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Re: PING: [PATCH] Add --enable-static-pie to build static PIE


On 9/28/17, Joseph Myers <joseph@codesourcery.com> wrote:
> On Wed, 27 Sep 2017, H.J. Lu wrote:
>
>> > static-PIE libraries) - although adding one or two additional
>> > static-PIE
>> > configurations to build-many-glibcs.py might be - but for testing
>> > purposes
>> > it's very useful to understand how widely this option works (or at
>> > least
>> > builds) for other architectures.
>>
>> Many architectures failed to build static PIE due to asm statements in
>> elf_machine_dynamic and elf_machine_load_address.   I didn't check
>> start.S which will fail at run-time if there are any dynamic relocations.
>
> In that case: (a) the install.texi / NEWS entries need to make clear the
> limited nature of architecture support for this feature; (b) if the
> feature achieves consensus to go in mainline at all,
> <https://sourceware.org/glibc/wiki/PortStatus> will need updating with a
> list of all the architectures lacking support and detailed information for
> architecture maintainers regarding how to make the feature work on their
> architectures and how to tell whether it is working.
>

I submitted patches for other targets to address obvious issues with static
PIE.  Build results of build-many-glibcs.py with --enable-static-pie with all
patches for static PIE applied are

PASS: glibcs-aarch64_be-linux-gnu build
PASS: glibcs-aarch64-linux-gnu build
PASS: glibcs-armeb-linux-gnueabi build
PASS: glibcs-armeb-linux-gnueabi-be8 build
PASS: glibcs-armeb-linux-gnueabihf build
PASS: glibcs-armeb-linux-gnueabihf-be8 build
PASS: glibcs-arm-linux-gnueabi build
PASS: glibcs-arm-linux-gnueabihf build
PASS: glibcs-hppa-linux-gnu build
PASS: glibcs-i486-linux-gnu build
PASS: glibcs-i586-linux-gnu build
PASS: glibcs-i686-linux-gnu build
PASS: glibcs-i686-linux-gnu-disable-multi-arch build
PASS: glibcs-m68k-linux-gnu build
PASS: glibcs-microblazeel-linux-gnu build
PASS: glibcs-microblaze-linux-gnu build
PASS: glibcs-mips64el-linux-gnu-n64 build
PASS: glibcs-mips64el-linux-gnu-n64-nan2008 build
PASS: glibcs-mips64el-linux-gnu-n64-nan2008-soft build
PASS: glibcs-mips64el-linux-gnu-n64-soft build
PASS: glibcs-mips64-linux-gnu-n64 build
PASS: glibcs-mips64-linux-gnu-n64-nan2008 build
PASS: glibcs-mips64-linux-gnu-n64-nan2008-soft build
PASS: glibcs-mips64-linux-gnu-n64-soft build
PASS: glibcs-nios2-linux-gnu build
PASS: glibcs-powerpc64le-linux-gnu build
PASS: glibcs-powerpc64-linux-gnu build
PASS: glibcs-s390x-linux-gnu build
PASS: glibcs-x86_64-linux-gnu build
PASS: glibcs-x86_64-linux-gnu-disable-multi-arch build
PASS: glibcs-x86_64-linux-gnu-x32 build

FAIL: glibcs-alpha-linux-gnu build

elf/sln is failed to link due to:

assertion fail bfd/elf64-alpha.c:4125

This is caused by linker bug and/or non-PIC code in PIE libc.a.

FAIL: glibcs-ia64-linux-gnu build

elf/sln is failed to link due to:

libc.a(sched_yield.o): non-pic code with imm relocation against
dynamic symbol `_dl_sysinfo'

This is caused by non-PICi version of DO_CALL macro in ia64 sysdep.h.  PIE
libc.a should use PIC version of DO_CALL, except during startup in static
PIE.  An ia64 startup.h, similar to i386 startup.h, is needed to handle
this.

FAIL: glibcs-mips64el-linux-gnu-n32 build
FAIL: glibcs-mips64el-linux-gnu-n32-nan2008 build
FAIL: glibcs-mips64el-linux-gnu-n32-nan2008-soft build
FAIL: glibcs-mips64el-linux-gnu-n32-soft build
FAIL: glibcs-mips64-linux-gnu-n32 build
FAIL: glibcs-mips64-linux-gnu-n32-nan2008 build
FAIL: glibcs-mips64-linux-gnu-n32-nan2008-soft build
FAIL: glibcs-mips64-linux-gnu-n32-soft build
FAIL: glibcs-mipsel-linux-gnu build
FAIL: glibcs-mipsel-linux-gnu-nan2008 build
FAIL: glibcs-mipsel-linux-gnu-nan2008-soft build
FAIL: glibcs-mipsel-linux-gnu-soft build
FAIL: glibcs-mips-linux-gnu build
FAIL: glibcs-mips-linux-gnu-nan2008 build
FAIL: glibcs-mips-linux-gnu-nan2008-soft build
FAIL: glibcs-mips-linux-gnu-soft build

elf/sln is failed to link due to:

crt1.o: relocation R_MIPS_HI16 against `_gp' can not be used when
making a shared object; recompile with -fPIC

This is caused by linker bug and/or non-PIC code in crt1.o.

FAIL: glibcs-powerpc-linux-gnu build
FAIL: glibcs-powerpc-linux-gnu-soft build
FAIL: glibcs-powerpc-linux-gnuspe build
FAIL: glibcs-powerpc-linux-gnuspe-e500v1 build

elf/sln is failed to link due to:

ld: read-only segment has dynamic relocations.

This is caused by linker bug and/or non-PIC code in PIE libc.a.

