This is the mail archive of the
libc-alpha@sourceware.org
mailing list for the glibc project.
Re: [PATCH 1/2] Linux/x86: Update cancel_jmp_buf to match __jmp_buf_tag [BZ #22563]
On Mon, Dec 18, 2017 at 9:37 AM, Joseph Myers <joseph@codesourcery.com> wrote:
> I think any change applied to sysdeps/nptl/pthread.h should also be
> applied to sysdeps/unix/sysv/linux/hppa/pthread.h to avoid divergence
> between those header versions.
>
Here is the updated patch with sysdeps/unix/sysv/linux/hppa/pthread.h change.
Tested natively on i386, x86_64 and x32. Tested hppa-linux-gnu with
build-many-glibcs.py.
I am checking it in tomorrow.
--
H.J.
From 2fc9116c385b43e69628dfcbfa7d9f7f8c32a03d Mon Sep 17 00:00:00 2001
From: "H.J. Lu" <hjl.tools@gmail.com>
Date: Wed, 6 Dec 2017 15:00:46 -0800
Subject: [PATCH] Linux/x86: Update cancel_jmp_buf to match __jmp_buf_tag [BZ
#22563]
On x86, padding in struct __jmp_buf_tag is used for shadow stack pointer
to support shadow stack in Intel Control-flow Enforcemen Technology.
Since the cancel_jmp_buf array is passed to setjmp and longjmp by
casting it to pointer to struct __jmp_buf_tag, it should be as large
as struct __jmp_buf_tag. Otherwise when shadow stack is enabled,
setjmp and longjmp will write and read beyond cancel_jmp_buf when saving
and restoring shadow stack pointer.
This patch adds bits/types/__cancel_jmp_buf_tag.h to define struct
__cancel_jmp_buf_tag so that Linux/x86 can add saved_mask to
cancel_jmp_buf.
Tested natively on i386, x86_64 and x32. Tested hppa-linux-gnu with
build-many-glibcs.py.
[BZ #22563]
* bits/types/__cancel_jmp_buf_tag.h: New file.
* sysdeps/unix/sysv/linux/x86/bits/types/__cancel_jmp_buf_tag.h
* sysdeps/unix/sysv/linux/x86/pthreaddef.h: Likewise.
* sysdeps/unix/sysv/linux/x86/nptl/pthreadP.h: Likewise.
* nptl/Makefile (headers): Add
bits/types/__cancel_jmp_buf_tag.h.
* nptl/descr.h [NEED_SAVED_MASK_IN_CANCEL_JMP_BUF]
(pthread_unwind_buf): Add saved_mask to cancel_jmp_buf.
* sysdeps/nptl/pthread.h: Include
<bits/types/__cancel_jmp_buf_tag.h>.
(__pthread_unwind_buf_t): Use struct __cancel_jmp_buf_tag with
__cancel_jmp_buf.
* sysdeps/unix/sysv/linux/hppa/pthread.h: Likewise.
---
bits/types/__cancel_jmp_buf_tag.h | 28 +++++++++++++++++
nptl/Makefile | 3 +-
nptl/descr.h | 3 ++
sysdeps/nptl/pthread.h | 7 ++---
sysdeps/unix/sysv/linux/hppa/pthread.h | 7 ++---
.../linux/x86/bits/types/__cancel_jmp_buf_tag.h | 31 +++++++++++++++++++
sysdeps/unix/sysv/linux/x86/nptl/pthreadP.h | 36 ++++++++++++++++++++++
sysdeps/unix/sysv/linux/x86/pthreaddef.h | 22 +++++++++++++
8 files changed, 126 insertions(+), 11 deletions(-)
create mode 100644 bits/types/__cancel_jmp_buf_tag.h
create mode 100644 sysdeps/unix/sysv/linux/x86/bits/types/__cancel_jmp_buf_tag.h
create mode 100644 sysdeps/unix/sysv/linux/x86/nptl/pthreadP.h
create mode 100644 sysdeps/unix/sysv/linux/x86/pthreaddef.h
diff --git a/bits/types/__cancel_jmp_buf_tag.h b/bits/types/__cancel_jmp_buf_tag.h
new file mode 100644
index 0000000000..c843f44239
--- /dev/null
+++ b/bits/types/__cancel_jmp_buf_tag.h
@@ -0,0 +1,28 @@
+/* Define struct __cancel_jmp_buf_tag.
