This commit removes the ELF constructor and internal variables from
dlfcn/dlfcn.c. The file now serves the same purpose as
nptl/libpthread-compat.c, so it is renamed to dlfcn/libdl-compat.c.
The use of libdl-shared-only-routines ensures that libdl.a is empty.
This commit adjusts the test suite not to use $(libdl). The libdl.so
symbolic link is no longer installed.
Reviewed-by: Adhemerval Zanella <adhemerval.zanella@linaro.org>
Since the variable expands to nothing under Linux, it is no longer
necessary to clutter the makefiles with it.
Reviewed-by: Adhemerval Zanella <adhemerval.zanella@linaro.org>
Only the placeholder compatibility symbols are left now.
The __errno_location symbol was removed (moved) using
scripts/move-symbol-to-libc.py.
Reviewed-by: Adhemerval Zanella <adhemerval.zanella@linaro.org>
This bumps the highest valid EI_ABIVERSION value to ABSOLUTE ABI.
New testcase loads the symbol from the GOT with the "lb" instruction
so that the EI_ABIVERSION header field of the shared object is set
to ABSOLUTE (it doesn't actually check the value of the symbol), and
makes sure that the main executable is executed without "ABI version
invalid" error.
Tested for all three ABIs (o32, n32, n64) using both static linker which
handles undefined weak symbols correctly [1] (and sets the EI_ABIVERSION
of the test module) and the one that doesn't (EI_ABIVERSION left as 0).
[1] https://sourceware.org/ml/binutils/2018-07/msg00268.html
[BZ #24916]
* sysdeps/mips/Makefile [$(subdir) = elf] (tests): Add
tst-undefined-weak.
[$(subdir) = elf] (modules-names): Add tst-undefined-weak-lib.
[$(subdir) = elf] ($(objpfx)tst-undefined-weak): Add dependency.
* sysdeps/mips/tst-undefined-weak-lib.S: New file.
* sysdeps/mips/tst-undefined-weak.c: Likewise.
* sysdeps/unix/sysv/linux/mips/ldsodefs.h (VALID_ELF_ABIVERSION):
Increment highest valid ABIVERSION value.
Static PIE extends address space layout randomization to static
executables. It provides additional security hardening benefits at
the cost of some memory and performance.
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. Only GCC
with PIE support is needed. 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 not allowed
in static PIE.
The following changes are made for static PIE:
1. Add a new function, _dl_relocate_static_pie, to:
a. Get the run-time load address.
b. Read the dynamic section.
c. Perform dynamic relocations.
Dynamic linker also performs these steps. But static PIE doesn't load
any shared objects.
2. Call _dl_relocate_static_pie at entrance of LIBC_START_MAIN in
libc.a. crt1.o, which is used to create dynamic and non-PIE static
executables, is updated to include a dummy _dl_relocate_static_pie.
rcrt1.o is added to create static PIE, which will link in the real
_dl_relocate_static_pie. grcrt1.o is also added to create static PIE
with -pg. GCC 8 has been updated to support rcrt1.o and grcrt1.o for
static PIE.
Static PIE can work on all architectures which support PIE, provided:
1. Target must support accessing of local functions without dynamic
relocations, which is needed in start.S to call __libc_start_main with
function addresses of __libc_csu_init, __libc_csu_fini and main. All
functions in static PIE are local functions. If PIE start.S can't reach
main () defined in a shared object, the code sequence:
pass address of local_main to __libc_start_main
...
local_main:
tail call to main via PLT
can be used.
2. 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.
3. All assembly codes are updated check PIC instead SHARED for PIC code
path to avoid dynamic relocations in read-only sections.
4. All assembly codes are updated check SHARED instead PIC for static
symbol name.
5. elf_machine_load_address in dl-machine.h are updated to support static
PIE.
6. __brk works without TLS nor dynamic relocations in read-only section
so that it can be used by __libc_setup_tls to initializes TLS in static
PIE.
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 whether 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.
On x86-64, the normal static sln:
text data bss dec hex filename
625425 8284 5456 639165 9c0bd elf/sln
the static PIE sln:
text data bss dec hex filename
657626 20636 5392 683654 a6e86 elf/sln
The code size is increased by 5% and the binary size is increased by 7%.
