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Adhemerval Zanella ccf970c7a7 posix: Add compat glob symbol to not follow dangling symbols
This patch follows commit 5554304f0 (posix: Allow glob to match dangling
symlinks [BZ #866]) by adding a compat symbol that follow previous
semantic of not following dangling symlinks and thus avoiding call
gl_lstat with GLOB_ALTDIRFUNC.

It avoids failure with old binaries that not set the alternate function
pointer for lstat (GNUmake for instance).  The following scenario, for
instance, fails with current GNUmake because glibc will access unitialized
memory when calling gl_lstat:

  $ cat src/t/t.c
  int main ()
  {
    return 0;
  }
  $ cat Makefile
  SRC = $(wildcard src/*/t.c)
  OBJ = $(patsubst src/%.c, obj/%.o, $(SRC))

  prog:           $(OBJ)
                  $(CC) $(CFLAGS) $(LDFLAGS) $(LIBS) $(OBJ) -o prog

  obj/%.o:        src/%.c
                  $(CC) $(CFLAGS) -c $< -o $@
  $ make

This works as expected with the patch applied.  Since it is for generic
ABI, default compat symbols are added with override for Linux due LFS.
Now we have two compat symbols for glob on Linux:

  1. sysdeps/unix/sysv/linux/oldglob.c which implements glob64 with
     the old dirent layout.  For this implementation I also set it to
     not follow dangling symlinks (which is the safest path).

  2. sysdeps/unix/sysv/linux/glob{64}-lstat-compat.c which implements
     the compat symbol for dangling symlinks.  As for generic glob,
     the implementation uses XSTAT_IS_XSTAT64 to define whether
     both __glob_lstat_compat and __glob64_lstat_compat should be
     different implementations.  For archictures that define
     XSTAT_IS_XSTAT64, __glob_lstat_compat is aliased to
     __glob64_lstat_compat.

  3. sysdeps/unix/sysv/linux/alpha/oldglob.c with a different glob_t
     layout.  As for 1. this patch changes it to not follow dangling
     symlinks.

The patch also bumps _GNU_GLOB_INTERFACE_VERSION to 2 to advertise the
new semantic.  On GNUmake, for instance, it will force to it use its
internal glob implementation instead and avoiding triggering the same
failure on builds against newer GLIBCs.

Checked on x86_64-linux-gnu and i686-linux-gnu.  I also checked
with a build against the major ABIs required to check for the abilist.

The changes should also work on gnulib (I run gnulib-tool.py check glob
and it shown no regressions).

