The libc version is identical and built with same flags. The libc
version is set as the default version.
The libpthread compat symbol requires to mask it when building the
loader object otherwise ld might complain about a missing
versioned symbol (as for alpha).
Checked on x86_64-linux-gnu.
The libc version is identical and built with same flags. Both aarch64
and nios2 also requires to export __send and tt was done previously with
the HAVE_INTERNAL_SEND_SYMBOL (which forced the symbol creation).
All __send callers are internal to libc and the original issue that
required the symbol export was due a missing libc_hidden_def. So
a compat symbol is added for __send and the libc_hidden_def is
defined regardless.
Checked on x86_64-linux-gnu and i686-linux-gnu.
The generic implementation basically handle the system agnostic logic
(filtering out the invalid signals) while the __libc_sigaction is
the function with implements the system and architecture bits.
Checked on x86_64-linux-gnu and i686-linux-gnu.
It turns out the startup code in csu/elf-init.c has a perfect pair of
ROP gadgets (see Marco-Gisbert and Ripoll-Ripoll, "return-to-csu: A
New Method to Bypass 64-bit Linux ASLR"). These functions are not
needed in dynamically-linked binaries because DT_INIT/DT_INIT_ARRAY
are already processed by the dynamic linker. However, the dynamic
linker skipped the main program for some reason. For maximum
backwards compatibility, this is not changed, and instead, the main
map is consulted from __libc_start_main if the init function argument
is a NULL pointer.
For statically linked binaries, the old approach based on linker
symbols is still used because there is nothing else available.
A new symbol version __libc_start_main@@GLIBC_2.34 is introduced because
new binaries running on an old libc would not run their ELF
constructors, leading to difficult-to-debug issues.
This was likely a mistake in the original aarch64 port copied over
from arm: on aarch64 tpidr_el0 register is always available.
The __read_tp symbol is visible with static linking, but it's not
part of the public ABI so it should be safe to remove.
Linux 5.11 has one new syscall, epoll_pwait2. Update
syscall-names.list and regenerate the arch-syscall.h headers with
build-many-glibcs.py update-syscalls.
Tested with build-many-glibcs.py.
If the linux asm/ptrace.h is included before sys/ptrace.h that
breaks the newly added declarations there, so undef the names
that may be defined as macros in the linux header.
The XSTAT_IS_XSTAT64 and STAT_IS_KERNEL_STAT flags are now set to 1 and
STATFS_IS_STATFS64 is set to __STATFS_MATCHES_STATFS64. This makes the
default ABI for newer ports to provide only LFS calls.
A copy of non-LFS support is provided to 32-bit ABIS with non-LFS
support (arm, csky, i386, m68k, nios2, s390, and sh). Is also allows
to remove the 64-bit ports, which already uses the default values.
This patch does not change the code generation.
Reviewed-by: Carlos O'Donell <carlos@redhat.com>
aarch64, arc, ia64, mips64, powerpc64, riscv32, riscv64, s390x, sparc64,
and x86_64 defines STATFS_IS_STATFS64 to 0, but all of them alias
statfs to statfs64 and the struct statfs has the same and layout of
struct statfs64.
The correct definition will be used on the [f]statfs[64] consolidation.
This patch does not change code generation since the symbols are
implemented using the auto-generation syscall for all the aforementioned
ABIs.
Reviewed-by: Carlos O'Donell <carlos@redhat.com>
The TUNABLE_SET interface took a primitive C type argument, which
resulted in inconsistent type conversions internally due to incorrect
dereferencing of types, especialy on 32-bit architectures. This
change simplifies the TUNABLE setting logic along with the interfaces.
Now all numeric tunable values are stored as signed numbers in
tunable_num_t, which is intmax_t. All calls to set tunables cast the
input value to its primitive type and then to tunable_num_t for
storage. This relies on gcc-specific (although I suspect other
compilers woul also do the same) unsigned to signed integer conversion
semantics, i.e. the bit pattern is conserved. The reverse conversion
is guaranteed by the standard.
Linux 5.10 adds PTRACE_PEEKMTETAGS and PTRACE_POKEMTETAGS for AArch64.
Adding those shows up that glibc is also missing PTRACE_SYSEMU and
PTRACE_SYSEMU_SINGLESTEP, for AArch64 (where they were added to Linux
in 5.3) and for PowerPC (where they were added in Linux 4.20); it
already has those two defines for x86. Add all those defines to
glibc's headers.
Tested with build-many-glibcs.py for aarch64-linux-gnu and
powerpc-linux-gnu.
Extern symbol access in position independent code usually involves GOT
indirection which needs RELATIVE reloc in a static linked PIE. (On
some targets this is avoided e.g. because the linker can relax a GOT
access to a pc-relative access, but this is not generally true.) Code
that runs before static PIE self relocation must avoid relying on
dynamic relocations which can be ensured by using hidden visibility.
However we cannot just make all symbols hidden:
On i386, all calls to IFUNC functions must go through PLT and calls to
hidden functions CANNOT go through PLT in PIE since EBX used in PIE PLT
may not be set up for local calls to hidden IFUNC functions.
