This supersedes the init_array sysdeps directory. It allows us to
check for ELF_INITFINI in both C and assembler code, and skip DT_INIT
and DT_FINI processing completely on newer architectures.
A new header file is needed because <dl-machine.h> is incompatible
with assembler code. <sysdep.h> is compatible with assembler code,
but it cannot be included in all assembler files because on some
architectures, it redefines register names, and some assembler files
conflict with that.
<elf-initfini.h> is replicated for legacy architectures which need
DT_INIT/DT_FINI support. New architectures follow the generic default
and disable it.
To improve GCC 10 compatibility, it is necessary to remove the l_audit
zero-length array from the end of struct link_map. In preparation of
that, this commit introduces an accessor function for the audit state,
so that it is possible to change the representation of the audit state
without adjusting the code that accesses it.
Tested on x86_64-linux-gnu. Built on i686-gnu.
Change-Id: Id815673c29950fc011ae5301d7cde12624f658df
Combine the four places where link maps are sorted into a single function.
This also moves the logic to skip the first map (representing the main
binary) to the callers.
Assembler code passes the address of _dl_fini to __libc_start_main,
whose function pointer argument lacks the attribute. This means
that calls could use the wrong ABI. Fortunately, for zero-parameter
void-returning functions, internal_function does not change ABI
on i386 (the only architecture which uses internal_function), so
this inconsistency was harmless (which is why it had not been
noticed so far).
In this case, extend_alloca is used to work around the lack of
deallocation on scope exit. A VLA is automatically deallocated in this
way, so it is the more fitting approach.
To implement this, it is necessary to eliminate the goto. In addition,
this change eliminates the trivially-true assert; the assert is always
skipped if nloaded > 0.
* elf/dl-fini.c (_dl_fini): Rewrite to use variable-length array
instead of extend_alloca. Change control flow to avoid a goto.
Remove assert which is trivially always true.
On hppa and ia64, the macro DL_AUTO_FUNCTION_ADDRESS() uses the
variable fptr[2] in it's own scope.
The content of fptr[] is thus undefined right after the macro exits.
Newer gcc's (>= 4.7) reuse the stack space of this variable triggering
a segmentation fault in dl-init.c:69.
To fix this we rewrite the macros to make the call directly to init
and fini without needing to pass back a constructed function pointer.
Resolves: #15465
The program name may be unavailable if the user application tampers
with argc and argv[]. Some parts of the dynamic linker caters for
this while others don't, so this patch consolidates the check and
fallback into a single macro and updates all users.
[BZ #13882]
* elf/dl-deps.c (_dl_map_object_deps): Fix cycle detection. Use
uint16_t for elements in the "seen" array to avoid char overflows.
* elf/dl-fini.c (_dl_sort_fini): Likewise.
* elf/dl-open.c (dl_open_worker): Likewise.
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 *.
function _dl_sort_fini.
(_dl_sort_fini): New function.
* sysdeps/generic/ldsodefs.h: Declare _dl_sort_fini.
* elf/dl-close.c (_dl_close): Call _dl_sort_fini before running
destructors to call them in the right order.
Change type of l_idx to int.
* elf/dl-close.c: Basically rewrite. Do not use l_opencount to
determine whether a DSO has to be unloaded. Instead compute this
in this function.
* elf/dl-deps.c: No need to manipulate l_opencount anymore.
* elf/dl-lookup.c: Likewise.
* elf/rtld.c: Likewise
* elf/dl-open.c: Likewise. Use l_init_called to determine whether
object was just loaded.
* elf/dl-fini.c: Bump l_direct_opencount instead of l_opencount.
* elf/dl-load.c (_dl_map_object_from_fd): Do not recognize DSO which
is about to be unloaded as a match.
(_dl_map_object): Likewise.
* elf/do-lookup.h (do_lookup_x): Do not look into DSO which is about
to be unloaded.
* elf/circleload1.c: Don't use l_opencount anymore.
* elf/neededtest.c: Likewise.
* elf/neededtest2.c: Likewise.
* elf/neededtest3.c: Likewise.
* elf/neededtest4.c: Likewise.
* elf/unload.c: Likewise.
* elf/unload2.c: Likewise.
* elf/loadtest.c: Likewise.
* elf/rtld.c: Preloading errors are now never fatal.
2005-03-08 Jakub Jelinek <jakub@redhat.com>
* elf/Makefile: Add rules to build and run unload5 test.
* elf/unload5.c: New file.
2005-03-08 Jakub Jelinek <jakub@redhat.com>
* elf/Makefile: Add rules to build and run unload4 test.
* elf/unload4.c: New file.
* elf/unload4mod1.c: New file.
