The changes in commit a93d9e03a3
("Extend struct r_debug to support multiple namespaces [BZ #15971]")
break the dyninst dynamic instrumentation tool. It brings its
own definition of _r_debug (rather than a declaration).
Furthermore, it turns out it is rather hard to use the proposed
handshake for accessing _r_debug via DT_DEBUG. If applications want
to access _r_debug, they can do so directly if the relevant code has
been built as PIC. To protect against harm from accidental copy
relocations due to linker relaxations, this commit restores copy
relocation support by adjusting both copies if interposition or
copy relocations are in play. Therefore, it is possible to
use a hidden reference in ld.so to access _r_debug.
Only perform the copy relocation initialization if libc has been
loaded. Otherwise, the ld.so search scope can be empty, and the
lookup of the _r_debug symbol mail fail.
Reviewed-by: H.J. Lu <hjl.tools@gmail.com>
It combines updating r_state with the debugger notification.
The second change to _dl_open introduces an additional debugger
notification for dlmopen, but debuggers are expected to ignore it.
Reviewed-by: H.J. Lu <hjl.tools@gmail.com>
It replaces the ns_debug member of the namespaces. Previously,
the base namespace had an unused ns_debug member.
This change also fixes a concurrency issue: Now _dl_debug_initialize
only updates r_next of the previous namespace's r_debug after the new
r_debug is initialized, so that only the initialized version is
observed. (Client code accessing _r_debug will benefit from load
dependency tracking in CPUs even without explicit barriers.)
Reviewed-by: H.J. Lu <hjl.tools@gmail.com>
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
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>
I used these shell commands:
../glibc/scripts/update-copyrights $PWD/../gnulib/build-aux/update-copyright
(cd ../glibc && git commit -am"[this commit message]")
and then ignored the output, which consisted lines saying "FOO: warning:
copyright statement not found" for each of 6694 files FOO.
I then removed trailing white space from benchtests/bench-pthread-locks.c
and iconvdata/tst-iconv-big5-hkscs-to-2ucs4.c, to work around this
diagnostic from Savannah:
remote: *** pre-commit check failed ...
remote: *** error: lines with trailing whitespace found
remote: error: hook declined to update refs/heads/master
rather than r->r_brk.
2006-11-08 Jakub Jelinek <jakub@redhat.com>
* elf/dl-load.c (decompose_rpath): Return bool rather than void.
If l->l_name is on inhibit_rpath list, set sps->dirs to -1 and
return false, otherwise return true.
(cache_rpath): Return decompose_rpath return value.
2006-11-07 Jakub Jelinek <jakub@redhat.com>
* include/libc-symbols.h (declare_symbol): Rename to...
(declare_symbol_alias): ... this. Add ORIGINAL argument, imply
strong_alias (ORIGINAL, SYMBOL) in asm to make sure it preceedes
.size directive.
* sysdeps/gnu/errlist-compat.awk: Adjust for declare_symbol_alias
changes.
* sysdeps/gnu/siglist.c: Likewise.
* elf/Makefile (tests): Add it.
($(objpfx)tst-tls-dlinfo): Depend on $(libdl).
($(objpfx)tst-tls-dlinfo.out): Depend on $(objpfx)tst-tlsmod2.so.
* dlfcn/dlfcn.h (RTLD_DI_PROFILENAME, RTLD_DI_PROFILEOUT): New enum
values, reserve unsupported requested names used on Solaris.
(RTLD_DI_TLS_MODID, RTLD_DI_TLS_DATA): New enum values.
(RTLD_DI_MAX): Likewise.
* dlfcn/dlinfo.c (dlinfo_doit): Handle RTLD_DI_TLS_MODID and
RTLD_DI_TLS_DATA.
* elf/dl-tls.c (_dl_tls_get_addr_soft): New function.
* sysdeps/generic/ldsodefs.h: Declare it.
* elf/Versions (ld: GLIBC_PRIVATE): Add it.
* elf/link.h (struct dl_phdr_info): New members dlpi_tls_modid,
dlpi_tls_data.
* elf/dl-iteratephdr.c (__dl_iterate_phdr): Fill them in.
* include/link.h: Don't copy contents from elf/link.h.
Instead, #include it while #define'ing around link_map.
* elf/dl-debug.c (_dl_debug_initialize): Add a cast.
Add bogus extern decl to verify link_map members.
* elf/loadtest.c (MAPS): New macro, cast _r_debug._r_map.
(OUT, main): Use it in place of _r_debug._r_map.
* elf/unload.c: Likewise.
* elf/unload2.c: Likewise.
* elf/neededtest.c (check_loaded_objects): Likewise.