This patch aims to make symbol references hidden in code that is used
before and by _dl_relocate_static_pie when building a static PIE libc.
Note: for an object that is used in the startup code, its references
and definition may not have consistent visibility: it is only forced
hidden in the startup code.
This is needed for fixing bug 27072.
Co-authored-by: H.J. Lu <hjl.tools@gmail.com>
Reviewed-by: Adhemerval Zanella <adhemerval.zanella@linaro.org>
I used these shell commands:
../glibc/scripts/update-copyrights $PWD/../gnulib/build-aux/update-copyright
(cd ../glibc && git commit -am"[this commit message]")
and then ignored the output, which consisted lines saying "FOO: warning:
copyright statement not found" for each of 6694 files FOO.
I then removed trailing white space from benchtests/bench-pthread-locks.c
and iconvdata/tst-iconv-big5-hkscs-to-2ucs4.c, to work around this
diagnostic from Savannah:
remote: *** pre-commit check failed ...
remote: *** error: lines with trailing whitespace found
remote: error: hook declined to update refs/heads/master
DELOUSE was added to asm code to make them compatible with non-LP64
ABIs, but it is an unfortunate name and the code was not compatible
with ABIs where pointer and size_t are different. Glibc currently
only supports the LP64 ABI so these macros are not really needed or
tested, but for now the name is changed to be more meaningful instead
of removing them completely.
Some DELOUSE macros were dropped: clone, strlen and strnlen used it
unnecessarily.
The out of tree ILP32 patches are currently not maintained and will
likely need a rework to rebase them on top of the time64 changes.
Add various defines and stubs for enabling MTE on AArch64 sysv-like
systems such as Linux. The HWCAP feature bit is copied over in the
same way as other feature bits. Similarly we add a new wrapper header
for mman.h to define the PROT_MTE flag that can be used with mmap and
related functions.
We add a new field to struct cpu_features that can be used, for
example, to check whether or not certain ifunc'd routines should be
bound to MTE-safe versions.
Finally, if we detect that MTE should be enabled (ie via the glibc
tunable); we enable MTE during startup as required.
Support in the Linux kernel was added in version 5.10.
Reviewed-by: Szabolcs Nagy <szabolcs.nagy@arm.com>
Linux 5.10 has one new syscall, process_madvise. Update
syscall-names.list and regenerate the arch-syscall.h headers with
build-many-glibcs.py update-syscalls.
Tested with build-many-glibcs.py.
It removes all the arch-specific assembly implementation. The
outliers are alpha, where its kernel ABI explict return -ENOMEM
in case of failure; and i686, where it can't use
"call *%gs:SYSINFO_OFFSET" during statup in static PIE.
Also some ABIs exports an additional ___brk_addr symbol and to
handle it an internal HAVE_INTERNAL_BRK_ADDR_SYMBOL is added.
Checked on x86_64-linux-gnu, i686-linux-gnu, adn with builsd for
the affected ABIs.
Reviewed-by: Tulio Magno Quites Machado Filho <tuliom@linux.ibm.com>
Linux 5.9 has one new syscall, close_range. Update syscall-names.list
and regenerate the arch-syscall.h headers with build-many-glibcs.py
update-syscalls.
Tested with build-many-glibcs.py.
Add CPU detection of Neoverse N2 and Neoverse V1, and select __memcpy_simd as
the memcpy/memmove ifunc.
Reviewed-by: Adhemerval Zanella <adhemerval.zanella@linaro.org>
This patch removes the mknod and mknodat static wrapper and add the
symbols on the libc with the expected names.
Both the prototypes of the internal symbol linked by the static
wrappers and the inline redirectors are also removed from the installed
sys/stat.h header file. The wrapper implementation license LGPL
exception is also removed since it is no longer statically linked to
binaries.
Internally the _STAT_VER* definitions are moved to the arch-specific
xstatver.h file.
Checked with a build for all affected ABIs. I also checked on x86_64,
i686, powerpc, powerpc64le, sparcv9, sparc64, s390, and s390x.
Reviewed-by: Lukasz Majewski <lukma@denx.de>
This patch removes the stat, stat64, lstat, lstat64, fstat, fstat64,
fstatat, and fstatat64 static wrapper and add the symbol on the libc
with the expected names.
Both the prototypes of the internal symbol linked by the static
wrappers and the inline redirectors are also removed from the installed
sys/stat.h header file. The wrapper implementation license LGPL
exception is also removed since it is no longer statically linked to
binaries.
Internally the _STAT_VER* definitions are moved to a arch-specific
xstatver.h file. The internal defines that redirects internals
{f}stat{at} to their {f}xstat{at} counterparts are removed for Linux
(!NO_RTLD_HIDDEN). Hurd still requires them since {f}stat{at} pulls
extra objects that makes the loader build fail otherwise (I haven't
dig into why exactly).
Checked with a build for all affected ABIs. I also checked on x86_64,
i686, powerpc, powerpc64le, sparcv9, sparc64, s390, and s390x.