FAIL: glibcs-powerpc-linux-gnu-power4 build

elf/sln is failed to link due to:

findlocale.c:96:(.text+0x22c): @local call to ifunc memchr

This is caused by linker bug and/or non-PIC code in PIE libc.a.

FAIL: glibcs-s390-linux-gnu build

elf/sln is failed to link due to:

collect2: fatal error: ld terminated with signal 11 [Segmentation
fault], core dumped

assertion fail bfd/elflink.c:14242

This is caused by linker bug and/or non-PIC code in PIE libc.a.

FAIL: glibcs-sh3eb-linux-gnu build
FAIL: glibcs-sh3-linux-gnu build
FAIL: glibcs-sh4eb-linux-gnu build
FAIL: glibcs-sh4eb-linux-gnu-soft build
FAIL: glibcs-sh4-linux-gnu build
FAIL: glibcs-sh4-linux-gnu-soft build

elf/sln is failed to link due to:

ld: read-only segment has dynamic relocations.

This is caused by linker bug and/or non-PIC code in PIE libc.a.

FAIL: glibcs-sparc64-linux-gnu build
FAIL: glibcs-sparcv9-linux-gnu build

elf/sln is failed to link due to:

ld: read-only segment has dynamic relocations.

This is caused by linker bug and/or non-PIC code in PIE libc.a.

FAIL: glibcs-tilegxbe-linux-gnu build
FAIL: glibcs-tilegxbe-linux-gnu-32 build
FAIL: glibcs-tilegx-linux-gnu build
FAIL: glibcs-tilegx-linux-gnu-32 build
FAIL: glibcs-tilepro-linux-gnu build

elf/sln is failed to link due to:

ld: read-only segment has dynamic relocations.

This is caused by linker bug and/or non-PIC code in PIE libc.a.

Here is the updated patch to state that i686, x86-64 and x32 targets
are verified to work.  I encourage target maintainers to try hjl/pie/static
branch to verify if static PIE works for your targets.

Thanks.

-- 
H.J.
From 6a63037b178d88e07dccc371ab6611395e173b9a Mon Sep 17 00:00:00 2001
From: "H.J. Lu" <hjl.tools@gmail.com>
Date: Mon, 17 Jul 2017 08:17:32 -0700
Subject: [PATCH] Add --enable-static-pie configure option to build
 static PIE

Dynamic linker, ld.so, is a standalone program which can be loaded at
any address.  This patch adds a configure option, --enable-static-pie,
to embed the part of ld.so in static executable to create static position
independent executable (static PIE).  A static PIE is similar to static
executable, but can be loaded at any address without help from a dynamic
linker.  When --enable-static-pie is used to configure glibc, libc.a is
built as PIE and all static executables, including tests, are built as
static PIE.  The resulting libc.a can be used together with GCC 8 or
above to build static PIE with the compiler option, -static-pie.  But
GCC 8 isn't required to build glibc with --enable-static-pie.  When an
older GCC is used to build glibc with --enable-static-pie, proper input
files are passed to linker to create static executables as static PIE,
together with "-z text" to prevent dynamic relocations in read-only
segments, which are allowed in static PIE.

Static PIE can work on all architectures which support PIE, provided

1. start.S is updated to check PIC instead SHARED for PIC code path and
avoid dynamic relocation, when PIC is defined and SHARED isn't defined,
to support static PIE.  Patches are submitted for aarch64, arm, hppa,
m68k, microblaze and sparc.
2. All assembly codes are updated check PIC instead SHARED for PIC code
path to avoid dynamic relocations in read-only sections.
3. All assembly codes are updated check SHARED instead PIC for static
symbol name.  A patch is submitted for tile.
4. elf_machine_load_address in dl-machine.h are updated to support static
PIE.  Patches are submitted for aarch64, arm, hppa, ia64, m68k, microblaze,
mips, nios2, powerpc, s390, sh, sparc and tile.

NB: When glibc is built with GCC defaulted to PIE, libc.a is compiled
with -fPIE, regardless if --enable-static-pie is used to configure glibc.
When glibc is configured with --enable-static-pie, libc.a is compiled
with -fPIE, regardless wether GCC defaults to PIE or not.  The same libc.a
can be used to build both static executable and static PIE.  There is no
need for separate PIE copy of libc.a.

Linker requirements to build glibc with --enable-static-pie:

1. Linker supports --no-dynamic-linker to remove PT_INTERP segment from
static PIE.
2. Linker can create working static PIE.  The x86-64 linker needs the
fix for

https://sourceware.org/bugzilla/show_bug.cgi?id=21782

Binutils 2.29 or above are OK for x86-64.  But linker status for other
targets need to be verified.

Tested on i686 and x86-64.

Build results of build-many-glibcs.py with --enable-static-pie with all
patches for static PIE applied are

