Commit Graph

97 Commits

Author SHA1 Message Date
Florian Weimer
dd32e1db38 Revert "elf: Always call destructors in reverse constructor order (bug 30785)"
This reverts commit 6985865bc3.

Reason for revert:

The commit changes the order of ELF destructor calls too much relative
to what applications expect or can handle.  In particular, during
process exit and _dl_fini, after the revert commit, we no longer call
the destructors of the main program first; that only happens after
some dlopen'ed objects have been destructed.  This robs applications
of an opportunity to influence destructor order by calling dlclose
explicitly from the main program's ELF destructors.  A couple of
different approaches involving reverse constructor order were tried,
and none of them worked really well.  It seems we need to keep the
dependency sorting in _dl_fini.

There is also an ambiguity regarding nested dlopen calls from ELF
constructors: Should those destructors run before or after the object
that called dlopen?  Commit 6985865bc3 used reverse order
of the start of ELF constructor calls for destructors, but arguably
using completion of constructors is more correct.  However, that alone
is not sufficient to address application compatibility issues (it
does not change _dl_fini ordering at all).
2023-10-18 11:30:38 +02:00
Florian Weimer
53df2ce688 elf: Remove unused l_text_end field from struct link_map
It is a left-over from commit 52a01100ad
("elf: Remove ad-hoc restrictions on dlopen callers [BZ #22787]").

When backporting commmit 6985865bc3
("elf: Always call destructors in reverse constructor order
(bug 30785)"), we can move the l_init_called_next field to this
place, so that the internal GLIBC_PRIVATE ABI does not change.

Reviewed-by: Carlos O'Donell <carlos@redhat.com>
Tested-by: Carlos O'Donell <carlos@redhat.com>
2023-09-08 18:39:20 +02:00
Florian Weimer
6985865bc3 elf: Always call destructors in reverse constructor order (bug 30785)
The current implementation of dlclose (and process exit) re-sorts the
link maps before calling ELF destructors.  Destructor order is not the
reverse of the constructor order as a result: The second sort takes
relocation dependencies into account, and other differences can result
from ambiguous inputs, such as cycles.  (The force_first handling in
_dl_sort_maps is not effective for dlclose.)  After the changes in
this commit, there is still a required difference due to
dlopen/dlclose ordering by the application, but the previous
discrepancies went beyond that.

A new global (namespace-spanning) list of link maps,
_dl_init_called_list, is updated right before ELF constructors are
called from _dl_init.

In dl_close_worker, the maps variable, an on-stack variable length
array, is eliminated.  (VLAs are problematic, and dlclose should not
call malloc because it cannot readily deal with malloc failure.)
Marking still-used objects uses the namespace list directly, with
next and next_idx replacing the done_index variable.

After marking, _dl_init_called_list is used to call the destructors
of now-unused maps in reverse destructor order.  These destructors
can call dlopen.  Previously, new objects do not have l_map_used set.
This had to change: There is no copy of the link map list anymore,
so processing would cover newly opened (and unmarked) mappings,
unloading them.  Now, _dl_init (indirectly) sets l_map_used, too.
(dlclose is handled by the existing reentrancy guard.)

After _dl_init_called_list traversal, two more loops follow.  The
processing order changes to the original link map order in the
namespace.  Previously, dependency order was used.  The difference
should not matter because relocation dependencies could already
reorder link maps in the old code.

The changes to _dl_fini remove the sorting step and replace it with
a traversal of _dl_init_called_list.  The l_direct_opencount
decrement outside the loader lock is removed because it appears
incorrect: the counter manipulation could race with other dynamic
loader operations.

tst-audit23 needs adjustments to the changes in LA_ACT_DELETE
notifications.  The new approach for checking la_activity should
make it clearer that la_activty calls come in pairs around namespace
updates.

The dependency sorting test cases need updates because the destructor
order is always the opposite order of constructor order, even with
relocation dependencies or cycles present.

There is a future cleanup opportunity to remove the now-constant
force_first and for_fini arguments from the _dl_sort_maps function.

Fixes commit 1df71d32fe ("elf: Implement
force_first handling in _dl_sort_maps_dfs (bug 28937)").

Reviewed-by: DJ Delorie <dj@redhat.com>
2023-09-08 12:34:27 +02:00
Joseph Myers
6d7e8eda9b Update copyright dates with scripts/update-copyrights 2023-01-06 21:14:39 +00:00
H.J. Lu
57292f5741 Add GLIBC_ABI_DT_RELR for DT_RELR support
The EI_ABIVERSION field of the ELF header in executables and shared
libraries can be bumped to indicate the minimum ABI requirement on the
dynamic linker.  However, EI_ABIVERSION in executables isn't checked by
the Linux kernel ELF loader nor the existing dynamic linker.  Executables
will crash mysteriously if the dynamic linker doesn't support the ABI
features required by the EI_ABIVERSION field.  The dynamic linker should
be changed to check EI_ABIVERSION in executables.

Add a glibc version, GLIBC_ABI_DT_RELR, to indicate DT_RELR support so
that the existing dynamic linkers will issue an error on executables with
GLIBC_ABI_DT_RELR dependency.  When there is a DT_VERNEED entry with
libc.so on DT_NEEDED, issue an error if there is a DT_RELR entry without
GLIBC_ABI_DT_RELR dependency.

Support __placeholder_only_for_empty_version_map as the placeholder symbol
used only for empty version map to generate GLIBC_ABI_DT_RELR without any
symbols.
2022-04-26 10:16:11 -07:00
Adhemerval Zanella
6628c742b2 elf: Remove prelink support
Prelinked binaries and libraries still work, the dynamic tags
DT_GNU_PRELINKED, DT_GNU_LIBLIST, DT_GNU_CONFLICT just ignored
(meaning the process is reallocated as default).

The loader environment variable TRACE_PRELINKING is also removed,
since it used solely on prelink.

