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 /sysdeps/nptl | |
| 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 'sysdeps/nptl')
| -rw-r--r-- | sysdeps/nptl/pthread.h | 7 |
1 files changed, 2 insertions, 5 deletions
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__)); |