Various glibc testcases use tmpnam in ways subject to race conditions
(generate a temporary file name, then later open that file without
O_EXCL).
This patch fixes those tests to use mkstemp - generally a minimal
local fix to use mkstemp instead of tmpnam, rather than a larger fix
to use other testsuite infrastructure for temporary files. The
unchanged use of tmpnam in posix/wordexp-test.c would fail safe in the
event of a race (it's generating a name for use with mkdir rather than
for a file to be opened for writing).
Tested for x86_64.
* grp/tst_fgetgrent.c: Include <unistd.h>.
(main): Use mkstemp instead of tmpnam.
* io/test-utime.c (main): Likewise.
* posix/annexc.c (macrofile): Change to modifiable array.
(get_null_defines): Use mkstemp instead of tmpnam. Do not remove
macrofile here.
* posix/bug-getopt1.c: Include <stdlib.h>.
(do_test): Use mkstemp instead of tmpnam.
* posix/bug-getopt2.c: Include <stdlib.h>.
(do_test): Use mkstemp instead of tmpnam.
* posix/bug-getopt3.c: Include <stdlib.h>.
(do_test): Use mkstemp instead of tmpnam.
* posix/bug-getopt4.c: Include <stdlib.h>.
(do_test): Use mkstemp instead of tmpnam.
* posix/bug-getopt5.c: Include <stdlib.h>.
(do_test): Use mkstemp instead of tmpnam.
* stdio-common/bug7.c: Include <stdlib.h> and <unistd.h>.
(main): Use mkstemp instead of tmpnam.
* stdio-common/tst-fdopen.c: Include <stdlib.h>.
(main): Use mkstemp instead of tmpnam.
* stdio-common/tst-ungetc.c: Include <stdlib.h>.
(main): use mkstemp instead of tmpnam.
* stdlib/isomac.c (macrofile): Change to modifiable array.
(get_null_defines): Use mkstemp instead of tmpnam. Do not remove
macrofile here.
i386 add_n.S and sub_n.S use a trick to implment jump tables with LEA.
We can't use conditional branches nor normal jump tables since jump
table entries use EFLAGS set by jump table index. This patch adds
_CET_ENDBR to indirect jump targets and adjust destination for
_CET_ENDBR.
Reviewed-by: Carlos O'Donell <carlos@redhat.com>
* sysdeps/i386/add_n.S: Include <sysdep.h>, instead of
"sysdep.h".
(__mpn_add_n): Save and restore %ebx if IBT is enabed. Add
_CET_ENDBR to indirect jump targets and adjust jump destination
for _CET_ENDBR.
* sysdeps/i386/i686/add_n.S: Include <sysdep.h>, instead of
"sysdep.h".
(__mpn_add_n): Save and restore %ebx if IBT is enabed. Add
_CET_ENDBR to indirect jump targets and adjust jump destination
for _CET_ENDBR.
* sysdeps/i386/sub_n.S: Include <sysdep.h>, instead of
"sysdep.h".
(__mpn_sub_n): Save and restore %ebx if IBT is enabed. Add
_CET_ENDBR to indirect jump targets and adjust jump destination
for _CET_ENDBR.
Add _CET_ENDBR to STRCMP_SSE42, which is called indirectly, to support
IBT.
Reviewed-by: Carlos O'Donell <carlos@redhat.com>
* sysdeps/x86_64/multiarch/strcmp-sse42.S (STRCMP_SSE42): Add
_CET_ENDBR.
Add _CET_ENDBR to functions in crti.S, which are called indirectly, to
support IBT.
Tested on i686 and x86-64.
Reviewed-by: Carlos O'Donell <carlos@redhat.com>
* sysdeps/i386/crti.S (_init): Add _CET_ENDBR.
(_fini): Likewise.
* sysdeps/x86_64/crti.S (_init): Likewise.
(_fini): Likewise.
Always include <dl-cet.h> and cet-tunables.h> when CET is enabled.
Otherwise, configure glibc with --enable-cet --disable-tunables will
fail to build.