Checked on x86_64-linux-gnu, i686-linux-gnu, and aarch64-linux-gnu.

Reviewed-by: Siddhesh Poyarekar <siddhesh@sourceware.org>
2022-02-10 09:16:12 -03:00
Paul Eggert
581c785bf3 Update copyright dates with scripts/update-copyrights
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 7061 files FOO.

I then removed trailing white space from math/tgmath.h,
support/tst-support-open-dev-null-range.c, and
sysdeps/x86_64/multiarch/strlen-vec.S, to work around the following
obscure pre-commit check failure diagnostics from Savannah.  I don't
know why I run into these diagnostics whereas others evidently do not.

remote: *** 912-#endif
remote: *** 913:
remote: *** 914-
remote: *** error: lines with trailing whitespace found
...
remote: *** error: sysdeps/unix/sysv/linux/statx_cp.c: trailing lines
2022-01-01 11:40:24 -08:00
Florian Weimer
5d28a8962d elf: Add _dl_find_object function
It can be used to speed up the libgcc unwinder, and the internal
_dl_find_dso_for_object function (which is used for caller
identification in dlopen and related functions, and in dladdr).

_dl_find_object is in the internal namespace due to bug 28503.
If libgcc switches to _dl_find_object, this namespace issue will
be fixed.  It is located in libc for two reasons: it is necessary
to forward the call to the static libc after static dlopen, and
there is a link ordering issue with -static-libgcc and libgcc_eh.a
because libc.so is not a linker script that includes ld.so in the
glibc build tree (so that GCC's internal -lc after libgcc_eh.a does
not pick up ld.so).

It is necessary to do the i386 customization in the
sysdeps/x86/bits/dl_find_object.h header shared with x86-64 because
otherwise, multilib installations are broken.

The implementation uses software transactional memory, as suggested
by Torvald Riegel.  Two copies of the supporting data structures are
used, also achieving full async-signal-safety.

Reviewed-by: Adhemerval Zanella  <adhemerval.zanella@linaro.org>
2021-12-28 22:52:56 +01:00
Adhemerval Zanella
063f9ba220 elf: Avoid unnecessary slowdown from profiling with audit (BZ#15533)
The rtld-audit interfaces introduces a slowdown due to enabling
profiling instrumentation (as if LD_AUDIT implied LD_PROFILE).
However, instrumenting is only necessary if one of audit libraries
provides PLT callbacks (la_pltenter or la_pltexit symbols).  Otherwise,
the slowdown can be avoided.

The following patch adjusts the logic that enables profiling to iterate
over all audit modules and check if any of those provides a PLT hook.
To keep la_symbind to work even without PLT callbacks, _dl_fixup now
calls the audit callback if the modules implements it.

Co-authored-by: Alexander Monakov <amonakov@ispras.ru>

Checked on x86_64-linux-gnu, i686-linux-gnu, and aarch64-linux-gnu.

Reviewed-by: Florian Weimer <fweimer@redhat.com>
2021-12-28 08:40:38 -03:00
Chung-Lin Tang
15a0c5730d elf: Fix slow DSO sorting behavior in dynamic loader (BZ #17645)
This second patch contains the actual implementation of a new sorting algorithm
for shared objects in the dynamic loader, which solves the slow behavior that
the current "old" algorithm falls into when the DSO set contains circular
dependencies.

The new algorithm implemented here is simply depth-first search (DFS) to obtain
the Reverse-Post Order (RPO) sequence, a topological sort. A new l_visited:1
bitfield is added to struct link_map to more elegantly facilitate such a search.

The DFS algorithm is applied to the input maps[nmap-1] backwards towards
maps[0]. This has the effect of a more "shallow" recursion depth in general
since the input is in BFS. Also, when combined with the natural order of
processing l_initfini[] at each node, this creates a resulting output sorting
closer to the intuitive "left-to-right" order in most cases.

Another notable implementation adjustment related to this _dl_sort_maps change
is the removing of two char arrays 'used' and 'done' in _dl_close_worker to
represent two per-map attributes. This has been changed to simply use two new
bit-fields l_map_used:1, l_map_done:1 added to struct link_map. This also allows
discarding the clunky 'used' array sorting that _dl_sort_maps had to sometimes
do along the way.

Tunable support for switching between different sorting algorithms at runtime is
also added. A new tunable 'glibc.rtld.dynamic_sort' with current valid values 1
(old algorithm) and 2 (new DFS algorithm) has been added. At time of commit
of this patch, the default setting is 1 (old algorithm).

Signed-off-by: Chung-Lin Tang  <cltang@codesourcery.com>
Reviewed-by: Adhemerval Zanella  <adhemerval.zanella@linaro.org>
2021-10-21 11:23:53 -03:00
H.J. Lu
b413280cfb ld.so: Replace DL_RO_DYN_SECTION with dl_relocate_ld [BZ #28340]
We can't relocate entries in dynamic section if it is readonly:

1. Add a l_ld_readonly field to struct link_map to indicate if dynamic
section is readonly and set it based on p_flags of PT_DYNAMIC segment.
2. Replace DL_RO_DYN_SECTION with dl_relocate_ld to decide if dynamic
section should be relocated.
3. Remove DL_RO_DYN_TEMP_CNT.
4. Don't use a static dynamic section to make readonly dynamic section
in vDSO writable.
5. Remove the temp argument from elf_get_dynamic_info.

This fixes BZ #28340.

Reviewed-by: Siddhesh Poyarekar <siddhesh@sourceware.org>
2021-09-22 11:12:43 -07:00
H.J. Lu
a93d9e03a3 Extend struct r_debug to support multiple namespaces [BZ #15971]
Glibc does not provide an interface for debugger to access libraries
loaded in multiple namespaces via dlmopen.

The current rtld-debugger interface is described in the file:

elf/rtld-debugger-interface.txt

under the "Standard debugger interface" heading.  This interface only
provides access to the first link-map (LM_ID_BASE).