PASS: glibcs-aarch64_be-linux-gnu build
PASS: glibcs-aarch64-linux-gnu build
PASS: glibcs-armeb-linux-gnueabi build
PASS: glibcs-armeb-linux-gnueabi-be8 build
PASS: glibcs-armeb-linux-gnueabihf build
PASS: glibcs-armeb-linux-gnueabihf-be8 build
PASS: glibcs-arm-linux-gnueabi build
PASS: glibcs-arm-linux-gnueabihf build
PASS: glibcs-hppa-linux-gnu build
PASS: glibcs-i486-linux-gnu build
PASS: glibcs-i586-linux-gnu build
PASS: glibcs-i686-linux-gnu build
PASS: glibcs-i686-linux-gnu-disable-multi-arch build
PASS: glibcs-m68k-linux-gnu build
PASS: glibcs-microblazeel-linux-gnu build
PASS: glibcs-microblaze-linux-gnu build
PASS: glibcs-mips64el-linux-gnu-n64 build
PASS: glibcs-mips64el-linux-gnu-n64-nan2008 build
PASS: glibcs-mips64el-linux-gnu-n64-nan2008-soft build
PASS: glibcs-mips64el-linux-gnu-n64-soft build
PASS: glibcs-mips64-linux-gnu-n64 build
PASS: glibcs-mips64-linux-gnu-n64-nan2008 build
PASS: glibcs-mips64-linux-gnu-n64-nan2008-soft build
PASS: glibcs-mips64-linux-gnu-n64-soft build
PASS: glibcs-nios2-linux-gnu build
PASS: glibcs-powerpc64le-linux-gnu build
PASS: glibcs-powerpc64-linux-gnu build
PASS: glibcs-s390x-linux-gnu build
PASS: glibcs-x86_64-linux-gnu build
PASS: glibcs-x86_64-linux-gnu-disable-multi-arch build
PASS: glibcs-x86_64-linux-gnu-x32 build

FAIL: glibcs-alpha-linux-gnu build

elf/sln is failed to link due to:

assertion fail bfd/elf64-alpha.c:4125

This is caused by linker bug and/or non-PIC code in PIE libc.a.

FAIL: glibcs-ia64-linux-gnu build

elf/sln is failed to link due to:

libc.a(sched_yield.o): non-pic code with imm relocation against dynamic symbol `_dl_sysinfo'

This is caused by non-PICi version of DO_CALL macro in ia64 sysdep.h.  PIE
libc.a should use PIC version of DO_CALL, except during startup in static
PIE.  An ia64 startup.h, similar to i386 startup.h, is needed to handle
this.

FAIL: glibcs-mips64el-linux-gnu-n32 build
FAIL: glibcs-mips64el-linux-gnu-n32-nan2008 build
FAIL: glibcs-mips64el-linux-gnu-n32-nan2008-soft build
FAIL: glibcs-mips64el-linux-gnu-n32-soft build
FAIL: glibcs-mips64-linux-gnu-n32 build
FAIL: glibcs-mips64-linux-gnu-n32-nan2008 build
FAIL: glibcs-mips64-linux-gnu-n32-nan2008-soft build
FAIL: glibcs-mips64-linux-gnu-n32-soft build
FAIL: glibcs-mipsel-linux-gnu build
FAIL: glibcs-mipsel-linux-gnu-nan2008 build
FAIL: glibcs-mipsel-linux-gnu-nan2008-soft build
FAIL: glibcs-mipsel-linux-gnu-soft build
FAIL: glibcs-mips-linux-gnu build
FAIL: glibcs-mips-linux-gnu-nan2008 build
FAIL: glibcs-mips-linux-gnu-nan2008-soft build
FAIL: glibcs-mips-linux-gnu-soft build

elf/sln is failed to link due to:

crt1.o: relocation R_MIPS_HI16 against `_gp' can not be used when making a shared object; recompile with -fPIC

This is caused by linker bug and/or non-PIC code in crt1.o.

FAIL: glibcs-powerpc-linux-gnu build
FAIL: glibcs-powerpc-linux-gnu-soft build
FAIL: glibcs-powerpc-linux-gnuspe build
FAIL: glibcs-powerpc-linux-gnuspe-e500v1 build

elf/sln is failed to link due to:

ld: read-only segment has dynamic relocations.

This is caused by linker bug and/or non-PIC code in PIE libc.a.

FAIL: glibcs-powerpc-linux-gnu-power4 build

elf/sln is failed to link due to:

findlocale.c:96:(.text+0x22c): @local call to ifunc memchr

This is caused by linker bug and/or non-PIC code in PIE libc.a.

FAIL: glibcs-s390-linux-gnu build

elf/sln is failed to link due to:

collect2: fatal error: ld terminated with signal 11 [Segmentation fault], core dumped

assertion fail bfd/elflink.c:14242

This is caused by linker bug and/or non-PIC code in PIE libc.a.

FAIL: glibcs-sh3eb-linux-gnu build
FAIL: glibcs-sh3-linux-gnu build
FAIL: glibcs-sh4eb-linux-gnu build
FAIL: glibcs-sh4eb-linux-gnu-soft build
FAIL: glibcs-sh4-linux-gnu build
FAIL: glibcs-sh4-linux-gnu-soft build

elf/sln is failed to link due to:

ld: read-only segment has dynamic relocations.

This is caused by linker bug and/or non-PIC code in PIE libc.a.

FAIL: glibcs-sparc64-linux-gnu build
FAIL: glibcs-sparcv9-linux-gnu build

elf/sln is failed to link due to:

ld: read-only segment has dynamic relocations.

This is caused by linker bug and/or non-PIC code in PIE libc.a.

FAIL: glibcs-tilegxbe-linux-gnu build
FAIL: glibcs-tilegxbe-linux-gnu-32 build
FAIL: glibcs-tilegx-linux-gnu build
FAIL: glibcs-tilegx-linux-gnu-32 build
FAIL: glibcs-tilepro-linux-gnu build

elf/sln is failed to link due to:

ld: read-only segment has dynamic relocations.

This is caused by linker bug and/or non-PIC code in PIE libc.a.