* elf/unload4mod2.c: New file.
* elf/unload4mod3.c: New file.
* elf/unload4mod4.c: New file.
2004-10-27 Ulrich Drepper <drepper@redhat.com>
* elf/dl-fini.c (_dl_fini): Fix search for map in maps array.
Reverse order of namespaces.
* elf/Makefile: Add rules to build and run tst-dlmopen3.
* elf/tst-dlmopen3.c: New file.
* elf/tst-dlmopen1mod.c: Add check whether constructor runs.
Update.
Add support for namespaces in the dynamic linker.
* dlfcn/Makefile (libdl-routines): Add dlmopen.
* dlfcn/Versions [libdl, GLIBC_2.3.4]: Add dlmopen.
* dlfcn/dlfcn.h: Define Lmid_t, LM_ID_BASE, and LM_ID_NEWLM.
Declare dlmopen. Document RTLD_DI_LMID.
* dlfcn/dlinfo.c: Handle RTLD_DI_LMID.
* dlfcn/dlmopen.c: New file.
* dlfcn/dlopen.c: Pass new parameter to _dl_open.
* dlfcn/dlopenold.c: Likewise.
* elf/dl-addr.c: Adjust for removal of GL(dl_loaded).
* elf/dl-caller.c: Likewise.
* elf/dl-close.c: Likewise.
* elf/dl-conflict.c: Likewise.
* elf/dl-debug.c: Likewise.
* elf/dl-lookup.c: Likewise.
* elf/dl-sym.c: Likewise.
* elf/dl-version.c: Likewise.
* elf/do-lookup.h: Likewise.
* elf/rtld.c: Likewise.
* sysdeps/unix/sysv/linux/i386/dl-librecon.h: Likewise.
* elf/dl-depsc: Likewise. Add new parameter to _dl_map_object.
* elf/dl-fini.c: Call destructors in all namespaces.
* elf/dl-iteratephdr.c: Compute total nloaded. Adjust for removal of
GL(dl_loaded).
* elf/dl-libc.c: Pass new parameter to _dl_open. Adjust for removal
of GL(dl_loaded).
* elf/dl-load.c (_dl_map_object_from_fd): Don't load ld.so a second
time. Reuse the one from the main namespace in all others.
Pass new parameter to _dl_new_object.
Adjust for removal of GL(dl_loaded).
* elf/dl-object.c: Take new parameter. Use it to initialize l_ns.
Adjust for removal of GL(dl_loaded).
* elf/dl-open.c (_dl_open): Take new parameter.
Adjust for removal of GL(dl_loaded).
* elf/dl-support.c: Replace global _dl_loaded etc variables with
_dl_ns variable.
* include/dlfcn.h: Adjust prototype of _dl_open.
Define __LM_ID_CALLER.
* include/link.h: Add l_real, l_ns, and l_direct_opencount elements.
* sysdeps/generic/dl-tls.c: Bump TLS_STATIC_SURPLUS. Since libc is
using TLS we need memory appropriate to the number of namespaces.
* sysdeps/generic/ldsodefs.h (struct rtld_global): Replace _dl_loaded,
_dl_nloaded, _dl_global_scope, _dl_main_searchlist, and
_dl_global_scope_alloc with _dl_ns element. Define DL_NNS.
Adjust prototypes of _dl_map_object and member in rtld_global_ro.
* malloc/malloc.c: Include <dlfcn.h>.
* malloc/arena.c (ptmalloc_init): If libc is not in primary namespace,
never use brk.
* elf/Makefile: Add rules to build and run tst-dlmopen1 and
tst-dlmopen2.
* elf/tst-dlmopen1.c: New file.
* elf/tst-dlmopen1mod.c: New file.
* elf/tst-dlmopen2.c: New file.
* elf/dl-close.c: Improve reference counting by tracking direct loads.
* elf/dl-lookup.c (add_dependency): Likewise.
* elf/dl-open.c (dl_open_worker): Likewise.
* elf/rtld.c (dl_main): Likewise.
2004-09-09 GOTO Masanori <gotom@debian.or.jp>
[BZ #77]
* elf/dl-close.c: Count down l_opencount to check not only for
l_reldeps, but also l_initfini.
2004-10-13 Ulrich Drepper <drepper@redhat.com>
2004-02-20 Ulrich Drepper <drepper@redhat.com>
* dlfcn/dlsym.c: Get ld.so loading lock before the call into ld.so.
* dlfcn/dlvsym.c: Likewise.
* elf/dl-addr.c: Get loading lock while using _dl_loaded data.
* elf/dl-fini.c: Likewise.
Patch by Shunichi Sagawa <s-sagawa@jp.fujitsu.com>.
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.