Go to file
Pavel Kopyl 02d5e5d94a Add forced deletion support to _dl_close_worker
https://sourceware.org/bugzilla/show_bug.cgi?id=17833

I've a shared library that contains both undefined and unique symbols.
Then I try to call the following sequence of dlopen:

1. dlopen("./libfoo.so", RTLD_NOW)
2. dlopen("./libfoo.so", RTLD_LAZY | RTLD_GLOBAL)

First dlopen call terminates with error because of undefined symbols,
but STB_GNU_UNIQUE ones set DF_1_NODELETE flag and hence block library
in the memory.

The library goes into inconsistent state as several structures remain
uninitialized. For instance, relocations for GOT table were not performed.

By the time of second dlopen call this library looks like as it would be
fully initialized but this is not true: any call through incorrect GOT
table leads to segmentation fault.  On some systems this inconsistency
triggers assertions in the dynamic linker.

This patch adds a parameter to _dl_close_worker to implement forced object
deletion in case of dlopen() failure:

1. Clears DF_1_NODELETE bit if forced, to allow library to be removed from
memory.
2. For each unique symbol that is defined in this object clears
appropriate entry in _ns_unique_sym_table.

	[BZ #17833]
	* elf/Makefile (tests): Add tst-nodelete.
	(modules-names): Add tst-nodelete-uniquemod.
	(tst-nodelete-uniquemod.so-no-z-defs): New.
	(tst-nodelete-rtldmod.so-no-z-defs): Likewise.
	(tst-nodelete-zmod.so-no-z-defs): Likewise.
	($(objpfx)tst-nodelete): Likewise.
	($(objpfx)tst-nodelete.out): Likewise.
	(LDFLAGS-tst-nodelete): Likewise.
	(LDFLAGS-tst-nodelete-zmod.so): Likewise.
	* elf/dl-close.c (_dl_close_worker): Add a parameter to
	implement forced object deletion.
	(_dl_close): Pass false to _dl_close_worker.
	* elf/dl-open.c (_dl_open): Pass true to _dl_close_worker.
	* elf/tst-nodelete.cc: New file.
	* elf/tst-nodeletelib.cc: Likewise.
	* elf/tst-znodeletelib.cc: Likewise.
	* include/dlfcn.h (_dl_close_worker): Add a new parameter.
2015-07-07 11:06:56 -07:00
argp Update copyright dates with scripts/update-copyrights. 2015-01-02 16:29:47 +00:00
assert Add ersatz _Static_assert on older C hosts 2015-02-07 14:43:27 -08:00
benchtests Fix benchtests build failure after 'add benchmark for strcoll' 2015-06-19 13:47:59 +02:00
bits Vector sincos for x86_64 and tests. 2015-06-18 17:55:55 +03:00
catgets Update copyright dates not handled by scripts/update-copyrights. 2015-01-02 16:54:45 +00:00
conf (NEED_INETADDR, NEED_INETATON): Define to 1, not empty. 1995-09-08 20:24:57 +00:00
conform conformtest: Fix pselect expectations. 2015-06-19 20:52:44 +00:00
crypt Update copyright dates with scripts/update-copyrights. 2015-01-02 16:29:47 +00:00
csu Align TCB offset to the maximum alignment 2015-06-24 16:30:58 -07:00
ctype Fix isblank / isascii / toascii namespace (bug 17635). 2015-01-05 15:06:57 +00:00
debug Let tests result in UNSUPPORTED; use that for unbuildable C++ cases 2015-03-10 15:13:14 -07:00
dirent Nit fixes in last change. 2015-05-13 12:39:01 -07:00
dlfcn Convert dlfcn/tststatic to use test-skeleton. 2015-03-27 12:55:25 -07:00
elf Add forced deletion support to _dl_close_worker 2015-07-07 11:06:56 -07:00
gmon Update copyright dates with scripts/update-copyrights. 2015-01-02 16:29:47 +00:00
gnulib Update copyright dates with scripts/update-copyrights. 2015-01-02 16:29:47 +00:00