	* INSTALL: Regenerated.
	* Makeconfig (pic-default): Updated for --enable-static-pie.
	(pie-default): New for --enable-static-pie.
	(default-pie-ldflag): Likewise.
	(+link-static-before-libc): Add $(default-pie-ldflag).
	(+prectorT): Updated for --enable-static-pie.
	(+postctorT): Likewise.
	(CFLAGS-.o): Add $(pie-default).
	(CFLAGS-.op): Likewise.
	* NEWS: Mention --enable-static-pie.
	* config.h.in (ENABLE_STATIC_PIE): New.
	* configure.ac (--enable-static-pie): New configure option.
	(have-no-dynamic-linker): New LIBC_CONFIG_VAR.
	(have-static-pie): Likewise.
	Enable static PIE if linker supports --no-dynamic-linker.
	(ENABLE_STATIC_PIE): New AC_DEFINE.
	(enable-static-pie): New LIBC_CONFIG_VAR.
	* configure: Regenerated.
	* csu/libc-start.c (LIBC_START_MAIN): Call _dl_relocate_static_pie
	in libc.a.
	* csu/libc-tls.c (__libc_setup_tls): Add main_map->l_addr to
	initimage.
	* elf/dl-support.c: Include "dynamic-link.h" and don't include
	"get-dynamic-info.h" for --enable-static-pie.
	(_dl_relocate_static_pie): New function for --enable-static-pie.
	(STATIC_PIE_BOOTSTRAP): New for --enable-static-pie.
	(BOOTSTRAP_MAP): Likewise.
	(RESOLVE_MAP): Likewise.
	* elf/dynamic-link.h (ELF_DURING_STARTUP): Also check
	STATIC_PIE_BOOTSTRAP.
	* elf/get-dynamic-info.h (elf_get_dynamic_info): Likewise.
	* manual/install.texi: Document --enable-static-pie.
	* sysdeps/generic/ldsodefs.h (_dl_relocate_static_pie): New.
	* sysdeps/x86_64/configure.ac: Check if linker supports static PIE.
	* sysdeps/x86_64/configure: Regenerated.
---
 INSTALL                     |  8 +++++
 Makeconfig                  | 20 ++++++++++--
 NEWS                        |  6 ++++
 config.h.in                 |  3 ++
 configure                   | 78 +++++++++++++++++++++++++++++++++++++++++++++
 configure.ac                | 29 +++++++++++++++++
 csu/libc-start.c            |  2 ++
 csu/libc-tls.c              |  6 ++--
 elf/dl-support.c            | 44 +++++++++++++++++++++++--
 elf/dynamic-link.h          |  2 +-
 elf/get-dynamic-info.h      |  6 ++--
 manual/install.texi         |  8 +++++
 sysdeps/generic/ldsodefs.h  |  7 ++++
 sysdeps/x86_64/configure    | 33 +++++++++++++++++++
 sysdeps/x86_64/configure.ac | 25 +++++++++++++++
 15 files changed, 267 insertions(+), 10 deletions(-)

diff --git a/INSTALL b/INSTALL
index 4d9024c667..55361a0fd3 100644
--- a/INSTALL
+++ b/INSTALL
@@ -106,6 +106,14 @@ will be used, and CFLAGS sets optimization options for the compiler.
      systems support shared libraries; you need ELF support and
      (currently) the GNU linker.
 
+'--enable-static-pie'
+     Build static executables, including tests, as position independent
+     executable (static PIE) which is similar to static executable, but
+     can be loaded at any address without help from a dynamic linker.
+     The resulting libc.a can be used with the GCC option, -static-pie,
+     which is available with GCC 8 or above, to create static PIE. Only
+     i686, x86-64 and x32 targets are verified to work.
+
 '--disable-profile'
      Don't build libraries with profiling information.  You may want to
      use this option if you don't plan to do profiling.
diff --git a/Makeconfig b/Makeconfig
index b51904b797..b45209fe5f 100644
--- a/Makeconfig
+++ b/Makeconfig
@@ -386,6 +386,16 @@ LDFLAGS.so += $(hashstyle-LDFLAGS)
 LDFLAGS-rtld += $(hashstyle-LDFLAGS)
 endif
 
+ifeq (yes,$(enable-static-pie))
+pic-default = -DPIC
+pie-default = $(pie-ccflag)
+ifeq (yes,$(have-static-pie))
+default-pie-ldflag = -static-pie
+else
+default-pie-ldflag = -Wl,-pie,--no-dynamic-linker,--eh-frame-hdr,-z,text
+endif
+endif
+
 # If lazy relocations are disabled, add the -z now flag.  Use
 # LDFLAGS-lib.so instead of LDFLAGS.so, to avoid adding the flag to
 # test modules.
@@ -435,6 +445,7 @@ endif
 # Command for statically linking programs with the C library.
 ifndef +link-static
 +link-static-before-libc = $(CC) -nostdlib -nostartfiles -static -o $@ \
+	      $(default-pie-ldflag) \
 	      $(sysdep-LDFLAGS) $(LDFLAGS) $(LDFLAGS-$(@F))  \
 	      $(addprefix $(csu-objpfx),$(static-start-installed-name)) \
 	      $(+preinit) $(+prectorT) \
@@ -651,8 +662,13 @@ endif
 +prectorS = `$(CC) $(sysdep-LDFLAGS) --print-file-name=crtbeginS.o`
 +postctorS = `$(CC) $(sysdep-LDFLAGS) --print-file-name=crtendS.o`
 # Variants of the two previous definitions for statically linking programs.
+ifeq (yes,$(enable-static-pie))
++prectorT = $(+prectorS)
++postctorT = $(+postctorS)
+else
 +prectorT = `$(CC) $(sysdep-LDFLAGS) --print-file-name=crtbeginT.o`
 +postctorT = `$(CC) $(sysdep-LDFLAGS) --print-file-name=crtend.o`
+endif
 csu-objpfx = $(common-objpfx)csu/
 elf-objpfx = $(common-objpfx)elf/
 
