On Linux/i386, there are 3 ways to make a system call:
1. call *%gs:SYSINFO_OFFSET. This requires TLS initialization.
2. call *_dl_sysinfo. This requires relocation of _dl_sysinfo.
3. int $0x80. This is slower than #2 and #3, but works everywhere.
When an object file is compiled with PIC, #1 is prefered since it is
faster than #3 and doesn't require relocation of _dl_sysinfo. For
dynamic executables, ld.so initializes TLS. However, for static
executables, before TLS is initialized by __libc_setup_tls, #3 should
be used for system calls.
This patch adds <startup.h> which defines _startup_fatal and defaults
it to __libc_fatal. It replaces __libc_fatal with _startup_fatal in
static executables where it is called before __libc_setup_tls is called.
This header file is included in all files containing functions which are
called before __libc_setup_tls is called. On Linux/i386, when PIE is
enabled by default, _startup_fatal is turned into ABORT_INSTRUCTION and
I386_USE_SYSENTER is defined to 0 so that "int $0x80" is used for system
calls before __libc_setup_tls is called.
Tested on i686 and x86-64. Without this patch, all statically-linked
tests will fail on i686 when the compiler defaults to -fPIE.
[BZ #21913]
* csu/libc-tls.c: Include <startup.h> first.
(__libc_setup_tls): Call _startup_fatal instead of __libc_fatal.
* elf/dl-tunables.c: Include <startup.h> first.
* include/libc-symbols.h (BUILD_PIE_DEFAULT): New.
* sysdeps/generic/startup.h: New file.
* sysdeps/unix/sysv/linux/i386/startup.h: Likewise.
* sysdeps/unix/sysv/linux/i386/brk.c [BUILD_PIE_DEFAULT != 0]
(I386_USE_SYSENTER): New. Defined to 0.
Different than other architectures hppa-linux-gnu define different values
for ENOTSUP and EOPNOTSUPP, where the later is a Linux specific one.
This leads to tst-preadwritev{64}v2 tests failures:
$ ./testrun.sh misc/tst-preadvwritev2
error: tst-preadvwritev2-common.c:35: preadv2 failure did not set errno to ENOTSUP (223)
error: 1 test failures
The straightforward fix is to return the POSIX defined ENOTSUP on all
p{read,write}v{64}v2 implementations instead of Linux specific one.
Checked on x86_64-linux-gnu and the tst-preadwritev{64}v2 on
hppa-linux-gnu (although due the installed kernel on my testing system
the pwritev{64}v2 with an invalid flag still fails due a known kernel
issue [1]).
[BZ #21780]
* sysdeps/posix/preadv2.c (preadv2): Use ENOTSUP instead of
EOPNOTSUPP.
* sysdeps/posix/preadv64v2.c (preadv64v2): Likewise.
* sysdeps/posix/pwritev2.c (pwritev2): Likewise.
* sysdeps/posix/pwritev64v2.c (pwritev64v2): Likewise.
* sysdeps/unix/sysv/linux/preadv2.c (preadv2): Likewise.
* sysdeps/unix/sysv/linux/preadv64v2.c (preadv64v2): Likewise.
* sysdeps/unix/sysv/linux/pwritev2.c (pwritev2): Likewise.
* sysdeps/unix/sysv/linux/pwritev64v2.c (pwritev64v2): Likewise.
[1] https://sourceware.org/ml/libc-alpha/2017-06/msg00726.html
For XPG4.2, sa_sigaction, SA_ONSTACK, SA_RESETHAND, SA_RESTART and
SA_NODEFER should be defined in signal.h, but they are only defined
for other standards at present.
This patch fixes the various bits/sigaction.h headers accordingly.
All the fixes are essentially the same, except those for SPARC and
Tile.
For SPARC, the header (a) spuriously defined various nonstandard
macros for __USE_UNIX98 || defined __USE_XOPEN2K8 and (b) defined some
standard macros as aliases of nonstandard ones instead of the other
way round. This patch fixes the SPARC header to handle these macros
the same way and with the same conditions as those for other
architectures, so the standard macros are the primary ones and the
other ones are defined only for __USE_MISC and are aliases of the
standard ones where applicable.
For Tile, the header spuriously defined the nonstandard macro
SA_NOPTRACE for __USE_UNIX98 || defined __USE_XOPEN2K8; this is moved
to __USE_MISC.