* sysdeps/x86/cpu-features.c: Always include <dl-cet.h> and
cet-tunables.h> when CET is enabled.
Intel Control-flow Enforcement Technology (CET) instructions:
https://software.intel.com/sites/default/files/managed/4d/2a/control-flow-en
forcement-technology-preview.pdf
includes Indirect Branch Tracking (IBT) and Shadow Stack (SHSTK).
GNU_PROPERTY_X86_FEATURE_1_IBT is added to GNU program property to
indicate that all executable sections are compatible with IBT when
ENDBR instruction starts each valid target where an indirect branch
instruction can land. Linker sets GNU_PROPERTY_X86_FEATURE_1_IBT on
output only if it is set on all relocatable inputs.
On an IBT capable processor, the following steps should be taken:
1. When loading an executable without an interpreter, enable IBT and
lock IBT if GNU_PROPERTY_X86_FEATURE_1_IBT is set on the executable.
2. When loading an executable with an interpreter, enable IBT if
GNU_PROPERTY_X86_FEATURE_1_IBT is set on the interpreter.
a. If GNU_PROPERTY_X86_FEATURE_1_IBT isn't set on the executable,
disable IBT.
b. Lock IBT.
3. If IBT is enabled, when loading a shared object without
GNU_PROPERTY_X86_FEATURE_1_IBT:
a. If legacy interwork is allowed, then mark all pages in executable
PT_LOAD segments in legacy code page bitmap. Failure of legacy code
page bitmap allocation causes an error.
b. If legacy interwork isn't allowed, it causes an error.
GNU_PROPERTY_X86_FEATURE_1_SHSTK is added to GNU program property to
indicate that all executable sections are compatible with SHSTK where
return address popped from shadow stack always matches return address
popped from normal stack. Linker sets GNU_PROPERTY_X86_FEATURE_1_SHSTK
on output only if it is set on all relocatable inputs.
On a SHSTK capable processor, the following steps should be taken:
1. When loading an executable without an interpreter, enable SHSTK if
GNU_PROPERTY_X86_FEATURE_1_SHSTK is set on the executable.
2. When loading an executable with an interpreter, enable SHSTK if
GNU_PROPERTY_X86_FEATURE_1_SHSTK is set on interpreter.
a. If GNU_PROPERTY_X86_FEATURE_1_SHSTK isn't set on the executable
or any shared objects loaded via the DT_NEEDED tag, disable SHSTK.
b. Otherwise lock SHSTK.
3. After SHSTK is enabled, it is an error to load a shared object
without GNU_PROPERTY_X86_FEATURE_1_SHSTK.
To enable CET support in glibc, --enable-cet is required to configure
glibc. When CET is enabled, both compiler and assembler must support
CET. Otherwise, it is a configure-time error.
To support CET run-time control,
1. _dl_x86_feature_1 is added to the writable ld.so namespace to indicate
if IBT or SHSTK are enabled at run-time. It should be initialized by
init_cpu_features.
2. For dynamic executables:
a. A l_cet field is added to struct link_map to indicate if IBT or
SHSTK is enabled in an ELF module. _dl_process_pt_note or
_rtld_process_pt_note is called to process PT_NOTE segment for
GNU program property and set l_cet.
b. _dl_open_check is added to check IBT and SHSTK compatibilty when
dlopening a shared object.
3. Replace i386 _dl_runtime_resolve and _dl_runtime_profile with
_dl_runtime_resolve_shstk and _dl_runtime_profile_shstk, respectively if
SHSTK is enabled.
CET run-time control can be changed via GLIBC_TUNABLES with
$ export GLIBC_TUNABLES=glibc.tune.x86_shstk=[permissive|on|off]
$ export GLIBC_TUNABLES=glibc.tune.x86_ibt=[permissive|on|off]
1. permissive: SHSTK is disabled when dlopening a legacy ELF module.
2. on: IBT or SHSTK are always enabled, regardless if there are IBT or
SHSTK bits in GNU program property.