@@ -973,7 +989,7 @@ libtypes = $(foreach o,$(object-suffixes-for-libc),$(libtype$o))
 all-object-suffixes := .o .os .oS
 object-suffixes :=
 CPPFLAGS-.o = $(pic-default)
-CFLAGS-.o = $(filter %frame-pointer,$(+cflags))
+CFLAGS-.o = $(filter %frame-pointer,$(+cflags)) $(pie-default)
 libtype.o := lib%.a
 object-suffixes += .o
 ifeq (yes,$(build-shared))
@@ -998,7 +1014,7 @@ ifeq (yes,$(build-profile))
 all-object-suffixes += .op
 object-suffixes += .op
 CPPFLAGS-.op = -DPROF $(pic-default)
-CFLAGS-.op = -pg
+CFLAGS-.op = -pg $(pie-default)
 libtype.op = lib%_p.a
 endif
 
diff --git a/NEWS b/NEWS
index f5821411ca..60f5def617 100644
--- a/NEWS
+++ b/NEWS
@@ -9,6 +9,12 @@ Version 2.27
 
 Major new features:
 
+* Add --enable-static-pie configure option to build static PIE.  The
+  resulting libc.a can be used with the GCC option, -static-pie, which
+  is available with GCC 8 or above, to create static position independent
+  executable (static PIE).  Only i686, x86-64 and x32 targets are verified
+  to work.
+
 * Optimized x86-64 asin, atan2, exp, expf, log, pow, atan, sin and tan
   with FMA, contributed by Arjan van de Ven and H.J. Lu from Intel.
 
diff --git a/config.h.in b/config.h.in
index 014fb4ea0e..26ed7865ef 100644
--- a/config.h.in
+++ b/config.h.in
@@ -236,6 +236,9 @@
 /* Build glibc with tunables support.  */
 #define HAVE_TUNABLES 0
 
+/* Define if static PIE is enabled.  */
+#define ENABLE_STATIC_PIE 0
+
 /* Some compiler options may now allow to use ebp in __asm__ (used mainly
    in i386 6 argument syscall issue).  */
 #define CAN_USE_REGISTER_ASM_EBP 0
diff --git a/configure b/configure
index 067d92d2ba..cd5cf5729f 100755
--- a/configure
+++ b/configure
@@ -767,6 +767,7 @@ with_default_link
 enable_sanity_checks
 enable_shared
 enable_profile
+enable_static_pie
 enable_timezone_tools
 enable_hardcoded_path_in_tests
 enable_stackguard_randomization
@@ -1424,6 +1425,7 @@ Optional Features:
                           in special situations) [default=yes]
   --enable-shared         build shared library [default=yes if GNU ld]
   --enable-profile        build profiled library [default=no]
+  --enable-static-pie     build static executables as PIE [default=no]
   --disable-timezone-tools
                           do not install timezone tools [default=install]
   --enable-hardcoded-path-in-tests
@@ -3372,6 +3374,13 @@ else
   profile=no
 fi
 
+# Check whether --enable-static-pie was given.
+if test "${enable_static_pie+set}" = set; then :
+  enableval=$enable_static_pie; static_pie=$enableval
+else
+  static_pie=no
+fi
+
 # Check whether --enable-timezone-tools was given.
 if test "${enable_timezone_tools+set}" = set; then :
   enableval=$enable_timezone_tools; enable_timezone_tools=$enableval
@@ -5994,6 +6003,62 @@ fi
 $as_echo "$libc_linker_feature" >&6; }
 
 
+{ $as_echo "$as_me:${as_lineno-$LINENO}: checking for linker that supports --no-dynamic-linker" >&5
+$as_echo_n "checking for linker that supports --no-dynamic-linker... " >&6; }
+libc_linker_feature=no
+if test x"$gnu_ld" = x"yes"; then
+  libc_linker_check=`$LD -v --help 2>/dev/null | grep "\--no-dynamic-linker"`
+  if test -n "$libc_linker_check"; then
+    cat > conftest.c <<EOF
+int _start (void) { return 42; }
+EOF
+    if { ac_try='${CC-cc} $CFLAGS $CPPFLAGS $LDFLAGS $no_ssp
+				-Wl,--no-dynamic-linker -nostdlib -nostartfiles
+				-fPIC -shared -o conftest.so conftest.c
+				1>&5'
+  { { eval echo "\"\$as_me\":${as_lineno-$LINENO}: \"$ac_try\""; } >&5
+  (eval $ac_try) 2>&5
+  ac_status=$?
+  $as_echo "$as_me:${as_lineno-$LINENO}: \$? = $ac_status" >&5
+  test $ac_status = 0; }; }
+    then
+      libc_linker_feature=yes
+    fi
+    rm -f conftest*
+  fi
+fi
+if test $libc_linker_feature = yes; then
+  libc_cv_no_dynamic_linker=yes
+else
+  libc_cv_no_dynamic_linker=no
+fi
+{ $as_echo "$as_me:${as_lineno-$LINENO}: result: $libc_linker_feature" >&5
+$as_echo "$libc_linker_feature" >&6; }
+config_vars="$config_vars
+have-no-dynamic-linker = $libc_cv_no_dynamic_linker"
+
+{ $as_echo "$as_me:${as_lineno-$LINENO}: checking for -static-pie" >&5
+$as_echo_n "checking for -static-pie... " >&6; }
+if ${libc_cv_static_pie+:} false; then :
+  $as_echo_n "(cached) " >&6
+else
+  if { ac_try='${CC-cc} -static-pie -xc /dev/null -S -o /dev/null'
+  { { eval echo "\"\$as_me\":${as_lineno-$LINENO}: \"$ac_try\""; } >&5
+  (eval $ac_try) 2>&5
+  ac_status=$?
+  $as_echo "$as_me:${as_lineno-$LINENO}: \$? = $ac_status" >&5
+  test $ac_status = 0; }; }; then :
+  libc_cv_static_pie=yes
+else
+  libc_cv_static_pie=no
+fi
+
+fi
+{ $as_echo "$as_me:${as_lineno-$LINENO}: result: $libc_cv_static_pie" >&5
+$as_echo "$libc_cv_static_pie" >&6; }
+config_vars="$config_vars
+have-static-pie = $libc_cv_static_pie"
+
 { $as_echo "$as_me:${as_lineno-$LINENO}: checking for -fpie" >&5
 $as_echo_n "checking for -fpie... " >&6; }
 if ${libc_cv_fpie+:} false; then :
@@ -6888,6 +6953,19 @@ fi
 $as_echo "$libc_cv_pie_default" >&6; }
 
