Due to the built-in tables, __NR_mq_getsetattr, __NR_mq_notify,
__NR_mq_open, __NR_mq_timedreceive, __NR_mq_timedsend, __NR_mq_unlink
are always defined.
Reviewed-by: Adhemerval Zanella <adhemerval.zanella@linaro.org>
Writable, executable segments defeat security hardening. The
existing check for DT_TEXTREL does not catch this.
hppa and SPARC currently keep the PLT in an RWX load segment.
It is necessary to export __pthread_cond_init from libc because
the C11 condition variable needs it and is still left in libpthread.
This is part of the libpthread removal project:
<https://sourceware.org/ml/libc-alpha/2019-10/msg00080.html>
Reviewed-by: Adhemerval Zanella <adhemerval.zanella@linaro.org>
It is necessary to export __pthread_cond_destroy from libc because
the C11 condition variable needs it and is still left in libpthread.
This is part of the libpthread removal project:
<https://sourceware.org/ml/libc-alpha/2019-10/msg00080.html>
Reviewed-by: Adhemerval Zanella <adhemerval.zanella@linaro.org>
The behavior of the signal mask on threads created by timer_create
for SIGEV_THREAD timers are implementation-defined and glibc explicit
unblocks all signals before calling the user-defined function.
This behavior, although not incorrect standard-wise, opens a race if a
program using a blocked rt-signal plus sigwaitinfo (and without an
installed signal handler for the rt-signal) receives a signal while
executing the used-defined function for SIGEV_THREAD.
A better alternative discussed in bug report is to rather block all
signals (besides the internal ones not available to application
usage).
This patch fixes this issue by only unblocking SIGSETXID (used on
set*uid function) and SIGCANCEL (used for thread cancellation).
Checked on x86_64-linux-gnu and i686-linux-gnu.
From the GNU C Library manual, the pkey_set can receive a combination of
PKEY_DISABLE_WRITE and PKEY_DISABLE_ACCESS. However PKEY_DISABLE_ACCESS
is more restrictive than PKEY_DISABLE_WRITE and includes its behavior.
The test expects that after setting
(PKEY_DISABLE_WRITE|PKEY_DISABLE_ACCESS) pkey_get should return the
same. This may not be true as PKEY_DISABLE_ACCESS will succeed in
describing the state of the key in this case.
The pkey behavior during signal handling is different between x86 and
POWER. This change make the test compatible with both architectures.
Reviewed-by: Tulio Magno Quites Machado Filho <tuliom@linux.ibm.com>
In the glibc the gettimeofday can use vDSO (on power and x86 the
USE_IFUNC_GETTIMEOFDAY is defined), gettimeofday syscall or 'default'
___gettimeofday() from ./time/gettime.c (as a fallback).
In this patch the last function (___gettimeofday) has been refactored and
moved to ./sysdeps/unix/sysv/linux/gettimeofday.c to be Linux specific.
The new __gettimeofday64 explicit 64 bit function for getting 64 bit time from
the kernel (by internally calling __clock_gettime64) has been introduced.
Moreover, a 32 bit version - __gettimeofday has been refactored to internally
use __gettimeofday64.
The __gettimeofday is now supposed to be used on systems still supporting 32
bit time (__TIMESIZE != 64) - hence the necessary check for time_t potential
overflow and conversion of struct __timeval64 to 32 bit struct timespec.
The iFUNC vDSO direct call optimization has been removed from both i686 and
powerpc32 (USE_IFUNC_GETTIMEOFDAY is not defined for those architectures
anymore). The Linux kernel does not provide a y2038 safe implementation of
gettimeofday neither it plans to provide it in the future, clock_gettime64
should be used instead. Keeping support for this optimization would require
to handle another build permutation (!__ASSUME_TIME64_SYSCALLS &&
USE_IFUNC_GETTIMEOFDAY) which adds more complexity and has limited use
(since the idea is to eventually have a y2038 safe glibc build).
Build tests:
./src/scripts/build-many-glibcs.py glibcs
Run-time tests:
- Run specific tests on ARM/x86 32bit systems (qemu):
https://github.com/lmajewski/meta-y2038 and run tests:
https://github.com/lmajewski/y2038-tests/commits/master
Above tests were performed with Y2038 redirection applied as well as without
to test proper usage of both __gettimeofday64 and __gettimeofday.
Reviewed-by: Adhemerval Zanella <adhemerval.zanella@linaro.org>
[Including some commit message improvement]
It appears that the ability to change symbolic link modes through such
paths is unintended. On several file systems, the operation fails with
EOPNOTSUPP, even though the symbolic link permissions are updated.
The expected behavior is a failure to update the permissions, without
file system changes.
Reviewed-by: Matheus Castanho <msc@linux.ibm.com>
MIPS fallback code handle a frame where its FDE can not be obtained
(for instance a signal frame) by reading the kernel allocated signal frame
and adding '2' to the value of 'sc_pc' [1]. The added value is used to
recognize an end of an EH region on mips16 [2].
