When compiled as mempcpy, the return value is the end of the destination
buffer, thus it cannot be used to refer to the start of it.
(cherry picked from commit 9aaaab7c6e)
On s390 (31bit) if glibc is build with -Os, pthread_join sometimes
blocks indefinitely. This is e.g. observable with
testcase intl/tst-gettext6.
pthread_join is calling lll_wait_tid(tid), which performs the futex-wait
syscall in a loop as long as tid != 0 (thread is alive).
On s390 (and build with -Os), tid is loaded from memory before
comparing against zero and then the tid is loaded a second time
in order to pass it to the futex-wait-syscall.
If the thread exits in between, then the futex-wait-syscall is
called with the value zero and it waits until a futex-wake occurs.
As the thread is already exited, there won't be a futex-wake.
In lll_wait_tid, the tid is stored to the local variable __tid,
which is then used as argument for the futex-wait-syscall.
But unfortunately the compiler is allowed to reload the value
from memory.
With this patch, the tid is loaded with atomic_load_acquire.
Then the compiler is not allowed to reload the value for __tid from memory.
ChangeLog:
[BZ #23137]
* sysdeps/nptl/lowlevellock.h (lll_wait_tid):
Use atomic_load_acquire to load __tid.
(cherry picked from commit 1660901840)
This patch adds the PTRACE_SECCOMP_GET_METADATA constant from Linux
4.16 to all relevant sys/ptrace.h files. A type struct
__ptrace_seccomp_metadata, analogous to other such types, is also
added.
Tested for x86_64, and with build-many-glibcs.py.
* sysdeps/unix/sysv/linux/sys/ptrace.h
(PTRACE_SECCOMP_GET_METADATA): New enum value and macro.
* sysdeps/unix/sysv/linux/bits/ptrace-shared.h
(struct __ptrace_seccomp_metadata): New type.
* sysdeps/unix/sysv/linux/aarch64/sys/ptrace.h
(PTRACE_SECCOMP_GET_METADATA): Likewise.
* sysdeps/unix/sysv/linux/arm/sys/ptrace.h
(PTRACE_SECCOMP_GET_METADATA): Likewise.
* sysdeps/unix/sysv/linux/ia64/sys/ptrace.h
(PTRACE_SECCOMP_GET_METADATA): Likewise.
* sysdeps/unix/sysv/linux/powerpc/sys/ptrace.h
(PTRACE_SECCOMP_GET_METADATA): Likewise.
* sysdeps/unix/sysv/linux/s390/sys/ptrace.h
(PTRACE_SECCOMP_GET_METADATA): Likewise.
* sysdeps/unix/sysv/linux/sparc/sys/ptrace.h
(PTRACE_SECCOMP_GET_METADATA): Likewise.
* sysdeps/unix/sysv/linux/tile/sys/ptrace.h
(PTRACE_SECCOMP_GET_METADATA): Likewise.
* sysdeps/unix/sysv/linux/x86/sys/ptrace.h
(PTRACE_SECCOMP_GET_METADATA): Likewise.
(cherry picked from commit 9320ca88a1)
When there is no login uid Linux sets /proc/self/loginid to the sentinel
value of, (uid_t) -1. If this is set we can return early and avoid
needlessly looking up the sentinel value in any configured nss
databases.
Checked on aarch64-linux-gnu.
* sysdeps/unix/sysv/linux/getlogin_r.c (__getlogin_r_loginuid): Return
early when linux sentinel value is set.
Reviewed-by: Adhemerval Zanella <adhemerval.zanella@linaro.org>
(cherry picked from commit cc8a1620eb)
The RISC-V kernel doesn't define SA_RESTORER, hence the kernel version
of struct sigaction doesn't have the sa_restorer field. The default
kernel_sigaction.h therefore can't be used.
This patch adds a RISC-V specific version of kernel_sigaction.h to fix
the issue. This fixes for example the libnih testsuite.
Note that this patch is not needed in master as the bug has been fixed
by commit b4a5d26d88 ("linux: Consolidate sigaction implementation").
This patch fixes the i386 sa_restorer field initialization for sigaction
syscall for kernel with vDSO. As described in bug report, i386 Linux
(and compat on x86_64) interprets SA_RESTORER clear with nonzero
sa_restorer as a request for stack switching if the SS segment is 'funny'.