(Those nonstandard macros are in a reserved namespace, but it seems
desirable to be consistent between architectures as far as possible,
and so not define them in standard modes anywhere.)
Tested for x86_64, and with build-many-glibcs.py.
[BZ #21899]
* bits/sigaction.h (struct sigaction): Define sa_handler and
sa_sigaction using union also for [__USE_XOPEN_EXTENDED].
(SA_ONSTACK): Change [__USE_UNIX98] condition to
[__USE_XOPEN_EXTENDED].
(SA_RESTART): Likewise.
(SA_NODEFER): Likewise.
(SA_RESETHAND): Likewise.
* sysdeps/unix/sysv/linux/alpha/bits/sigaction.h
(struct sigaction): Define sa_handler and sa_sigaction using union
also for [__USE_XOPEN_EXTENDED].
(SA_ONSTACK): Change [__USE_UNIX98] condition to
[__USE_XOPEN_EXTENDED].
(SA_RESTART): Likewise.
(SA_NODEFER): Likewise.
(SA_RESETHAND): Likewise.
* sysdeps/unix/sysv/linux/bits/sigaction.h
(struct sigaction): Define sa_handler and sa_sigaction using union
also for [__USE_XOPEN_EXTENDED].
(SA_ONSTACK): Change [__USE_UNIX98] condition to
[__USE_XOPEN_EXTENDED].
(SA_RESTART): Likewise.
(SA_NODEFER): Likewise.
(SA_RESETHAND): Likewise.
* sysdeps/unix/sysv/linux/hppa/bits/sigaction.h
(struct sigaction): Define sa_handler and sa_sigaction using union
also for [__USE_XOPEN_EXTENDED].
(SA_ONSTACK): Change [__USE_UNIX98] condition to
[__USE_XOPEN_EXTENDED].
(SA_RESTART): Likewise.
(SA_NODEFER): Likewise.
(SA_RESETHAND): Likewise.
* sysdeps/unix/sysv/linux/ia64/bits/sigaction.h
(struct sigaction): Define sa_handler and sa_sigaction using union
also for [__USE_XOPEN_EXTENDED].
(SA_ONSTACK): Change [__USE_UNIX98] condition to
[__USE_XOPEN_EXTENDED].
(SA_RESTART): Likewise.
(SA_NODEFER): Likewise.
(SA_RESETHAND): Likewise.
* sysdeps/unix/sysv/linux/mips/bits/sigaction.h
(struct sigaction): Define sa_handler and sa_sigaction using union
also for [__USE_XOPEN_EXTENDED].
(SA_ONSTACK): Change [__USE_UNIX98] condition to
[__USE_XOPEN_EXTENDED].
(SA_RESTART): Likewise.
(SA_NODEFER): Likewise.
(SA_RESETHAND): Likewise.
* sysdeps/unix/sysv/linux/s390/bits/sigaction.h
(struct sigaction): Define sa_handler and sa_sigaction using union
also for [__USE_XOPEN_EXTENDED].
(SA_ONSTACK): Change [__USE_UNIX98] condition to
[__USE_XOPEN_EXTENDED].
(SA_RESTART): Likewise.
(SA_NODEFER): Likewise.
(SA_RESETHAND): Likewise.
* sysdeps/unix/sysv/linux/sparc/bits/sigaction.h
(struct sigaction): Define sa_handler and sa_sigaction using union
also for [__USE_XOPEN_EXTENDED].
(SA_ONSTACK): Change [__USE_UNIX98] condition to
[__USE_XOPEN_EXTENDED].
(SA_RESTART): Likewise.
(SA_NODEFER): Likewise. Define directly rather than as alias.
(SA_RESETHAND): Likewise.
(SA_INTERRUPT): Define only for [__USE_MISC].
(SA_NOMASK): Define as alias of SA_NODEFER, only for [__USE_MISC].
(SA_ONESHOT): Define as alias of SA_RESETHAND, only for
[__USE_MISC].
(SA_STACK): Define only for [__USE_MISC].
* sysdeps/unix/sysv/linux/tile/bits/sigaction.h
(struct sigaction): Define sa_handler and sa_sigaction using union
also for [__USE_XOPEN_EXTENDED].