* elf/neededtest2.c (check_loaded_objects): Likewise.
* elf/neededtest3.c (check_loaded_objects): Likewise.
* elf/neededtest4.c (check_loaded_objects): Likewise.
* elf/circleload1.c (check_loaded_objects): Likewise.
2005-01-09 Ulrich Drepper <drepper@redhat.com>
* elf/dl-debug.c (_dl_debug_initialize): Take extra parameter and
use it to select the r_debug structure for that namespace.
* elf/dl-close.c (_dl_close): Adjust call to _dl_debug_initialize.
* elf/dl-load.c (_dl_map_object_from_fd): Likewise.
* elf/dl-open.c (_dl_open): Likewise.
* elf/rtld.c (dl_main): Likewise.
* sysdeps/generic/ldsodefs.h (struct link_namespaces): Add _ns_debug
member.
(_dl_debug_initialize): Add new parameter in declaration.
* elf/dl-close.c (_dl_close): Make sure auditing callbacks are not
called for the auditing objects themselves.
* elf/dl-load.c (_dl_map_object_from_fd): Likewise.
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>
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.
* time/strftime.c (strftime: do_number): Adjust P and I after sprintf
in case it wrote fewer than MAXDIGITS chars.
* stdio/fwrite.c (fwrite: fill_buffer): Separate flushing for last
newline from flushing full buffer in loop, fix test so no fflush is
done when last byte written exactly fills the buffer.
* nss/Makefile ($(services:%=$(objpfx)libnss_%.so)): Depend on libc.so.
* sysdeps/mach/hurd/Makefile (LDLIBS-c.so): Variable removed.
(libc.so): Instead, give this deps on lib{mach,hurd}user.so.
* elf/dl-debug.c (_dl_debug_initialize): Use LDBASE arg instead of
extracting _dl_rtld_map.l_addr.
* sysdeps/i386/dl-machine.h (elf_machine_rel): Declare _dl_rtld_map as
weak.
* sysdeps/alpha/dl-machine.h (elf_machine_rela): Likewise.
* shlib-versions (*-*-*): Set libnss_db=1.
* elf/rtld.c (dl_main): Set _dl_rtld_map's DT_DEBUG location too.
* elf/dl-lookup.c (_dl_lookup_symbol): If no value and *REF is
null, consider it a strong reference and give the error.
Wed Jun 12 15:52:46 1996 Roland McGrath <roland@delasyd.gnu.ai.mit.edu>
* elf/dl-open.c (_dl_open): Correctly terminate relocating loop
after relocating NEW when it's the only new object.
* elf/dl-init.c (_dl_init_next): When out of initializers, set
_r_debug.r_state to RT_CONSISTENT and call _dl_debug_state just
before return.
* elf/rtld.c (dl_main): Move _dl_debug_initialize call after
relocation. Call it unconditionally and only fill in DT_DEBUG
if it's present. Then call _dl_debug_state with r_state RT_ADD
before running initializers.
* elf/dl-open.c (_dl_open): Call _dl_debug_initialize and then call
_dl_debug_state with r_state RT_ADD before running initializers
* elf/dl-close.c (_dl_close): Call _dl_debug_state with r_state
RT_DELETE before running finalizers and with RT_CONSISTENT just
before return.
* elf/Makefile (dl-routines): Add dl-debug.
* elf/dl-debug.c: New file.
* elf/rtld.c (_dl_r_debug): Rename to _r_debug and move to dl-debug.c.
(_dl_r_debug_state): Rename to _dl_debug_state and likewise move.
(dl_main): Use _dl_debug_initialize.
* elf/link.h: Fix name to _dl_debug_state in decl.
(_dl_debug_initialize): Declare new function from dl-debug.c.
(_r_debug): Declare it.
* Makerules (distinfo-vars): Add install-{lib,data,bin,sbin,others}.
In distinfo set $(subdir)-VAR and then set VAR to $($(subdir)-VAR).
* Makeconfig (rpath-link): New variable; add $(elfobjdir).
(default-rpath): Use it.
(built-program-cmd): Use it in LD_LIBRARY_PATH.
* Makeconfig (sysdep-configures): Prepend $(sysdep_dir) to names tried.
* sysdeps/unix/Dist: Add make-syscalls.sh.
* misc/Makefile (headers): Add sys/swap.h.
* posix/unistd.h: Remove decls for swapon, swapoff.
* sysdeps/generic/sys/swap.h: New file.
* sysdeps/unix/sysv/linux/sys/swap.h: New file.
* sysdeps/unix/sysv/linux/gnu/types.h: Remove temporary hack #define
of __kernel_fsid_t. It is correctly defines in <linux/types.h> now.