1. Bump r_version to 2 when multiple namespaces are used.  This triggers
the GDB bug:

https://sourceware.org/bugzilla/show_bug.cgi?id=28236

2. Add struct r_debug_extended to extend struct r_debug into a linked-list,
where each element correlates to an unique namespace.
3. Initialize the r_debug_extended structure.  Bump r_version to 2 for
the new namespace and add the new namespace to the namespace linked list.
4. Add _dl_debug_update to return the address of struct r_debug' of a
namespace.
5. Add a hidden symbol, _r_debug_extended, for struct r_debug_extended.
6. Provide the symbol, _r_debug, with size of struct r_debug, as an alias
of _r_debug_extended, for programs which reference _r_debug.

This fixes BZ #15971.

Reviewed-by: Florian Weimer <fweimer@redhat.com>
2021-09-19 13:51:35 -07:00
Paul Eggert
2b778ceb40 Update copyright dates with scripts/update-copyrights
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
2021-01-02 12:17:34 -08:00
Florian Weimer
50b1b7a390 elf: Make __rtld_env_path_list and __rtld_search_dirs global variables
They have been renamed from env_path_list and rtld_search_dirs to
avoid linknamespace issues.

This change will allow future use these variables in diagnostics.

Reviewed-by: Adhemerval Zanella  <adhemerval.zanella@linaro.org>
2020-10-08 17:12:28 +02:00
Joseph Myers
d614a75396 Update copyright dates with scripts/update-copyrights. 2020-01-01 00:14:33 +00:00
Florian Weimer
f8ed116aa5 dlopen: Rework handling of pending NODELETE status
Commit a2e8aa0d9e ("Block signals during
the initial part of dlopen") was deemed necessary because of
read-modify-write operations like the one in  add_dependency in
elf/dl-lookup.c.  In the old code, we check for any kind of NODELETE
status and bail out:

      /* Redo the NODELETE check, as when dl_load_lock wasn't held
	 yet this could have changed.  */
      if (map->l_nodelete != link_map_nodelete_inactive)
	goto out;

And then set pending status (during relocation):

	  if (flags & DL_LOOKUP_FOR_RELOCATE)
	    map->l_nodelete = link_map_nodelete_pending;
	  else
	    map->l_nodelete = link_map_nodelete_active;

If a signal arrives during relocation and the signal handler, through
lazy binding, adds a global scope dependency on the same map, it will
set map->l_nodelete to link_map_nodelete_active.  This will be
overwritten with link_map_nodelete_pending by the dlopen relocation
code.

To avoid such problems in relation to the l_nodelete member, this
commit introduces two flags for active NODELETE status (irrevocable)
and pending NODELETE status (revocable until activate_nodelete is
invoked).  As a result, NODELETE processing in dlopen does not
introduce further reasons why lazy binding from signal handlers
is unsafe during dlopen, and a subsequent commit can remove signal
blocking from dlopen.

This does not address pre-existing issues (unrelated to the NODELETE
changes) which make lazy binding in a signal handler during dlopen
unsafe, such as the use of malloc in both cases.

Reviewed-by: Adhemerval Zanella <adhemerval.zanella@linaro.org>
Reviewed-by: Carlos O'Donell <carlos@redhat.com>
2019-12-13 10:18:46 +01:00
Florian Weimer
f63b73814f Remove all loaded objects if dlopen fails, ignoring NODELETE [BZ #20839]
This introduces a “pending NODELETE” state in the link map, which is
flipped to the persistent NODELETE state late in dlopen, via
activate_nodelete.    During initial relocation, symbol binding
records pending NODELETE state only.  dlclose ignores pending NODELETE
state.  Taken together, this results that a partially completed dlopen
is rolled back completely because new NODELETE mappings are unloaded.

Tested on x86_64-linux-gnu and i386-linux-gnu.

Change-Id: Ib2a3d86af6f92d75baca65431d74783ee0dbc292
2019-11-27 20:55:35 +01:00
Florian Weimer
e21a786771 Avoid zero-length array at the end of struct link_map [BZ #25097]
l_audit ends up as an internal array with _rtld_global, and GCC 10
warns about this.

This commit does not change the layout of _rtld_global, so it is
suitable for backporting.  Future changes could allocate more of the
audit state dynamically and remove it from always-allocated data
structures, to optimize the common case of inactive auditing.

Change-Id: Ic911100730f9124d4ea977ead8e13cee64b84d45
2019-11-15 13:03:59 +01:00
Paul Eggert
5a82c74822 Prefer https to http for gnu.org and fsf.org URLs
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
2019-09-07 02:43:31 -07:00
Joseph Myers
04277e02d7 Update copyright dates with scripts/update-copyrights.
* 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.
2019-01-01 00:11:28 +00:00
Tulio Magno Quites Machado Filho
e5d262effe Fix _dl_profile_fixup data-dependency issue (Bug 23690)
There is a data-dependency between the fields of struct l_reloc_result
and the field used as the initialization guard. Users of the guard
expect writes to the structure to be observable when they also observe
the guard initialized. The solution for this problem is to use an acquire
and release load and store to ensure previous writes to the structure are
observable if the guard is initialized.

The previous implementation used DL_FIXUP_VALUE_ADDR (l_reloc_result->addr)
as the initialization guard, making it impossible for some architectures
to load and store it atomically, i.e. hppa and ia64, due to its larger size.

This commit adds an unsigned int to l_reloc_result to be used as the new
initialization guard of the struct, making it possible to load and store
it atomically in all architectures. The fix ensures that the values
observed in l_reloc_result are consistent and do not lead to crashes.
The algorithm is documented in the code in elf/dl-runtime.c
(_dl_profile_fixup). Not all data races have been eliminated.

Tested with build-many-glibcs and on powerpc, powerpc64, and powerpc64le.

