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[PATCH] [BZ #20309] X86-64: Properly align stack in _dl_tlsdesc_dynamic
- From: "H.J. Lu" <hongjiu dot lu at intel dot com>
- To: GNU C Library <libc-alpha at sourceware dot org>
- Date: Wed, 29 Jun 2016 06:24:11 -0700
- Subject: [PATCH] [BZ #20309] X86-64: Properly align stack in _dl_tlsdesc_dynamic
- Authentication-results: sourceware.org; auth=none
- Reply-to: "H.J. Lu" <hjl dot tools at gmail dot com>
Since _dl_tlsdesc_dynamic is called via PLT, we need to add 8 bytes
for for push in the PLT entry to align the stack.
Tested on i686 and x86-64. OK for trunk?
H.J.
---
[BZ #20309]
* configure.ac (have-mtls-dialect-gnu2): Set to yes if
-mtls-dialect=gnu2 works.
* configure: Regenerated.
* elf/Makefile [have-mtls-dialect-gnu2 = yes]
(tests): Add tst-gnu2-tls1.
(modules-names): Add tst-gnu2-tls1mod.
($(objpfx)tst-gnu2-tls1): New.
(tst-gnu2-tls1mod.so-no-z-defs): Likewise.
(CFLAGS-tst-gnu2-tls1mod.c): Likewise.
* elf/tst-gnu2-tls1.c: New file.
* elf/tst-gnu2-tls1mod.c: Likewise.
* sysdeps/x86_64/dl-tlsdesc.S (_dl_tlsdesc_dynamic): Add 8
bytes for push in the PLT entry to align the stack.
---
configure | 33 ++++++++++++++++++++++++++
configure.ac | 20 ++++++++++++++++
elf/Makefile | 7 ++++++
elf/tst-gnu2-tls1.c | 52 +++++++++++++++++++++++++++++++++++++++++
elf/tst-gnu2-tls1mod.c | 56 +++++++++++++++++++++++++++++++++++++++++++++
sysdeps/x86_64/dl-tlsdesc.S | 13 ++++++-----
6 files changed, 175 insertions(+), 6 deletions(-)
create mode 100644 elf/tst-gnu2-tls1.c
create mode 100644 elf/tst-gnu2-tls1mod.c
diff --git a/configure.ac b/configure.ac
index 123f0d2..33bcd62 100644
--- a/configure.ac
+++ b/configure.ac
@@ -1412,6 +1412,26 @@ elif test "$libc_cv_ssp" = "yes"; then
fi
AC_SUBST(stack_protector)
+AC_CACHE_CHECK([for -mtls-dialect=gnu2], libc_cv_mtls_dialect_gnu2,
+[dnl
+cat > conftest.c <<EOF
+__thread int i;
+void foo (void)
+{
+ i = 10;
+}
+EOF
+if AC_TRY_COMMAND([${CC-cc} $CFLAGS $CPPFLAGS -S -fPIC -mtls-dialect=gnu2
+ conftest.c 1>&AS_MESSAGE_LOG_FD])
+then
+ libc_cv_mtls_dialect_gnu2=yes
+else
+ libc_cv_mtls_dialect_gnu2=no
+fi
+rm -f conftest*])
+AC_SUBST(libc_cv_mtls_dialect_gnu2)
+LIBC_CONFIG_VAR([have-mtls-dialect-gnu2], [$libc_cv_mtls_dialect_gnu2])
+
AC_CACHE_CHECK(whether cc puts quotes around section names,
libc_cv_have_section_quotes,
[cat > conftest.c <<EOF
diff --git a/elf/Makefile b/elf/Makefile
index 210dde9..593403c 100644
--- a/elf/Makefile
+++ b/elf/Makefile
@@ -224,6 +224,13 @@ modules-names = testobj1 testobj2 testobj3 testobj4 testobj5 testobj6 \
tst-tlsalign-lib tst-nodelete-opened-lib tst-nodelete2mod \
tst-audit11mod1 tst-audit11mod2 tst-auditmod11 \
tst-audit12mod1 tst-audit12mod2 tst-audit12mod3 tst-auditmod12
+ifeq (yes,$(have-mtls-dialect-gnu2))
+tests += tst-gnu2-tls1
+modules-names += tst-gnu2-tls1mod
+$(objpfx)tst-gnu2-tls1: $(objpfx)tst-gnu2-tls1mod.so
+tst-gnu2-tls1mod.so-no-z-defs = yes
+CFLAGS-tst-gnu2-tls1mod.c += -mtls-dialect=gnu2
+endif
ifeq (yes,$(have-protected-data))
modules-names += tst-protected1moda tst-protected1modb
tests += tst-protected1a tst-protected1b
diff --git a/elf/tst-gnu2-tls1.c b/elf/tst-gnu2-tls1.c
new file mode 100644
index 0000000..f55de59
--- /dev/null
+++ b/elf/tst-gnu2-tls1.c
@@ -0,0 +1,52 @@
+/* Test local and global dynamic models for GNU2 TLS.
