They are both used by __libc_freeres to free all library malloc
allocated resources to help tooling like mtrace or valgrind with
memory leak tracking.
The current scheme uses assembly markers and linker script entries
to consolidate the free routine function pointers in the RELRO segment
and to be freed buffers in BSS.
This patch changes it to use specific free functions for
libc_freeres_ptrs buffers and call the function pointer array directly
with call_function_static_weak.
It allows the removal of both the internal macros and the linker
script sections.
Checked on x86_64-linux-gnu, i686-linux-gnu, and aarch64-linux-gnu.
Reviewed-by: Carlos O'Donell <carlos@redhat.com>
When audit modules are loaded, ld.so initialization is not yet
complete, and rtld_active () returns false even though ld.so is
mostly working. Instead, the static dlopen hook is used, but that
does not work at all because this is not a static dlopen situation.
Commit 466c1ea15f ("dlfcn: Rework
static dlopen hooks") moved the hook pointer into _rtld_global_ro,
which means that separate protection is not needed anymore and the
hook pointer can be checked directly.
The guard for disabling libio vtable hardening in _IO_vtable_check
should stay for now.
Fixes commit 8e1472d2c1 ("ld.so:
Examine GLRO to detect inactive loader [BZ #20204]").
Reviewed-by: Adhemerval Zanella <adhemerval.zanella@linaro.org>
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
We stopped adding "Contributed by" or similar lines in sources in 2012
in favour of git logs and keeping the Contributors section of the
glibc manual up to date. Removing these lines makes the license
header a bit more consistent across files and also removes the
possibility of error in attribution when license blocks or files are
copied across since the contributed-by lines don't actually reflect
reality in those cases.
Move all "Contributed by" and similar lines (Written by, Test by,
etc.) into a new file CONTRIBUTED-BY to retain record of these
contributions. These contributors are also mentioned in
manual/contrib.texi, so we just maintain this additional record as a
courtesy to the earlier developers.
The following scripts were used to filter a list of files to edit in
place and to clean up the CONTRIBUTED-BY file respectively. These
were not added to the glibc sources because they're not expected to be
of any use in future given that this is a one time task:
https://gist.github.com/siddhesh/b5ecac94eabfd72ed2916d6d8157e7dchttps://gist.github.com/siddhesh/15ea1f5e435ace9774f485030695ee02
Reviewed-by: Carlos O'Donell <carlos@redhat.com>
They are no longer needed after everything has been moved into
libc. The _dl_vsym test has to be removed because the symbol
cannot be used outside libc anymore.
Reviewed-by: Adhemerval Zanella <adhemerval.zanella@linaro.org>
In dlerror_run, free corresponds to the local malloc in the
namespace, but GLRO (dl_catch_error) uses the malloc from the base
namespace. elf/tst-dlmopen-gethostbyname triggers this mismatch,
but it does not crash, presumably because of a fastbin deallocation.
Fixes commit c2059edce2 ("elf: Use
_dl_catch_error from base namespace in dl-libc.c [BZ #27646]") and
commit b2964eb1d9 ("dlfcn: Failures
after dlmopen should not terminate process [BZ #24772]").
dlerrror_run in elf/dl-libc.c needs to call GLRO (dl_catch_error)
from the base namespace, just like the exported dlerror
implementation.
Fixes commit b2964eb1d9 ("dlfcn:
Failures after dlmopen should not terminate process [BZ #24772]").
Reviewed-by: Siddhesh Poyarekar <siddhesh@sourceware.org>
Consolidate all hooks structures into a single one. There are
no static dlopen ABI concerns because glibc 2.34 already comes
with substantial ABI-incompatible changes in this area. (Static
dlopen requires the exact same dynamic glibc version that was used
for static linking.)
The new approach uses a pointer to the hooks structure into
_rtld_global_ro and initalizes it in __rtld_static_init. This avoids
a back-and-forth with various callback functions.
Reviewed-by: Adhemerval Zanella <adhemerval.zanella@linaro.org>
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
This commit adds a new _dl_open_hook entry for dlvsym and implements the
function using the existing dl_lookup_symbol_x function supplied by the
dynamic loader.
