From f81ddabffd76ac9dd600b02adbf3e1dac4bb10ec Mon Sep 17 00:00:00 2001 From: "H.J. Lu" Date: Tue, 19 Dec 2017 02:43:50 -0800 Subject: 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 . (__pthread_unwind_buf_t): Use struct __cancel_jmp_buf_tag with __cancel_jmp_buf. * sysdeps/unix/sysv/linux/hppa/pthread.h: Likewise. --- sysdeps/nptl/pthread.h | 7 ++----- 1 file changed, 2 insertions(+), 5 deletions(-) (limited to 'sysdeps/nptl') diff --git a/sysdeps/nptl/pthread.h b/sysdeps/nptl/pthread.h index 2b2b386..787ac6e 100644 --- a/sysdeps/nptl/pthread.h +++ b/sysdeps/nptl/pthread.h @@ -27,6 +27,7 @@ #include #include #include +#include /* 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__)); -- cgit v1.1