+ Copyright (C) 2016 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 <stdio.h>
+#include <stdlib.h>
+
+extern int * get_gd (void);
+extern void set_gd (int);
+extern int test_gd (int);
+extern int * get_ld (void);
+extern void set_ld (int);
+extern int test_ld (int);
+
+__thread int gd = 1;
+
+static int
+do_test (void)
+{
+ int *p;
+
+ p = get_gd ();
+ set_gd (3);
+ if (*p != 3 || !test_gd (3))
+ abort ();
+
+ p = get_ld ();
+ set_ld (4);
+ if (*p != 4 || !test_ld (4))
+ abort ();
+
+ printf ("PASS\n");
+
+ return 0;
+}
+
+#define TEST_FUNCTION do_test ()
+#include "../test-skeleton.c"
diff --git a/elf/tst-gnu2-tls1mod.c b/elf/tst-gnu2-tls1mod.c
new file mode 100644
index 0000000..45c4816
--- /dev/null
+++ b/elf/tst-gnu2-tls1mod.c
@@ -0,0 +1,56 @@
+/* DSO used by tst-gnu2-tls1.
+ Copyright (C) 2016 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 __thread int ld;
+
+int *
+get_ld (void)
+{
+ return &ld;
+}
+
+void
+set_ld (int i)
+{
+ ld = i;
+}
+
+int
+test_ld (int i)
+{
+ return ld == i;
+}
+extern __thread int gd;
+
+int *
+get_gd (void)
+{
+ return &gd;
+}
+
+void
+set_gd (int i)
+{
+ gd = i;
+}
+
+int
+test_gd (int i)
+{
+ return gd == i;
+}
diff --git a/sysdeps/x86_64/dl-tlsdesc.S b/sysdeps/x86_64/dl-tlsdesc.S
index 3cb7c3d..777f30b 100644
--- a/sysdeps/x86_64/dl-tlsdesc.S
+++ b/sysdeps/x86_64/dl-tlsdesc.S
@@ -163,14 +163,15 @@ _dl_tlsdesc_dynamic:
/* The PLT entry will have pushed the link_map pointer. */
_dl_tlsdesc_resolve_rela:
cfi_adjust_cfa_offset (8)
- /* Save all call-clobbered registers. */
- subq $72, %rsp
- cfi_adjust_cfa_offset (72)
+ /* Save all call-clobbered registers. Add 8 bytes for push in
+ the PLT entry to align the stack. */
+ subq $80, %rsp
+ cfi_adjust_cfa_offset (80)
movq %rax, (%rsp)
movq %rdi, 8(%rsp)
movq %rax, %rdi /* Pass tlsdesc* in %rdi. */
movq %rsi, 16(%rsp)
- movq 72(%rsp), %rsi /* Pass link_map* in %rsi. */
+ movq 80(%rsp), %rsi /* Pass link_map* in %rsi. */
movq %r8, 24(%rsp)
movq %r9, 32(%rsp)
movq %r10, 40(%rsp)
@@ -187,8 +188,8 @@ _dl_tlsdesc_resolve_rela:
movq 48(%rsp), %r11
movq 56(%rsp), %rdx
movq 64(%rsp), %rcx
- addq $80, %rsp
- cfi_adjust_cfa_offset (-80)
+ addq $88, %rsp
+ cfi_adjust_cfa_offset (-88)
jmp *(%rax)
cfi_endproc
.size _dl_tlsdesc_resolve_rela, .-_dl_tlsdesc_resolve_rela
--
2.7.4