The fix adjust the obtained signal frame value and remove the libgcc added
value by checking if the previous frame is a signal frame one.
Checked with backtrace and tst-sigcontext-get_pc tests on mips-linux-gnu
and mips64-linux-gnu.
[1] libgcc/config/mips/linux-unwind.h from gcc code.
[2] gcc/config/mips/mips.h from gcc code. */
The new type struct fd_to_filename makes the allocation of the
backing storage explicit.
Hurd uses /dev/fd, not /proc/self/fd.
Co-Authored-By: Paul Eggert <eggert@cs.ucla.edu>
Exporting functions and relying on symbol interposition from libc.so
makes the choice of implementation dependent on DT_NEEDED order, which
is not what some compiler drivers expect.
This commit replaces one magic mechanism (symbol interposition) with
another one (preprocessor-/compiler-based redirection). This makes
the hand-over from the minimal malloc to the full malloc more
explicit.
Removing the ABI symbols is backwards-compatible because libc.so is
always in scope, and the dynamic loader will find the malloc-related
symbols there since commit f0b2132b35
("ld.so: Support moving versioned symbols between sonames
[BZ #24741]").
Reviewed-by: Carlos O'Donell <carlos@redhat.com>
With all Linux ABIs using the expected Linux kABI to indicate
syscalls errors, the INTERNAL_SYSCALL_DECL is an empty declaration
on all ports.
This patch removes the 'err' argument on INTERNAL_SYSCALL* macro
and remove the INTERNAL_SYSCALL_DECL usage.
Checked with a build against all affected ABIs.
With all Linux ABIs using the expected Linux kABI to indicate
syscalls errors, there is no need to replicate the INLINE_SYSCALL.
The generic Linux sysdep.h includes errno.h even for !__ASSEMBLER__,
which is ok now and it allows cleanup some archaic code that assume
otherwise.
Checked with a build against all affected ABIs.
The riscv INTERNAL_SYSCALL macro might clobber the register
parameter if the argument itself might clobber any register (a function
call for instance).
This patch fixes it by using temporary variables for the expressions
between the register assignments (as indicated by GCC documentation,
6.47.5.2 Specifying Registers for Local Variables).
It is similar to the fix done for MIPS (bug 25523).
Checked with riscv64-linux-gnu-rv64imafdc-lp64d build.
The microblaze INTERNAL_SYSCALL macro might clobber the register
parameter if the argument itself might clobber any register (a function
call for instance).
This patch fixes it by using temporary variables for the expressions
between the register assignments (as indicated by GCC documentation,
6.47.5.2 Specifying Registers for Local Variables).
It is similar to the fix done for MIPS (bug 25523).
Checked with microblaze-linux-gnu and microblazeel-linux-gnu build.
It changes the nios INTERNAL_SYSCALL_RAW macro to return a negative
value instead of the 'r2' register value on the 'err' macro argument.
The macro INTERNAL_SYSCALL_DECL is no longer required, and the
INTERNAL_SYSCALL_ERROR_P macro follows the other Linux kABIs.
Checked with a build against nios2-linux-gnu.
It changes the mips INTERNAL_SYSCALL* and internal_syscall* macros
to return a negative value instead of the 'a3' register value on then
'err' macro argument.
The macro INTERNAL_SYSCALL_DECL is no longer required, and the
INTERNAL_SYSCALL_ERROR_P macro follows the other Linux kABIs.
The redefinition of INTERNAL_VSYSCALL_CALL is also no longer
required.
Checked on mips64-linux-gnu, mips64n32-linux-gnu, and mips-linux-gnu.
The mips64 Linux syscall macros only differs argument type and
the requirement of sign-extending values on n32. The headers
are consolidate by parameterizing the arguments with a new type,
__syscall_arg_t, and by defining the ARGIFY for n64.
Also, the generic unix mips64 sysdep is essentially the same,
only the load instruction need to be adjusted depending of the
ABI.
Checked on mips64-linux-gnu and mips64n32-linux-gnu.
It changes the ia64 INTERNAL_SYSCALL_NCS macro to return a negative
value instead of the 'r10' register value on the 'err' macro argument.
The macro INTERNAL_SYSCALL_DECL is no longer required, and the
INTERNAL_SYSCALL_ERROR_P macro follows the other Linux kABIs.
Checked on ia64-linux-gnu.
It highly unlikely that alpha will be ported to anything else than
Linux, so this patch moves the generic unix syscall definition to
Linux and adapt it to Linux kernel ABI.
It changes the internal_syscall* macros to return a negative value
instead of the '$19' register value on the 'err' macro argument.
The macro INTERNAL_SYSCALL_DECL is no longer required, and the
INTERNAL_SYSCALL_ERROR_P macro follows the other Linux kABIs.
Checked on alpha-linux-gnu.
The sparc INTERNAL_SYSCALL macro might clobber the register
parameter if the argument itself might clobber any register (a function
call for instance).
