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2021-02-25Reduce the statically linked startup code [BZ #23323]Florian Weimer
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.
2021-01-02Update copyright dates with scripts/update-copyrightsPaul Eggert
I used these shell commands: ../glibc/scripts/update-copyrights $PWD/../gnulib/build-aux/update-copyright (cd ../glibc && git commit -am"[this commit message]") and then ignored the output, which consisted lines saying "FOO: warning: copyright statement not found" for each of 6694 files FOO. I then removed trailing white space from benchtests/bench-pthread-locks.c and iconvdata/tst-iconv-big5-hkscs-to-2ucs4.c, to work around this diagnostic from Savannah: remote: *** pre-commit check failed ... remote: *** error: lines with trailing whitespace found remote: error: hook declined to update refs/heads/master
2020-01-01Update copyright dates with scripts/update-copyrights.Joseph Myers
2019-09-07Prefer https to http for gnu.org and fsf.org URLsPaul Eggert
Also, change sources.redhat.com to sourceware.org. This patch was automatically generated by running the following shell script, which uses GNU sed, and which avoids modifying files imported from upstream: sed -ri ' s,(http|ftp)(://(.*\.)?(gnu|fsf|sourceware)\.org($|[^.]|\.[^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.
2018-09-12i386: Use ENTRY and END in start.S [BZ #23606]H.J. Lu
Wrapping the _start function with ENTRY and END to insert ENDBR32 at function entry when CET is enabled. Since _start now includes CFI, without "cfi_undefined (eip)", unwinder may not terminate at _start and we will get Program received signal SIGSEGV, Segmentation fault. 0xf7dc661e in ?? () from /lib/libgcc_s.so.1 Missing separate debuginfos, use: dnf debuginfo-install libgcc-8.2.1-3.0.fc28.i686 (gdb) bt #0 0xf7dc661e in ?? () from /lib/libgcc_s.so.1 #1 0xf7dc7c18 in _Unwind_Backtrace () from /lib/libgcc_s.so.1 #2 0xf7f0d809 in __GI___backtrace (array=array@entry=0xffffc7d0, size=size@entry=20) at ../sysdeps/i386/backtrace.c:127 #3 0x08049254 in compare (p1=p1@entry=0xffffcad0, p2=p2@entry=0xffffcad4) at backtrace-tst.c:12 #4 0xf7e2a28c in msort_with_tmp (p=p@entry=0xffffca5c, b=b@entry=0xffffcad0, n=n@entry=2) at msort.c:65 #5 0xf7e29f64 in msort_with_tmp (n=2, b=0xffffcad0, p=0xffffca5c) at msort.c:53 #6 msort_with_tmp (p=p@entry=0xffffca5c, b=b@entry=0xffffcad0, n=n@entry=5) at msort.c:53 #7 0xf7e29f64 in msort_with_tmp (n=5, b=0xffffcad0, p=0xffffca5c) at msort.c:53 #8 msort_with_tmp (p=p@entry=0xffffca5c, b=b@entry=0xffffcad0, n=n@entry=10) at msort.c:53 #9 0xf7e29f64 in msort_with_tmp (n=10, b=0xffffcad0, p=0xffffca5c) at msort.c:53 #10 msort_with_tmp (p=p@entry=0xffffca5c, b=b@entry=0xffffcad0, n=n@entry=20) at msort.c:53 #11 0xf7e2a5b6 in msort_with_tmp (n=20, b=0xffffcad0, p=0xffffca5c) at msort.c:297 #12 __GI___qsort_r (b=b@entry=0xffffcad0, n=n@entry=20, s=s@entry=4, cmp=cmp@entry=0x8049230 <compare>, arg=arg@entry=0x0) at msort.c:297 #13 0xf7e2a84d in __GI_qsort (b=b@entry=0xffffcad0, n=n@entry=20, s=s@entry=4, cmp=cmp@entry=0x8049230 <compare>) at msort.c:308 #14 0x080490f6 in main (argc=2, argv=0xffffcbd4) at backtrace-tst.c:39 FAIL: debug/backtrace-tst [BZ #23606] * sysdeps/i386/start.S: Include <sysdep.h> (_start): Use ENTRY/END to insert ENDBR32 at entry when CET is enabled. Add cfi_undefined (eip). Signed-off-by: H.J. Lu <hjl.tools@gmail.com>
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.
2017-10-03i386: Use "movl main@GOT(%ebx), %eax" in start.SH.J. Lu
Don't use "leal main@GOTOFF(%ebx), %eax" since main may be in a shared object. Linker will convert "movl main@GOT(%ebx), %eax" to "leal main@GOTOFF(%ebx), %eax" if main is defined locally. * sysdeps/i386/start.S: Replace "leal main@GOT(%ebx), %eax" with "movl main@GOTOFF(%ebx), %eax".
2017-08-04i386: Support static PIE in start.SH.J. Lu
Since start.o may be compiled as PIC, we should check PIC instead of SHARED. Also avoid dynamic relocation against main in static PIE since _start is the entry point before the executable is relocated. * sysdeps/i386/start.S (_start): Check Check PIC instead of SHARED. Avoid dynamic relocation against main in static PIE.
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
2013-02-21Remove remaining bounded-pointers support from i386 .S files.Joseph Myers
2013-01-02Update copyright notices with scripts/update-copyrights.Joseph Myers
2012-03-27Merge branch 'elf-move'Andreas Jaeger
Conflicts: debug/backtracesymsfd.c sysdeps/generic/elf/backtracesymsfd.c sysdeps/i386/configure.in
2012-03-19Merge sysdeps/i386/elf/Versions into sysdeps/i386/Versions.Andreas Jaeger
Move sysdeps/i386/elf/start.S to sysdeps/i386/ Merge sysdeps/i386/elf/configure.in into sysdeps/i386/configure.in Delete merged files sysdeps/i386/elf/configure.in, sysdeps/i386/elf/Versions and sysdeps/i386/elf/configure.