(SA_ONSTACK): Change [__USE_UNIX98] condition to
[__USE_XOPEN_EXTENDED].
(SA_RESTART): Likewise.
(SA_NODEFER): Likewise.
(SA_RESETHAND): Likewise.
(SA_NOPTRACE): Define only for [__USE_MISC].
This patch reimplements the libm-internal min_of_type macro to use
__MATH_TG instead of its own local type-generic implementation, so
simplifying the code and reducing the number of different type-generic
implementation variants in use in glibc.
Tested for x86_64.
* sysdeps/generic/math_private.h (__EXPR_FLT128): Remove macro.
(min_of_type_f): New macro.
(min_of_type_): Likewise.
(min_of_type_l): Likewise.
(min_of_type_f128): Likewise.
(min_of_type): Define using __MATH_TG and taking an expression
argument.
(math_check_force_underflow): Pass expression instead of type to
min_of_type.
(math_check_force_underflow_nonneg): Likewise.
Since all x86 IFUNC selectors are implemented in C, assembly versions of
HAS_CPU_FEATURE and HAS_ARCH_FEATURE can be removed.
* sysdeps/x86/cpu-features.h [__ASSEMBLER__]
(LOAD_RTLD_GLOBAL_RO_RDX, HAS_FEATURE, LOAD_FUNC_GOT_EAX,
HAS_CPU_FEATURE, HAS_ARCH_FEATURE): Removed.
Since start.o may be compiled as PIC, we should check PIC instead of
SHARED. Also avoid dynamic relocation against main in static PIE since
_start is the entry point before the executable is relocated.
* sysdeps/i386/start.S (_start): Check Check PIC instead of
SHARED. Avoid dynamic relocation against main in static PIE.
Define I386_USE_SYSENTER to 0 or 1 so that special versions of syscalls
with "int $0x80" can be provided for static PIE during self relocation.
Also check PIC instead SHARED for PIC version of syscall macros.
* sysdeps/unix/sysv/linux/i386/sysdep.h (I386_USE_SYSENTER):
Define to I386_USE_SYSENTER to 0 or 1 if not defined.
(ENTER_KERNEL): Check if I386_USE_SYSENTER is 1 and check PIC.
(INTERNAL_SYSCALL_MAIN_INLINE): Likewise.
(INTERNAL_SYSCALL_NCS): Likewise.
(LOADARGS_1): Likewise.
(LOADARGS_5): Likewise.
(RESTOREARGS_1): Likewise.
(RESTOREARGS_5): Likewise.
Since apply_irel is called before memcpy and mempcpy are called, we
can use IFUNC memcpy and mempcpy in libc.a.
* sysdeps/x86_64/memmove.S (MEMCPY_SYMBOL): Don't check SHARED.
(MEMPCPY_SYMBOL): Likewise.
* sysdeps/x86_64/multiarch/ifunc-impl-list.c
(__libc_ifunc_impl_list): Test memcpy and mempcpy in libc.a.
* sysdeps/x86_64/multiarch/memcpy-ssse3-back.S: Also include
in libc.a.
* sysdeps/x86_64/multiarch/memcpy-ssse3.S: Likewise.
* sysdeps/x86_64/multiarch/memmove-avx512-no-vzeroupper.S:
Likewise.
* sysdeps/x86_64/multiarch/memcpy.c: Also include in libc.a.
(__hidden_ver1): Don't use in libc.a.
* sysdeps/x86_64/multiarch/memmove-sse2-unaligned-erms.S
(__mempcpy): Don't create a weak alias in libc.a.
* sysdeps/x86_64/multiarch/memmove-vec-unaligned-erms.S: Support
libc.a.
* sysdeps/x86_64/multiarch/mempcpy.c: Also include in libc.a.
(__hidden_ver1): Don't use in libc.a.
Since gold doesn't support INSERT in linker script:
https://sourceware.org/bugzilla/show_bug.cgi?id=21676
tst-split-dynreloc fails to link with gold. Check if linker supports
INSERT in linker script before using it.
* config.make.in (have-insert): New.
* configure.ac (libc_cv_insert): New. Set to yes if linker
supports INSERT in linker script.
(AC_SUBST(libc_cv_insert): New.
* configure: Regenerated.