This patch fixes it by using temporary variables for the expressions
between the register assignments (as indicated by GCC documentation,
6.47.5.2 Specifying Registers for Local Variables).
It is similar to the fix done for MIPS (bug 25523).
Checked on sparc64-linux-gnu and sparcv9-linux-gnu.
It changes the sparc internal_syscall* macros to return a negative
value instead of the 'g1' register value in the 'err' macro argument.
The __SYSCALL_STRING macro is also changed to no set the 'g1'
value, since 'o1' already holds all the required information
to check if syscall has failed.
The macro INTERNAL_SYSCALL_DECL is no longer required, and the
INTERNAL_SYSCALL_ERROR_P macro follows the other Linux kABIs.
The redefinition of INTERNAL_VSYSCALL_CALL is also no longer
required.
Checked on sparc64-linux-gnu and sparcv9-linux-gnu. It fixes
the sporadic issues on sparc32 where clock_nanosleep does not
act as cancellation entrypoint.
It changes the powerpc INTERNAL_VSYSCALL_CALL and INTERNAL_SYSCALL_NCS
to return a negative value instead of the returning the CR value in
the 'err' macro argument.
The macro INTERNAL_SYSCALL_DECL is no longer required, and the
INTERNAL_SYSCALL_ERROR_P macro follows the other Linux kABIs.
Checked on powerpc64-linux-gnu, powerpc64le-linux-gnu, and
powerpc-linux-gnu-power4.
The diferences between powerpc64{le} and powerpc32 Linux sysdep.h
are:
1. On both vDSO and syscall macros the volatile registers r9, r10,
r11, and r12 are used as input operands on powerpc32 and as
clobber registers on powerpc64. However the outcome is essentially
the same, it advertise the register might be clobbered by the
kernel (although Linux won't leak register information to userland
in such case).
2. The LOADARGS* macros uses a different size to check for invalid
types.
3. The pointer mangling support guard pointer loading uses ABI
specific instruction and register.
This patch consolidates on only one sysdep by using the the powerpc64
version as default and add the adjustments required for powerpc32.
Checked on powerpc64-linux-gnu, powerpc64le-linux-gnu, and
powerpc-linux-gnu-power4.
1. getcontext and swapcontext are updated to save the caller's shadow
stack pointer and return address.
2. setcontext and swapcontext are updated to restore shadow stack and
jump to new context directly.
3. makecontext is updated to allocate a new shadow stack and set the
caller's return address to the helper code, L(exitcode).
4. Since we no longer save and restore EAX, ECX and EDX in getcontext,
setcontext and swapcontext, we can use them as scratch register slots
to enable CET in ucontext functions.
Since makecontext allocates a new shadow stack when making a new
context and kernel allocates a new shadow stack for clone/fork/vfork
syscalls, we track the current shadow stack base. In setcontext and
swapcontext, if the target shadow stack base is the same as the current
shadow stack base, we unwind the shadow stack. Otherwise it is a stack
switch and we look for a restore token.
We enable shadow stack at run-time only if program and all used shared
objects, including dlopened ones, are shadow stack enabled, which means
that they must be compiled with GCC 8 or above and glibc 2.28 or above.
We need to save and restore shadow stack only if shadow stack is enabled.
When caller of getcontext, setcontext, swapcontext and makecontext is
compiled with smaller ucontext_t, shadow stack won't be enabled at
run-time. We check if shadow stack is enabled before accessing the
extended field in ucontext_t.
Tested on i386 CET/non-CET machines.
Reviewed-by: Carlos O'Donell <carlos@redhat.com>
We can't include sysdep.h in the test case (it introduces lots of
strange failures) so __NR_futex isn't redifined to __NR_futex_time64 by
64-bit time_t 32-bit archs (y2038 safe).
To allow the test to pass let's just do the __NR_futex_time64 syscall if
we don't have __NR_futex defined.
Reviewed-by: Adhemerval Zanella <adhemerval.zanella@linaro.org>
The 32-bit protection key behavior is somewhat unclear on 32-bit powerpc,
so this change is restricted to the 64-bit variants.
Flag translation is needed because of hardware differences between the
POWER implementation (read and write flags) and the Intel implementation
(write and read+write flags).
A non-ascii character in the installed headers leads now to:
error: failure to convert ascii to UTF-8
Such a finding in s390 specific fenv.h leads to fails in GCC testsuite.
See glibc commit 08aea89ef6.
Adding this gcc option also to our tests was proposed by Florian Weimer.
This change also found a hit in resource.h where now "microseconds" is used.
I've adjusted all the resource.h files.
I've used the following command to check for further hits in headers.
LC_ALL=C find -name "*.h" -exec grep -PHn "[\x80-\xFF]" {} \;
Tested on s390x and x86_64.
Reviewed-by: Zack Weinberg <zackw@panix.com>
By undef strong_alias on alpha implementation, the
default_symbol_version macro becomes an empty macro on static build.
It fixes the issue introduced at c953219420.