A new hook variable, _dl_open_hook2, is introduced, which should make
this change suitable for backporting: For old statically linked
binaries, __libc_dlvsym will always return NULL.
GLRO (_rtld_global_ro) is read-only after initialization and can
therefore not be patched at run time, unlike the hook table addresses
and their contents, so this is a desirable hardening feature.
The hooks are only needed if ld.so has not been initialized, and this
happens only after static dlopen (dlmopen uses a single ld.so object
across all namespaces).
Reviewed-by: Carlos O'Donell <carlos@redhat.com>
This change moves the main implementation of _dl_catch_error,
_dl_signal_error to libc.so, where TLS variables can be used
directly. This removes a writable function pointer from the
rtld_global variable.
For use during initial relocation, minimal implementations of these
functions are provided in ld.so. These are eventually interposed
by the libc.so implementations. This is implemented by compiling
elf/dl-error-skeleton.c twice, via elf/dl-error.c and
elf/dl-error-minimal.c.
As a side effect of this change, the static version of dl-error.c
no longer includes support for the
_dl_signal_cerror/_dl_receive_error mechanism because it is only
used in ld.so.
[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.
argument.
(_dl_lookup_symbol_x): Adjust caller.
* sysdeps/generic/ldsodefs.h (struct link_namespaces): Remove
_ns_global_scope.
* elf/rtld.c (dl_main): Don't initialize _ns_global_scope.
* elf/dl-libc.c: Revert l_scope name changes.
* elf/dl-load.c: Likewise.
* elf/dl-object.c: Likewise.
* elf/rtld.c: Likewise.
* elf/dl-close.c (_dl_close): Likewise.
* elf/dl-open.c (dl_open_worker): Likewise. If not SINGLE_THREAD_P,
always use __rtld_mrlock_{change,done}. Always free old scope list
here if not l_scope_mem.
* elf/dl-runtime.c (_dl_fixup, _dl_profile_fixup): Revert l_scope name
change. Never free scope list here. Just __rtld_mrlock_lock before
the lookup and __rtld_mrlock_unlock it after the lookup.
* elf/dl-sym.c: Likewise.
* include/link.h (struct r_scoperec): Remove.
(struct link_map): Replace l_scoperec with l_scope, l_scoperec_mem
with l_scope_mem and l_scoperec_lock with l_scope_lock.
Implement reference counting of scope records.
* elf/dl-close.c (_dl_close): Remove all scopes from removed objects
from the list in objects which remain. Always allocate new scope
record.
* elf/dl-open.c (dl_open_worker): When growing array for scopes,
don't resize, allocate a new one.
* elf/dl-runtime.c: Update reference counters before using a scope
array.
* elf/dl-sym.c: Likewise.
* elf/dl-libc.c: Adjust for l_scope name change.
* elf/dl-load.c: Likewise.
* elf/dl-object.c: Likewise.
* elf/rtld.c: Likewise.
* include/link.h: Inlcude <rtld-lowlevel.h>. Define struct
r_scoperec. Replace r_scope with pointer to r_scoperec structure.
Add l_scoperec_lock.
* sysdeps/generic/ldsodefs.h: Include <rtld-lowlevel.h>.
* sysdeps/generic/rtld-lowlevel.h: New file.
* include/atomic.h: Rename atomic_and to atomic_and_val and
atomic_or to atomic_or_val. Define new macros atomic_and and
atomic_or which do not return values.
* sysdeps/x86_64/bits/atomic.h: Define atomic_and and atomic_or.
Various cleanups.
* sysdeps/i386/i486/bits/atomic.h: Likewise.
real malloc in the catch object.
(_dl_catch_error): Forward information about malloc use to caller
in new parameter.
(_dl_out_of_memory): Make static.
* elf/dl-deps.c: Adjust callers of _dl_catch_error.
* elf/dl-libc.c: Likewise.
* elf/dl-open.c: Likewise.
* elf/rtld.c: Likewise.
Add new --audit option.