* sysdeps/x86_64/Makefile (tests): Add tst-split-dynreloc only
if $(have-insert) == yes.
On AVX machines with XGETBV (ECX == 1) like Skylake processors,
(gdb) disass _dl_runtime_resolve_avx_opt
Dump of assembler code for function _dl_runtime_resolve_avx_opt:
0x0000000000015890 <+0>: push %rax
0x0000000000015891 <+1>: push %rcx
0x0000000000015892 <+2>: push %rdx
0x0000000000015893 <+3>: mov $0x1,%ecx
0x0000000000015898 <+8>: xgetbv
0x000000000001589b <+11>: mov %eax,%r11d
0x000000000001589e <+14>: pop %rdx
0x000000000001589f <+15>: pop %rcx
0x00000000000158a0 <+16>: pop %rax
0x00000000000158a1 <+17>: and $0x4,%r11d
0x00000000000158a5 <+21>: bnd je 0x16200 <_dl_runtime_resolve_sse_vex>
End of assembler dump.
is slower than:
(gdb) disass _dl_runtime_resolve_avx_slow
Dump of assembler code for function _dl_runtime_resolve_avx_slow:
0x0000000000015850 <+0>: vorpd %ymm0,%ymm1,%ymm8
0x0000000000015854 <+4>: vorpd %ymm2,%ymm3,%ymm9
0x0000000000015858 <+8>: vorpd %ymm4,%ymm5,%ymm10
0x000000000001585c <+12>: vorpd %ymm6,%ymm7,%ymm11
0x0000000000015860 <+16>: vorpd %ymm8,%ymm9,%ymm9
0x0000000000015865 <+21>: vorpd %ymm10,%ymm11,%ymm10
0x000000000001586a <+26>: vpcmpeqd %xmm8,%xmm8,%xmm8
0x000000000001586f <+31>: vorpd %ymm9,%ymm10,%ymm10
0x0000000000015874 <+36>: vptest %ymm10,%ymm8
0x0000000000015879 <+41>: bnd jae 0x158b0 <_dl_runtime_resolve_avx>
0x000000000001587c <+44>: vzeroupper
0x000000000001587f <+47>: bnd jmpq 0x16200 <_dl_runtime_resolve_sse_vex>
End of assembler dump.
(gdb)
since xgetbv takes much more cycles than single cycle operations like
vpord/vvpcmpeq/ptest. _dl_runtime_resolve_opt should be used only with
AVX512 where AVX512 instructions lead to lower CPU frequency on Skylake
server.
[BZ #21871]
* sysdeps/x86/cpu-features.c (init_cpu_features): Set
bit_arch_Use_dl_runtime_resolve_opt only with AVX512F.
__memset_zero_constant_len_parameter should be removed by
commit 61062f5630
Author: Ulrich Drepper <drepper@redhat.com>
Date: Tue Mar 1 00:35:23 2005 +0000
2005-02-24 Roland McGrath <roland@redhat.com>
* debug/Versions (libc: GLIBC_2.4): Remove
__memset_zero_constant_len_parameter.
* sysdeps/generic/memset_chk.c: Remove alias and warning.
* misc/sys/cdefs.h (__warndecl): New macro.
* debug/warning-nop.c: New file.
* string/bits/string3.h (memset): Call __warn_memset_zero_len with no
arguments, instead of calling __memset_zero_constant_len_parameter.
Use __warndecl for __warn_memset_zero_len.
* debug/Makefile (routines): Add $(static-only-routines).
(static-only-routines): New variable.
This patch removes the last emaining pieces of it. Tested it on i586,
i686 and x86-64.
[BZ #21790]
* sysdeps/i386/i586/memset.S
(__memset_zero_constant_len_parameter): Removed.
* sysdeps/i386/i686/memset.S
(__memset_zero_constant_len_parameter): Likewise.
* sysdeps/i386/i686/multiarch/memset_chk.S
(__memset_zero_constant_len_parameter): Likewise.
* sysdeps/x86_64/memset.S (__memset_zero_constant_len_parameter):
Likewise.