3. off: IBT or SHSTK are always disabled, regardless if there are IBT or
SHSTK bits in GNU program property.
<cet.h> from CET-enabled GCC is automatically included by assembly codes
to add GNU_PROPERTY_X86_FEATURE_1_IBT and GNU_PROPERTY_X86_FEATURE_1_SHSTK
to GNU program property. _CET_ENDBR is added at the entrance of all
assembly functions whose address may be taken. _CET_NOTRACK is used to
insert NOTRACK prefix with indirect jump table to support IBT. It is
defined as notrack when _CET_NOTRACK is defined in <cet.h>.
[BZ #21598]
* configure.ac: Add --enable-cet.
* configure: Regenerated.
* elf/Makefille (all-built-dso): Add a comment.
* elf/dl-load.c (filebuf): Moved before "dynamic-link.h".
Include <dl-prop.h>.
(_dl_map_object_from_fd): Call _dl_process_pt_note on PT_NOTE
segment.
* elf/dl-open.c: Include <dl-prop.h>.
(dl_open_worker): Call _dl_open_check.
* elf/rtld.c: Include <dl-prop.h>.
(dl_main): Call _rtld_process_pt_note on PT_NOTE segment. Call
_rtld_main_check.
* sysdeps/generic/dl-prop.h: New file.
* sysdeps/i386/dl-cet.c: Likewise.
* sysdeps/unix/sysv/linux/x86/cpu-features.c: Likewise.
* sysdeps/unix/sysv/linux/x86/dl-cet.h: Likewise.
* sysdeps/x86/cet-tunables.h: Likewise.
* sysdeps/x86/check-cet.awk: Likewise.
* sysdeps/x86/configure: Likewise.
* sysdeps/x86/configure.ac: Likewise.
* sysdeps/x86/dl-cet.c: Likewise.
* sysdeps/x86/dl-procruntime.c: Likewise.
* sysdeps/x86/dl-prop.h: Likewise.
* sysdeps/x86/libc-start.h: Likewise.
* sysdeps/x86/link_map.h: Likewise.
* sysdeps/i386/dl-trampoline.S (_dl_runtime_resolve): Add
_CET_ENDBR.
(_dl_runtime_profile): Likewise.
(_dl_runtime_resolve_shstk): New.
(_dl_runtime_profile_shstk): Likewise.
* sysdeps/linux/x86/Makefile (sysdep-dl-routines): Add dl-cet
if CET is enabled.
(CFLAGS-.o): Add -fcf-protection if CET is enabled.
(CFLAGS-.os): Likewise.
(CFLAGS-.op): Likewise.
(CFLAGS-.oS): Likewise.
(asm-CPPFLAGS): Add -fcf-protection -include cet.h if CET
is enabled.
(tests-special): Add $(objpfx)check-cet.out.
(cet-built-dso): New.
(+$(cet-built-dso:=.note)): Likewise.
(common-generated): Add $(cet-built-dso:$(common-objpfx)%=%.note).
($(objpfx)check-cet.out): New.
(generated): Add check-cet.out.
* sysdeps/x86/cpu-features.c: Include <dl-cet.h> and
<cet-tunables.h>.
(TUNABLE_CALLBACK (set_x86_ibt)): New prototype.
(TUNABLE_CALLBACK (set_x86_shstk)): Likewise.
(init_cpu_features): Call get_cet_status to check CET status
and update dl_x86_feature_1 with CET status. Call
TUNABLE_CALLBACK (set_x86_ibt) and TUNABLE_CALLBACK
(set_x86_shstk). Disable and lock CET in libc.a.
* sysdeps/x86/cpu-tunables.c: Include <cet-tunables.h>.
(TUNABLE_CALLBACK (set_x86_ibt)): New function.
(TUNABLE_CALLBACK (set_x86_shstk)): Likewise.
* sysdeps/x86/sysdep.h (_CET_NOTRACK): New.
(_CET_ENDBR): Define if not defined.
(ENTRY): Add _CET_ENDBR.