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
The i386 linker needs to be able to convert "movl main@GOT(%ebx), %eax"
to "leal main@GOTOFF(%ebx), %eax" if main is defined locally.
Binutils 2.29 or above are OK for i686 and x86-64. But linker status for
other targets need to be verified.
3. Linker should resolve undefined weak symbols to 0 in static PIE:
https://sourceware.org/bugzilla/show_bug.cgi?id=22269
4. Many ELF backend linkers incorrectly check bfd_link_pic for TLS
relocations, which should check bfd_link_executable instead:
https://sourceware.org/bugzilla/show_bug.cgi?id=22263
Tested on aarch64, i686 and x86-64.
Using GCC 7 and binutils master branch, build-many-glibcs.py with
--enable-static-pie with all patches for static PIE applied have the
following build successes:
PASS: glibcs-aarch64_be-linux-gnu build
PASS: glibcs-aarch64-linux-gnu build
PASS: glibcs-armeb-linux-gnueabi-be8 build
PASS: glibcs-armeb-linux-gnueabi build
PASS: glibcs-armeb-linux-gnueabihf-be8 build
PASS: glibcs-armeb-linux-gnueabihf build
PASS: glibcs-arm-linux-gnueabi build
PASS: glibcs-arm-linux-gnueabihf build
PASS: glibcs-arm-linux-gnueabihf-v7a build
PASS: glibcs-arm-linux-gnueabihf-v7a-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-n32 build
PASS: glibcs-mips64el-linux-gnu-n32-nan2008 build
PASS: glibcs-mips64el-linux-gnu-n32-nan2008-soft build
PASS: glibcs-mips64el-linux-gnu-n32-soft 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-n32 build
PASS: glibcs-mips64-linux-gnu-n32-nan2008 build
PASS: glibcs-mips64-linux-gnu-n32-nan2008-soft build
PASS: glibcs-mips64-linux-gnu-n32-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-mipsel-linux-gnu build
PASS: glibcs-mipsel-linux-gnu-nan2008 build
PASS: glibcs-mipsel-linux-gnu-nan2008-soft build
PASS: glibcs-mipsel-linux-gnu-soft build
PASS: glibcs-mips-linux-gnu build
PASS: glibcs-mips-linux-gnu-nan2008 build
PASS: glibcs-mips-linux-gnu-nan2008-soft build
PASS: glibcs-mips-linux-gnu-soft build
PASS: glibcs-nios2-linux-gnu build
PASS: glibcs-powerpc64le-linux-gnu build
PASS: glibcs-powerpc64-linux-gnu build
PASS: glibcs-tilegxbe-linux-gnu-32 build
PASS: glibcs-tilegxbe-linux-gnu build
PASS: glibcs-tilegx-linux-gnu-32 build
PASS: glibcs-tilegx-linux-gnu build
PASS: glibcs-tilepro-linux-gnu build
and the following build failures:
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-hppa-linux-gnu build
elf/sln is failed to link due to:
collect2: fatal error: ld terminated with signal 11 [Segmentation fault]
https://sourceware.org/bugzilla/show_bug.cgi?id=22537
FAIL: glibcs-ia64-linux-gnu build
elf/sln is failed to link due to:
collect2: fatal error: ld terminated with signal 11 [Segmentation fault]
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. See:
https://sourceware.org/bugzilla/show_bug.cgi?id=22264
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:14299
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. See:
https://sourceware.org/bugzilla/show_bug.cgi?id=22263
Also TLS code sequence in SH assembly syscalls in glibc doesn't match TLS
code sequence expected by ld:
https://sourceware.org/bugzilla/show_bug.cgi?id=22270
FAIL: glibcs-sparc64-linux-gnu build
FAIL: glibcs-sparcv9-linux-gnu build
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. See:
https://sourceware.org/bugzilla/show_bug.cgi?id=22263
[BZ #19574]
* INSTALL: Regenerated.
* Makeconfig (real-static-start-installed-name): New.
(pic-default): Updated for --enable-static-pie.
(pie-default): New for --enable-static-pie.
(default-pie-ldflag): Likewise.
