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GNU C Library master sources branch hjl/pr22743/master created. glibc-2.26.9000-1169-gd139cd3
- From: hjl at sourceware dot org
- To: glibc-cvs at sourceware dot org
- Date: 26 Jan 2018 16:06:00 -0000
- Subject: GNU C Library master sources branch hjl/pr22743/master created. glibc-2.26.9000-1169-gd139cd3
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http://sourceware.org/git/gitweb.cgi?p=glibc.git;a=commitdiff;h=d139cd31adaf9f091a36027c8a452b016a05e95c
commit d139cd31adaf9f091a36027c8a452b016a05e95c
Author: H.J. Lu <hjl.tools@gmail.com>
Date: Wed Jan 24 15:27:49 2018 -0800
nptl: Update struct pthread_unwind_buf [BZ #22743]
In glibc 2.28, the size of cancel_jmp_buf in struct pthread_unwind_buf
has been increased to match the size of __jmp_buf_tag on Linux/x86 in
order to save and restore shadow stack register. pthread_unwind_buf is
used in <pthread.h>, whose address is passed from applications to
libpthread. To access the private data in struct pthread_unwind_buf,
which is placed after cancel_jmp_buf, in libpthread, we must know which
struct pthread_unwind_buf, before glibc 28 and after glibc 2.28, is used
in caller. If the size of caller's struct pthread_unwind_buf is smaller
than what libpthread expects, libpthread will override caller's stack
since struct pthread_unwind_buf is placed on caller's stack.
We enable shadow stack at run-time only if program and all used shared
objects, including dlopened ones, are shadow stack enabled, which means
that they must be compiled with GCC 8 or above and glibc 2.28 or above.
Since we need to save and restore shadow stack register only if shadow
stack is enabled, we can safely assume that caller is compiled with
smaller struct pthread_unwind_buf on stack if shadow stack isn't enabled
at run-time. For callers with larger struct pthread_unwind_buf, but
shadow stack isn't enabled, we just have some unused space on caller's
stack.
struct pthread_unwind_buf is changed to union of
1. struct cancel_jmp_buf[1], which contains the common fields of struct
full and struct compat_pthread_unwind_buf.
2. struct full_pthread_unwind_buf, which is the full layout of the
cleanup buffer.
3. struct compat_pthread_unwind_buf, which is the compatible layout of
the cleanup buffer.
A macro, UNWIND_BUF_PRIV, is added to get the pointer to the priv field.
By default, it uses the priv field of struct compat_pthread_unwind_buf.
If a target defines NEED_SAVED_MASK_IN_CANCEL_JMP_BUF, it must provide
its own version of UNEIND_BUF_PRIV to get the pointer to the priv field.
On Linux/x86, it uses the priv field of struct compat_pthread_unwind_buf
if shadow stack is disabled and struct full_pthread_unwind_buf if shadow
stack is enabled.
Note: There is an unused pointer space in pthread_unwind_buf_data. But
it isn't unsuitable for saving and restoring shadow stack register since
x32 is a 64-bit process with 32-bit software pointer and kernel may
place x32 shadow stack above 4GB. We need to save and restore 64-bit
shadow stack register for x32.
[BZ #22743]
* csu/libc-start.c (LIBC_START_MAIN): Use the full version of
the cleanup buffer.
* nptl/cleanup.c (__pthread_register_cancel): Use UNWIND_BUF_PRIV
to access the priv field in the cleanup buffer.
(__pthread_unregister_cancel): Likewise.
* nptl/cleanup_defer.c (__pthread_register_cancel_defer):
Likewise.
(__pthread_unregister_cancel_restore): Likewise.
* nptl/unwind.c (unwind_stop): Likewise.
(__pthread_unwind_next): Likewise.
* nptl/descr.h (pthread_unwind_buf_data): New.
(full_pthread_unwind_buf): Likewise.
(compat_pthread_unwind_buf): Likewise.
(pthread_unwind_buf): Updated to use full_pthread_unwind_buf
and compat_pthread_unwind_buf.
(UNWIND_BUF_PRIV): New. Macro to get pointer to the priv field
in the cleanup buffer.
* nptl/pthread_create.c (START_THREAD_DEFN): Use the full
version of the cleanup buffer.
(__pthread_create_2_1): Use THREAD_COPY_ADDITONAL_INFO to copy
additonal info if defined.
* sysdeps/unix/sysv/linux/x86/nptl/pthreadP.h: Use the full
version of the cleanup buffer to check cancel_jmp_buf size.
* sysdeps/unix/sysv/linux/x86/pthreaddef.h
(THREAD_COPY_ADDITONAL_INFO): New.