This makes the __tls_get_addr_opt test run as a shared library, and so
actually test that DTPMOD64/DTPREL64 pairs are processed by ld.so to
support the __tls_get_adfr_opt call stub fast return. After a
2017-01-24 patch (binutils f0158f4416) ld.bfd no longer emitted
unnecessary dynamic relocations against local thread variables,
instead setting up the __tls_index GOT entries for the call stub fast
return. This meant tst-tlsopt-powerpc passed but did not check ld.so
relocation support. After a 2017-07-16 patch (binutils 676ee2b5fa)
ld.bfd no longer set up the __tls_index GOT entries for the call stub
fast return, and tst-tlsopt-powerpc failed.
Compiling mod-tlsopt-powerpc.c with -DSHARED exposed a bug in
powerpc64/tls-macros.h, which defines a __TLS_GET_ADDR macro that
clashes with one defined in dl-tls.h. The tls-macros.h version is
only used in that file, so delete it and expand.
* sysdeps/powerpc/mod-tlsopt-powerpc.c: Extract from
tst-tlsopt-powerpc.c with function name change and no test harness.
* sysdeps/powerpc/tst-tlsopt-powerpc.c: Remove body of test.
Call tls_get_addr_opt_test.
* sysdeps/powerpc/Makefile (LDFLAGS-tst-tlsopt-powerpc): Don't define.
(modules-names): Add mod-tlsopt-powerpc.
(mod-tlsopt-powerpc.so-no-z-defs): Define.
(tst-tlsopt-powerpc): Depend on .so.
* sysdeps/powerpc/powerpc64/tls-macros.h (__TLS_GET_ADDR): Don't
define. Expand use in TLS_GD and TLS_LD.
csu/libc-start.c now insists on calling __libc_init_secure, while the Hurd
port already implements it "very early" in dl-sysdep.c and init-first.c
* sysdeps/mach/hurd/enbl-secure.c (__libc_init_secure): Define
function.
There is no need to define multiarch __memmove_chk in libc.a since they
aren't used at all.
[BZ #21791]
* sysdeps/i386/i686/multiarch/memcpy-sse2-unaligned.S
(MEMCPY_CHK): Define only if SHARED is defined.
* sysdeps/i386/i686/multiarch/memcpy-ssse3-rep.S (MEMCPY_CHK):
Likewise.
* sysdeps/i386/i686/multiarch/memcpy-ssse3.S (MEMCPY_CHK):
Likewise.
The relative branch directly to __libc_vfork results in an relocation
that cannot be resolved. Specifically a R_MICROBLAZE_64_PCREL relocation
is created for this branch, however for MicroBlaze R_MICROBLAZE_64_PCREL
type relocations symbols are not resolved. Additionally due to the
branch being located in the .text section the instruction cannot be
rewritten as the section is not writable, and causes a segfault at
runtime when loading libpthread.
To resolve this issue, ensure the branch is done using PLT. This removes
the need to modify the instruction and trades the R_MICROBLAZE_64_PCREL
for a more common R_MICROBLAZE_JUMP via the PLT.
[BZ #21779]
* sysdeps/unix/sysv/linux/microblaze/pt-vfork.S: Branch using PLT.
The function maybe_enable_malloc_check, which is called by
__tunables_init, calls __access_noerrno. It isn't problem when
symbol is is in ld.so, which has a special version of __access_noerrno
without stack protector. But when glibc is built with stack protector,
maybe_enable_malloc_check in libc.a can't call the regular version of
__access_noerrno with stack protector.
This patch changes how Linux defines the __access_noerrno to be an
inline call instead and thus preventing defining different build
rules for ld/static and shared.
H.J. Lu <hongjiu.lu@intel.com>
Adhemerval Zanella <adhemerval.zanella@linaro.org>
[BZ #21744]
* elf/dl-tunables.c: Include not-errno.h header.
* include/unistd.h (__access_noerrno): Remove definition.
* sysdeps/unix/sysv/linux/access.c (__access_noerrno): Likewise.
* sysdeps/generic/not-errno.h: New file.
* sysdeps/unix/sysv/linux/not-errno.h: Likewise.
__libc_argv[0] points to address on stack and __libc_secure_getenv
accesses environment variables which are on stack. We should avoid
accessing stack when stack is corrupted.
This patch also renames function argument in __fortify_fail_abort
from do_backtrace to need_backtrace to avoid confusion with do_backtrace
from enum __libc_message_action.