Checked on alpha-linux-gnu with a 'make check run-built-tests=no'.
According to [gcc documentation][1], temporary variables must be used for
the desired content to not be call-clobbered.
Fix the Linux inline syscall templates by adding temporary variables,
much like what x86 did before
(commit 381a0c26d7).
Tested with gcc 9.2.0, both cross-compiled and natively on Loongson
3A4000.
[1]: https://gcc.gnu.org/onlinedocs/gcc/Local-Register-Variables.html
It makes alpha no longer reports information about a system-wide
time zone and moves the version logic on the alpha implementation.
Checked on a build and check-abi for alpha-linux-gnu.
Reviewed-by: Lukasz Majewski <lukma@denx.de>
Linux 5.5 renames RWF_WRITE_LIFE_NOT_SET to RWH_WRITE_LIFE_NOT_SET,
with the old name kept as an alias. This patch makes the
corresponding change in glibc.
Tested for x86_64.
The O_PATH-based fchmodat emulation will rely on the fact that closing
an O_PATH descriptor never releases POSIX advisory locks, so this
commit adds a test case for this behavior.
This patch provides new __settimeofday64 explicit 64 bit function for setting
64 bit time in the kernel (by internally calling __clock_settime64).
Moreover, a 32 bit version - __settimeofday has been refactored to internally
use __settimeofday64.
The __settimeofday is now supposed to be used on systems still supporting 32
bit time (__TIMESIZE != 64) - hence the necessary conversion of struct
timeval to 64 bit struct __timespec64.
Internally the settimeofday uses __settimeofday64. This patch is necessary
for having architectures with __WORDSIZE == 32 Y2038 safe.
Build tests:
./src/scripts/build-many-glibcs.py glibcs
Run-time tests:
- Run specific tests on ARM/x86 32bit systems (qemu):
https://github.com/lmajewski/meta-y2038 and run tests:
https://github.com/lmajewski/y2038-tests/commits/master
Above tests were performed with Y2038 redirection applied as well as without
to test proper usage of both __settimeofday64 and __settimeofday.
Reviewed-by: Adhemerval Zanella <adhemerval.zanella@linaro.org>
The name 'valid_timeval64_to_timeval' suggest conversion of struct
__timeval64 to struct timeval (as in ./include/time.h).
As on the alpha the struct timeval supports 64 bit time, it seems more
feasible to emphasis struct timeval32 in the conversion function name.
Hence the helper function naming change to 'valid_timeval_to_timeval32'.
Build tests:
./src/scripts/build-many-glibcs.py glibcs
Reviewed-by: Alistair Francis <alistair.francis@wdc.com>
Reviewed-by: Adhemerval Zanella <adhemerval.zanella@linaro.org>
Without this patch the naming convention for functions to convert
struct timeval32 to struct timeval (which supports 64 bit time on Alpha) was
a bit misleading. The name 'valid_timeval_to_timeval64' suggest conversion
of struct timeval to struct __timeval64 (as in ./include/time.h).
As on alpha the struct timeval supports 64 bit time it seems more readable
to emphasis struct timeval32 in the conversion function name.
Hence the helper function naming change to 'valid_timeval32_to_timeval'.
Build tests:
./src/scripts/build-many-glibcs.py glibcs
Reviewed-by: Alistair Francis <alistair.francis@wdc.com>
Reviewed-by: Adhemerval Zanella <adhemerval.zanella@linaro.org>
The __suseconds64_t type is supposed to be the 64 bit type across all
architectures.
It would be mostly used internally in the glibc - however, when passed to
Linux kernel (very unlikely), if necessary, it shall be converted to 32
bit type (i.e. __suseconds_t)
Build tests:
./src/scripts/build-many-glibcs.py glibcs
Reviewed-by: Alistair Francis <alistair.francis@wdc.com>
Reviewed-by: Adhemerval Zanella <adhemerval.zanella@linaro.org>
This patch updates the kernel version in the test tst-mman-consts.py
to 5.5. (There are no new constants covered by this test in 5.5 that
need any other header changes.)
Tested with build-many-glibcs.py.
Linux 5.5 has no new syscalls to add to syscall-names.list, but it
does newly enable the clone3 syscall for AArch64. This patch updates
the kernel version listed in syscall-names.list and regenerates the
AArch64 arch-syscall.h.
Tested with build-many-glibcs.py.
This patch provides new instance of Linux specific timespec_get.c file placed
in ./sysdeps/unix/sysv/linux/.
When compared to this file version from ./time directory, it provides
__timespec_get64 explicit 64 bit function for getting 64 bit time in the
struct __timespec64 (for compilation using C11 standard).
Moreover, a 32 bit version - __timespec_get internally uses
__timespec_get64.
The __timespec_get is now supposed to be used on systems still supporting 32
bit time (__TIMESIZE != 64) - hence the necessary conversion to 32 bit struct
timespec.
Internally the timespec_get uses __clock_gettime64. This patch is necessary
for having architectures with __WORDSIZE == 32 Y2038 safe.