(UNWIND_BUF_PRIV): Likewise.
diff --git a/csu/libc-start.c b/csu/libc-start.c
index 605222f..c6bbc97 100644
--- a/csu/libc-start.c
+++ b/csu/libc-start.c
@@ -298,8 +298,10 @@ LIBC_START_MAIN (int (*main) (int, char **, char ** MAIN_AUXVEC_DECL),
struct pthread *self = THREAD_SELF;
/* Store old info. */
- unwind_buf.priv.data.prev = THREAD_GETMEM (self, cleanup_jmp_buf);
- unwind_buf.priv.data.cleanup = THREAD_GETMEM (self, cleanup);
+ unwind_buf.full.priv.data.prev
+ = THREAD_GETMEM (self, cleanup_jmp_buf);
+ unwind_buf.full.priv.data.cleanup
+ = THREAD_GETMEM (self, cleanup);
/* Store the new cleanup handler info. */
THREAD_SETMEM (self, cleanup_jmp_buf, &unwind_buf);
diff --git a/nptl/cleanup.c b/nptl/cleanup.c
index d21b86e..6403a42 100644
--- a/nptl/cleanup.c
+++ b/nptl/cleanup.c
@@ -28,8 +28,9 @@ __pthread_register_cancel (__pthread_unwind_buf_t *buf)
struct pthread *self = THREAD_SELF;
/* Store old info. */
- ibuf->priv.data.prev = THREAD_GETMEM (self, cleanup_jmp_buf);
- ibuf->priv.data.cleanup = THREAD_GETMEM (self, cleanup);
+ union pthread_unwind_buf_data *priv = UNWIND_BUF_PRIV (self, ibuf);
+ priv->data.prev = THREAD_GETMEM (self, cleanup_jmp_buf);
+ priv->data.cleanup = THREAD_GETMEM (self, cleanup);
/* Store the new cleanup handler info. */
THREAD_SETMEM (self, cleanup_jmp_buf, (struct pthread_unwind_buf *) buf);
@@ -42,7 +43,9 @@ __cleanup_fct_attribute
__pthread_unregister_cancel (__pthread_unwind_buf_t *buf)
{
struct pthread_unwind_buf *ibuf = (struct pthread_unwind_buf *) buf;
+ struct pthread *self = THREAD_SELF;
- THREAD_SETMEM (THREAD_SELF, cleanup_jmp_buf, ibuf->priv.data.prev);
+ THREAD_SETMEM (self, cleanup_jmp_buf,
+ UNWIND_BUF_PRIV (self, ibuf)->data.prev);
}
hidden_def (__pthread_unregister_cancel)
diff --git a/nptl/cleanup_defer.c b/nptl/cleanup_defer.c
index 5701ce4..fddf743 100644
--- a/nptl/cleanup_defer.c
+++ b/nptl/cleanup_defer.c
@@ -28,8 +28,9 @@ __pthread_register_cancel_defer (__pthread_unwind_buf_t *buf)
struct pthread *self = THREAD_SELF;
/* Store old info. */
- ibuf->priv.data.prev = THREAD_GETMEM (self, cleanup_jmp_buf);
- ibuf->priv.data.cleanup = THREAD_GETMEM (self, cleanup);
+ union pthread_unwind_buf_data *priv = UNWIND_BUF_PRIV (self, ibuf);
+ priv->data.prev = THREAD_GETMEM (self, cleanup_jmp_buf);
+ priv->data.cleanup = THREAD_GETMEM (self, cleanup);
int cancelhandling = THREAD_GETMEM (self, cancelhandling);
@@ -49,9 +50,9 @@ __pthread_register_cancel_defer (__pthread_unwind_buf_t *buf)
cancelhandling = curval;
}
- ibuf->priv.data.canceltype = (cancelhandling & CANCELTYPE_BITMASK
- ? PTHREAD_CANCEL_ASYNCHRONOUS
- : PTHREAD_CANCEL_DEFERRED);
+ priv->data.canceltype = (cancelhandling & CANCELTYPE_BITMASK
+ ? PTHREAD_CANCEL_ASYNCHRONOUS
+ : PTHREAD_CANCEL_DEFERRED);
/* Store the new cleanup handler info. */
THREAD_SETMEM (self, cleanup_jmp_buf, (struct pthread_unwind_buf *) buf);
@@ -64,11 +65,12 @@ __pthread_unregister_cancel_restore (__pthread_unwind_buf_t *buf)