[BZ #21752]
* debug/fortify_fail.c (__fortify_fail_abort): Don't pass down
__libc_argv[0] if we aren't doing backtrace. Rename do_backtrace
to need_backtrace.
* sysdeps/posix/libc_fatal.c (__libc_message): Don't call
__libc_secure_getenv if we aren't doing backtrace.
sys/ptrace.h on S390 used to be includible both before and after
asm/ptrace.h, until commit b08a6a0dea
among other changes introduced PTRACE_SINGLEBLOCK enum constant which
is also defined in asm/ptrace.h as a macro, making sys/ptrace.h fail
to compile when included after asm/ptrace.h.
* sysdeps/unix/sysv/linux/s390/sys/ptrace.h [_LINUX_PTRACE_H ||
_S390_PTRACE_H]: Undefine all PTRACE_* macro constants defined
later as enum constants, except PTRACE_PEEKUSER, PTRACE_POKEUSER,
and PTRACE_SEIZE_DEVEL that are not defined by Linux headers.
This patch fixes the argument passing for exit syscall after
the clone function returns on hppa. This fixes misc/tst-clone2
on alpha-linux-gnu.
Checked misc/tst-clone2 on alpha-linux-gnu.
[BZ #21512]
* sysdeps/unix/sysv/linux/alpha/clone.S (__clone): Fix argument
passing to syscall exit.
Since there are no multiarch versions of memmove_chk and memset_chk,
test multiarch versions of memmove_chk and memset_chk only in libc.so.
[BZ #21741]
* sysdeps/i386/i686/multiarch/ifunc-impl-list.c
(__libc_ifunc_impl_list): Test memmove_chk and memset_chk only
in libc.so.
The patch proposed by Peter Bergner [1] to libgcc in order to fix
[BZ #21707] adds a dependency on a symbol provided by the loader,
forcing the loader to be linked to tests after libgcc was linked.
It also requires to read the thread pointer during IRELA relocations.
Tested on powerpc, powerpc64, powerpc64le, s390x and x86_64.
[1] https://sourceware.org/ml/libc-alpha/2017-06/msg01383.html
[BZ #21707]
* csu/libc-start.c (LIBC_START_MAIN): Perform IREL{,A}
relocations before or after initializing the TCB on statically
linked executables. That's a per-architecture definition.
* elf/rtld.c (dl_main): Add a comment about thread-local
variables initialization.
* sysdeps/generic/libc-start.h: New file. Define
ARCH_APPLY_IREL and ARCH_SETUP_IREL.
* sysdeps/powerpc/Makefile:
[$(subdir) = elf && $(multi-arch) != no] (tests-static-internal): Add tst-tlsifunc-static.
[$(subdir) = elf && $(multi-arch) != no && $(build-shared) == yes]
(tests-internal): Add tst-tlsifunc.
* sysdeps/powerpc/tst-tlsifunc.c: New file.
* sysdeps/powerpc/tst-tlsifunc-static.c: Likewise.
* sysdeps/powerpc/powerpc64le/Makefile (f128-loader-link): New
variable.
[$(subdir) = math] (test-float128% test-ifloat128%): Force
linking to the loader after linking to libgcc.
[$(subdir) = wcsmbs || $(subdir) = stdlib] (bug-strtod bug-strtod2)
(bug-strtod2 tst-strtod-round tst-wcstod-round tst-strtod6 tst-strrom)
(tst-strfrom-locale strfrom-skeleton): Likewise.
* sysdeps/unix/sysv/linux/powerpc/libc-start.h: New file. Define
ARCH_APPLY_IREL and ARCH_SETUP_IREL.
This patch fixes the argument passing for exit syscall after
the clone function returns on hppa. This fixes misc/tst-clone2
on hppa-linux-gnu.
Checked misc/tst-clone2 on hppa-linux-gnu.
[BZ #21512]
* sysdeps/unix/sysv/linux/hppa/clone.S (__clone): Fix argument
passing to syscall exit.
This patch adds the HWCAP_JSCVT, HWCAP_FCMA and HWCAP_LRCPC macros
from Linux 4.12 to the AArch64 bits/hwcap.h.
* sysdeps/unix/sysv/linux/aarch64/bits/hwcap.h (HWCAP_FCMA): New macro.
(HWCAP_JSCVT, HWCAP_LRCPC): Likewise.