Build tests:
./src/scripts/build-many-glibcs.py glibcs
Run-time tests:
- Run specific tests on ARM/x86 32bit systems (qemu):
https://github.com/lmajewski/meta-y2038 and run tests:
https://github.com/lmajewski/y2038-tests/commits/master
Above tests were performed with Y2038 redirection applied as well as without
to test proper usage of both __timespec_get64 and __timespec_get.
Reviewed-by: Adhemerval Zanella <adhemerval.zanella@linaro.org>
The functions __timer_gettime64 and __timer_settime64 live in librt, not
libc. Use proper hidden aliases so that the callers do not need to set up
the PLT register.
Fixes commits cae1635a70 ("y2038: linux: Provide __timer_settime64
implementation") and 562cdc19c7 ("y2038: linux: Provide __timer_gettime64
implementation").
This patch replaces auto generated wrapper (as described in
sysdeps/unix/sysv/linux/syscalls.list) for sched_rr_get_interval with one which
adds extra support for reading 64 bit time values on machines with
__TIMESIZE != 64.
There is no functional change for architectures already supporting 64 bit
time ABI.
The sched_rr_get_interval declaration in ./include/sched.h is not followed by
corresponding libc_hidden_proto(), so it has been assumed that newly introduced
syscall wrapper doesn't require libc_hidden_def() (which has been added by
template used with auto generation script).
Moreover, the code for building sched_rr_gi.c file is already placed in
./posix/Makefiles, so there was no need to add it elsewhere.
Performed tests and validation are the same as for timer_gettime() conversion
(sysdeps/unix/sysv/linux/timer_gettime.c).
Reviewed-by: Adhemerval Zanella <adhemerval.zanella@linaro.org>
This patch replaces auto generated wrapper (as described in
sysdeps/unix/sysv/linux/syscalls.list) for timerfd_settime with one which
adds extra support for reading and writing from Linux kernel 64 bit time
values on machines with __TIMESIZE != 64.
There is no functional change for archs already supporting 64 bit time ABI.
This patch is conceptually identical to timer_settime conversion already
done in sysdeps/unix/sysv/linux/timer_settime.c.
Please refer to corresponding commit message for detailed description of
introduced functions and the testing procedure.
Reviewed-by: Adhemerval Zanella <adhemerval.zanella@linaro.org>
---
Changes for v4:
- Update date from 2019 to 2020
Changes for v3:
- Add missing libc_hidden_def()
Changes for v2:
- Remove "Contributed by" from the file header
- Remove early check for (fd < 0) in __timerfd_settime64 as the fd
correctness check is already done in Linux kernel
- Add single descriptive comment line to provide concise explanation
of the code
This patch replaces auto generated wrapper (as described in
sysdeps/unix/sysv/linux/syscalls.list) for timerfd_gettime with one which
adds extra support for reading 64 bit time values on machines with
__TIMESIZE != 64.
There is no functional change for architectures already supporting 64 bit
time ABI.
This patch is conceptually identical to timer_gettime conversion already
done in sysdeps/unix/sysv/linux/timer_gettime.c.
Please refer to corresponding commit message for detailed description of
introduced functions and the testing procedure.
Reviewed-by: Adhemerval Zanella <adhemerval.zanella@linaro.org>
---
Changes for v4:
- Update date from 2019 to 2020
Changes for v3:
- Add missing libc_hidden_def()
Changes for v2:
- Remove "Contributed by" from the file header
- Remove early check for (fd < 0) in __timerfd_gettime64 as the fd
correctness check is already done in Linux kernel
- Add single descriptive comment line to provide concise explanation
of the code
The generic implementation is suffice since __NR_exit_group is always
support and i386 does define ABORT_INSTRUCTION.
Reviewed-by: Adhemerval Zanella <adhemerval.zanella@linaro.org>
On i386, since EAX, ECX and EDX are caller-saved, there are no need
to save and restore EAX, ECX and EDX in getcontext, setcontext and
swapcontext. They just need to clear EAX on success. The extra
scratch registers are needed to enable CET.
Tested on i386.
Reviewed-by: Adhemerval Zanella <adhemerval.zanella@linaro.org>
This test was failing in some powerpc systems as it was not checking
for ENOSPC return.
As said on the Linux man-pages and can be observed by the implementation
at mm/mprotect.c in the Linux Kernel source. The syscall pkey_alloc can
return EINVAL or ENOSPC. ENOSPC will indicate either that all keys are
in use or that the kernel does not support pkeys.
Reviewed-by: Gabriel F. T. Gomes <gabriel@inconstante.net.br>
GCC 10.0 enabled -fno-common by default and this started to point that
__cache_line_size had been implemented in 2 different places: loader and
libc.
In order to avoid this duplication, the libc variable has been removed
and the loader variable is moved to rtld_global_ro.
File sysdeps/unix/sysv/linux/powerpc/dl-auxv.h has been added in order
to reuse code for both static and dynamic linking scenarios.