{
struct pthread *self = THREAD_SELF;
struct pthread_unwind_buf *ibuf = (struct pthread_unwind_buf *) buf;
+ union pthread_unwind_buf_data *priv = UNWIND_BUF_PRIV (self, ibuf);
- THREAD_SETMEM (self, cleanup_jmp_buf, ibuf->priv.data.prev);
+ THREAD_SETMEM (self, cleanup_jmp_buf, priv->data.prev);
int cancelhandling;
- if (ibuf->priv.data.canceltype != PTHREAD_CANCEL_DEFERRED
+ if (priv->data.canceltype != PTHREAD_CANCEL_DEFERRED
&& ((cancelhandling = THREAD_GETMEM (self, cancelhandling))
& CANCELTYPE_BITMASK) == 0)
{
diff --git a/nptl/descr.h b/nptl/descr.h
index 1cc6b09..662696d 100644
--- a/nptl/descr.h
+++ b/nptl/descr.h
@@ -55,11 +55,30 @@
/ PTHREAD_KEY_2NDLEVEL_SIZE)
+/* Private data in the cleanup buffer. */
+union pthread_unwind_buf_data
+{
+ /* This is the placeholder of the public version. */
+ void *pad[4];
+ struct
+ {
+ /* Pointer to the previous cleanup buffer. */
+ struct pthread_unwind_buf *prev;
-/* Internal version of the buffer to store cancellation handler
+ /* Backward compatibility: state of the old-style cleanup
+ handler at the time of the previous new-style cleanup handler
+ installment. */
+ struct _pthread_cleanup_buffer *cleanup;
+
+ /* Cancellation type before the push call. */
+ int canceltype;
+ } data;
+};
+
+/* Internal full version of the buffer to store cancellation handler
information. */
-struct pthread_unwind_buf
+struct full_pthread_unwind_buf
{
struct
{
@@ -70,27 +89,49 @@ struct pthread_unwind_buf
#endif
} cancel_jmp_buf[1];
- union
+ union pthread_unwind_buf_data priv;
+};
+
+/* Internal compatible version of the buffer to store cancellation
+ handler information. */
+struct compat_pthread_unwind_buf
+{
+ struct
{
- /* This is the placeholder of the public version. */
- void *pad[4];
+ __jmp_buf jmp_buf;
+ int mask_was_saved;
+ } cancel_jmp_buf[1];
+
+ union pthread_unwind_buf_data priv;
+};
+/* Internal version of the buffer to store cancellation handler
+ information. */
+struct pthread_unwind_buf
+{
+ union
+ {
+ /* The common fields of full and compatible versions. */
struct
{
- /* Pointer to the previous cleanup buffer. */
- struct pthread_unwind_buf *prev;
-
- /* Backward compatibility: state of the old-style cleanup
- handler at the time of the previous new-style cleanup handler
- installment. */
- struct _pthread_cleanup_buffer *cleanup;
-
- /* Cancellation type before the push call. */
- int canceltype;
- } data;
- } priv;
+ __jmp_buf jmp_buf;
+ int mask_was_saved;
+ } cancel_jmp_buf[1];
+ struct full_pthread_unwind_buf full;
+ struct compat_pthread_unwind_buf compat;
+ };
};
+/* Get pointer to the priv field from THREAD_SELF, "self", and pointer
+ to the cleanup buffer, "p". By default, the compatible version is
+ used. If a target defines NEED_SAVED_MASK_IN_CANCEL_JMP_BUF, it
+ must provide its own version of UNEIND_BUF_PRIV. */
+#ifndef UNWIND_BUF_PRIV
+# ifdef NEED_SAVED_MASK_IN_CANCEL_JMP_BUF
+# error "UNWIND_BUF_PRIV is undefined!"