grp Fix grp.h endgrent, getgrent namespace (bug 18528). 2015-06-12 22:29:19 +00:00
gshadow Update copyright dates with scripts/update-copyrights. 2015-01-02 16:29:47 +00:00
hesiod Update copyright dates with scripts/update-copyrights. 2015-01-02 16:29:47 +00:00
hurd Fix warnings 2015-03-21 04:49:44 +01:00
iconv Convert tst-iconv3 to use test-skeleton. 2015-02-25 16:01:13 -08:00
iconvdata Update copyright dates with scripts/update-copyrights. 2015-01-02 16:29:47 +00:00
include Add forced deletion support to _dl_close_worker 2015-07-07 11:06:56 -07:00
inet Fix gethostbyaddr in6addr_any, in6addr_loopback namespace (bug 18532). 2015-06-17 20:08:22 +00:00
intl Remove obsolete aliases that broke 'locale -a' 2015-05-22 15:12:01 -07:00
io posix_fallocate, posix_fallocate64 stub: Do not set errno 2015-04-24 20:08:43 +02:00
libidn Update copyright dates with scripts/update-copyrights. 2015-01-02 16:29:47 +00:00
libio Fix buffer overflow for writes to memory buffer stream (bug 18549) 2015-06-25 15:54:09 +02:00
locale Remove unused PREDEFINED_CLASSES code 2015-06-09 09:34:06 +02:00
localedata Fix sorting order for Ukrainian locale (BZ 17293) 2015-05-26 23:51:18 +05:30
login Fix getlogin_r namespace (bug 18527). 2015-06-12 20:02:30 +00:00
mach mach: fix typo 2015-06-06 11:48:42 +02:00
malloc malloc: Do not corrupt the top of a threaded heap if top chunk is MINSIZE [BZ #18502] 2015-06-26 22:47:45 +02:00
manual Attempting to install glibc configured with --prefix=/usr into 2015-06-12 13:15:57 -06:00
math Improve tgamma accuracy (bug 18613). 2015-06-29 23:29:35 +00:00
mathvec This is update for configure, build and install of vector math library. 2015-05-14 18:07:06 +03:00
misc Set errno to ENOMEM on overflow in sbrk (bug 18592) 2015-07-07 12:13:50 +02:00
nis Separate internal state between getXXent and getXXbyYY NSS calls (bug 18007) 2015-05-11 10:41:49 +02:00
nptl The C++ 2011 std::call_once function is specified to allow 2015-07-01 14:05:27 -06:00
nptl_db Fix DTV race, assert, DTV_SURPLUS Static TLS limit, and nptl_db garbage 2015-03-17 00:31:49 -03:00
nscd Clean up BUSY_WAIT_NOP and atomic_delay. 2015-06-30 15:57:15 +02:00
nss Separate internal state between getXXent and getXXbyYY NSS calls (bug 18007) 2015-05-11 10:41:49 +02:00
po glibc 2.21 pre-release update. 2015-02-05 23:14:38 -05:00
posix Fix getlogin_r namespace (bug 18527). 2015-06-12 20:02:30 +00:00
pwd tst-getpw: Rewrite. 2015-01-21 10:08:18 -05:00
resolv Use unsigned types for counters in getaddrinfo_a code. 2015-06-24 17:58:12 -07:00
resource Fix nice getpriority, setpriority namespace (bug 18553). 2015-06-17 20:22:39 +00:00
rt Fix mq_receive, mq_send mq_timed* namespace (bug 18545). 2015-06-17 20:19:04 +00:00
scripts Add more exception to local headers list 2015-03-23 00:31:02 +01:00
setjmp Update copyright dates with scripts/update-copyrights. 2015-01-02 16:29:47 +00:00
shadow Update copyright dates with scripts/update-copyrights. 2015-01-02 16:29:47 +00:00
signal Fix psignal, psiginfo declaration conditions (bug 18483). 2015-06-05 21:14:16 +00:00
socket Fix mq_notify socket, recv namespace (bug 18546). 2015-06-17 20:20:08 +00:00
soft-fp Fix soft-fp fma for -Wuninitialized. 2015-05-22 20:28:50 +00:00
stdio-common Fix syslog dprintf namespace (bug 18534). 2015-06-17 20:10:50 +00:00