This means that anything that tries to mix glibc's signal handling with
segmentation (for instance through modify_ldt syscall) is randomly broken
depending on what values lands in sa_restorer.
The testcase added is based on Linux test tools/testing/selftests/x86/ldt_gdt.c,
more specifically in do_multicpu_tests function. The main changes are:
- C11 atomics instead of plain access.
- Remove x86_64 support which simplifies the syscall handling and fallbacks.
- Replicate only the test required to trigger the issue.
Checked on i686-linux-gnu.
[BZ #21269]
* sysdeps/unix/sysv/linux/i386/Makefile (tests): Add tst-bz21269.
* sysdeps/unix/sysv/linux/i386/sigaction.c (SET_SA_RESTORER): Clear
sa_restorer for vDSO case.
* sysdeps/unix/sysv/linux/i386/tst-bz21269.c: New file.
(cherry picked from commit 68448be208)
Linux ptrace headers define macros whose tokens conflict with the
constants of enum __ptrace_request causing build errors when
asm/ptrace.h or linux/ptrace.h are included before sys/ptrace.h.
* sysdeps/unix/sysv/linux/powerpc/sys/ptrace.h: Undefine Linux
macros used in __ptrace_request.
Signed-off-by: Tulio Magno Quites Machado Filho <tuliom@linux.vnet.ibm.com>
(cherry picked from commit 398c6fddaf)
On sparc32 tst-makecontext fails, as backtrace called within a context
created by makecontext to yield infinite backtrace.
Fix that the same way than nios2 by adding a nop just before
__startcontext. This is needed as otherwise FDE lookup just repeatedly
finds __setcontext's FDE in an infinite loop, due to the convention of
using 'address - 1' for FDE lookup.
Changelog:
[BZ #22919]
* sysdeps/unix/sysv/linux/sparc/sparc32/setcontext.S (__startcontext):
Add nop before __startcontext, add explaining comments.
(cherry picked from commit 9aa5c222b9)
Some SPE opcodes clashes with some recent PowerISA opcodes and
until recently gas did not complain about it. However binutils
recently changed it and now VLE configured gas does not support to
assembler some instruction that might class with VLE (HTM for
instance). It also does not help that glibc build hardware lock
elision support as default (regardless of assembler support).
Although runtime will not actually enables TLE on SPE hardware
(since kernel will not advertise it), I see little advantage on
adding HTM support on SPE built glibc. SPE uses an incompatible
ABI which does not allow share the same build with default
powerpc and HTM code slows down SPE without any benefict.
This patch fixes it by only building HTM when SPE configuration
is not used.
Checked with a powerpc-linux-gnuspe build. I also did some sniff
tests on a e500 hardware without any issue.
[BZ #22926]
* sysdeps/powerpc/powerpc32/sysdep.h (ABORT_TRANSACTION_IMPL): Define
empty for __SPE__.
* sysdeps/powerpc/sysdep.h (ABORT_TRANSACTION): Likewise.
* sysdeps/unix/sysv/linux/powerpc/elision-lock.c (__lll_lock_elision):
Do not build hardware transactional code for __SPE__.
* sysdeps/unix/sysv/linux/powerpc/elision-trylock.c
(__lll_trylock_elision): Likewise.
* sysdeps/unix/sysv/linux/powerpc/elision-unlock.c
(__lll_unlock_elision): Likewise.
Cherry-pick from e921c89e01.
Remove compat-specific constants that were never exported by kernel
headers under these names. Before linux commit v3.7-rc1~16^2~1 they
were exported with COMPAT_ prefix, and since that commit they are not
exported at all.
* sysdeps/unix/sysv/linux/aarch64/sys/ptrace.h (__ptrace_request):
Remove arm-specific PTRACE_GET_THREAD_AREA, PTRACE_GETHBPREGS,
and PTRACE_SETHBPREGS.
(cherry picked from commit 2fd4bbaa14)
When ldconfig reads Elf64 files to determine the ABI, it used the
Elf32 type, so read the wrong location, and stored the wrong ABI
type in the cache, making the cache useless. This patch uses
an Elf64 type for Elf64 objects instead.
Note that pre-patch caches might need to be manually removed and
regenerated to get the correct ABIs stored.
[BZ #22827]
* sysdeps/unix/sysv/linux/riscv/readelflib.c (process_elf_file): Use
64-bit ELF type for 64-bit ELF objects.
(cherry picked from commit 6a1ff640dc)
