:13:57 reyk Exp $	*/
+/*	$OpenBSD: strchr.S,v 1.4 2018/07/03 23:22:48 mortimer Exp $	*/
 /*	$NetBSD: strchr.S,v 1.7 2014/03/22 19:16:34 jakllsch Exp $	*/
 
 /*-
@@ -44,6 +44,8 @@ STRONG_ALIAS(index, strchr)
  */
 
 ENTRY(strchr)
+	RETGUARD_SETUP(strchr, r9)
+	RETGUARD_PUSH(r9)
 	movabsq	$0x0101010101010101,%r8
 
 	movzbq	%sil,%rdx	/* value to search for (c) */
@@ -85,7 +87,7 @@ ENTRY(strchr)
 	bsf	%r11,%r11	/* 7, 15, 23 ... 63 */
 8:	shr	$3,%r11		/* 0, 1, 2 .. 7 */
 	lea	-8(%r11,%rdi),%rax
-	ret
+	jmp 12f
 
 /* End of string, check whether char is before NUL */
 	_ALIGN_TEXT		/* adds three byte nop */
@@ -97,6 +99,8 @@ ENTRY(strchr)
 	cmp	%r11,%rax
 	jae	8b		/* return 'found' if same - searching for NUL */
 11:	xor	%eax,%eax	/* char not found */
+12:	RETGUARD_POP(r9)
+	RETGUARD_CHECK(strchr, r9)
 	ret
 
 /* Source misaligned: read aligned word and make low bytes invalid */
diff --git a/sys/lib/libkern/arch/amd64/strcmp.S b/sys/lib/libkern/arch/amd64/strcmp.S
index 7f1656ee80a..3ba13a49c34 100644
--- a/sys/lib/libkern/arch/amd64/strcmp.S
+++ b/sys/lib/libkern/arch/amd64/strcmp.S
@@ -1,4 +1,4 @@
-/*	$OpenBSD: strcmp.S,v 1.3 2014/12/09 15:13:57 reyk Exp $	*/
+/*	$OpenBSD: strcmp.S,v 1.4 2018/07/03 23:22:48 mortimer Exp $	*/
 /*	$NetBSD: strcmp.S,v 1.2 2014/03/22 19:16:34 jakllsch Exp $	*/
 
 /*
@@ -9,6 +9,7 @@
 #include <machine/asm.h>
 
 ENTRY(strcmp)
+	RETGUARD_SETUP(strcmp, r10)
 	/*
 	 * Align s1 to word boundary.
 	 * Consider unrolling loop?
@@ -68,4 +69,5 @@ ENTRY(strcmp)
 	movzbq	%al,%rax
 	movzbq	%dl,%rdx
 	subq	%rdx,%rax
+	RETGUARD_CHECK(strcmp, r10)
 	ret
diff --git a/sys/lib/libkern/arch/amd64/strlen.S b/sys/lib/libkern/arch/amd64/strlen.S
index 1528ad3eb67..888f2c05d12 100644
--- a/sys/lib/libkern/arch/amd64/strlen.S
+++ b/sys/lib/libkern/arch/amd64/strlen.S
@@ -1,4 +1,4 @@
-/*	$OpenBSD: strlen.S,v 1.5 2016/03/20 16:50:30 krw Exp $	*/
+/*	$OpenBSD: strlen.S,v 1.6 2018/07/03 23:22:48 mortimer Exp $	*/
 /*	$NetBSD: strlen.S,v 1.6 2014/03/22 19:16:34 jakllsch Exp $	*/
 
 /*-
@@ -112,6 +112,7 @@
  */
 
 ENTRY(strlen)
+	RETGUARD_SETUP(strlen, r10)
 	movabsq	$0x0101010101010101,%r8
 
 	test	$7,%dil
@@ -139,6 +140,7 @@ ENTRY(strlen)
 	bsf	%rdx,%rdx		/* 7, 15, 23 ... 63 */
 	shr	$3,%rdx			/* 0, 1, 2 ... 7 */
 	lea	-8(%rax,%rdx),%rax
+	RETGUARD_CHECK(strlen, r10)
 	ret
 
 /* Misaligned, read aligned word and make low bytes non-zero */
diff --git a/sys/lib/libkern/arch/amd64/strrchr.S b/sys/lib/libkern/arch/amd64/strrchr.S
index 50561cba786..945146d0059 100644
--- a/sys/lib/libkern/arch/amd64/strrchr.S
+++ b/sys/lib/libkern/arch/amd64/strrchr.S
@@ -1,4 +1,4 @@
-/*	$OpenBSD: strrchr.S,v 1.3 2014/12/09 15:13:57 reyk Exp $	*/
+/*	$OpenBSD: strrchr.S,v 1.4 2018/07/03 23:22:48 mortimer Exp $	*/
 /*	$NetBSD: strrchr.S,v 1.3 2014/03/22 19:16:34 jakllsch Exp $	*/
 
 /*
@@ -11,6 +11,7 @@
 STRONG_ALIAS(rindex, strrchr)
 
 ENTRY(strrchr)
+	RETGUARD_SETUP(strrchr, r10)
 	movzbq	%sil,%rcx
 
 	/* zero return value */
@@ -120,4 +121,5 @@ ENTRY(strrchr)
 	jne	.Lloop
 
 .Ldone:
+	RETGUARD_CHECK(strrchr, r10)
 	ret