	[BZ #23690]
	* elf/dl-runtime.c (_dl_profile_fixup): Guarantee memory
	modification order when accessing reloc_result->addr.
	* include/link.h (reloc_result): Add field init.
	* nptl/Makefile (tests): Add tst-audit-threads.
	(modules-names): Add tst-audit-threads-mod1 and
	tst-audit-threads-mod2.
	Add rules to build tst-audit-threads.
	* nptl/tst-audit-threads-mod1.c: New file.
	* nptl/tst-audit-threads-mod2.c: Likewise.
	* nptl/tst-audit-threads.c: Likewise.
	* nptl/tst-audit-threads.h: Likewise.

Signed-off-by: Tulio Magno Quites Machado Filho <tuliom@linux.ibm.com>
Reviewed-by: Carlos O'Donell <carlos@redhat.com>
2018-11-30 18:05:32 -02:00
Joseph Myers
688903eb3e Update copyright dates with scripts/update-copyrights.
* 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.
2018-01-01 00:32:25 +00:00
H.J. Lu
4a306ef1c8 ld.so: Add architecture specific fields
To support Intel Control-flow Enforcement Technology (CET) run-time
control:

1. An architecture specific field in the writable ld.so namespace is
needed to indicate if CET features are enabled at run-time.
2. An architecture specific field in struct link_map is needed if
CET features are enabled in an ELF module.

This patch adds dl-procruntime.c to the writable ld.so namespace and
link_map.h to struct link_map.

Tested with build-many-glibcs.py.

	* elf/dl-support.c: Include <dl-procruntime.c>.
	* include/link.h: Include <link_map.h>.
	* sysdeps/generic/dl-procruntime.c: New file.
	* sysdeps/generic/link_map.h: Likewise.
	* sysdeps/generic/ldsodefs.h: Include <dl-procruntime.c> in
	the writable ld.so namespace.
2017-11-13 08:02:52 -08:00
H.J. Lu
a0aef7830e Move hidden_proto (__dl_iterate_phdr) to include/link.h [BZ #18822]
__dl_iterate_phdr is hidden and should be accessed directly within
libc.so and libc.a without using GOT nor PLT.

	[BZ #18822]
	* elf/dl-iteratephdr.c (hidden_proto (__dl_iterate_phdr)): Moved
	to ...
	* include/link.h (hidden_proto (__dl_iterate_phdr)): Here.
2017-10-01 16:09:38 -07:00
Joseph Myers
bfff8b1bec Update copyright dates with scripts/update-copyrights. 2017-01-01 00:14:16 +00:00
Zack Weinberg
4775578486 Installed header hygiene (BZ#20366): Test of installed headers.
This adds a test to ensure that the problems fixed in the last several
patches do not recur.  Each directory checks the headers that it
installs for two properties: first, each header must be compilable in
isolation, as both C and C++, under a representative combination of
language and library conformance levels; second, there is a blacklist
of identifiers that may not appear in any installed header, currently
consisting of the legacy BSD typedefs.  (There is an exemption for the
headers that define those typedefs, and for the RPC headers.  It may be
necessary to make this more sophisticated if we add more stuff to the
blacklist in the future.)

In order for this test to work correctly, every wrapper header
that actually defines something must guard those definitions with
 #ifndef _ISOMAC.  This is the existing mechanism used by the conform/
tests to tell wrapper headers not to define anything that the public
header wouldn't, and not to use anything from libc-symbols.h.  conform/
only cares for headers that we need to check for standards conformance,
whereas this test applies to *every* header.  (Headers in include/ that
are either installed directly, or are internal-use-only and do *not*
correspond to any installed header, are not affected.)

	* scripts/check-installed-headers.sh: New script.
	* Rules: In each directory that defines header files to be installed,
	run check-installed-headers.sh on them as a special test.
	* Makefile: Likewise for the headers installed at top level.

	* include/aliases.h, include/alloca.h, include/argz.h
	* include/arpa/nameser.h, include/arpa/nameser_compat.h
	* include/elf.h, include/envz.h, include/err.h
	* include/execinfo.h, include/fpu_control.h, include/getopt.h
	* include/gshadow.h, include/ifaddrs.h, include/libintl.h
	* include/link.h, include/malloc.h, include/mcheck.h
	* include/mntent.h, include/netinet/ether.h
	* include/nss.h, include/obstack.h, include/printf.h
	* include/pty.h, include/resolv.h, include/rpc/auth.h
	* include/rpc/auth_des.h, include/rpc/auth_unix.h
	* include/rpc/clnt.h, include/rpc/des_crypt.h
	* include/rpc/key_prot.h, include/rpc/netdb.h
	* include/rpc/pmap_clnt.h, include/rpc/pmap_prot.h
	* include/rpc/pmap_rmt.h, include/rpc/rpc.h
	* include/rpc/rpc_msg.h, include/rpc/svc.h
	* include/rpc/svc_auth.h, include/rpc/xdr.h
	* include/rpcsvc/nis_callback.h, include/rpcsvc/nislib.h
	* include/rpcsvc/yp.h, include/rpcsvc/ypclnt.h
	* include/rpcsvc/ypupd.h, include/shadow.h
	* include/stdio_ext.h, include/sys/epoll.h
	* include/sys/file.h, include/sys/gmon.h, include/sys/ioctl.h
	* include/sys/prctl.h, include/sys/profil.h
	* include/sys/statfs.h, include/sys/sysctl.h
	* include/sys/sysinfo.h, include/ttyent.h, include/utmp.h
	* sysdeps/arm/nacl/include/bits/setjmp.h
	* sysdeps/mips/include/sys/asm.h
	* sysdeps/unix/sysv/linux/include/sys/sysinfo.h
	* sysdeps/unix/sysv/linux/include/sys/timex.h
	* sysdeps/x86/fpu/include/bits/fenv.h:
	Add #ifndef _ISOMAC guard around internal declarations.
	Add multiple-inclusion guard if not already present.
2016-09-23 08:43:56 -04:00
Joseph Myers
f7a9f785e5 Update copyright dates with scripts/update-copyrights. 2016-01-04 16:05:18 +00:00
Joseph Myers
ec999b8e5e Move bits/libc-lock.h and bits/libc-lockP.h out of bits/ (bug 14912).
It was noted in
<https://sourceware.org/ml/libc-alpha/2012-09/msg00305.html> that the
bits/*.h naming scheme should only be used for installed headers.
This patch renames bits/libc-lock.h to plain libc-lock.h and
bits/libc-lockP.h to plain libc-lockP.h to follow that convention.