	[BZ #22183]
	* include/gnu-versions.h (_GNU_GLOB_INTERFACE_VERSION): Increase
	version to 2.
	* posix/Makefile (routines): Add glob-lstat-compat and
	glob64-lstat-compat.
	* posix/Versions (GLIBC_2.27, glob, glob64): Add symbol version.
	* posix/glob-lstat-compat.c: New file.
	* posix/glob64-lstat-compat.c: Likewise.
	* posix/tst-glob_lstat_compat.c: Likewise.
	* sysdeps/unix/sysv/linux/glob-lstat-compat.c: Likewise.
	* sysdeps/unix/sysv/linux/alpha/glob-lstat-compat.c: Likewise.
	* sysdeps/unix/sysv/linux/glob64-lstat-compat.c: Likewise.
	* sysdeps/unix/sysv/linux/alpha/glob.c: Remove file.
	* posix/glob.c (glob_lstat): New function.
	(glob): Rename to __glob and add versioned symbol to 2.27.
	(glob_in_dir): Use glob_lstat.
	* posix/glob64.c (glob64): Add GLOB_ATTRIBUTE.
	* sysdeps/unix/sysv/linux/arm/libc.abilist: Likewise.
	* sysdeps/unix/sysv/linux/glob.c (glob): Add versioned symbol for
	2.27.
	* sysdeps/unix/sysv/linux/glob64.c (glob64): Likewise.
	* sysdeps/unix/sysv/linux/oldglob.c (GLOB_NO_LSTAT): Define.
	* sysdeps/unix/sysv/linux/alpha/oldglob.c (__old_glob): Do not use
	gl_lstat on glob call.
	* sysdeps/unix/sysv/linux/aarch64/libc.abilist: Add GLIBC_2.27 glob
	and glob64 symbols.
	* sysdeps/unix/sysv/linux/alpha/libc.abilist: Likewise.
	* sysdeps/unix/sysv/linux/hppa/libc.abilist: Likewise.
	* sysdeps/unix/sysv/linux/i386/libc.abilist: Likewise.
	* sysdeps/unix/sysv/linux/ia64/libc.abilist: Likewise.
	* sysdeps/unix/sysv/linux/m68k/coldfire/libc.abilist: Likewise.
	* sysdeps/unix/sysv/linux/m68k/m680x0/libc.abilist: Likewise.
	* sysdeps/unix/sysv/linux/microblaze/libc.abilist: Likewise.
	* sysdeps/unix/sysv/linux/mips/mips32/fpu/libc.abilist: Likewise.
	* sysdeps/unix/sysv/linux/mips/mips32/nofpu/libc.abilist: Likewise.
	* sysdeps/unix/sysv/linux/mips/mips64/n32/libc.abilist: Likewise.
	* sysdeps/unix/sysv/linux/mips/mips64/n64/libc.abilist: Likewise.
	* sysdeps/unix/sysv/linux/nios2/libc.abilist: Likewise.
	* sysdeps/unix/sysv/linux/powerpc/powerpc32/fpu/libc.abilist:
	Likewise.
	* sysdeps/unix/linux/powerpc/powerpc32/nofpu/libc.abilist: Likewise.
	* sysdeps/unix/sysv/linux/powerpc/powerpc64/libc.abilist: Likewise.
	* sysdeps/unix/sysv/linux/s390/s390-32/libc.abilist: Likewise.
	* sysdeps/unix/sysv/linux/s390/s390-64/libc.abilist: Likewise.
	* sysdeps/unix/sysv/linux/sh/libc.abilist: Likewise.
	* sysdeps/unix/sysv/linux/sparc/sparc32/libc.abilist: Likewise.
	* sysdeps/unix/sysv/linux/sparc/sparc64/libc.abilist: Likewise.
	* sysdeps/unix/sysv/linux/tile/tilegx/tilegx32/libc.abilist: Likewise.
	* sysdeps/unix/sysv/linux/tile/tilegx/tilegx64/libc.abilist: Likewise.
	* sysdeps/unix/sysv/linux/tile/tilepro/libc.abilist: Likewise.
	* sysdeps/unix/sysv/linux/x86_64/64/libc.abilist: Likewise.
	* sysdeps/unix/sysv/linux/x86_64/x32/libc.abilist: Likewise.
2017-09-25 18:04:16 -07:00
ChangeLog.old Move all old ChangeLogs to a top-level ChangeLog.old directory. 2017-09-01 09:31:43 -04:00
argp Remove __need macros from errno.h (__need_Emath, __need_error_t). 2017-06-14 08:14:34 -04:00
assert Fix position of tests-unsupported definition in assert/Makefile. 2017-08-22 00:30:51 +00:00
benchtests Add exp2f and log2f benchmark trace 2017-09-20 10:04:12 +01:00
bits hurd: Fix bits/socket.h conformity 2017-09-24 22:21:41 +02:00
catgets Don't compile non-lib modules as lib modules [BZ #21864] 2017-08-21 05:34:54 -07:00
conform Fix mcontext_t sigcontext namespace (bug 21457). 2017-08-30 22:02:04 +00:00
crypt Remove non-add-on Banner files. 2017-09-21 17:49:51 +00:00
csu Remove Banner mechanism. 2017-09-22 17:43:42 +00:00
ctype Use locale_t, not __locale_t, throughout glibc 2017-06-20 20:30:06 -04:00