Reviewed-by: Lukasz Majewski <lukma@denx.de>
This patch adds the ABI-related bits to reflect the new mallinfo2
function, and adds a test case to verify basic functionality.
Reviewed-by: Adhemerval Zanella <adhemerval.zanella@linaro.org>
Linux 5.8 has one new syscall, faccessat2. Update syscall-names.list
and regenerate the arch-syscall.h headers with build-many-glibcs.py
update-syscalls.
Tested with build-many-glibcs.py.
The kernel ABI is not finalized, and there are now various proposals
to change the size of struct rseq, which would make the glibc ABI
dependent on the version of the kernels used for building glibc.
This is of course not acceptable.
This reverts commit 48699da1c4 ("elf:
Support at least 32-byte alignment in static dlopen"), commit
8f4632deb3 ("Linux: rseq registration
tests"), commit 6e29cb3f61 ("Linux: Use
rseq in sched_getcpu if available"), and commit
0c76fc3c2b ("Linux: Perform rseq
registration at C startup and thread creation"), resolving the conflicts
introduced by the ARC port and the TLS static surplus changes.
Reviewed-by: Carlos O'Donell <carlos@redhat.com>
Binaries can opt-in to using BTI via an ELF object file marking.
The dynamic linker has to then mprotect the executable segments
with PROT_BTI. In case of static linked executables or in case
of the dynamic linker itself, PROT_BTI protection is done by the
operating system.
On AArch64 glibc uses PT_GNU_PROPERTY instead of PT_NOTE to check
the properties of a binary because PT_NOTE can be unreliable with
old linkers (old linkers just append the notes of input objects
together and add them to the output without checking them for
consistency which means multiple incompatible GNU property notes
can be present in PT_NOTE).
BTI property is handled in the loader even if glibc is not built
with BTI support, so in theory user code can be BTI protected
independently of glibc. In practice though user binaries are not
marked with the BTI property if glibc has no support because the
static linked libc objects (crt files, libc_nonshared.a) are
unmarked.
This patch relies on Linux userspace API that is not yet in a
linux release but in v5.8-rc1 so scheduled to be in Linux 5.8.
Co-authored-by: Szabolcs Nagy <szabolcs.nagy@arm.com>
Reviewed-by: Adhemerval Zanella <adhemerval.zanella@linaro.org>
setcontext returns to the specified context via an indirect jump,
so there should be a BTI j.
In case of getcontext (and all other returns_twice functions) the
compiler adds BTI j at the call site, but swapcontext is a normal
c call that is currently not handled specially by the compiler.
So we change swapcontext such that the saved context returns to a
local address that has BTI j and then swapcontext returns to the
caller via a normal RET. For this we save the original return
address in the slot for x1 of the context because x1 need not be
preserved by swapcontext but it is restored when the context saved
by swapcontext is resumed.
The alternative fix (which is done on x86) would make swapcontext
special in the compiler so BTI j is emitted at call sites, on
x86 there is an indirect_return attribute for this, on AArch64
we would have to use returns_twice. It was decided against because
such fix may need user code updates: the attribute has to be added
when swapcontext is called via a function pointer and it breaks
always_inline functions with swapcontext.
Reviewed-by: Adhemerval Zanella <adhemerval.zanella@linaro.org>
The strerrorname_np returns error number name (e.g. "EINVAL" for EINVAL)
while strerrordesc_np returns string describing error number (e.g
"Invalid argument" for EINVAL). Different than strerror,
strerrordesc_np does not attempt to translate the return description,
both functions return NULL for an invalid error number.
They should be used instead of sys_errlist and sys_nerr, both are
thread and async-signal safe. These functions are GNU extensions.
Checked on x86-64-linux-gnu, i686-linux-gnu, powerpc64le-linux-gnu,
and s390x-linux-gnu.
Tested-by: Carlos O'Donell <carlos@redhat.com>
Reviewed-by: Carlos O'Donell <carlos@redhat.com>
The sigabbrev_np returns the abbreviated signal name (e.g. "HUP" for
SIGHUP) while sigdescr_np returns the string describing the error
number (e.g "Hangup" for SIGHUP). Different than strsignal,
sigdescr_np does not attempt to translate the return description and
both functions return NULL for an invalid signal number.
They should be used instead of sys_siglist or sys_sigabbrev and they
are both thread and async-signal safe. They are added as GNU
extensions on string.h header (same as strsignal).
Checked on x86-64-linux-gnu, i686-linux-gnu, powerpc64le-linux-gnu,
and s390x-linux-gnu.
Tested-by: Carlos O'Donell <carlos@redhat.com>
Reviewed-by: Carlos O'Donell <carlos@redhat.com>
The variable is placed in libc.so, and it can be true only in
an outer libc, not libcs loaded via dlmopen or static dlopen.
Since thread creation from inner namespaces does not work,
pthread_create can update __libc_single_threaded directly.
Using __libc_early_init and its initial flag, implementation of this
variable is very straightforward. A future version may reset the flag
during fork (but not in an inner namespace), or after joining all
threads except one.
Reviewed-by: DJ Delorie <dj@redhat.com>
