From 1e3a2e82aaea009f14b9e808e56f06cd7f3f9f15 Mon Sep 17 00:00:00 2001
From: Brooks Davis <brooks@FreeBSD.org>
Date: Thu, 21 Jan 2016 17:29:01 +0000
Subject: [PATCH] Fix the implementations of PSEUDO_NOERROR and PSEUDO.

The PSEUDO* macros should not declare <syscall>, only _<syscall> and
__sys_<syscall>.  This was causing the interposing C wrappers to be
ignored due to link order.

Reviewed by:	kib
Obtained from:	CheriBSD (4e8e13c90fc6a80e1520de44a6864cfd78b3b56d)
MFC after:	1 week
Sponsored by:	DARPA, AFRL
Differential Revision:	https://reviews.freebsd.org/D4097
---
 lib/libc/mips/SYS.h | 44 +++++++++++++++++++++++++++++---------------
 1 file changed, 29 insertions(+), 15 deletions(-)

diff --git a/lib/libc/mips/SYS.h b/lib/libc/mips/SYS.h
index 10205b8793a..ceb68121b07 100644
--- a/lib/libc/mips/SYS.h
+++ b/lib/libc/mips/SYS.h
@@ -100,19 +100,6 @@
  * Do a syscall that cannot fail (sync, get{p,u,g,eu,eg)id)
  */
 #define RSYSCALL_NOERROR(x)						\
-	PSEUDO_NOERROR(x)
-
-/*
- * Do a normal syscall.
- */
-#define RSYSCALL(x)							\
-	PSEUDO(x)
-
-/*
- * Do a renamed or pseudo syscall (e.g., _exit()), where the entrypoint
- * and syscall name are not the same.
- */
-#define PSEUDO_NOERROR(x)						\
 LEAF(__sys_ ## x);							\
 	.weak _C_LABEL(x);						\
 	_C_LABEL(x) = _C_LABEL(__CONCAT(__sys_,x));			\
@@ -120,9 +107,12 @@ LEAF(__sys_ ## x);							\
 	_C_LABEL(__CONCAT(_,x)) = _C_LABEL(__CONCAT(__sys_,x));		\
 	SYSTRAP(x);							\
 	j ra;								\
-	END(__sys_ ## x)
+END(__sys_ ## x)
 
-#define PSEUDO(x)							\
+/*
+ * Do a normal syscall.
+ */
+#define RSYSCALL(x)							\
 LEAF(__sys_ ## x);							\
 	.weak _C_LABEL(x);						\
 	_C_LABEL(x) = _C_LABEL(__CONCAT(__sys_,x));			\
@@ -135,3 +125,27 @@ LEAF(__sys_ ## x);							\
 err:									\
 	PIC_TAILCALL(__cerror);						\
 END(__sys_ ## x)
+
+/*
+ * Do a renamed or pseudo syscall (e.g., _exit()), where the entrypoint
+ * and syscall name are not the same.
+ */
+#define PSEUDO_NOERROR(x)						\
+LEAF(__sys_ ## x);							\
+	.weak _C_LABEL(__CONCAT(_,x));					\
+	_C_LABEL(__CONCAT(_,x)) = _C_LABEL(__CONCAT(__sys_,x));		\
+	SYSTRAP(x);							\
+	j ra;								\
+END(__sys_ ## x)
+
+#define PSEUDO(x)							\
+LEAF(__sys_ ## x);							\
+	.weak _C_LABEL(__CONCAT(_,x));					\
+	_C_LABEL(__CONCAT(_,x)) = _C_LABEL(__CONCAT(__sys_,x));		\
+	PIC_PROLOGUE(__sys_ ## x);					\
+	SYSTRAP(x);							\
+	bne a3,zero,err;						\
+	PIC_RETURN();							\
+err:									\
+	PIC_TAILCALL(__cerror);						\
+END(__sys_ ## x)