debug Enable unwind info in libc-start.c and backtrace.c 2017-09-19 15:07:58 +01:00
dev Rename xlocale.h to bits/types/__locale_t.h. 2017-06-20 20:28:11 -04:00
dirent dirent: Remove internal_function attribute 2017-08-31 16:02:40 +02:00
dlfcn dlfcn: Remove internal_function attribute 2017-08-31 16:12:03 +02:00
elf Fix $(error) use in Makefile 2017-09-10 17:39:39 +02:00
gmon gmon: Remove internal_function attribute 2017-08-31 16:16:07 +02:00
gnulib Update copyright dates with scripts/update-copyrights. 2017-01-01 00:14:16 +00:00
grp Remove compat from DEFAULT_CONFIG lookup strings 2017-09-12 10:21:48 -07:00
gshadow Remove __need macros from stdio.h and wchar.h. 2017-06-08 13:58:17 -04:00
hesiod Update copyright dates with scripts/update-copyrights. 2017-01-01 00:14:16 +00:00
hurd hurd: fix gethostname(NULL, 0) 2017-09-07 00:51:17 +02:00
iconv iconv, intl, locale, wcsmbs: Remove internal_function 2017-08-31 15:59:06 +02:00
iconvdata Add new codepage charmaps/IBM858 [BZ #21084] 2017-09-14 15:50:57 +02:00
include posix: Add compat glob symbol to not follow dangling symbols 2017-09-25 18:04:16 -07:00
inet inet: Remove internal_function attribute 2017-08-31 18:52:00 +02:00
intl iconv, intl, locale, wcsmbs: Remove internal_function 2017-08-31 15:59:06 +02:00
io Add missing libc_hidden_weak/def calls 2017-09-17 21:57:39 +02:00
libidn Remove Banner mechanism. 2017-09-22 17:43:42 +00:00
libio Finish change from “Bengali” to “Bangla” 2017-09-09 12:41:54 +02:00
locale Finish change from “Bengali” to “Bangla” 2017-09-09 12:41:54 +02:00
localedata Add new codepage charmaps/IBM858 [BZ #21084] 2017-09-14 15:50:57 +02:00
login Consolidate remaning non cancellable definitions 2017-08-23 10:47:03 -03:00
mach hurd: Remove duplicate symbol version 2017-08-28 14:19:55 +02:00
malloc Sync scratch_buffer with gnulib 2017-09-08 15:51:34 +02:00
manual Remove Banner mechanism. 2017-09-22 17:43:42 +00:00
math New expf and exp2f version without SVID compat wrapper 2017-09-25 10:45:08 +01:00
mathvec Update copyright dates with scripts/update-copyrights. 2017-01-01 00:14:16 +00:00
misc hurd: Fix build ot misc/tst-preadvwritev2-common.c 2017-09-03 17:51:15 +02:00
nis Consistently use uintN_t not u_intN_t everywhere. 2017-08-07 19:55:34 +00:00
nptl Remove non-add-on Banner files. 2017-09-21 17:49:51 +00:00
nptl_db Move all old ChangeLogs to a top-level ChangeLog.old directory. 2017-09-01 09:31:43 -04:00
nscd nscd: Release read lock after resetting timeout. 2017-09-25 19:49:36 -04:00
nss Remove compat from DEFAULT_CONFIG lookup strings 2017-09-12 10:21:48 -07:00
po Update translations 2017-09-11 05:50:49 +05:30
posix posix: Add compat glob symbol to not follow dangling symbols 2017-09-25 18:04:16 -07:00
pwd Remove __need macros from stdio.h and wchar.h. 2017-06-08 13:58:17 -04:00
resolv Remove non-add-on Banner files. 2017-09-21 17:49:51 +00:00
resource Define struct rusage in sys/wait.h when required (bug 21575). 2017-06-19 11:59:19 +00:00
rt aio: Remove internal_function function attribute 2017-08-31 15:59:06 +02:00
scripts Use MPFR 3.1.6 in build-many-glibcs.py. 2017-09-07 14:50:32 +00:00
setjmp Remove __need macros from signal.h. 2017-05-20 19:04:43 -04:00
shadow Remove __need macros from stdio.h and wchar.h. 2017-06-08 13:58:17 -04:00
signal Fix sigval namespace (bug 21944). 2017-08-16 20:33:59 +00:00
socket __opensock: Remove internal_function attribute 2017-08-17 10:18:15 +02:00
soft-fp Remove non-add-on Banner files. 2017-09-21 17:49:51 +00:00
stdio-common linux: Implement tmpfile with O_TMPFILE (BZ#21530) 2017-09-01 09:52:47 -03:00
