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authorH.J. Lu <hjl.tools@gmail.com>2018-07-14 05:53:05 -0700
committerH.J. Lu <hjl.tools@gmail.com>2018-07-14 05:56:46 -0700
commitebff9c5cfae62e84dbd0456d564bd882818dc15f (patch)
treebf8bb50ca20fe7cd8adbac896707bd02975ea1ff /sysdeps/x86
parent0a83bad2aae6807a108d5bb3eb3389060702265b (diff)
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x86: Rename __glibc_reserved1 to feature_1 in tcbhead_t [BZ #22563]
feature_1 has X86_FEATURE_1_IBT and X86_FEATURE_1_SHSTK bits for CET run-time control. CET_ENABLED, IBT_ENABLED and SHSTK_ENABLED are defined to 1 or 0 to indicate that if CET, IBT and SHSTK are enabled. <tls-setup.h> is added to set up thread-local data. Reviewed-by: Carlos O'Donell <carlos@redhat.com> [BZ #22563] * nptl/pthread_create.c: Include <tls-setup.h>. (__pthread_create_2_1): Call tls_setup_tcbhead. * sysdeps/generic/tls-setup.h: New file. * sysdeps/x86/nptl/tls-setup.h: Likewise. * sysdeps/i386/nptl/tcb-offsets.sym (FEATURE_1_OFFSET): New. * sysdeps/x86_64/nptl/tcb-offsets.sym (FEATURE_1_OFFSET): Likewise. * sysdeps/i386/nptl/tls.h (tcbhead_t): Rename __glibc_reserved1 to feature_1. * sysdeps/x86_64/nptl/tls.h (tcbhead_t): Likewise. * sysdeps/x86/sysdep.h (X86_FEATURE_1_IBT): New. (X86_FEATURE_1_SHSTK): Likewise. (CET_ENABLED): Likewise. (IBT_ENABLED): Likewise. (SHSTK_ENABLED): Likewise.
Diffstat (limited to 'sysdeps/x86')
-rw-r--r--sysdeps/x86/nptl/tls-setup.h23
-rw-r--r--sysdeps/x86/sysdep.h27
2 files changed, 50 insertions, 0 deletions
diff --git a/sysdeps/x86/nptl/tls-setup.h b/sysdeps/x86/nptl/tls-setup.h
new file mode 100644
index 0000000000..ef5a4df78c
--- /dev/null
+++ b/sysdeps/x86/nptl/tls-setup.h
@@ -0,0 +1,23 @@
+/* Definitions to set up thread-local data. 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/>. */
+
+static inline void __attribute__ ((always_inline))
+tls_setup_tcbhead (struct pthread *pd)
+{
+ pd->header.feature_1 = THREAD_GETMEM (THREAD_SELF, header.feature_1);
+}
diff --git a/sysdeps/x86/sysdep.h b/sysdeps/x86/sysdep.h
index afcb7cfd76..976566aa37 100644
--- a/sysdeps/x86/sysdep.h
+++ b/sysdeps/x86/sysdep.h
@@ -21,6 +21,33 @@
#include <sysdeps/generic/sysdep.h>
+/* __CET__ is defined by GCC with Control-Flow Protection values:
+
+enum cf_protection_level
+{
+ CF_NONE = 0,
+ CF_BRANCH = 1 << 0,
+ CF_RETURN = 1 << 1,
+ CF_FULL = CF_BRANCH | CF_RETURN,
+ CF_SET = 1 << 2
+};
+*/
+
+/* Set if CF_BRANCH (IBT) is enabled. */
+#define X86_FEATURE_1_IBT (1U << 0)
+/* Set if CF_RETURN (SHSTK) is enabled. */
+#define X86_FEATURE_1_SHSTK (1U << 1)
+
+#ifdef __CET__
+# define CET_ENABLED 1
+# define IBT_ENABLED (__CET__ & X86_FEATURE_1_IBT)
+# define SHSTK_ENABLED (__CET__ & X86_FEATURE_1_SHSTK)
+#else
+# define CET_ENABLED 0
+# define IBT_ENABLED 0
+# define SHSTK_ENABLED 0
+#endif
+
#ifdef __ASSEMBLER__
/* Syntactic details of assembler. */