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2021-01-02Update copyright dates with scripts/update-copyrightsPaul Eggert
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
2020-02-14i386: Enable CET support in ucontext functionsH.J. Lu
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>
2020-02-01i386: Don't unnecessarily save and restore EAX, ECX and EDX [BZ# 25262]H.J. Lu
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>
2020-01-01Update copyright dates with scripts/update-copyrights.Joseph Myers
2019-09-07Prefer https to http for gnu.org and fsf.org URLsPaul Eggert
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
2019-01-01Update copyright dates with scripts/update-copyrights.Joseph Myers
* All files with FSF copyright notices: Update copyright dates using scripts/update-copyrights. * locale/programs/charmap-kw.h: Regenerated. * locale/programs/locfile-kw.h: Likewise.
2018-01-01Update copyright dates with scripts/update-copyrights.Joseph Myers
* All files with FSF copyright notices: Update copyright dates using scripts/update-copyrights. * locale/programs/charmap-kw.h: Regenerated. * locale/programs/locfile-kw.h: Likewise.
2017-01-01Update copyright dates with scripts/update-copyrights.Joseph Myers
2016-01-04Update copyright dates with scripts/update-copyrights.Joseph Myers
2015-01-02Update copyright dates with scripts/update-copyrights.Joseph Myers
2014-01-01Update copyright notices with scripts/update-copyrightsAllan McRae
2013-01-02Update copyright notices with scripts/update-copyrights.Joseph Myers
2012-07-25Remove unused pseudo_end labelAndreas Schwab
2012-02-09Replace FSF snail mail address with URLs.Paul Eggert
2005-05-26Add space inf weak_alias use.Ulrich Drepper
2004-12-22(CFLAGS-tst-align.c): Add -mpreferred-stack-boundary=4.Ulrich Drepper
2007-07-122.5-18.1Jakub Jelinek
2003-04-062003-04-06 Roland McGrath <roland@redhat.com>Roland McGrath
* sysdeps/unix/sysv/linux/i386/swapcontext.S: Rewrite register restoration as done for setcontext yesterday.
2002-12-20Update.Ulrich Drepper
* sysdeps/unix/sysv/linux/i386/pthread_once.S: Use ENTER_KERNEL instead of int $0x80. * sysdeps/unix/sysv/linux/i386/i486/libc-lowlevellock.S: Likewise. * sysdeps/unix/sysv/linux/i386/i486/libc-lowlevelmutex.S: Likewise. * sysdeps/unix/sysv/linux/i386/i486/lowlevelcond.S: Likewise. * sysdeps/unix/sysv/linux/i386/i486/lowlevellock.S: Likewise. * sysdeps/unix/sysv/linux/i386/i486/lowlevelmutex.S: Likewise. * sysdeps/unix/sysv/linux/i386/i486/lowlevelrwlock.S: Likewise. * sysdeps/unix/sysv/linux/i386/i486/lowlevelsem.S: Likewise. * sysdeps/unix/sysv/linux/i386/i486/pthread_barrier_wait.S: Likewise. * sysdeps/unix/sysv/linux/i386/lowlevellock.h: Add support for using sysenter. * sysdeps/unix/sysv/linux/i386/lowlevelsem.h: Likewise. * sysdeps/i386/tls.h: Unconditionally include <dl-sysdep.h>.
2001-07-31Update.Ulrich Drepper
* sysdeps/unix/sysv/linux/i386/getcontext.S: Don't touch the %gs register so that contexts can be used in different threads. * sysdeps/unix/sysv/linux/i386/setcontext.S: Likewise. * sysdeps/unix/sysv/linux/i386/swapcontext.S: Likewise.
2001-07-06Update to LGPL v2.1.Andreas Jaeger
2001-07-06 Paul Eggert <eggert@twinsun.com> * manual/argp.texi: Remove ignored LGPL copyright notice; it's not appropriate for documentation anyway. * manual/libc-texinfo.sh: "Library General Public License" -> "Lesser General Public License". 2001-07-06 Andreas Jaeger <aj@suse.de> * All files under GPL/LGPL version 2: Place under LGPL version 2.1.
2001-04-07Update.Ulrich Drepper
2001-04-07 Ulrich Drepper <drepper@redhat.com> * sysdeps/unix/sysv/linux/i386/getcontext.S: New file. * sysdeps/unix/sysv/linux/i386/setcontext.S: New file. * sysdeps/unix/sysv/linux/i386/makecontext.S: New file. * sysdeps/unix/sysv/linux/i386/swapcontext.S: New file. * sysdeps/unix/sysv/linux/i386/ucontext_i.h: New file. * sysdeps/unix/sysv/linux/i386/Dist: Add ucontext_i.h.