From: Andreas Schwab <schwab@redhat.com>
To: libc-hacker@sourceware.org
Subject: [PATCH] Maintain stack alignment in ____longjmp_chk on x86_64
Date: Thu, 07 Apr 2011 12:30:00 -0000 [thread overview]
Message-ID: <m3oc4ib5x5.fsf@redhat.com> (raw)
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."
next reply other threads:[~2011-04-07 12:30 UTC|newest]
Thread overview: 3+ messages / expand[flat|nested] mbox.gz Atom feed top
2011-04-07 12:30 Andreas Schwab [this message]
2011-04-07 13:29 ` Ulrich Drepper
2011-04-07 13:39 ` Andreas Schwab
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=m3oc4ib5x5.fsf@redhat.com \
--to=schwab@redhat.com \
--cc=libc-hacker@sourceware.org \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for read-only IMAP folder(s) and NNTP newsgroup(s).