stdlib S390: Fix "backtrace() returns infinitely deep stack frames with makecontext()" [BZ #18508]. 2015-07-07 16:11:14 +02:00
streams Update copyright dates with scripts/update-copyrights. 2015-01-02 16:29:47 +00:00
string remove unnecessary memset in strcoll 2015-06-22 07:53:09 +05:30
sunrpc Use calloc to allocate xports (BZ #17542) 2015-03-18 14:51:26 +05:30
sysdeps S390: Fix "backtrace() returns infinitely deep stack frames with makecontext()" [BZ #18508]. 2015-07-07 16:11:14 +02:00
sysvipc Update copyright dates with scripts/update-copyrights. 2015-01-02 16:29:47 +00:00
termios Update copyright dates with scripts/update-copyrights. 2015-01-02 16:29:47 +00:00
time Check tzspec_len == 0 in __tzfile_read 2015-04-27 09:57:51 -07:00
timezone Fix timezone tests run in parallel. 2015-06-19 13:47:59 +02:00
wcsmbs Fix regcomp wcscoll, wcscmp namespace (bug 18497). 2015-06-09 21:07:30 +00:00
wctype Fix regex wctype namespace (bug 18495). 2015-06-05 20:04:47 +00:00
.gitattributes exempt timezone files from the no-bad-whitespace policy 2009-06-15 18:15:54 +02:00
.gitignore Add *.pyc to .gitignore 2015-05-18 15:26:26 +05:30
abi-tags Add arm-nacl port. 2015-04-17 09:02:19 -07:00
aclocal.m4 Make aclocal.m4 comment mention updating install.texi for autoconf version. 2014-10-31 22:44:17 +00:00
BUGS [BZ #5222] 2007-10-28 08:24:07 +00:00
ChangeLog Add forced deletion support to _dl_close_worker 2015-07-07 11:06:56 -07:00
ChangeLog.1 * Makefile (distribute): Add ChangeLog.[0-9]. 1995-04-14 03:52:54 +00:00
ChangeLog.2 * Makefile (distribute): Add ChangeLog.[0-9]. 1995-04-14 03:52:54 +00:00
ChangeLog.3 * Makefile (distribute): Add ChangeLog.[0-9]. 1995-04-14 03:52:54 +00:00
ChangeLog.4 * Makefile (distribute): Add ChangeLog.[0-9]. 1995-04-14 03:52:54 +00:00
ChangeLog.5 * sysdeps/posix/getaddrinfo.c: Implement configuration file 2006-05-04 06:38:07 +00:00
ChangeLog.6 Update. 1997-07-22 00:10:33 +00:00
ChangeLog.7 Update. 1997-11-18 02:50:07 +00:00
ChangeLog.8 Update. Old logs are in ChangeLog.7. 1998-08-11 18:44:11 +00:00
ChangeLog.9 Update. 2000-04-28 06:14:43 +00:00
ChangeLog.10 Update. 2000-02-29 01:13:44 +00:00
ChangeLog.11 2.5-18.1 2007-07-12 18:26:36 +00:00
ChangeLog.12 2.5-18.1 2007-07-12 18:26:36 +00:00
ChangeLog.13 Update. 2002-10-03 16:37:04 +00:00
ChangeLog.14 Update. 2004-04-20 04:28:00 +00:00
ChangeLog.15 Split out ChangeLog.15 at 2.3 branch point 2005-02-16 07:34:17 +00:00
ChangeLog.16 Fix typo in name 2012-06-21 16:45:27 +02:00
ChangeLog.17 Revert "Sun agreed to a change of the license for the RPC code to a BSD-like license." 2010-06-27 19:34:03 -07:00
ChangeLog.old-ports Move ports/ChangeLog* files to ChangeLog.old-ports*, remove ports/ directory. 2014-04-30 10:40:29 -07:00
ChangeLog.old-ports-aarch64 Move ports/ChangeLog* files to ChangeLog.old-ports*, remove ports/ directory. 2014-04-30 10:40:29 -07:00
ChangeLog.old-ports-aix Move ports/ChangeLog* files to ChangeLog.old-ports*, remove ports/ directory. 2014-04-30 10:40:29 -07:00
ChangeLog.old-ports-alpha Move ports/ChangeLog* files to ChangeLog.old-ports*, remove ports/ directory. 2014-04-30 10:40:29 -07:00
ChangeLog.old-ports-am33 Move ports/ChangeLog* files to ChangeLog.old-ports*, remove ports/ directory. 2014-04-30 10:40:29 -07:00
ChangeLog.old-ports-arm Move ports/ChangeLog* files to ChangeLog.old-ports*, remove ports/ directory. 2014-04-30 10:40:29 -07:00