Reviewed-by: Carlos O'Donell <carlos@redhat.com>
Initialize dl_auxv, dl_hwcap and dl_hwcap2 in rtld_global_ro for DSOs
that have been statically dlopen'ed.
Reviewed-by: Carlos O'Donell <carlos@redhat.com>
This patch avoid probing the __NR_clock_getttime64 syscall each time
__clock_gettime64 is issued on a kernel without 64 bit time support.
Once ENOSYS is obtained, only 32-bit clock_gettime are used.
The following snippet:
clock_getres (CLOCK_REALTIME, &(struct timespec) { 0 });
clock_getres (CLOCK_MONOTONIC, &(struct timespec) { 0 });
clock_getres (CLOCK_BOOTTIME, &(struct timespec) { 0 });
clock_getres (20, &(struct timespec) { 0 });
On a kernel without 64 bit time support issues the syscalls:
syscall_0x196(0, 0xffb83330, [...]) = -1 ENOSYS (Function not implemented)
clock_getres(CLOCK_REALTIME, {tv_sec=0, tv_nsec=1}) = 0
clock_getres(CLOCK_MONOTONIC, {tv_sec=0, tv_nsec=1}) = 0
clock_getres(CLOCK_BOOTTIME, {tv_sec=0, tv_nsec=1}) = 0
Checked on i686-linux-gnu on 4.15 kernel.
Reviewed-by: Siddhesh Poyarekar <siddhesh@sourceware.org>
No architecture currently defines the vDSO symbol. On archictures
with 64-bit time_t the HAVE_CLOCK_GETRES_VSYSCALL is renamed to
HAVE_CLOCK_GETRES64_VSYSCALL, it simplifies clock_gettime code.
Reviewed-by: Siddhesh Poyarekar <siddhesh@sourceware.org>
It was added on Linux 5.3 (commit 22ca962288c0a).
Checked on i686-linux-gnu with 5.3.0 kernel.
Reviewed-by: Siddhesh Poyarekar <siddhesh@sourceware.org>
This patch avoid probing the __NR_clock_getttime64 syscall each time
__clock_gettime64 is issued on a kernel without 64 bit time support.
Once ENOSYS is obtained, only 32-bit clock_gettime are used.
The following snippet:
clock_gettime (CLOCK_REALTIME, &(struct timespec) { 0 });
clock_gettime (CLOCK_MONOTONIC, &(struct timespec) { 0 });
clock_gettime (CLOCK_BOOTTIME, &(struct timespec) { 0 });
clock_gettime (20, &(struct timespec) { 0 });
On a kernel without 64 bit time support and with vDSO support results
on the following syscalls:
syscall_0x193(0, 0xff87ba30, [...]) = -1 ENOSYS (Function not implemented)
clock_gettime(CLOCK_BOOTTIME, {tv_sec=927082, tv_nsec=474382032}) = 0
clock_gettime(0x14 /* CLOCK_??? */, 0xff87b9f8) = -1 EINVAL (Invalid argument)
While on a kernel without vDSO support:
syscall_0x193(0, 0xbec95550, 0xb6ed2000, 0x1, 0xbec95550, 0) = -1 (errno 38)
clock_gettime(CLOCK_REALTIME, {tv_sec=1576615930, tv_nsec=638250162}) = 0
clock_gettime(CLOCK_MONOTONIC, {tv_sec=1665478, tv_nsec=638779620}) = 0
clock_gettime(CLOCK_BOOTTIME, {tv_sec=1675418, tv_nsec=292932704}) = 0
clock_gettime(0x14 /* CLOCK_??? */, 0xbec95530) = -1 EINVAL (Invalid argument)
Checked on i686-linux-gnu on 4.15 kernel and on a 5.3 kernel.
Reviewed-by: Siddhesh Poyarekar <siddhesh@sourceware.org>
No architecture currently defines the vDSO symbol. On architectures
with 64-bit time_t the HAVE_CLOCK_GETTIME_VSYSCALL is renamed to
HAVE_CLOCK_GETTIME64_VSYSCALL, it simplifies clock_gettime code.
Reviewed-by: Siddhesh Poyarekar <siddhesh@sourceware.org>
This patch moves the vDSO setup from libc to loader code, just after
the vDSO link_map setup. For static case the initialization
is moved to _dl_non_dynamic_init instead.
Instead of using the mangled pointer, the vDSO data is set as
attribute_relro (on _rtld_global_ro for shared or _dl_vdso_* for
static). It is read-only even with partial relro.
It fixes BZ#24967 now that the vDSO pointer is setup earlier than
malloc interposition is called.
Also, vDSO calls should not be a problem for static dlopen as
indicated by BZ#20802. The vDSO pointer would be zero-initialized
and the syscall will be issued instead.
Checked on x86_64-linux-gnu, i686-linux-gnu, aarch64-linux-gnu,
arm-linux-gnueabihf, powerpc64le-linux-gnu, powerpc64-linux-gnu,
powerpc-linux-gnu, s390x-linux-gnu, sparc64-linux-gnu, and
sparcv9-linux-gnu. I also run some tests on mips.
