[01/23] x86: Add feature_1 to tcbhead_t [BZ #22563]
Commit Message
This will be used by CET run-time control.
[BZ #22563]
* nptl/pthread_create.c (__pthread_create_2_1): Use
THREAD_COPY_ADDITONAL_INFO to copy additonal info if defined.
* sysdeps/i386/nptl/tcb-offsets.sym (FEATURE_1_OFFSET): New.
* sysdeps/i386/nptl/tls.h (tcbhead_t): Add feature_1.
* sysdeps/unix/sysv/linux/x86/pthreaddef.h: New file.
* sysdeps/x86_64/nptl/tcb-offsets.sym (FEATURE_1_OFFSET): New.
* sysdeps/x86_64/nptl/tls.h (tcbhead_t): Rename __glibc_unused1
to feature_1.
---
nptl/pthread_create.c | 5 +++++
sysdeps/i386/nptl/tcb-offsets.sym | 1 +
sysdeps/i386/nptl/tls.h | 4 ++++
sysdeps/unix/sysv/linux/x86/pthreaddef.h | 24 ++++++++++++++++++++++++
sysdeps/x86_64/nptl/tcb-offsets.sym | 1 +
sysdeps/x86_64/nptl/tls.h | 5 ++++-
6 files changed, 39 insertions(+), 1 deletion(-)
create mode 100644 sysdeps/unix/sysv/linux/x86/pthreaddef.h
Comments
On 05/08/2018 10:39 PM, H.J. Lu wrote:
> diff --git a/sysdeps/i386/nptl/tls.h b/sysdeps/i386/nptl/tls.h
> index 8ca0924692..c3a0edd253 100644
> --- a/sysdeps/i386/nptl/tls.h
> +++ b/sysdeps/i386/nptl/tls.h
> @@ -50,6 +50,10 @@ typedef struct
> void *__private_tm[4];
> /* GCC split stack support. */
> void *__private_ss;
> + /* Bit 0: IBT.
> + Bit 1: SHSTK.
> + */
> + unsigned int feature_1;
> } tcbhead_t;
It might be nicer to reuse __glibc_reserved1 for that (I think
__ASSUME_PRIVATE_FUTEX is always defined these days), in case some
extern tools hard-code the tcbhead_t layout.
Thanks,
Florian
@@ -712,6 +712,11 @@ __pthread_create_2_1 (pthread_t *newthread, const pthread_attr_t *attr,
THREAD_COPY_POINTER_GUARD (pd);
#endif
+ /* Copy additonal info. */
+#ifdef THREAD_COPY_ADDITONAL_INFO
+ THREAD_COPY_ADDITONAL_INFO (pd);
+#endif
+
/* Verify the sysinfo bits were copied in allocate_stack if needed. */
#ifdef NEED_DL_SYSINFO
CHECK_THREAD_SYSINFO (pd);
@@ -15,3 +15,4 @@ POINTER_GUARD offsetof (tcbhead_t, pointer_guard)
#ifndef __ASSUME_PRIVATE_FUTEX
PRIVATE_FUTEX offsetof (tcbhead_t, private_futex)
#endif
+FEATURE_1_OFFSET offsetof (tcbhead_t, feature_1)
@@ -50,6 +50,10 @@ typedef struct
void *__private_tm[4];
/* GCC split stack support. */
void *__private_ss;
+ /* Bit 0: IBT.
+ Bit 1: SHSTK.
+ */
+ unsigned int feature_1;
} tcbhead_t;
# define TLS_MULTIPLE_THREADS_IN_TCB 1
new file mode 100644
@@ -0,0 +1,24 @@
+/* Pthread macros. Linux/x86 version.
+ Copyright (C) 2018 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>
+
+/* Wee need to copy feature_1 in pthread_create. */
+#define THREAD_COPY_ADDITONAL_INFO(descr) \
+ ((descr)->header.feature_1 \
+ = THREAD_GETMEM (THREAD_SELF, header.feature_1))
@@ -15,6 +15,7 @@ VGETCPU_CACHE_OFFSET offsetof (tcbhead_t, vgetcpu_cache)
#ifndef __ASSUME_PRIVATE_FUTEX
PRIVATE_FUTEX offsetof (tcbhead_t, private_futex)
#endif
+FEATURE_1_OFFSET offsetof (tcbhead_t, feature_1)
-- Not strictly offsets, but these values are also used in the TCB.
TCB_CANCELSTATE_BITMASK CANCELSTATE_BITMASK
@@ -56,7 +56,10 @@ typedef struct
# else
int __glibc_reserved1;
# endif
- int __glibc_unused1;
+ /* Bit 0: IBT.
+ Bit 1: SHSTK.
+ */
+ unsigned int feature_1;
/* Reservation of some values for the TM ABI. */
void *__private_tm[4];
/* GCC split stack support. */