(+link-static-before-libc): Replace $(DEFAULT-LDFLAGS-$(@F))
with $(if $($(@F)-no-pie),$(no-pie-ldflag),$(default-pie-ldflag)).
Replace $(static-start-installed-name) with
$(real-static-start-installed-name).
(+prectorT): Updated for --enable-static-pie.
(+postctorT): Likewise.
(CFLAGS-.o): Add $(pie-default).
(CFLAGS-.op): Likewise.
* NEWS: Mention --enable-static-pie.
* config.h.in (ENABLE_STATIC_PIE): New.
* configure.ac (--enable-static-pie): New configure option.
(have-no-dynamic-linker): New LIBC_CONFIG_VAR.
(have-static-pie): Likewise.
Enable static PIE if linker supports --no-dynamic-linker.
(ENABLE_STATIC_PIE): New AC_DEFINE.
(enable-static-pie): New LIBC_CONFIG_VAR.
* configure: Regenerated.
* csu/Makefile (omit-deps): Add r$(start-installed-name) and
gr$(start-installed-name) for --enable-static-pie.
(extra-objs): Likewise.
(install-lib): Likewise.
(extra-objs): Add static-reloc.o and static-reloc.os
($(objpfx)$(start-installed-name)): Also depend on
$(objpfx)static-reloc.o.
($(objpfx)r$(start-installed-name)): New.
($(objpfx)g$(start-installed-name)): Also depend on
$(objpfx)static-reloc.os.
($(objpfx)gr$(start-installed-name)): New.
* csu/libc-start.c (LIBC_START_MAIN): Call _dl_relocate_static_pie
in libc.a.
* csu/libc-tls.c (__libc_setup_tls): Add main_map->l_addr to
initimage.
* csu/static-reloc.c: New file.
* elf/Makefile (routines): Add dl-reloc-static-pie.
(elide-routines.os): Likewise.
(DEFAULT-LDFLAGS-tst-tls1-static-non-pie): Removed.
(tst-tls1-static-non-pie-no-pie): New.
* elf/dl-reloc-static-pie.c: New file.
* elf/dl-support.c (_dl_get_dl_main_map): New function.
* elf/dynamic-link.h (ELF_DURING_STARTUP): Also check
STATIC_PIE_BOOTSTRAP.
* elf/get-dynamic-info.h (elf_get_dynamic_info): Likewise.
* gmon/Makefile (tests): Add tst-gmon-static-pie.
(tests-static): Likewise.
(DEFAULT-LDFLAGS-tst-gmon-static): Removed.
(tst-gmon-static-no-pie): New.
(CFLAGS-tst-gmon-static-pie.c): Likewise.
(CRT-tst-gmon-static-pie): Likewise.
(tst-gmon-static-pie-ENV): Likewise.
(tests-special): Likewise.
($(objpfx)tst-gmon-static-pie.out): Likewise.
(clean-tst-gmon-static-pie-data): Likewise.
($(objpfx)tst-gmon-static-pie-gprof.out): Likewise.
* gmon/tst-gmon-static-pie.c: New file.
* manual/install.texi: Document --enable-static-pie.
* sysdeps/generic/ldsodefs.h (_dl_relocate_static_pie): New.
(_dl_get_dl_main_map): Likewise.
* sysdeps/i386/configure.ac: Check if linker supports static PIE.
* sysdeps/x86_64/configure.ac: Likewise.
* sysdeps/i386/configure: Regenerated.
* sysdeps/x86_64/configure: Likewise.
* sysdeps/mips/Makefile (ASFLAGS-.o): Add $(pie-default).
(ASFLAGS-.op): Likewise.
Add unwind info to __libc_start_main so that unwinding continues one
extra level to _start. Similarly add unwind info to backtrace.
Given many targets require this, do this in a general way.
* csu/Makefile: Add -funwind-tables to libc-start.c.
* debug/Makefile: Add -funwind-tables to backtrace.c.
* sysdeps/aarch64/Makefile: Remove CFLAGS-backtrace.c.
* sysdeps/arm/Makefile: Likewise.
* sysdeps/i386/Makefile: Likewise.
* sysdeps/m68k/Makefile: Likewise.
* sysdeps/mips/Makefile: Likewise.
* sysdeps/nios2/Makefile: Likewise.