Reviewed-by: Siddhesh Poyarekar <siddhesh@sourceware.org>
The IFUNC bypass to vDSO is used when USE_IFUNC_TIME is set.
Currently powerpc and x86 defines it. Otherwise the generic
implementation is used, which calls clock_gettime.
Checked on powerpc64le-linux-gnu, powerpc64-linux-gnu,
powerpc-linux-gnu-power4, x86_64-linux-gnu, and i686-linux-gnu.
Reviewed-by: Siddhesh Poyarekar <siddhesh@sourceware.org>
The IFUNC bypass to vDSO is used when USE_IFUNC_GETTIMEOFDAY is set.
Currently aarch64, powerpc*, and x86 defines it. Otherwise the
generic implementation is used, which calls clock_gettime.
Checked on aarch64-linux-gnu, powerpc64le-linux-gnu,
powerpc64-linux-gnu, powerpc-linux-gnu-power4, x86_64-linux-gnu,
and i686-linux-gnu.
Reviewed-by: Siddhesh Poyarekar <siddhesh@sourceware.org>
The clock_getres is a new implementation added on Linux 5.4
(abed3d826f2f).
Checked with a build against mips-linux-gnu and mips64-linux-gnu.
Reviewed-by: Siddhesh Poyarekar <siddhesh@sourceware.org>
Add the missing time and clock_getres vDSO symbol names on x86.
For time, the iFUNC already uses expected name so it affects only
the static build.
The clock_getres is a new implementation added on Linux 5.3
(f66501dc53e72).
Checked on x86-linux-gnu and i686-linux-gnu.
Reviewed-by: Siddhesh Poyarekar <siddhesh@sourceware.org>
The auto-generated vDSO call shows some issues:
- It requires sync the auto-generated C file with current glibc
implementation;
- It still uses symbol redirections hacks where libc-symbols.h
provide macros that uses compiler builtins
(libc_ifunc_redirected for instance);
- It does not handle all required compiler handling
(inhibit_stack_protector on iFUNC resolver).
- No architecure uses it.
Checked with a build against all major ABIs.
Reviewed-by: Siddhesh Poyarekar <siddhesh@sourceware.org>
This is the only use of auto-generation syscall which uses a vDSO
plus IFUNC and the current x86 generic implementation already covers
the expected semantic.
Checked on x86_64-linux-gnu-x32.
Reviewed-by: Siddhesh Poyarekar <siddhesh@sourceware.org>
As indicated on libc-help [1] the ec138c67cb commit broke 32-bit
builds when configured with --enable-kernel=5.1 or higher. The
scenario 10 from [2] might also occur in this configuration and
INLINE_VSYSCALL will try to use the vDSO symbol and
HAVE_CLOCK_GETTIME64_VSYSCALL does not set HAVE_VSYSCALL prior its
usage.
Also, there is no easy way to just enable the code to use one
vDSO symbol since the macro INLINE_VSYSCALL is redefined if
HAVE_VSYSCALL is set.
Instead of adding more pre-processor handling and making the code
even more convoluted, this patch removes the requirement of defining
HAVE_VSYSCALL before including sysdep-vdso.h to enable vDSO usage.
The INLINE_VSYSCALL is now expected to be issued inside a
HAVE_*_VSYSCALL check, since it will try to use the internal vDSO
pointers.
Both clock_getres and clock_gettime vDSO code for time64_t were
removed since there is no vDSO setup code for the symbol (an
architecture can not set HAVE_CLOCK_GETTIME64_VSYSCALL).
Checked on i686-linux-gnu (default and with --enable-kernel=5.1),
x86_64-linux-gnu, aarch64-linux-gnu, and powerpc64le-linux-gnu.
I also checked against a build to mips64-linux-gnu and
sparc64-linux-gnu.
[1] https://sourceware.org/ml/libc-help/2019-12/msg00014.html
[2] https://sourceware.org/ml/libc-alpha/2019-12/msg00142.html
Reviewed-by: Siddhesh Poyarekar <siddhesh@sourceware.org>
The result of INTERNAL_SYSCALL_CANCEL should be checked with
macros INTERNAL_SYSCALL_ERROR_P and INTERNAL_SYSCALL_ERRNO instead
of comparing the result directly.
Checked on powerpc-linux-gnu.
Since the switch away from auto-generated wrappers for these system
calls, the kludge is already included in the C source file of the
system call wrapper.
Use <arch-syscall.h> instead of <asm/unistd.h> to obtain the system
call numbers. A few direct includes of <asm/unistd.h> need to be
removed (if the system call numbers are already provided indirectly
by <sysdep.h>) or replaced with <sys/syscall.h>.
Current Linux headers for alpha define the required system call names,
so most of the _NR_* hacks are no longer needed. For the 32-bit arm
architecture, eliminate the INTERNAL_SYSCALL_ARM macro, now that we
have regular system call names for cacheflush and set_tls. There are
more such cleanup opportunities for other architectures, but these
cleanups are required to avoid macro redefinition errors during the
build.