* sysdeps/generic/ldsodefs.h: Remove _dl_out_of_memory declaration.
(rtld_global_ro._dl_signal_error): Add new parameter.
* include/dlfcn.h (_dl_catch_error): Add new parameter.
* dlfcn/dlfcn.c (_dlerror_run): Pass additional parameter to
_dl_catch_error. Only free if the returned newly value says so.
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>
2004-03-06 Ulrich Drepper <drepper@redhat.com>
* elf/dl-lookup.c: We don't need for specialized lookup functions.
Combining the functionality does not slow down relocation processing,
it might even speed it up a little.
* sysdeps/generic/ldsodefs.h: Adjust prototypes for lookup function.
Add only one function pointer to rtlf_global_ro.
* elf/do-lookup.h: Replace #ifs with ifs.
* elf/dl-libc.c: Adjust _dl_lookup_* callers.
* elf/dl-reloc.c: Likewise.
* elf/dl-runtime.c: Likewise.
* elf/dl-sym.c: Likewise.
* elf/rtld.c: Likewise. Adjust _rtld_global_ro initialization.
* sysdeps/generic/ldsodefs.h (__rtld_local_attribute__,
__rtld_global_attribute__): Undef after use.
(_rtld_local_ro): Define __rtld_local_attribute__ with just hidden
if available.
* sysdeps/alpha/Subdirs: New file.
* sysdeps/alpha/soft-fp/Makefile: New file.
* sysdeps/alpha/soft-fp/Versions: New file.
* sysdeps/alpha/soft-fp/local-soft-fp.h: New file.
* sysdeps/alpha/soft-fp/ots_add.c: New file.
* sysdeps/alpha/soft-fp/ots_cmp.c: new file.
* sysdeps/alpha/soft-fp/ots_cmpe.c: New file.
* sysdeps/alpha/soft-fp/ots_cvtqux.c: New file.
* sysdeps/alpha/soft-fp/ots_cvtqx.c: New file.
* sysdeps/alpha/soft-fp/ots_cvttx.c: New file.
* sysdeps/alpha/soft-fp/ots_cvtxq.c: New file.
* sysdeps/alpha/soft-fp/ots_cvtxt.c: New file.
* sysdeps/alpha/soft-fp/ots_div.c: New file.
* sysdeps/alpha/soft-fp/ots_mul.c: New file.
* sysdeps/alpha/soft-fp/ots_nintxq.c: New file.
* sysdeps/alpha/soft-fp/ots_sub.c: New file.
2003-06-11 Jakub Jelinek <jakub@redhat.com>
* elf/Versions (libc): Add _dl_open_hook@GLIBC_PRIVATE.
* elf/dl-libc.c (struct dl_open_hook): New.
(_dl_open_hook): New variable.
(do_dlsym_private): New function.
(__libc_dlopen_mode) [!SHARED]: Lookup _dl_open_hook@GLIBC_PRIVATE
and initialize it if found.
(__libc_dlopen_mode) [SHARED]: If _dl_open_hook is non-NULL,
call dlopen_mode hook.
(__libc_dlsym) [SHARED]: If _dl_open_hook is non-NULL,
call dlsym hook.
(__libc_dlclose) [SHARED]: If _dl_open_hook is non-NULL,
call dlclose hook.
2002-11-19 Ulrich Drepper <drepper@redhat.com>
* include/dlfcn.h: __libc_dlopen is now a macro calling
__libc_dlopen_mode with the extra parameter RTLD_LAZY.
(__libc_dlopen_mode): New prototype.
* elf/dl-libc.c (__libc_dlopen_mode): Renamed from __libc_dlopen. Add
new parameter. Store new parameter in mode field of structure passed
to do_dlopen.
(struct do_dlopen_args): Add new field mode.
(do_dlopen): Pass mode from parameter structure to _dl_open.
* sysdeps/unix/sysv/linux/hppa/sys/ucontext.h:
Define mcontext_t as a sigcontext.
* manual/crypt.texi (Cryptographic Functions): Mention that
the MD5 one-way algorithm is compatible with BSD's.