 
+if test "$static_pie" = yes; then
+  # The linker must support --no-dynamic-linker.
+  if test "$libc_cv_no_dynamic_linker" != yes; then
+    as_fn_error $? "linker support for --no-dynamic-linker needed" "$LINENO" 5
+  fi
+  # Default to PIE.
+  libc_cv_pie_default=yes
+  $as_echo "#define ENABLE_STATIC_PIE 1" >>confdefs.h
+
+fi
+config_vars="$config_vars
+enable-static-pie = $static_pie"
+
 
 
 
diff --git a/configure.ac b/configure.ac
index d412104d8c..09e1c7f23b 100644
--- a/configure.ac
+++ b/configure.ac
@@ -176,6 +176,11 @@ AC_ARG_ENABLE([profile],
 			     [build profiled library @<:@default=no@:>@]),
 	      [profile=$enableval],
 	      [profile=no])
+AC_ARG_ENABLE([static-pie],
+	      AC_HELP_STRING([--enable-static-pie],
+			     [build static executables as PIE @<:@default=no@:>@]),
+	      [static_pie=$enableval],
+	      [static_pie=no])
 AC_ARG_ENABLE([timezone-tools],
 	      AC_HELP_STRING([--disable-timezone-tools],
 			     [do not install timezone tools @<:@default=install@:>@]),
@@ -1460,6 +1465,19 @@ LIBC_LINKER_FEATURE([-z execstack], [-Wl,-z,execstack],
 		    [libc_cv_z_execstack=yes], [libc_cv_z_execstack=no])
 AC_SUBST(libc_cv_z_execstack)
 
+LIBC_LINKER_FEATURE([--no-dynamic-linker],
+		    [-Wl,--no-dynamic-linker],
+		    [libc_cv_no_dynamic_linker=yes],
+		    [libc_cv_no_dynamic_linker=no])
+LIBC_CONFIG_VAR([have-no-dynamic-linker], [$libc_cv_no_dynamic_linker])
+
+AC_CACHE_CHECK(for -static-pie, libc_cv_static_pie, [dnl
+LIBC_TRY_CC_OPTION([-static-pie],
+		   [libc_cv_static_pie=yes],
+		   [libc_cv_static_pie=no])
+])
+LIBC_CONFIG_VAR([have-static-pie], [$libc_cv_static_pie])
+
 AC_CACHE_CHECK(for -fpie, libc_cv_fpie, [dnl
 LIBC_TRY_CC_OPTION([-fpie], [libc_cv_fpie=yes], [libc_cv_fpie=no])
 ])
@@ -1962,6 +1980,17 @@ fi
 rm -f conftest.*])
 AC_SUBST(libc_cv_pie_default)
 
+if test "$static_pie" = yes; then
+  # The linker must support --no-dynamic-linker.
+  if test "$libc_cv_no_dynamic_linker" != yes; then
+    AC_MSG_ERROR([linker support for --no-dynamic-linker needed])
+  fi
+  # Default to PIE.
+  libc_cv_pie_default=yes
+  AC_DEFINE(ENABLE_STATIC_PIE)
+fi
+LIBC_CONFIG_VAR([enable-static-pie], [$static_pie])
+
 AC_SUBST(profile)
 AC_SUBST(static_nss)
 
diff --git a/csu/libc-start.c b/csu/libc-start.c
index 24c63be02f..34dd125260 100644
--- a/csu/libc-start.c
+++ b/csu/libc-start.c
@@ -141,6 +141,8 @@ LIBC_START_MAIN (int (*main) (int, char **, char ** MAIN_AUXVEC_DECL),
   __libc_multiple_libcs = &_dl_starting_up && !_dl_starting_up;
 
 #ifndef SHARED
+  _dl_relocate_static_pie ();
+
   char **ev = &argv[argc + 1];
 
   __environ = ev;
diff --git a/csu/libc-tls.c b/csu/libc-tls.c
index 00138eb43a..1f8ddaf543 100644
--- a/csu/libc-tls.c
+++ b/csu/libc-tls.c
@@ -114,6 +114,8 @@ __libc_setup_tls (void)
   size_t tcb_offset;
   const ElfW(Phdr) *phdr;
 
