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. --- nptl/Makefile | 3 ++- nptl/descr.h | 3 +++ 2 files changed, 5 insertions(+), 1 deletion(-) (limited to 'nptl') 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 -- cgit 1.4.1