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5a82c74822
Also, change sources.redhat.com to sourceware.org.
This patch was automatically generated by running the following shell
script, which uses GNU sed, and which avoids modifying files imported
from upstream:
sed -ri '
s,(http|ftp)(://(.*\.)?(gnu|fsf|sourceware)\.org($|[^.]|\.[^a-z])),https\2,g
s,(http|ftp)(://(.*\.)?)sources\.redhat\.com($|[^.]|\.[^a-z]),https\2sourceware.org\4,g
' \
$(find $(git ls-files) -prune -type f \
! -name '*.po' \
! -name 'ChangeLog*' \
! -path COPYING ! -path COPYING.LIB \
! -path manual/fdl-1.3.texi ! -path manual/lgpl-2.1.texi \
! -path manual/texinfo.tex ! -path scripts/config.guess \
! -path scripts/config.sub ! -path scripts/install-sh \
! -path scripts/mkinstalldirs ! -path scripts/move-if-change \
! -path INSTALL ! -path locale/programs/charmap-kw.h \
! -path po/libc.pot ! -path sysdeps/gnu/errlist.c \
! '(' -name configure \
-execdir test -f configure.ac -o -f configure.in ';' ')' \
! '(' -name preconfigure \
-execdir test -f preconfigure.ac ';' ')' \
-print)
and then by running 'make dist-prepare' to regenerate files built
from the altered files, and then executing the following to cleanup:
chmod a+x sysdeps/unix/sysv/linux/riscv/configure
# Omit irrelevant whitespace and comment-only changes,
# perhaps from a slightly-different Autoconf version.
git checkout -f \
sysdeps/csky/configure \
sysdeps/hppa/configure \
sysdeps/riscv/configure \
sysdeps/unix/sysv/linux/csky/configure
# Omit changes that caused a pre-commit check to fail like this:
# remote: *** error: sysdeps/powerpc/powerpc64/ppc-mcount.S: trailing lines
git checkout -f \
sysdeps/powerpc/powerpc64/ppc-mcount.S \
sysdeps/unix/sysv/linux/s390/s390-64/syscall.S
# Omit change that caused a pre-commit check to fail like this:
# remote: *** error: sysdeps/sparc/sparc64/multiarch/memcpy-ultra3.S: last line does not end in newline
git checkout -f sysdeps/sparc/sparc64/multiarch/memcpy-ultra3.S
60 lines
2.2 KiB
C
60 lines
2.2 KiB
C
/* System-specific malloc support functions. Linux version.
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Copyright (C) 2012-2019 Free Software Foundation, Inc.
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This file is part of the GNU C Library.
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The GNU C Library is free software; you can redistribute it and/or
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modify it under the terms of the GNU Lesser General Public
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License as published by the Free Software Foundation; either
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version 2.1 of the License, or (at your option) any later version.
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The GNU C Library is distributed in the hope that it will be useful,
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but WITHOUT ANY WARRANTY; without even the implied warranty of
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MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
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Lesser General Public License for more details.
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You should have received a copy of the GNU Lesser General Public
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License along with the GNU C Library; if not, see
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<https://www.gnu.org/licenses/>. */
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#include <fcntl.h>
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#include <not-cancel.h>
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/* The Linux kernel overcommits address space by default and if there is not
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enough memory available, it uses various parameters to decide the process to
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kill. It is however possible to disable or curb this overcommit behavior
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by setting the proc sysctl vm.overcommit_memory to the value '2' and with
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that, a process is only allowed to use the maximum of a pre-determined
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fraction of the total address space. In such a case, we want to make sure
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that we are judicious with our heap usage as well, and explicitly give away
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the freed top of the heap to reduce our commit charge. See the proc(5) man
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page to know more about overcommit behavior.
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Other than that, we also force an unmap in a secure exec. */
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static inline bool
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check_may_shrink_heap (void)
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{
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static int may_shrink_heap = -1;
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if (__builtin_expect (may_shrink_heap >= 0, 1))
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return may_shrink_heap;
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may_shrink_heap = __libc_enable_secure;
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if (__builtin_expect (may_shrink_heap == 0, 1))
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{
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int fd = __open_nocancel ("/proc/sys/vm/overcommit_memory",
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O_RDONLY | O_CLOEXEC);
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if (fd >= 0)
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{
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char val;
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ssize_t n = __read_nocancel (fd, &val, 1);
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may_shrink_heap = n > 0 && val == '2';
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__close_nocancel_nostatus (fd);
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}
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}
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return may_shrink_heap;
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}
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#define HAVE_MREMAP 1
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