+  struct link_map *main_map = GL(dl_ns)[LM_ID_BASE]._ns_loaded;
+
   /* Look through the TLS segment if there is any.  */
   if (_dl_phdr != NULL)
     for (phdr = _dl_phdr; phdr < &_dl_phdr[_dl_phnum]; ++phdr)
@@ -122,7 +124,7 @@ __libc_setup_tls (void)
 	  /* Remember the values we need.  */
 	  memsz = phdr->p_memsz;
 	  filesz = phdr->p_filesz;
-	  initimage = (void *) phdr->p_vaddr;
+	  initimage = (void *) phdr->p_vaddr + main_map->l_addr;
 	  align = phdr->p_align;
 	  if (phdr->p_align > max_align)
 	    max_align = phdr->p_align;
@@ -163,8 +165,6 @@ __libc_setup_tls (void)
   _dl_static_dtv[0].counter = (sizeof (_dl_static_dtv) / sizeof (_dl_static_dtv[0])) - 2;
   // _dl_static_dtv[1].counter = 0;		would be needed if not already done
 
-  struct link_map *main_map = GL(dl_ns)[LM_ID_BASE]._ns_loaded;
-
   /* Initialize the TLS block.  */
 #if TLS_TCB_AT_TP
   _dl_static_dtv[2].pointer.val = ((char *) tlsblock + tcb_offset
diff --git a/elf/dl-support.c b/elf/dl-support.c
index 5e3de90598..150ec00f9d 100644
--- a/elf/dl-support.c
+++ b/elf/dl-support.c
@@ -26,7 +26,11 @@
 #include <sys/param.h>
 #include <stdint.h>
 #include <ldsodefs.h>
-#include <dl-machine.h>
+#if ENABLE_STATIC_PIE
+# include "dynamic-link.h"
+#else
+# include <dl-machine.h>
+#endif
 #include <libc-lock.h>
 #include <dl-cache.h>
 #include <dl-librecon.h>
@@ -199,7 +203,9 @@ const ElfW(Ehdr) *_dl_sysinfo_dso;
 
 struct link_map *_dl_sysinfo_map;
 
-# include "get-dynamic-info.h"
+# if !ENABLE_STATIC_PIE
+#  include "get-dynamic-info.h"
+# endif
 #endif
 #include "setup-vdso.h"
 
@@ -302,6 +308,40 @@ _dl_aux_init (ElfW(auxv_t) *av)
 }
 #endif
 
+#if ENABLE_STATIC_PIE
+/* Relocate static executable with PIE.  */
+
+void
+_dl_relocate_static_pie (void)
+{
+# define STATIC_PIE_BOOTSTRAP
+# define BOOTSTRAP_MAP (&_dl_main_map)
+# define RESOLVE_MAP(sym, version, flags) BOOTSTRAP_MAP
+# include "dynamic-link.h"
+
+  /* Figure out the run-time load addres of static PIE.  */
+  _dl_main_map.l_addr = elf_machine_load_address ();
+
+  /* Skip if this is a non-PIE static executable.  */
+  if (!_dl_main_map.l_addr)
+    return;
+
+  /* Read our own dynamic section and fill in the info array.  */
+  _dl_main_map.l_ld = ((void *) _dl_main_map.l_addr
+		       + elf_machine_dynamic ());
+  elf_get_dynamic_info (&_dl_main_map, NULL);
+
+# ifdef ELF_MACHINE_BEFORE_RTLD_RELOC
+  ELF_MACHINE_BEFORE_RTLD_RELOC (_dl_main_map.l_info);
+# endif
+
+  /* Relocate ourselves so we can do normal function calls and
+     data access using the global offset table.  */
+  ELF_DYNAMIC_RELOCATE (&_dl_main_map, 0, 0, 0);
+  _dl_main_map.l_relocated = 1;
+}
+#endif
+
 
 void
 _dl_non_dynamic_init (void)
diff --git a/elf/dynamic-link.h b/elf/dynamic-link.h
index ebea7567cd..6278649711 100644
--- a/elf/dynamic-link.h
+++ b/elf/dynamic-link.h
@@ -94,7 +94,7 @@ elf_machine_lazy_rel (struct link_map *map,
 
 #ifdef RESOLVE_MAP
 
-# ifdef RTLD_BOOTSTRAP
+# if defined RTLD_BOOTSTRAP || defined STATIC_PIE_BOOTSTRAP
 #  define ELF_DURING_STARTUP (1)
 # else
 #  define ELF_DURING_STARTUP (0)
diff --git a/elf/get-dynamic-info.h b/elf/get-dynamic-info.h
index 7525c3a5b2..eb26d23649 100644
--- a/elf/get-dynamic-info.h
+++ b/elf/get-dynamic-info.h
@@ -38,7 +38,7 @@ elf_get_dynamic_info (struct link_map *l, ElfW(Dyn) *temp)
   typedef Elf64_Xword d_tag_utype;
 #endif
 
-#ifndef RTLD_BOOTSTRAP
+#if !defined RTLD_BOOTSTRAP && !defined STATIC_PIE_BOOTSTRAP
   if (dyn == NULL)
     return;
 #endif
@@ -139,9 +139,11 @@ elf_get_dynamic_info (struct link_map *l, ElfW(Dyn) *temp)
   /* Only the bind now flags are allowed.  */
   assert (info[VERSYMIDX (DT_FLAGS_1)] == NULL
 	  || (info[VERSYMIDX (DT_FLAGS_1)]->d_un.d_val & ~DF_1_NOW) == 0);
+  /* Flags must not be set for ld.so.  */
   assert (info[DT_FLAGS] == NULL
 	  || (info[DT_FLAGS]->d_un.d_val & ~DF_BIND_NOW) == 0);
-  /* Flags must not be set for ld.so.  */
+#endif
+#if defined RTLD_BOOTSTRAP || defined STATIC_PIE_BOOTSTRAP
   assert (info[DT_RUNPATH] == NULL);
   assert (info[DT_RPATH] == NULL);
 #else
diff --git a/manual/install.texi b/manual/install.texi
index 35948b1bbb..54df6abb97 100644
--- a/manual/install.texi
+++ b/manual/install.texi
@@ -136,6 +136,14 @@ Don't build shared libraries even if it is possible.  Not all systems
 support shared libraries; you need ELF support and (currently) the GNU
 linker.
 