ChangeLog.old-ports-cris Move ports/ChangeLog* files to ChangeLog.old-ports*, remove ports/ directory. 2014-04-30 10:40:29 -07:00
ChangeLog.old-ports-hppa Move ports/ChangeLog* files to ChangeLog.old-ports*, remove ports/ directory. 2014-04-30 10:40:29 -07:00
ChangeLog.old-ports-ia64 Move ports/ChangeLog* files to ChangeLog.old-ports*, remove ports/ directory. 2014-04-30 10:40:29 -07:00
ChangeLog.old-ports-linux-generic Move ports/ChangeLog* files to ChangeLog.old-ports*, remove ports/ directory. 2014-04-30 10:40:29 -07:00
ChangeLog.old-ports-m68k Move ports/ChangeLog* files to ChangeLog.old-ports*, remove ports/ directory. 2014-04-30 10:40:29 -07:00
ChangeLog.old-ports-microblaze Move ports/ChangeLog* files to ChangeLog.old-ports*, remove ports/ directory. 2014-04-30 10:40:29 -07:00
ChangeLog.old-ports-mips Move ports/ChangeLog* files to ChangeLog.old-ports*, remove ports/ directory. 2014-04-30 10:40:29 -07:00
ChangeLog.old-ports-powerpc Move ports/ChangeLog* files to ChangeLog.old-ports*, remove ports/ directory. 2014-04-30 10:40:29 -07:00
ChangeLog.old-ports-tile Move ports/ChangeLog* files to ChangeLog.old-ports*, remove ports/ directory. 2014-04-30 10:40:29 -07:00
config.h.in [AArch64] Fix the big endian loader name. 2015-05-01 13:58:55 +01:00
config.make.in Support compilers defaulting to PIE 2015-06-25 02:49:53 -07:00
configure Support compilers defaulting to PIE 2015-06-25 02:49:53 -07:00
configure.ac Support compilers defaulting to PIE 2015-06-25 02:49:53 -07:00
CONFORMANCE Move __STDC_* predefined macros from features.h to stdc-predef.h. 2012-02-22 12:53:04 +00:00
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
cppflags-iterator.mk 2004-03-11 Jeroen Dekkers <jeroen@dekkers.cx> 2004-03-14 19:13:17 +00:00
extra-lib.mk Remove NOT_IN_libc 2014-11-24 15:03:45 +05:30
extra-modules.mk Remove NOT_IN_libc 2014-11-24 15:03:45 +05:30
gen-locales.mk Split locale generation snippet into a separate file 2015-05-13 13:05:28 +05:30
INSTALL Attempting to install glibc configured with --prefix=/usr into 2015-06-12 13:15:57 -06:00
libc-abis A few more archs have IFUNC support. 2010-03-17 02:43:12 -07:00
LICENSES Expand LICENSES file. 2012-12-05 21:56:15 +00:00
Makeconfig Support compilers defaulting to PIE 2015-06-25 02:49:53 -07:00
Makefile Succeed if make check does not report any errors 2015-05-19 06:36:29 +05:30
Makefile.in Remove redundant C locale settings. 2014-06-07 19:58:36 +00:00
Makerules Attempting to install glibc configured with --prefix=/usr into 2015-06-12 13:15:57 -06:00
NAMESPACE Add and update many more entries. 2000-03-20 00:42:58 +00:00
NEWS Add forced deletion support to _dl_close_worker 2015-07-07 11:06:56 -07:00
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
PROJECTS Update. 2004-10-12 06:19:23 +00:00
README Another pointless update in README. 2015-02-11 14:39:30 -08:00
Rules Let tests result in UNSUPPORTED; use that for unbuildable C++ cases 2015-03-10 15:13:14 -07:00
shlib-versions This is update for configure, build and install of vector math library. 2015-05-14 18:07:06 +03:00
test-skeleton.c Avoid outputting to TTY after an expected memory corruption in testcase 2015-06-05 09:39:49 -03:00
version.h Open development for 2.22. 2015-02-06 02:03:41 -05:00
WUR-REPORT * posix/unistd.h (setuid, setreuid, seteuid, setresuid): 2012-08-01 18:12:58 +02:00