* sysdeps/x86/dl-tunables.list (glibc.tune): Add x86_ibt and
x86_shstk.
* sysdeps/x86_64/dl-trampoline.h (_dl_runtime_resolve): Add
_CET_ENDBR.
(_dl_runtime_profile): Likewise.
This patch changes longjmp to always restore the TOC pointer (r2 register)
to the caller frame on powerpc64 and powerpc64le. This is related to bug
21895 that reports a situation where you have a static longjmp to a
shared object file.
[BZ #21895]
* sysdeps/powerpc/powerpc64/__longjmp-common.S: Remove condition code for
restoring r2 in longjmp.
* sysdeps/powerpc/powerpc64/Makefile: Added tst-setjmp-bug21895-static to
test list.
Added rules to build test tst-setjmp-bug21895-static.
Added module setjmp-bug21895 and rules to build a shared object from it.
* sysdeps/powerpc/powerpc64/setjmp-bug21895.c: New test file.
* sysdeps/powerpc/powerpc64/tst-setjmp-bug21895-static.c: New test file.
Reviewed-by: Tulio Magno Quites Machado Filho <tuliom@linux.ibm.com>
Improve strstr performance. Strstr tends to be slow because it uses
many calls to memchr and a slow byte loop to scan for the next match.
Performance is significantly improved by using strnlen on larger blocks
and using strchr to search for the next matching character. strcasestr
can also use strnlen to scan ahead, and memmem can use memchr to check
for the next match.
On the GLIBC bench tests the performance gains on Cortex-A72 are:
strstr: +25%
strcasestr: +4.3%
memmem: +18%
On a 256KB dataset strstr performance improves by 67%, strcasestr by 47%.
Reviewd-by: Adhemerval Zanella <adhemerval.zanella@linaro.org>
Since SHADOW_STACK_POINTER_OFFSET is defined in jmp_buf-ssp.h, we must
undef SHADOW_STACK_POINTER_OFFSET after including <jmp_buf-ssp.h>.
* sysdeps/unix/sysv/linux/x86_64/____longjmp_chk.S: Undef
SHADOW_STACK_POINTER_OFFSET after including <jmp_buf-ssp.h>.
Save and restore shadow stack pointer in setjmp and longjmp to support
shadow stack in Intel CET. Use feature_1 in tcbhead_t to check if
shadow stack is enabled before saving and restoring shadow stack pointer.
Reviewed-by: Carlos O'Donell <carlos@redhat.com>
* sysdeps/i386/__longjmp.S: Include <jmp_buf-ssp.h>.
(__longjmp): Restore shadow stack pointer if shadow stack is
enabled, SHADOW_STACK_POINTER_OFFSET is defined and __longjmp
isn't defined for __longjmp_cancel.
* sysdeps/i386/bsd-_setjmp.S: Include <jmp_buf-ssp.h>.
(_setjmp): Save shadow stack pointer if shadow stack is enabled
and SHADOW_STACK_POINTER_OFFSET is defined.
* sysdeps/i386/bsd-setjmp.S: Include <jmp_buf-ssp.h>.
(setjmp): Save shadow stack pointer if shadow stack is enabled
and SHADOW_STACK_POINTER_OFFSET is defined.
* sysdeps/i386/setjmp.S: Include <jmp_buf-ssp.h>.
(__sigsetjmp): Save shadow stack pointer if shadow stack is
enabled and SHADOW_STACK_POINTER_OFFSET is defined.
* sysdeps/unix/sysv/linux/i386/____longjmp_chk.S: Include
<jmp_buf-ssp.h>.
(____longjmp_chk): Restore shadow stack pointer if shadow stack
is enabled and SHADOW_STACK_POINTER_OFFSET is defined.
* sysdeps/unix/sysv/linux/x86/Makefile (gen-as-const-headers):
Remove jmp_buf-ssp.sym.
* sysdeps/unix/sysv/linux/x86_64/____longjmp_chk.S: Include
<jmp_buf-ssp.h>.