+@item --enable-static-pie
+Build static executables, including tests, as position independent
+executable (static PIE) which is similar to static executable, but can
+be loaded at any address without help from a dynamic linker.  The
+resulting libc.a can be used with the GCC option, -static-pie, which
+is available with GCC 8 or above, to create static PIE.  Only i686, x86-64
+and x32 targets are verified to work.
+
 @item --disable-profile
 Don't build libraries with profiling information.  You may want to use
 this option if you don't plan to do profiling.
diff --git a/sysdeps/generic/ldsodefs.h b/sysdeps/generic/ldsodefs.h
index 1a4449eeb3..b4c032a06c 100644
--- a/sysdeps/generic/ldsodefs.h
+++ b/sysdeps/generic/ldsodefs.h
@@ -1048,6 +1048,13 @@ extern void _dl_determine_tlsoffset (void) attribute_hidden;
    stack protector, among other things).  */
 void __libc_setup_tls (void);
 
+# if ENABLE_STATIC_PIE
+/* Relocate static executable with PIE.  */
+void _dl_relocate_static_pie (void) attribute_hidden;
+# else
+#  define _dl_relocate_static_pie()
+# endif
+
 /* Initialization of libpthread for statically linked applications.
    If libpthread is not linked in, this is an empty function.  */
 void __pthread_initialize_minimal (void) weak_function;
diff --git a/sysdeps/x86_64/configure b/sysdeps/x86_64/configure
index efef46b1b7..8ee15b8a25 100644
--- a/sysdeps/x86_64/configure
+++ b/sysdeps/x86_64/configure
@@ -85,6 +85,39 @@ if test x"$build_mathvec" = xnotset; then
   build_mathvec=yes
 fi
 
+if test "$static_pie" = yes; then
+  { $as_echo "$as_me:${as_lineno-$LINENO}: checking for linker static PIE support" >&5
+$as_echo_n "checking for linker static PIE support... " >&6; }
+if ${libc_cv_ld_static_pie+:} false; then :
+  $as_echo_n "(cached) " >&6
+else
+  cat > conftest.s <<\EOF
+	.text
+	.global _start
+	.weak foo
+_start:
+	leaq	foo(%rip), %rax
+EOF
+  libc_cv_pie_option="-Wl,-pie"
+  if { ac_try='${CC-cc} $CFLAGS $CPPFLAGS $LDFLAGS -nostartfiles -nostdlib $no_ssp $libc_cv_pie_option conftest.s 1>&5'
+  { { eval echo "\"\$as_me\":${as_lineno-$LINENO}: \"$ac_try\""; } >&5
+  (eval $ac_try) 2>&5
+  ac_status=$?
+  $as_echo "$as_me:${as_lineno-$LINENO}: \$? = $ac_status" >&5
+  test $ac_status = 0; }; }; then
+    libc_cv_ld_static_pie=yes
+  else
+    libc_cv_ld_static_pie=no
+  fi
+rm -f conftest*
+fi
+{ $as_echo "$as_me:${as_lineno-$LINENO}: result: $libc_cv_ld_static_pie" >&5
+$as_echo "$libc_cv_ld_static_pie" >&6; }
+  if test "$libc_cv_ld_static_pie" != yes; then
+    as_fn_error $? "linker support for static PIE needed" "$LINENO" 5
+  fi
+fi
+
 $as_echo "#define PI_STATIC_AND_HIDDEN 1" >>confdefs.h
 
 
diff --git a/sysdeps/x86_64/configure.ac b/sysdeps/x86_64/configure.ac
index fa86e953ee..53e4a8277c 100644
--- a/sysdeps/x86_64/configure.ac
+++ b/sysdeps/x86_64/configure.ac
@@ -44,6 +44,31 @@ if test x"$build_mathvec" = xnotset; then
   build_mathvec=yes
 fi
 
+dnl Check if linker supports static PIE with the fix for
+dnl
+dnl https://sourceware.org/bugzilla/show_bug.cgi?id=21782
+dnl
+if test "$static_pie" = yes; then
+  AC_CACHE_CHECK(for linker static PIE support, libc_cv_ld_static_pie, [dnl
+cat > conftest.s <<\EOF
+	.text
+	.global _start
+	.weak foo
+_start:
+	leaq	foo(%rip), %rax
+EOF
+  libc_cv_pie_option="-Wl,-pie"
+  if AC_TRY_COMMAND(${CC-cc} $CFLAGS $CPPFLAGS $LDFLAGS -nostartfiles -nostdlib $no_ssp $libc_cv_pie_option conftest.s 1>&AS_MESSAGE_LOG_FD); then
+    libc_cv_ld_static_pie=yes
+  else
+    libc_cv_ld_static_pie=no
+  fi
+rm -f conftest*])
+  if test "$libc_cv_ld_static_pie" != yes; then
+    AC_MSG_ERROR([linker support for static PIE needed])
+  fi
+fi
+
 dnl It is always possible to access static and hidden symbols in an
 dnl position independent way.
 AC_DEFINE(PI_STATIC_AND_HIDDEN)
-- 
2.13.6


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