* sysdeps/sh/Makefile: Likewise.
* sysdeps/sparc/Makefile: Likewise.
On MIPS when the toolchain is using the O32 FPXX ABI, the testsuite
fails to build for pre-R2 CPU.
It assumes that it is possible to use the -mfp64 option to build
tst-abi-fp64amod and tst-abi-fp64mod, while this requires a CPU which
supports the mfhc1 and mthc1 instructions, ie at least a R2 CPU:
error: '-mgp32' and '-mfp64' can only be combined if the target
supports the mfhc1 and mthc1 instructions
The same way it assumes that it is possible to use the -modd-spreg option
to build tst-abi-fpxxomod and tst-abi-fp64mod, while this requires at
least a R1 CPU:
warning: the 'mips2' architecture does not support odd
single-precision registers
This patches changes that by checking the usability of -mfp64 and
-modd-spreg options in configure, and disable those tests when they can
not be used.
I've moved the MIPS port from ports to the main sysdeps hierarchy.
Beyond the README update, the move of the files was simply
git mv ports/sysdeps/mips sysdeps/mips
git mv ports/sysdeps/unix/mips sysdeps/unix/mips
git mv ports/sysdeps/unix/sysv/linux/mips sysdeps/unix/sysv/linux/mips
and in addition to the ChangeLog entries here, I put a note at the top
of ports/ChangeLog.mips similar to those in other files.
Tested that disassembly of installed shared libraries for mips is the
same before and after this patch (except for ld.so where paths in
assertions are involved, as for arm).
* sysdeps/mips: Move directory from ports/sysdeps/mips.
* sysdeps/unix/mips: Move directory from ports/sysdeps/unix/mips.
* sysdeps/unix/sysv/linux/mips: Move directory from
ports/sysdeps/unix/sysv/linux/mips.
* README: Update listing for mips-*-linux-gnu and
mips64-*-linux-gnu.
* sysdeps/mips: Move directory to ../sysdeps/mips.
* sysdeps/unix/mips: Move directory to ../sysdeps/unix/mips.
* sysdeps/unix/sysv/linux/mips: Move directory to
../sysdeps/unix/sysv/linux/mips.
1998-11-27 Philip Blundell <pb@nexus.co.uk>
Fixes to allow compilation with static NSS:
* nss/Makefile: Make explicit the dependency of getent on
libnss_files.a.
[build_static_nss]: Define $(otherlibs) appropriately.
* nss/Depend: Add a dependency on `resolv'.
1998-11-27 Andreas Jaeger <aj@arthur.rhein-neckar.de>
Partial support for MIPS ISO C 9x exception handling:
* sysdeps/mips/fclrexcpt.c: New file.
* sysdeps/mips/ftestexcept.c: New file.
* sysdeps/mips/fgetexcptflg.c: New file.
* sysdeps/mips/fesetround.c: New file.
* sysdeps/mips/fegetround.c: New file.
* sysdeps/mips/fegetenv.c: New file.
* sysdeps/mips/fesetenv.c: New file.
* sysdeps/mips/feupdateenv.c: Likewise.
* sysdeps/mips/bits/fenv.h: New file.
1998-11-28 Andreas Jaeger <aj@arthur.rhein-neckar.de>
* sysdeps/unix/sysv/linux/mips/bits/signum.h: Remove inclusion of
<asm/signal.h> and add needed symbols from <asm/signal.h>; bring
in sync with linux specific version.
Patches by Ralf Baechle <ralf@uni-koblenz.de> for mips-linux:
* sysdeps/unix/mips/sysdep.S: Define _errno as weak_alias, rewrite
errno declaration.
* sysdeps/unix/sysv/linux/mips/ustat.c: Use INLINE_SYSCALL instead
of calling __syscall_*.
* sysdeps/unix/sysv/linux/mips/xmknod.c: Likewise.
* sysdeps/unix/sysv/linux/mips/syscalls.list: Update entries.
* sysdeps/unix/sysv/linux/mips/sys/syscall.h: Add missing SYS_*
constants, correct values according to Linux 2.1.130.
* sysdeps/unix/sysv/linux/mips/pwrite.c: New file.