(____longjmp_chk): Restore shadow stack pointer if shadow stack
is enabled and SHADOW_STACK_POINTER_OFFSET is defined.
* sysdeps/x86/Makefile (gen-as-const-headers): Add
jmp_buf-ssp.sym.
* sysdeps/x86/jmp_buf-ssp.sym: New dummy file.
* sysdeps/x86_64/__longjmp.S: Include <jmp_buf-ssp.h>.
(__longjmp): Restore shadow stack pointer if shadow stack is
enabled, SHADOW_STACK_POINTER_OFFSET is defined and __longjmp
isn't defined for __longjmp_cancel.
* sysdeps/x86_64/setjmp.S: Include <jmp_buf-ssp.h>.
(__sigsetjmp): Save shadow stack pointer if shadow stack is
enabled and SHADOW_STACK_POINTER_OFFSET is defined.
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.
Fixed syntax error in the collation rules of Lower Sorbian language.
Collation test added in order to test the bugs like this early.
Reported-by: Tulio Magno Quites Machado Filho <tuliom@linux.ibm.com>
[BZ #23208]
* localedata/Makefile (test-input): Add dsb_DE.UTF-8.
(LOCALES): Likewise.
* localedata/dsb_DE.UTF-8.in: New file.
* localedata/locales/dsb_DE (LC_COLLATE): Fix syntax error.
In some places there was still the old Unicode version 10.0.0 in the files.
* localedata/charmaps/UTF-8: Use correct Unicode version 11.0.0 in comment.
* localedata/locales/i18n_ctype: Use correct Unicode version in comments
and headers.
* localedata/unicode-gen/utf8_gen.py: Add option to specify Unicode version
* localedata/unicode-gen/Makefile: Use option to specify Unicode version
for utf8_gen.py
As pointed out in a libc-alpha thread [1], the misc/tst-ofdlocks-compat
may fail in some specific Linux releases. This patch adds a comment
along with a link to discussion in the test source code.
No changes are expected.
* sysdeps/unix/sysv/linux/tst-ofdlocks-compat.c: Add a comment about
a kernel issue which lead to test failure in some cases.
[1] https://sourceware.org/ml/libc-alpha/2018-07/msg00243.html
Each weight is prefixed by its length, and the length does not include
itself in the count. This can be seen clearly from the find_idx
function in string/strxfrm_l.c, for example. The old code behaved as if
the length itself counted, thus comparing an additional byte after the
weight, leading to spurious comparison failures and incorrect further
partitioning of character equivalence classes.
This is a variant of fgets which fails with ERANGE if the
buffer is too small, and the buffer length is given as an
argument of type size_t.
This function will be useful for implementing NSS file reading
operations. Compared to a direct implementation using the public API,
it avoids an lseek system call in case the line terminator can be
found in the internal read buffer.
This enables searching shared libraries in atomics/ when the hardware
supports LSE atomics of armv8.1 so one can provide optimized variants
of libraries in a portable way.
LSE atomics does not affect library abi, the new instructions can
interoperate with old ones.
I considered the earlier comments on the patch
https://sourceware.org/ml/libc-alpha/2018-04/msg00400.htmlhttps://sourceware.org/ml/libc-alpha/2018-04/msg00625.html
It turns out that the way glibc dynamic linker decides on the search
path is not very flexible: it wants to use hwcap bits and associated
strings. So some targets reuse hwcap bits for glibc internal purposes
to affect the search logic. But hwcap is an interface with the kernel,
glibc should not allocate bits in it for its internal logic as that
limits future hwcap extensions and confusing to users who expect to see
hwcap bits in ifunc resolvers. Instead of rewriting the dynamic linker
path logic (which affects all targets) this patch just uses the existing
mechanism, however this means that the path name has to be the hwcap
name "atomics" and cannot be changed to something more meaningful to
users.
It is hard to tell how much performance benefit this can give, in
principle armv8.1 atomics can be better optimized in the hardware, so it
can make a difference for synchronization heavy code. On some systems
such multilib setup may be the only viable way to get optimized
libraries used.