+# endif
+# define UNWIND_BUF_PRIV(self,p) (&((p)->compat.priv))
+#endif
/* Opcodes and data types for communication with the signal handler to
change user/group IDs. */
diff --git a/nptl/pthread_create.c b/nptl/pthread_create.c
index caaf07c..082615e 100644
--- a/nptl/pthread_create.c
+++ b/nptl/pthread_create.c
@@ -428,8 +428,8 @@ START_THREAD_DEFN
struct pthread_unwind_buf unwind_buf;
/* No previous handlers. */
- unwind_buf.priv.data.prev = NULL;
- unwind_buf.priv.data.cleanup = NULL;
+ unwind_buf.full.priv.data.prev = NULL;
+ unwind_buf.full.priv.data.cleanup = NULL;
int not_first_call;
not_first_call = setjmp ((struct __jmp_buf_tag *) unwind_buf.cancel_jmp_buf);
@@ -701,6 +701,11 @@ __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);
diff --git a/nptl/unwind.c b/nptl/unwind.c
index b37a063..f58be0e 100644
--- a/nptl/unwind.c
+++ b/nptl/unwind.c
@@ -66,7 +66,8 @@ unwind_stop (int version, _Unwind_Action actions,
/* Handle the compatibility stuff. Execute all handlers
registered with the old method which would be unwound by this
step. */
- struct _pthread_cleanup_buffer *oldp = buf->priv.data.cleanup;
+ struct _pthread_cleanup_buffer *oldp
+ = UNWIND_BUF_PRIV (self, buf)->data.cleanup;
void *cfa = (void *) (_Unwind_Ptr) _Unwind_GetCFA (context);
if (curp != oldp && (do_longjump || FRAME_LEFT (cfa, curp, adj)))
@@ -133,6 +134,7 @@ __pthread_unwind_next (__pthread_unwind_buf_t *buf)
{
struct pthread_unwind_buf *ibuf = (struct pthread_unwind_buf *) buf;
- __pthread_unwind ((__pthread_unwind_buf_t *) ibuf->priv.data.prev);
+ __pthread_unwind ((__pthread_unwind_buf_t *)
+ UNWIND_BUF_PRIV (THREAD_SELF, ibuf)->data.prev);
}
hidden_def (__pthread_unwind_next)
diff --git a/sysdeps/unix/sysv/linux/x86/nptl/pthreadP.h b/sysdeps/unix/sysv/linux/x86/nptl/pthreadP.h
index 247a62e..ff9ea4c 100644
--- a/sysdeps/unix/sysv/linux/x86/nptl/pthreadP.h
+++ b/sysdeps/unix/sysv/linux/x86/nptl/pthreadP.h
@@ -23,7 +23,7 @@
extern struct pthread_unwind_buf ____pthread_unwind_buf_private;
-_Static_assert (sizeof (____pthread_unwind_buf_private.cancel_jmp_buf)
+_Static_assert (sizeof (____pthread_unwind_buf_private.full.cancel_jmp_buf)
>= sizeof (struct __jmp_buf_tag),
"size of cancel_jmp_buf < sizeof __jmp_buf_tag");
diff --git a/sysdeps/unix/sysv/linux/x86/pthreaddef.h b/sysdeps/unix/sysv/linux/x86/pthreaddef.h
index a405a65..52198ae 100644
--- a/sysdeps/unix/sysv/linux/x86/pthreaddef.h
+++ b/sysdeps/unix/sysv/linux/x86/pthreaddef.h
@@ -20,3 +20,17 @@
/* Need saved_mask in cancel_jmp_buf. */
#define NEED_SAVED_MASK_IN_CANCEL_JMP_BUF 1
+
+/* 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))
+
+/* Use the compatible struct __cancel_jmp_buf_tag if shadow stack is
+ disabled. */
+#undef UNWIND_BUF_PRIV
+#define UNWIND_BUF_PRIV(self,p) \
+ (__extension__ ({ \
+ unsigned int feature_1 = THREAD_GETMEM (self, header.feature_1); \
+ (((feature_1 & (1 << 1)) == 0) \
+ ? &((p)->compat.priv) : &((p)->full.priv));}))
http://sourceware.org/git/gitweb.cgi?p=glibc.git;a=commitdiff;h=048fc0aaf81cd328631b3485e348e3e5723cb826
commit 048fc0aaf81cd328631b3485e348e3e5723cb826
Author: H.J. Lu <hjl.tools@gmail.com>
Date: Fri Jan 26 05:19:15 2018 -0800
Revert "Revert Intel CET changes to __jmp_buf_tag (Bug 22743)"
This reverts commit 2ec0e7eade0ea1258acd5c6f5e5e9bfaeb5041a8.
This is needed to save and restore shadow stack register in setjmp and
longjmp.
[BZ #22563]
* sysdeps/i386/nptl/tcb-offsets.sym (FEATURE_1_OFFSET): New.
* sysdeps/i386/nptl/tls.h (tcbhead_t): Add feature_1.
* 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.
[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.
diff --git a/bits/types/__cancel_jmp_buf_tag.h b/bits/types/__cancel_jmp_buf_tag.h
new file mode 100644
index 0000000..62f5c61
--- /dev/null
+++ b/bits/types/__cancel_jmp_buf_tag.h
@@ -0,0 +1,28 @@
+/* Define struct __cancel_jmp_buf_tag.