Note that I don't know where libc-lockP.h comes from for Hurd (the
Hurd libc-lock.h includes libc-lockP.h, but the only libc-lockP.h in
the glibc source tree is for NPTL) - some unmerged patch? - but I
updated the #include in the Hurd libc-lock.h anyway.

Tested for x86_64 (testsuite, and that installed stripped shared
libraries are unchanged by the patch).

	[BZ #14912]
	* bits/libc-lock.h: Move to ...
	* sysdeps/generic/libc-lock.h: ...here.
	(_BITS_LIBC_LOCK_H): Rename macro to _LIBC_LOCK_H.
	* sysdeps/mach/hurd/bits/libc-lock.h: Move to ...
	* sysdeps/mach/hurd/libc-lock.h: ...here.
	(_BITS_LIBC_LOCK_H): Rename macro to _LIBC_LOCK_H.
	[_LIBC]: Include <libc-lockP.h> instead of <bits/libc-lockP.h>.
	* sysdeps/mach/bits/libc-lock.h: Move to ...
	* sysdeps/mach/libc-lock.h: ...here.
	(_BITS_LIBC_LOCK_H): Rename macro to _LIBC_LOCK_H.
	* sysdeps/nptl/bits/libc-lock.h: Move to ...
	* sysdeps/nptl/libc-lock.h: ...here.
	(_BITS_LIBC_LOCK_H): Rename macro to _LIBC_LOCK_H.
	* sysdeps/nptl/bits/libc-lockP.h: Move to ...
	* sysdeps/nptl/libc-lockP.h: ...here.
	(_BITS_LIBC_LOCKP_H): Rename macro to _LIBC_LOCKP_H.
	* crypt/crypt_util.c: Include <libc-lock.h> instead of
	<bits/libc-lock.h>.
	* dirent/scandir-tail.c: Likewise.
	* dlfcn/dlerror.c: Likewise.
	* elf/dl-close.c: Likewise.
	* elf/dl-iteratephdr.c: Likewise.
	* elf/dl-lookup.c: Likewise.
	* elf/dl-open.c: Likewise.
	* elf/dl-support.c: Likewise.
	* elf/dl-writev.h: Likewise.
	* elf/rtld.c: Likewise.
	* grp/fgetgrent.c: Likewise.
	* gshadow/fgetsgent.c: Likewise.
	* gshadow/sgetsgent.c: Likewise.
	* iconv/gconv_conf.c: Likewise.
	* iconv/gconv_db.c: Likewise.
	* iconv/gconv_dl.c: Likewise.
	* iconv/gconv_int.h: Likewise.
	* iconv/gconv_trans.c: Likewise.
	* include/link.h: Likewise.
	* inet/getnameinfo.c: Likewise.
	* inet/getnetgrent.c: Likewise.
	* inet/getnetgrent_r.c: Likewise.
	* intl/bindtextdom.c: Likewise.
	* intl/dcigettext.c: Likewise.
	* intl/finddomain.c: Likewise.
	* intl/gettextP.h: Likewise.
	* intl/loadmsgcat.c: Likewise.
	* intl/localealias.c: Likewise.
	* intl/textdomain.c: Likewise.
	* libidn/idn-stub.c: Likewise.
	* libio/libioP.h: Likewise.
	* locale/duplocale.c: Likewise.
	* locale/freelocale.c: Likewise.
	* locale/newlocale.c: Likewise.
	* locale/setlocale.c: Likewise.
	* login/getutent_r.c: Likewise.
	* login/getutid_r.c: Likewise.
	* login/getutline_r.c: Likewise.
	* login/utmp-private.h: Likewise.
	* login/utmpname.c: Likewise.
	* malloc/mtrace.c: Likewise.
	* misc/efgcvt.c: Likewise.
	* misc/error.c: Likewise.
	* misc/fstab.c: Likewise.
	* misc/getpass.c: Likewise.
	* misc/mntent.c: Likewise.
	* misc/syslog.c: Likewise.
	* nis/nis_call.c: Likewise.
	* nis/nis_callback.c: Likewise.
	* nis/nss-default.c: Likewise.
	* nis/nss_compat/compat-grp.c: Likewise.
	* nis/nss_compat/compat-initgroups.c: Likewise.
	* nis/nss_compat/compat-pwd.c: Likewise.
	* nis/nss_compat/compat-spwd.c: Likewise.
	* nis/nss_nis/nis-alias.c: Likewise.
	* nis/nss_nis/nis-ethers.c: Likewise.
	* nis/nss_nis/nis-grp.c: Likewise.
	* nis/nss_nis/nis-hosts.c: Likewise.
	* nis/nss_nis/nis-network.c: Likewise.
	* nis/nss_nis/nis-proto.c: Likewise.
	* nis/nss_nis/nis-pwd.c: Likewise.
	* nis/nss_nis/nis-rpc.c: Likewise.
	* nis/nss_nis/nis-service.c: Likewise.
	* nis/nss_nis/nis-spwd.c: Likewise.
	* nis/nss_nisplus/nisplus-alias.c: Likewise.
	* nis/nss_nisplus/nisplus-ethers.c: Likewise.
	* nis/nss_nisplus/nisplus-grp.c: Likewise.
	* nis/nss_nisplus/nisplus-hosts.c: Likewise.
	* nis/nss_nisplus/nisplus-initgroups.c: Likewise.
	* nis/nss_nisplus/nisplus-network.c: Likewise.
	* nis/nss_nisplus/nisplus-proto.c: Likewise.
	* nis/nss_nisplus/nisplus-pwd.c: Likewise.
	* nis/nss_nisplus/nisplus-rpc.c: Likewise.
	* nis/nss_nisplus/nisplus-service.c: Likewise.
	* nis/nss_nisplus/nisplus-spwd.c: Likewise.
	* nis/ypclnt.c: Likewise.
	* nptl/libc_pthread_init.c: Likewise.
	* nss/getXXbyYY.c: Likewise.
	* nss/getXXent.c: Likewise.
	* nss/getXXent_r.c: Likewise.
	* nss/nss_db/db-XXX.c: Likewise.
	* nss/nss_db/db-netgrp.c: Likewise.
	* nss/nss_db/nss_db.h: Likewise.
	* nss/nss_files/files-XXX.c: Likewise.
	* nss/nss_files/files-alias.c: Likewise.
	* nss/nsswitch.c: Likewise.
	* posix/regex_internal.h: Likewise.
	* posix/wordexp.c: Likewise.
	* pwd/fgetpwent.c: Likewise.
	* resolv/res_hconf.c: Likewise.
	* resolv/res_libc.c: Likewise.
	* shadow/fgetspent.c: Likewise.
	* shadow/lckpwdf.c: Likewise.
	* shadow/sgetspent.c: Likewise.
	* socket/opensock.c: Likewise.
	* stdio-common/reg-modifier.c: Likewise.
	* stdio-common/reg-printf.c: Likewise.
	* stdio-common/reg-type.c: Likewise.
	* stdio-common/vfprintf.c: Likewise.
	* stdio-common/vfscanf.c: Likewise.
	* stdlib/abort.c: Likewise.
	* stdlib/cxa_atexit.c: Likewise.
	* stdlib/fmtmsg.c: Likewise.
	* stdlib/random.c: Likewise.
	* stdlib/setenv.c: Likewise.
	* string/strsignal.c: Likewise.
	* sunrpc/auth_none.c: Likewise.
	* sunrpc/bindrsvprt.c: Likewise.
	* sunrpc/create_xid.c: Likewise.
	* sunrpc/key_call.c: Likewise.
	* sunrpc/rpc_thread.c: Likewise.
	* sysdeps/arm/backtrace.c: Likewise.
	* sysdeps/generic/ldsodefs.h: Likewise.
	* sysdeps/generic/stdio-lock.h: Likewise.
	* sysdeps/generic/unwind-dw2-fde.c: Likewise.
	* sysdeps/i386/backtrace.c: Likewise.
	* sysdeps/ieee754/ldbl-opt/nldbl-compat.c: Likewise.
	* sysdeps/m68k/backtrace.c: Likewise.
	* sysdeps/mach/hurd/cthreads.c: Likewise.
	* sysdeps/mach/hurd/dirstream.h: Likewise.
	* sysdeps/mach/hurd/malloc-machine.h: Likewise.
	* sysdeps/nptl/malloc-machine.h: Likewise.
	* sysdeps/nptl/stdio-lock.h: Likewise.
	* sysdeps/posix/dirstream.h: Likewise.
	* sysdeps/posix/getaddrinfo.c: Likewise.
	* sysdeps/posix/system.c: Likewise.
	* sysdeps/pthread/aio_suspend.c: Likewise.
	* sysdeps/s390/s390-32/backtrace.c: Likewise.
	* sysdeps/s390/s390-64/backtrace.c: Likewise.
	* sysdeps/unix/sysv/linux/check_pf.c: Likewise.
	* sysdeps/unix/sysv/linux/if_index.c: Likewise.
	* sysdeps/unix/sysv/linux/s390/s390-32/getutent_r.c: Likewise.
	* sysdeps/unix/sysv/linux/s390/s390-32/getutid_r.c: Likewise.
	* sysdeps/unix/sysv/linux/s390/s390-32/getutline_r.c: Likewise.
	* sysdeps/unix/sysv/linux/shm-directory.c: Likewise.
	* sysdeps/unix/sysv/linux/system.c: Likewise.
	* sysdeps/x86_64/backtrace.c: Likewise.
	* time/alt_digit.c: Likewise.
	* time/era.c: Likewise.
	* time/tzset.c: Likewise.
	* wcsmbs/wcsmbsload.c: Likewise.
	* nptl/tst-initializers1.c (do_test): Refer to <libc-lock.h>
	instead of <bits/libc-lock.h> in comment.
2015-09-08 21:11:03 +00:00
Joseph Myers
522e02ab8a Rename bits/linkmap.h to linkmap.h (bug 14912).
It was noted in
<https://sourceware.org/ml/libc-alpha/2012-09/msg00305.html> that the
bits/*.h naming scheme should only be used for installed headers.
This patch renames bits/linkmap.h to plain linkmap.h to follow that
convention.