stdlib Reduce total memory required to create all threads to 128MiB. This fixes 2017-09-25 17:51:34 -07:00
streams Update copyright dates with scripts/update-copyrights. 2017-01-01 00:14:16 +00:00
string string/stratcliff.c: Replace int with size_t [BZ #21982] 2017-08-23 08:23:02 -07:00
sunrpc sunrpc/tst-udp-nonblocking: Fix timeout value 2017-09-10 21:09:28 +02:00
support Revert "resolv_test.c: also cope with CONNREFUSED errors returned by recvfrom" 2017-09-25 20:47:51 +02:00
sysdeps posix: Add compat glob symbol to not follow dangling symbols 2017-09-25 18:04:16 -07:00
sysvipc Fix test-sysvsem on some platforms 2017-01-02 18:53:50 -02:00
termios Update copyright dates with scripts/update-copyrights. 2017-01-01 00:14:16 +00:00
time time: Remove the internal_function attribute 2017-08-31 15:59:07 +02:00
timezone zic: Use PRIdMAX to print line numbers 2017-07-25 12:34:14 +05:30
wcsmbs iconv, intl, locale, wcsmbs: Remove internal_function 2017-08-31 15:59:06 +02:00
wctype Use locale_t, not __locale_t, throughout glibc 2017-06-20 20:30:06 -04:00
.gitattributes Assume __NR_openat is always defined 2016-03-23 23:35:08 +01:00
.gitignore Add *.pyc to .gitignore 2015-05-18 15:26:26 +05:30
COPYING Update to latest versions of GPL-2.0 and LGPL-2.1 2013-09-09 12:52:48 +10:00
COPYING.LIB Update to latest versions of GPL-2.0 and LGPL-2.1 2013-09-09 12:52:48 +10:00
ChangeLog posix: Add compat glob symbol to not follow dangling symbols 2017-09-25 18:04:16 -07:00
INSTALL Update contributors and latest gcc and binutils versions 2017-08-02 18:22:58 +05:30
LICENSES Expand LICENSES file. 2012-12-05 21:56:15 +00:00
MAINTAINERS Add MAINTAINERS 2017-05-11 13:38:30 -04:00
Makeconfig Support mcount/gprof test with GCC defaulting to PIE 2017-08-17 04:56:01 -07:00
Makefile Suppress internal declarations for most of the testsuite. 2017-05-11 19:27:59 -04:00
Makefile.in New make target to only build benchmark binaries 2016-04-20 10:23:28 +05:30
Makerules Place $(elf-objpfx)sofini.os last [BZ #22051] 2017-08-31 06:28:46 -07:00
NEWS Optimized generic expf and exp2f with wrappers 2017-09-25 10:44:39 +01:00
README Require Linux kernel 3.2 or later on x86 / x86_64. 2017-05-08 10:45:20 +00:00
Rules Suppress internal declarations for most of the testsuite. 2017-05-11 19:27:59 -04:00
abi-tags Remove the bulk of the NaCl port. 2017-05-20 08:09:10 -04:00
aclocal.m4 gmon: Add test for basic mcount/gprof functionality 2017-08-15 15:49:45 +02:00
config.h.in i386: Do not set internal_function 2017-08-14 15:08:48 +02:00
config.make.in gmon: Add test for basic mcount/gprof functionality 2017-08-15 15:49:45 +02:00
configure Update configure.ac for binutils 2.25 2017-09-25 18:01:34 -07:00
configure.ac Update configure.ac for binutils 2.25 2017-09-25 18:01:34 -07:00
extra-lib.mk Rename cppflags-iterator.mk to libof-iterator.mk, remove extra-modules.mk. 2017-05-09 07:06:29 -04:00
gen-locales.mk Split locale generation snippet into a separate file 2015-05-13 13:05:28 +05:30
libc-abis A few more archs have IFUNC support. 2010-03-17 02:43:12 -07:00
libof-iterator.mk Rename cppflags-iterator.mk to libof-iterator.mk, remove extra-modules.mk. 2017-05-09 07:06:29 -04:00
o-iterator.mk Fri Mar 17 12:58:37 1995 Roland McGrath <roland@churchy.gnu.ai.mit.edu> 1995-03-17 18:42:51 +00:00
shlib-versions Extend NSS test suite 2017-07-17 15:52:44 -04:00
test-skeleton.c Update copyright dates with scripts/update-copyrights. 2017-01-01 00:14:16 +00:00
version.h Open master for development 2017-08-02 19:23:16 +05:30

README

This directory contains the sources of the GNU C Library.
See the file "version.h" for what release version you have.

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