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[PATCH] Maintain stack alignment in ____longjmp_chk on x86_64


2011-04-07  Andreas Schwab  <schwab@redhat.com>

	* sysdeps/unix/sysv/linux/x86_64/____longjmp_chk.S (CALL_FAIL):
	Maintain aligned stack.
	(CHECK_RSP): Remove unused macro.
---
 sysdeps/unix/sysv/linux/x86_64/____longjmp_chk.S |   26 ++++++++++++---------
 1 files changed, 15 insertions(+), 11 deletions(-)

diff --git a/sysdeps/unix/sysv/linux/x86_64/____longjmp_chk.S b/sysdeps/unix/sysv/linux/x86_64/____longjmp_chk.S
index da35115..3881082 100644
--- a/sysdeps/unix/sysv/linux/x86_64/____longjmp_chk.S
+++ b/sysdeps/unix/sysv/linux/x86_64/____longjmp_chk.S
@@ -1,4 +1,4 @@
-/* Copyright (C) 2001,2004,2005,2006,2009,2010 Free Software Foundation, Inc.
+/* Copyright (C) 2001,2004,2005,2006,2009,2010,2011 Free Software Foundation, Inc.
    This file is part of the GNU C Library.
 
    The GNU C Library is free software; you can redistribute it and/or
@@ -30,19 +30,23 @@ longjmp_msg:
 //#define __longjmp ____longjmp_chk
 
 #ifdef PIC
-# define CALL_FAIL	leaq	longjmp_msg(%rip), %rdi;		      \
-			call	__GI___fortify_fail
+# define CALL_FAIL	subq	$8, %rsp;				      \
+			cfi_remember_state;				      \
+			cfi_def_cfa_offset(16);				      \
+			leaq	longjmp_msg(%rip), %rdi;		      \
+			call	__GI___fortify_fail;			      \
+			nop;						      \
+			cfi_restore_state
 #else
-# define CALL_FAIL	movq	$longjmp_msg, %rdi;			      \
-			call	__fortify_fail
+# define CALL_FAIL	subq	$8, %rsp;				      \
+			cfi_remember_state;				      \
+			cfi_def_cfa_offset(16);				      \
+			movq	$longjmp_msg, %rdi;			      \
+			call	__fortify_fail;				      \
+			nop;						      \
+			cfi_restore_state
 #endif
 
-#define CHECK_RSP(reg) \
-	cmpq	reg, %rsp;						      \
-	jbe	.Lok;							      \
-	CALL_FAIL;							      \
-.Lok:
-
 /* Jump to the position specified by ENV, causing the
    setjmp call there to return VAL, or 1 if VAL is 0.
    void __longjmp (__jmp_buf env, int val).  */
-- 
1.7.4.2


-- 
Andreas Schwab, schwab@redhat.com
GPG Key fingerprint = D4E8 DBE3 3813 BB5D FA84  5EC7 45C6 250E 6F00 984E
"And now for something completely different."


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