For ia64, it is desirable to use <asm/break.h> directly to obtain
the break number for system calls (which is not a system call number
itself). This requires replacing __BREAK_SYSCALL with
__IA64_BREAK_SYSCALL because the former is defined as an alias in
<asm/unistd.h>, but not in <asm/break.h>.
Reviewed-by: Siddhesh Poyarekar <siddhesh@sourceware.org>
The new tables are currently only used for consistency checks
with the installed kernel headers and the architecture-independent
system call names table. They are based on Linux 5.4.
The goal is to use these architecture-specific tables to ensure
that system call wrappers are available irrespective of the version
of the installed kernel headers.
The tables are formatted in the form of C header files so that they
can be used directly in an #include directive, without external
preprocessing. (External preprocessing of a plain table file
would introduce cross-subdirectory dependency issues.) However,
the intent is that they can still be treated as tables and can be
processed by simple tools.
The irregular system call names on 32-bit arm add a complication.
The <fixup-asm-unistd.h> header is introduced to work around that,
and the system calls are listed under regular names in the
<arch-syscall.h> file.
A make target, update-syscalls-list, is added to patch the glibc
sources with data from the current kernel headers.
Reviewed-by: Siddhesh Poyarekar <siddhesh@sourceware.org>
I've updated copyright dates in glibc for 2020. This is the patch for
the changes not generated by scripts/update-copyrights and subsequent
build / regeneration of generated files. As well as the usual annual
updates, mainly dates in --version output (minus libc.texinfo which
previously had to be handled manually but is now successfully updated
by update-copyrights), there is a fix to
sysdeps/unix/sysv/linux/powerpc/bits/termios-c_lflag.h where a typo in
the copyright notice meant it failed to be updated automatically.
Please remember to include 2020 in the dates for any new files added
in future (which means updating any existing uncommitted patches you
have that add new files to use the new copyright dates in them).
On platforms where long double has IEEE binary128 format as a third
option (initially, only powerpc64le), many exported functions are
redirected to their __*ieee128 equivalents. This redirection is
provided by installed headers such as stdio-ldbl.h, and is supposed to
work correctly with user code.
However, during the build of glibc, similar redirections are employed,
in internal headers, such as include/stdio.h, in order to avoid extra
PLT entries. These redirections conflict with the redirections to
__*ieee128, and must be avoided during the build. This patch protects
the second redirections with a test for __LONG_DOUBLE_USES_FLOAT128, a
new macro that is defined to 1 when functions that deal with long double
typed values reuses the _Float128 implementation (this is currently only
true for powerpc64le).
Tested for powerpc64le, x86_64, and with build-many-glibcs.py.
Co-authored-by: Gabriel F. T. Gomes <gabrielftg@linux.ibm.com>
Reviewed-by: Florian Weimer <fweimer@redhat.com>
All architectures now uses the Linux generic implementation which
uses __NR_rt_sigprocmask.
Checked on x86_64-linux-gnu, sparc64-linux-gnu, ia64-linux-gnu,
s390x-linux-gnu, and alpha-linux-gnu.
The functions do not fail regardless of the argument value. Also, for
Linux the return value is not correct on some platforms due the missing
usage of INTERNAL_SYSCALL_ERROR_P / INTERNAL_SYSCALL_ERRNO macros.
Checked on x86_64-linux-gnu, i686-linux-gnu, and sparc64-linux-gnu.
Kunpeng processer is a 64-bit Arm-compatible CPU released by Huawei,
and we have already signed a copyright assignement with the FSF.
This patch adds its to cpu list, and related macro for IFUNC.
Checked on aarch64-linux-gnu.
Reviewed-by: Szabolcs Nagy <Szabolcs.Nagy@arm.com>
If the wait4 syscall is not available (such as y2038 safe 32-bit
systems) waitid should be used instead. However prior Linux 5.4
waitid is not a full superset of other wait syscalls, since it
does not include support for waiting for the current process group.
It is possible to emulate wait4 by issuing an extra syscall to get
the current process group, but it is inherent racy: after the current
process group is received and before it is passed to waitid a signal
could arrive causing the current process group to change.
So waitid is used if wait4 is not defined iff the build is
enabled with a minimum kernel if 5.4+. The new assume
__ASSUME_WAITID_PID0_P_PGID is added and an error is issued if waitid
can not be implemented by either __NR_wait4 or
__NR_waitid && __ASSUME_WAITID_PID0_P_PGID.
Checked on x86_64-linux-gnu and i686-linux-gnu.
Co-authored-by: Alistair Francis <alistair.francis@wdc.com>
The POSIX implementation is used as default and both BSD and Linux
version are removed. It simplifies the implementation for
architectures that do not provide either __NR_waitpid or
__NR_wait4.
Checked on x86_64-linux-gnu and powerpc64le-linux-gnu.