Tested for x86_64 (testsuite, and that installed stripped shared
libraries are unchanged by the patch).

	[BZ #14912]
	* bits/linkmap.h: Move to ...
	* sysdeps/generic/linkmap.h: ...here.
	* sysdeps/aarch64/bits/linkmap.h: Move to ...
	* sysdeps/aarch64/linkmap.h: ...here.
	* sysdeps/arm/bits/linkmap.h: Move to ...
	* sysdeps/arm/linkmap.h: ...here.
	* sysdeps/hppa/bits/linkmap.h: Move to ...
	* sysdeps/hppa/linkmap.h: ...here.
	* sysdeps/ia64/bits/linkmap.h: Move to ...
	* sysdeps/ia64/linkmap.h: ...here.
	* sysdeps/mips/bits/linkmap.h: Move to ...
	* sysdeps/mips/linkmap.h: ...here.
	* sysdeps/s390/bits/linkmap.h: Move to ...
	* sysdeps/s390/linkmap.h: ...here.
	* sysdeps/sh/bits/linkmap.h: Move to ...
	* sysdeps/sh/linkmap.h: ...here.
	* sysdeps/x86/bits/linkmap.h: Move to ...
	* sysdeps/x86/linkmap.h: ...here.
	* include/link.h: Include <linkmap.h> instead of <bits/linkmap.h>.
2015-09-04 19:44:27 +00:00
Siddhesh Poyarekar
90b37cac8b Also use l_tls_dtor_count to decide on object unload (BZ #18657)
When an TLS destructor is registered, we set the DF_1_NODELETE flag to
signal that the object should not be destroyed.  We then clear the
DF_1_NODELETE flag when all destructors are called, which is wrong -
the flag could have been set by other means too.