+ Copyright (C) 2017-2018 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/>. */
+
+#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
diff --git a/nptl/Makefile b/nptl/Makefile
index 6fc2c8b..7940b3d 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 64ba29e..1cc6b09 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
diff --git a/sysdeps/i386/nptl/tcb-offsets.sym b/sysdeps/i386/nptl/tcb-offsets.sym
index 695a810..250f1a6 100644
--- a/sysdeps/i386/nptl/tcb-offsets.sym
+++ b/sysdeps/i386/nptl/tcb-offsets.sym
@@ -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)
diff --git a/sysdeps/i386/nptl/tls.h b/sysdeps/i386/nptl/tls.h
index fcda135..30643d4 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;
# define TLS_MULTIPLE_THREADS_IN_TCB 1
diff --git a/sysdeps/nptl/pthread.h b/sysdeps/nptl/pthread.h
index df049ab..c8ba5a7 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__));
diff --git a/sysdeps/unix/sysv/linux/hppa/pthread.h b/sysdeps/unix/sysv/linux/hppa/pthread.h
index 11a024d..3df5e7c 100644
--- a/sysdeps/unix/sysv/linux/hppa/pthread.h
+++ b/sysdeps/unix/sysv/linux/hppa/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. */
@@ -499,11 +500,7 @@ 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__));
diff --git a/sysdeps/unix/sysv/linux/x86/bits/types/__cancel_jmp_buf_tag.h b/sysdeps/unix/sysv/linux/x86/bits/types/__cancel_jmp_buf_tag.h
new file mode 100644
index 0000000..70efbb1
--- /dev/null
+++ b/sysdeps/unix/sysv/linux/x86/bits/types/__cancel_jmp_buf_tag.h
@@ -0,0 +1,31 @@
+/* Define struct __cancel_jmp_buf_tag.
+ Copyright (C) 2017-2018 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/>. */
+
+#ifndef ____cancel_jmp_buf_tag_defined
+#define ____cancel_jmp_buf_tag_defined 1
+
+#include <bits/types/__sigset_t.h>
+
+struct __cancel_jmp_buf_tag
+ {
+ __jmp_buf __cancel_jmp_buf;
+ int __mask_was_saved;
+ __sigset_t __saved_mask;
+ };
+
+#endif
diff --git a/sysdeps/unix/sysv/linux/x86/nptl/pthreadP.h b/sysdeps/unix/sysv/linux/x86/nptl/pthreadP.h
new file mode 100644
index 0000000..247a62e
--- /dev/null
+++ b/sysdeps/unix/sysv/linux/x86/nptl/pthreadP.h
@@ -0,0 +1,36 @@
+/* Internal pthread header. Linux/x86 version.
+ Copyright (C) 2017-2018 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 <nptl/pthreadP.h>
+
+#ifndef _PTHREADP_H_X86
+#define _PTHREADP_H_X86 1
+
+extern struct pthread_unwind_buf ____pthread_unwind_buf_private;
+
+_Static_assert (sizeof (____pthread_unwind_buf_private.cancel_jmp_buf)
+ >= sizeof (struct __jmp_buf_tag),
+ "size of cancel_jmp_buf < sizeof __jmp_buf_tag");
+
+extern __pthread_unwind_buf_t ____pthread_unwind_buf;
+
+_Static_assert (sizeof (____pthread_unwind_buf.__cancel_jmp_buf)
+ >= sizeof (struct __jmp_buf_tag),
+ "size of __cancel_jmp_buf < sizeof __jmp_buf_tag");
+
+#endif
diff --git a/sysdeps/unix/sysv/linux/x86/pthreaddef.h b/sysdeps/unix/sysv/linux/x86/pthreaddef.h
new file mode 100644
index 0000000..a405a65
--- /dev/null
+++ b/sysdeps/unix/sysv/linux/x86/pthreaddef.h
@@ -0,0 +1,22 @@
+/* Pthread macros. Linux/x86 version.
+ Copyright (C) 2017-2018 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>
+
+/* Need saved_mask in cancel_jmp_buf. */
+#define NEED_SAVED_MASK_IN_CANCEL_JMP_BUF 1
diff --git a/sysdeps/x86_64/nptl/tcb-offsets.sym b/sysdeps/x86_64/nptl/tcb-offsets.sym
index 8a25c48..03b6dba 100644
--- a/sysdeps/x86_64/nptl/tcb-offsets.sym
+++ b/sysdeps/x86_64/nptl/tcb-offsets.sym
@@ -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
diff --git a/sysdeps/x86_64/nptl/tls.h b/sysdeps/x86_64/nptl/tls.h
index bdd0237..7f0b292 100644
--- a/sysdeps/x86_64/nptl/tls.h
+++ b/sysdeps/x86_64/nptl/tls.h
@@ -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. */
-----------------------------------------------------------------------
hooks/post-receive
--
GNU C Library master sources