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

The GNU C Library is the standard system C library for all GNU systems,
and is an important part of what makes up a GNU system.  It provides the
system API for all programs written in C and C-compatible languages such
as C++ and Objective C; the runtime facilities of other programming
languages use the C library to access the underlying operating system.

In GNU/Linux systems, the C library works with the Linux kernel to
implement the operating system behavior seen by user applications.
In GNU/Hurd systems, it works with a microkernel and Hurd servers.

The GNU C Library implements much of the POSIX.1 functionality in the
GNU/Hurd system, using configurations i[4567]86-*-gnu.  The current
GNU/Hurd support requires out-of-tree patches that will eventually be
incorporated into an official GNU C Library release.

When working with Linux kernels, this version of the GNU C Library
requires Linux kernel version 2.6.32 or later.

Also note that the shared version of the libgcc_s library must be
installed for the pthread library to work correctly.

The GNU C Library supports these configurations for using Linux kernels:

	aarch64*-*-linux-gnu
	alpha*-*-linux-gnu
	arm-*-linux-gnueabi
	hppa-*-linux-gnu	Not currently functional without patches.
	i[4567]86-*-linux-gnu
	x86_64-*-linux-gnu	Can build either x86_64 or x32
	ia64-*-linux-gnu
	m68k-*-linux-gnu
	microblaze*-*-linux-gnu
	mips-*-linux-gnu
	mips64-*-linux-gnu
	powerpc-*-linux-gnu	Hardware or software floating point, BE only.
	powerpc64*-*-linux-gnu	Big-endian and little-endian.
	s390-*-linux-gnu
	s390x-*-linux-gnu
	sh[34]-*-linux-gnu
	sparc*-*-linux-gnu
	sparc64*-*-linux-gnu
	tilegx-*-linux-gnu
	tilepro-*-linux-gnu

If you are interested in doing a port, please contact the glibc
maintainers; see http://www.gnu.org/software/libc/ for more
information.

See the file INSTALL to find out how to configure, build, and install
the GNU C Library.  You might also consider reading the WWW pages for
the C library at http://www.gnu.org/software/libc/.

The GNU C Library is (almost) completely documented by the Texinfo manual
found in the `manual/' subdirectory.  The manual is still being updated
and contains some known errors and omissions; we regret that we do not
have the resources to work on the manual as much as we would like.  For
corrections to the manual, please file a bug in the `manual' component,
following the bug-reporting instructions below.  Please be sure to check
the manual in the current development sources to see if your problem has
already been corrected.

Please see http://www.gnu.org/software/libc/bugs.html for bug reporting
information.  We are now using the Bugzilla system to track all bug reports.
This web page gives detailed information on how to report bugs properly.

The GNU C Library is free software.  See the file COPYING.LIB for copying
conditions, and LICENSES for notices about a few contributions that require
these additional notices to be distributed.  License copyright years may be
listed using range notation, e.g., 1996-2015, indicating that every year in
the range, inclusive, is a copyrightable year that would otherwise be listed
individually.