This patch replaces this use of the flag by using l_tls_dtor_count
directly to determine whether it is safe to unload the object.  This
change has the added advantage of eliminating the lock taking when
calling the destructors, which could result in a deadlock.  The patch
also fixes the test case tst-tls-atexit - it was making an invalid
dlclose call, which would just return an error silently.

I have also added a detailed note on concurrency which also aims to
justify why I chose the semantics I chose for accesses to
l_tls_dtor_count.  Thanks to Torvald for his help in getting me
started on this and (literally) teaching my how to approach the
problem.

Change verified on x86_64; the test suite does not show any
regressions due to the patch.

ChangeLog:

	[BZ #18657]
	* elf/dl-close.c (_dl_close_worker): Don't unload DSO if there
	are pending TLS destructor calls.
	* include/link.h (struct link_map): Add concurrency note for
	L_TLS_DTOR_COUNT.
	* stdlib/cxa_thread_atexit_impl.c (__cxa_thread_atexit_impl):
	Don't touch the link map flag.  Atomically increment
	l_tls_dtor_count.
	(__call_tls_dtors): Atomically decrement l_tls_dtor_count.
	Avoid taking the load lock and don't touch the link map flag.
	* stdlib/tst-tls-atexit-nodelete.c: New test case.
	* stdlib/Makefile (tests): Use it.
	* stdlib/tst-tls-atexit.c (do_test): dlopen
	tst-tls-atexit-lib.so again before dlclose.  Add conditionals
	to allow tst-tls-atexit-nodelete test case to use it.
2015-07-23 11:16:18 +05:30
Roland McGrath
c01ae97eb8 Factor file identity rules out of generic rtld code. 2015-07-14 13:15:26 -07:00
Joseph Myers
b168057aaa Update copyright dates with scripts/update-copyrights. 2015-01-02 16:29:47 +00:00
Allan McRae
d4697bc93d Update copyright notices with scripts/update-copyrights 2014-01-01 22:00:23 +10:00
Ryan S. Arnold
e054f49430 Add #include <stdint.h> for uint[32|64]_t usage (except installed headers). 2013-05-16 11:32:54 -05:00
Siddhesh Poyarekar
ba384f6ed9 C++11 thread_local destructors support
This feature is specifically for the C++ compiler to offload calling
thread_local object destructors on thread program exit, to glibc.
This is to overcome the possible complication of destructors of
thread_local objects getting called after the DSO in which they're
defined is unloaded by the dynamic linker.  The DSO is marked as
'unloadable' if it has a constructed thread_local object and marked as
'unloadable' again when all the constructed thread_local objects
defined in it are destroyed.
2013-02-18 19:08:21 +05:30
Jan Kratochvil
542f94662e Improve link_map.l_addr comment. 2013-02-02 10:29:17 +01:00
Joseph Myers
568035b787 Update copyright notices with scripts/update-copyrights. 2013-01-02 19:05:09 +00:00
Andreas Schwab
67cbf9a2a9 [BZ #14898]
* include/link.h (FORCED_DYNAMIC_TLS_OFFSET) [NO_TLS_OFFSET == 0]:
	Change to -1.
2012-12-07 14:55:19 -07:00
Andreas Schwab
0479b305c5 Fix invalid memory access in do_lookup_x.
[BZ #13579] Do not free l_initfini and allow it to be reused
on subsequent dl_open calls for the same library. This fixes
the invalid memory access in do_lookup_x when the previously
free'd l_initfini was accessed through l_searchlist when a
library had been opened for the second time.
2012-06-22 11:10:31 -07:00
H.J. Lu
81b035fe63 Replace Elf64_XXX with ElfW(XXX) in dl-irel.h 2012-03-22 10:17:05 -07:00
Paul Eggert
59ba27a63a Replace FSF snail mail address with URLs. 2012-02-09 23:18:22 +00:00
Andreas Schwab
4bff6e0175 Fix memory leak in dlopen with RTLD_NOLOAD. 2011-02-25 20:49:48 -05:00
Ulrich Drepper
4ad43b62d6 Fix handling of STB_GNU_UNIQUE in LD_TRACE_PRELINKING 2010-03-24 10:14:22 -07:00
Ulrich Drepper
2af6396817 Avoid ELF lookup race.
On some architectures the update of the l_used field in the lookup
functions races with setting the other bits in the bitfield.  Simply
avoid this and optimize use of l_used in general.
2009-12-15 12:32:27 -08:00
Ulrich Drepper
4c533566c2 * include/link.h (FORCED_DYNAMIC_TLS_OFFSET): Define.
* elf/dl-close.c (_dl_close): Check for it.
	* elf/dl-reloc.c (CHECK_STATIC_TLS): Likewise.
	(_dl_allocate_static_tls): Likewise.
	* elf/dl-tls.c (_dl_allocate_tls_init): Likewise.
	(__tls_get_addr): Protect from race conditions in setting l_tls_offset
	to it.
	* elf/tst-tls16.c: New file.
	* elf/tst-tlsmod16a.c: New file.
	* elf/tst-tlsmod16b.c: New file.
	* elf/Makefile: Add rules to build and run tst-tls16.
2008-01-17 20:20:00 +00:00
Ulrich Drepper
385b4cf4c5 * sysdeps/generic/ldsodefs.h (struct dl_scope_free_list): Store
void * pointers instead of struct link_map **.
	(_dl_scope_free): Change argument type to void *.
	* include/link.h (struct link_map): Change type of l_reldeps
	to struct link_map_reldeps, move l_reldepsact into that
	struct too.
	* elf/dl-deps.c: Include atomic.h.
	(_dl_map_object_deps): Only change l->l_initfini when it is
	fully populated, use _dl_scope_free for freeing it.  Optimize
	removal of libs from reldeps by using l_reserved flag, when
	some removal is needed, allocate a new list instead of
	reallocating and free the old with _dl_scope_free.  Adjust
	for l_reldeps and l_reldepsact changes.
	* elf/dl-lookup.c (add_dependency): Likewise.  Reorganize to allow
	searching in l_initfini and l_reldeps without holding dl_load_lock.
	* elf/dl-fini.c (_dl_sort_fini): Adjust for l_reldeps and
	l_reldepsact changes.
	* elf/dl-close.c (_dl_close_worker): Likewise.
	* elf/dl-open.c (_dl_scope_free): Change argument type to void *.
2007-09-29 06:58:31 +00:00
Ulrich Drepper
b90395e6e9 * sysdeps/generic/ldsodefs.h (DL_LOOKUP_GSCOPE_LOCK): New definition.
* elf/dl-runtime.c (_dl_fixup, _dl_profile_fixup): Or in
	DL_LOOKUP_GSCOPE_LOCK into flags after THREAD_GSCOPE_SET_FLAG ().
	* elf/dl-sym.c (do_sym): Likewise.
	* include/link.h (struct link_map): Add l_serial field.
	* elf/dl-object.c (_dl_new_object): Initialize l_serial.
	* elf/dl-lookup.c (add_dependency): Add flags argument.
	Remember map->l_serial, if DL_LOOKUP_GSCOPE_LOCK is among
	flags, use THREAD_GSCOPE_RESET_FLAG before and
	THREAD_GSCOPE_SET_FLAG after
	__rtld_lock_lock_recursive (GL(dl_load_lock)) to avoid deadlock.
	Don't dereference map until it has been found on some list.
	If map->l_serial changed, return -1.
2007-09-18 19:20:56 +00:00
Ulrich Drepper
e4eb675d0c * elf/dl-close.c (free_mem): Free _dl_scope_free_list.
2007-06-13  Jakub Jelinek  <jakub@redhat.com>