+ Copyright (C) 2017 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
+ modify it under the terms of the GNU Lesser General Public
+ License as published by the Free Software Foundation; either
+ version 2.1 of the License, or (at your option) any later version.
+
+ The GNU C Library is distributed in the hope that it will be useful,
+ but WITHOUT ANY WARRANTY; without even the implied warranty of
+ MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+ Lesser General Public License for more details.
+
+ You should have received a copy of the GNU Lesser General Public
+ License along with the GNU C Library; if not, see
+ <http://www.gnu.org/licenses/>. */
+
+#ifndef ____cancel_jmp_buf_tag_defined
+#define ____cancel_jmp_buf_tag_defined 1
+
+struct __cancel_jmp_buf_tag
+ {
+ __jmp_buf __cancel_jmp_buf;
+ int __mask_was_saved;
+ };
+
+#endif
diff --git a/nptl/Makefile b/nptl/Makefile
index 570a42301c..60d036a1ea 100644
--- a/nptl/Makefile
+++ b/nptl/Makefile
@@ -22,7 +22,8 @@ subdir := nptl
include ../Makeconfig
-headers := pthread.h semaphore.h bits/semaphore.h
+headers := pthread.h semaphore.h bits/semaphore.h \
+ bits/types/__cancel_jmp_buf_tag.h
extra-libs := libpthread
extra-libs-others := $(extra-libs)
diff --git a/nptl/descr.h b/nptl/descr.h
index c83b17b674..fdeb397eab 100644
--- a/nptl/descr.h
+++ b/nptl/descr.h
@@ -65,6 +65,9 @@ struct pthread_unwind_buf
{
__jmp_buf jmp_buf;
int mask_was_saved;
+#ifdef NEED_SAVED_MASK_IN_CANCEL_JMP_BUF
+ __sigset_t saved_mask;
+#endif
} cancel_jmp_buf[1];
union
diff --git a/sysdeps/nptl/pthread.h b/sysdeps/nptl/pthread.h
index 2b2b386ab3..787ac6e4cd 100644
--- a/sysdeps/nptl/pthread.h
+++ b/sysdeps/nptl/pthread.h
@@ -27,6 +27,7 @@
#include <bits/setjmp.h>
#include <bits/wordsize.h>
#include <bits/types/struct_timespec.h>
+#include <bits/types/__cancel_jmp_buf_tag.h>
/* Detach state. */
@@ -523,11 +524,7 @@ extern void pthread_testcancel (void);
typedef struct
{
- struct
- {
- __jmp_buf __cancel_jmp_buf;
- int __mask_was_saved;
- } __cancel_jmp_buf[1];
+ struct __cancel_jmp_buf_tag __cancel_jmp_buf[1];
void *__pad[4];
} __pthread_unwind_buf_t __attribute__ ((__aligned__));
diff --git a/sysdeps/unix/sysv/linux/hppa/pthread.h b/sysdeps/unix/sysv/linux/hppa/pthread.h
index d1973741cd..3d69ddcd00 100644
--- a/sysdeps/unix/sysv/linux/hppa/pthread.h
+++ b/sysdeps/unix/sysv/linux/hppa/pthread.h
@@ -27,6 +27,7 @@
#include <bits/setjmp.h>
#include <bits/wordsize.h>
#include <bits/types/struct_timespec.h>
+#include <bits/types/__cancel_jmp_buf_tag.h>
/* Detach state. */
@@ -499,11 +500,7 @@ extern void pthread_testcancel (void);
typedef struct
{
- struct
- {
- __jmp_buf __cancel_jmp_buf;
- int __mask_was_saved;
- } __cancel_jmp_buf[1];
+ struct __cancel_jmp_buf_tag __cancel_jmp_buf[1];
void *__pad[4];
} __pthread_unwind_buf_t __attribute__ ((__aligned__));
diff --git a/sysdeps/unix/sysv/linux/x86/bits/types/__cancel_jmp_buf_tag.h b/sysdeps/unix/sysv/linux/x86/bits/types/__cancel_jmp_buf_tag.h
new file mode 100644
index 0000000000..830a6ec90c
--- /dev/null
+++ b/sysdeps/unix/sysv/linux/x86/bits/types/__cancel_jmp_buf_tag.h
@@ -0,0 +1,31 @@
+/* Define struct __cancel_jmp_buf_tag.