* sysdeps/unix/sysv/linux/aarch64/dl-procinfo.h (HWCAP_IMPORTANT): Add
HWCAP_ATOMICS.
This partially reverts
commit f82e9672ad
Author: Siddhesh Poyarekar <siddhesh@sourceware.org>
aarch64: Allow overriding HWCAP_CPUID feature check using HWCAP_MASK
The idea was to make it possible to disable cpuid based ifunc resolution
in glibc by changing the hwcap mask which the user could already control.
However the hwcap mask has an orthogonal role: it specifies additional
library search paths for the dynamic linker. So "cpuid" got added to
the search paths when it was set in the default mask (HWCAP_IMPORTANT),
which is not useful behaviour, the hwcap masking should not be reused
in the cpu features code.
Meanwhile there is a tunable to set the cpu explicitly so it is possible
to disable the cpuid based dispatch without using a hwcap mask:
GLIBC_TUNABLES=glibc.tune.cpu=generic
* sysdeps/unix/sysv/linux/aarch64/cpu-features.c (init_cpu_features):
Use dl_hwcap without masking.
* sysdeps/unix/sysv/linux/aarch64/dl-procinfo.h (HWCAP_IMPORTANT):
Remove HWCAP_CPUID.
This suppresses Perl warnings like these:
Unescaped left brace in regex is deprecated here (and will be fatal in
Perl 5.32), passed through in regex; marked by <-- HERE in m/^element
*({ <-- HERE ([^}]*)}|([^{ ]*)) *({([^}]*)}|([^{ ]*)) *([A-Za-z0-9_]*)
*(.*)/ at conformtest.pl line 370.
Reviewed-by: Carlos O'Donell <carlos@redhat.com>
From Zen onwards this will be enabled. It was disabled for the
Excavator case and will remain disabled.
Reviewd-by: Carlos O'Donell <carlos@redhat.com>
This does not change generated code (with -fstack-protector-strong), but
is important for formal compiler flags compliance.
Reviewed-by: Carlos O'Donell <carlos@redhat.com>
Define a new ABSOLUTE ABI for static linker's use with EI_ABIVERSION
where correct absolute (SHN_ABS) symbol run-time load semantics is
required. This way it can be ensured at static link time that a program
or DSO will not suffer from previous semantics where absolute symbols
were relocated by the base address, or symbols whose `st_value' is zero
silently ignored leading to a confusing "undefined symbol" error message
at load time, and instead "ELF file ABI version invalid" is printed with
old dynamic loaders, making it clear that there is an ABI version
incompatibility.
[BZ #19818]
[BZ #23307]
* libc-abis (ABSOLUTE): New ABI.
* sysdeps/unix/sysv/linux/mips/libc-abis (ABSOLUTE): New ABI.
* NEWS: Mention the new ABI.
Reviewed-by: Carlos O'Donell <carlos@redhat.com>
The implementation falls back to renameat if renameat2 is not available
in the kernel (or in the kernel headers) and the flags argument is zero.
Without kernel support, a non-zero argument returns EINVAL, not ENOSYS.
This mirrors what the kernel does for invalid renameat2 flags.
On some platforms the inclusion of regex-internal.h in bug-regex33
testcase show a MAX redefinition if test-skeleton.c is include later.
This patch fixes by removing regex-internal.h inclusion and using
SBC_MAX value directly.
Checked on aarch64-linux-gnu.
* posix/bug-regex33.c: Fix build after regex sync.
There is a glibc optimization which allows for locale categories
to be removed during static compilation. There have been various
bugs for this support over the years, with bug 16915 being the
most recent. The solution there was to emit a reference to all the
categories to avoid any being removed. This fix, although it's in
the generic __nl_langinfo_l function, doesn't appear to be enough
to fix the case for a statically linked program that uses newlocale
and nl_langinfo_l. This commit doesn't fix the problem, but it does
add a XFAIL'd test case such that a fix can be applied against this
and the XFAIL removed. It's not entirely clear that the problem is
the same as that which was seen in bug 16915.