	* include/link.h: Don't include rtld-lowlevel.h.
	(struct link_map): Remove l_scope_lock.
	* sysdeps/generic/ldsodefs.h: Don't include rtld-lowlevel.h.
	(_dl_scope_free_list): New field (variable) in _rtld_global.
	(DL_LOOKUP_SCOPE_LOCK): Remove.
	(_dl_scope_free): New prototype.
	* elf/dl-runtime.c (_dl_fixup): Don't use __rtld_mrlock_*lock.
	Don't pass DL_LOOKUP_SCOPE_LOCK to _dl_lookup_symbol_x.
	(_dl_profile_fixup): Likewise.
	* elf/dl-sym.c (do_sym): Likewise.  Use wrapped _dl_lookup_symbol_x
	whenever !RTLD_SINGLE_THREAD_P, use THREAD_GSCOPE_SET_FLAG and
	THREAD_GSCOPE_RESET_FLAG around it.
	* elf/dl-close.c (_dl_close_worker): Don't use
	__rtld_mrlock_{change,done}.  Call _dl_scope_free on the old
	scope.  Make sure THREAD_GSCOPE_WAIT () happens if any old
	scopes were queued or if l_scope_mem has been abandoned.
	* elf/dl-open.c (_dl_scope_free): New function.
	(dl_open_worker): Use it.  Don't use __rtld_mrlock_{change,done}.
	* elf/dl-support.c (_dl_scope_free_list): New variable.
	* elf/dl-lookup.c (add_dependency): Remove flags argument.
	Remove DL_LOOKUP_SCOPE_LOCK handling.
	(_dl_lookup_symbol_x): Adjust caller.  Remove DL_LOOKUP_SCOPE_LOCK
	handling.
	* elf/dl-object.c (_dl_new_object): Don't use
	__rtld_mrlock_initialize.

2007-06-19  Ulrich Drepper  <drepper@redhat.com>
2007-06-20 03:19:13 +00:00
Ulrich Drepper
9be09e060f * sysdeps/generic/ldsodefs.h (rtld_global): Reorder some elements
to fill in holes
	(rtld_global_ro): Likewise.

2007-06-18  Jakub Jelinek  <jakub@redhat.com>

	* elf/dl-addr.c (_dl_addr): Skip PT_LOAD checking if l_contiguous.
	Move PT_LOAD checking to...
	(_dl_addr_inside_object): ... here, new function.
	* elf/dl-sym.c (do_sym): If not l_contiguous,
	call _dl_addr_inside_object.
	* elf/dl-iteratephdr.c (__dl_iterate_phdr): Likewise.
	* dlfcn/dlinfo.c (dlinfo_doit): Likewise.
	* elf/dl-open.c (dl_open_worker): Likewise.
	(_dl_addr_inside_object): New function if IS_IN_rtld.
	* elf/dl-load.c (_dl_map_object_from_fd): Set l_contiguous if no
	holes are present or are PROT_NONE protected.
	* include/link.h (struct link_map): Add l_contiguous field.
	* sysdeps/generic/ldsodefs.h (_dl_addr_inside_object): New prototype.
2007-06-19 22:59:48 +00:00
Ulrich Drepper
341c566f05 * sysdeps/unix/sysv/linux/tst-getcpu.c: New file.
* sysdeps/unix/sysv/linux/Makefile [subdir=posix] (tests): Add
	tst-getcpu.

	* include/link.h: Move l_version and l_nversion members around to
	fill gaps.
2007-05-11 06:39:07 +00:00