* sysdeps/unix/sysv/linux/mips/pwrite64.c: New file.
* sysdeps/unix/sysv/linux/mips/pread.c: New file.
* sysdeps/unix/sysv/linux/mips/pread64.c: New file.
* sysdeps/mips/Makefile (sysdep_routines): Use += instead of a
:=.
* sysdeps/unix/sysv/linux/mips/bits/ipc.h: Remove ipc_kludge.
* sysdeps/unix/sysv/linux/mips/xstatconv.c: New file.
* sysdeps/unix/sysv/linux/mips/xstat.c: Removed.
* sysdeps/unix/sysv/linux/mips/sys/ucontext.h: New file.
* sysdeps/unix/sysv/linux/mips/kernel_termios.h: Add copyright
message, change name of include protection, remove inclusion of
<bits/termios.h>.
* sysdeps/unix/sysv/linux/mips/kernel_sigaction.h
(old_kernel_sigaction): Define.
(struct kernel_sigaction): Rename sa_handler to k_sa_handler.
* sysdeps/unix/sysv/linux/mips/bits/time.h: Removed, we can use
the general linux version.
* sysdeps/unix/sysv/linux/mips/bits/stat.h (_STAT_VER_KERNEL): Added.
* sysdeps/unix/sysv/linux/mips/bits/socket.h: Update file.
1998-09-03 Philip Blundell <pb@nexus.co.uk>
* sysdeps/arm/bits/endian.h (__FLOAT_WORD_ORDER): Define to big
endian.
* math/math_private.h: Use __FLOAT_WORD_ORDER rather than
BYTE_ORDER.
* string/endian.h: If __FLOAT_WORD_ORDER wasn't defined by
<bits/endian.h>, make it the same as __BYTE_ORDER.
1998-11-26 Andreas Schwab <schwab@issan.cs.uni-dortmund.de>
* Makeconfig ($(common-objpfx)sysd-dirs): Use automatic variables
if possible.
($(common-objpfx)sysd-sorted): Likewise.
1998-11-27 Andreas Jaeger <aj@arthur.rhein-neckar.de>
* sysdeps/libm-ieee754/e_log.c (__ieee754_log): Add declaration of
local variables t1,t2 only if needed.
* sysdeps/libm-ieee754/s_truncf.c (__truncf): Likewise.
* sysdeps/libm-ieee754/s_trunc.c (__trunc): Likewise.
* sysdeps/mips/mul_1.S (Loop): Add closing comment to avoid
warning.
1998-11-27 Andreas Jaeger <aj@arthur.rhein-neckar.de>
* math/math.h: Add brace to correct #if expression.
1998-11-26 Philip Blundell <philb@gnu.org>
Undo change of 1998-11-12:
* sysdeps/unix/sysv/linux/netlink/netlink.h: Deleted.
* sysdeps/unix/sysv/linux/Makefile (sysdep_headers): Remove
netlink/netlink.h.
* sysdeps/unix/sysv/linux/Dist: Likewise.
1998-11-22 Thorsten Kukuk <kukuk@vt.uni-paderborn.de>
* nis/nis_print.c (nis_print_entry): Changes to match Solaris output.
1998-11-26 Andreas Jaeger <aj@arthur.rhein-neckar.de>
* sysdeps/generic/pselect.c (__pselect): Change interface,
set/restore sigmask.
* misc/sys/select.h: Change declaration according to Stevens' Unix
Network Programming.
* include/sys/select.h (__pselect): Likewise.
Reported by <bwelling@anomaly.munge.com> [PR libc/872].
* include/fpu_control.h: New file, contains __setfpucw
declaration.
* sysdeps/generic/fpu_control.h: Remove __setfpucw declaration,
it's an internal symbol.
* sysdeps/alpha/fpu/fpu_control.h: Likewise.
* sysdeps/arm/fpu/fpu_control.h: Likewise.
* sysdeps/i386/fpu_control.h: Likewise.
* sysdeps/m68k/fpu_control.h: Likewise.
* sysdeps/powerpc/fpu_control.h: Likewise.
* sysdeps/sparc/sparc32/fpu/fpu_control.h: Likewise.
* sysdeps/sparc/sparc64/fpu/fpu_control.h: Likewise.