+ Copyright (C) 2017 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
+ modify it under the terms of the GNU Lesser General Public
+ License as published by the Free Software Foundation; either
+ version 2.1 of the License, or (at your option) any later version.
+
+ The GNU C Library is distributed in the hope that it will be useful,
+ but WITHOUT ANY WARRANTY; without even the implied warranty of
+ MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+ Lesser General Public License for more details.
+
+ You should have received a copy of the GNU Lesser General Public
+ License along with the GNU C Library; if not, see
+ <http://www.gnu.org/licenses/>. */
+
+#ifndef ____cancel_jmp_buf_tag_defined
+#define ____cancel_jmp_buf_tag_defined 1
+
+#include <bits/types/__sigset_t.h>
+
+struct __cancel_jmp_buf_tag
+ {
+ __jmp_buf __cancel_jmp_buf;
+ int __mask_was_saved;
+ __sigset_t __saved_mask;
+ };
+
+#endif
diff --git a/sysdeps/unix/sysv/linux/x86/nptl/pthreadP.h b/sysdeps/unix/sysv/linux/x86/nptl/pthreadP.h
new file mode 100644
index 0000000000..8c36ba3a5d
--- /dev/null
+++ b/sysdeps/unix/sysv/linux/x86/nptl/pthreadP.h
@@ -0,0 +1,36 @@
+/* Internal pthread header. Linux/x86 version.
+ Copyright (C) 2017 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
+ modify it under the terms of the GNU Lesser General Public
+ License as published by the Free Software Foundation; either
+ version 2.1 of the License, or (at your option) any later version.
+
+ The GNU C Library is distributed in the hope that it will be useful,
+ but WITHOUT ANY WARRANTY; without even the implied warranty of
+ MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+ Lesser General Public License for more details.
+
+ You should have received a copy of the GNU Lesser General Public
+ License along with the GNU C Library; if not, see
+ <http://www.gnu.org/licenses/>. */
+
+#include_next <nptl/pthreadP.h>
+
+#ifndef _PTHREADP_H_X86
+#define _PTHREADP_H_X86 1
+
+extern struct pthread_unwind_buf ____pthread_unwind_buf_private;
+
+_Static_assert (sizeof (____pthread_unwind_buf_private.cancel_jmp_buf)
+ >= sizeof (struct __jmp_buf_tag),
+ "size of cancel_jmp_buf < sizeof __jmp_buf_tag");
+
+extern __pthread_unwind_buf_t ____pthread_unwind_buf;
+
+_Static_assert (sizeof (____pthread_unwind_buf.__cancel_jmp_buf)
+ >= sizeof (struct __jmp_buf_tag),
+ "size of __cancel_jmp_buf < sizeof __jmp_buf_tag");
+
+#endif
diff --git a/sysdeps/unix/sysv/linux/x86/pthreaddef.h b/sysdeps/unix/sysv/linux/x86/pthreaddef.h
new file mode 100644
index 0000000000..89d19d60a1
--- /dev/null
+++ b/sysdeps/unix/sysv/linux/x86/pthreaddef.h
@@ -0,0 +1,22 @@
+/* Pthread macros. Linux/x86 version.
+ Copyright (C) 2017 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
+ modify it under the terms of the GNU Lesser General Public
+ License as published by the Free Software Foundation; either
+ version 2.1 of the License, or (at your option) any later version.
+
+ The GNU C Library is distributed in the hope that it will be useful,
+ but WITHOUT ANY WARRANTY; without even the implied warranty of
+ MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+ Lesser General Public License for more details.
+
+ You should have received a copy of the GNU Lesser General Public
+ License along with the GNU C Library; if not, see
+ <http://www.gnu.org/licenses/>. */
+
+#include_next <pthreaddef.h>
+
+/* Need saved_mask in cancel_jmp_buf. */
+#define NEED_SAVED_MASK_IN_CANCEL_JMP_BUF 1
--
2.14.3