diff options
| author | H.J. Lu <hjl.tools@gmail.com> | 2017-12-19 02:43:50 -0800 |
|---|---|---|
| committer | H.J. Lu <hjl.tools@gmail.com> | 2017-12-19 02:44:04 -0800 |
| commit | f81ddabffd76ac9dd600b02adbf3e1dac4bb10ec (patch) | |
| tree | 7f9cac093b8e4d135be6ba830cd2bfe9a004131f /bits | |
| parent | 1a49fc59e42513247eaeac3feac6b099157eea7c (diff) | |
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.
Diffstat (limited to 'bits')
| -rw-r--r-- | bits/types/__cancel_jmp_buf_tag.h | 28 |
1 files changed, 28 insertions, 0 deletions
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 |