Commit Graph

653 Commits

Author SHA1 Message Date
Florian Weimer
ede8d94d15 csu: Implement and use _dl_early_allocate during static startup
This implements mmap fallback for a brk failure during TLS
allocation.

scripts/tls-elf-edit.py is updated to support the new patching method.
The script no longer requires that in the input object is of ET_DYN
type.

Reviewed-by: Adhemerval Zanella  <adhemerval.zanella@linaro.org>
(cherry picked from commit f787e138aa)
2022-05-19 12:13:53 +02:00
Florian Weimer
ff900fad89 Linux: Consolidate auxiliary vector parsing (redo)
And optimize it slightly.

This is commit 8c8510ab27 revised.

In _dl_aux_init in elf/dl-support.c, use an explicit loop
and -fno-tree-loop-distribute-patterns to avoid memset.

Reviewed-by: Szabolcs Nagy <szabolcs.nagy@arm.com>
(cherry picked from commit 73fc4e28b9)
2022-05-19 12:13:51 +02:00
Florian Weimer
bc56ab1f4a dlfcn: Do not use rtld_active () to determine ld.so state (bug 29078)
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>
(cherry picked from commit 8dcb6d0af0)
2022-04-26 15:28:39 +02:00
Florian Weimer
f0c71b34f9 Default to --with-default-link=no (bug 25812)
This is necessary to place the libio vtables into the RELRO segment.
New tests elf/tst-relro-ldso and elf/tst-relro-libc are added to
verify that this is what actually happens.

The new tests fail on ia64 due to lack of (default) RELRO support
inbutils, so they are XFAILed there.

(cherry picked from commit 198abcbb94)
2022-04-22 11:31:14 +02:00
Florian Weimer
3e0a91b79b scripts: Add glibcelf.py module
Hopefully, this will lead to tests that are easier to maintain.  The
current approach of parsing readelf -W output using regular expressions
is not necessarily easier than parsing the ELF data directly.

This module is still somewhat incomplete (e.g., coverage of relocation
types and versioning information is missing), but it is sufficient to
perform basic symbol analysis or program header analysis.

The EM_* mapping for architecture-specific constant classes (e.g.,
SttX86_64) is not yet implemented.  The classes are defined for the
benefit of elf/tst-glibcelf.py.

Reviewed-by: Siddhesh Poyarekar <siddhesh@sourceware.org>
(cherry picked from commit 30035d6772)
2022-04-22 11:28:57 +02:00
Stefan Liebler
0c03cb54c8 S390: Add new s390 platform z16.
The new IBM z16 is added to platform string array.
The macro _DL_PLATFORMS_COUNT is incremented.

_dl_hwcaps_subdir is extended by "z16" if HWCAP_S390_VXRS_PDE2
is set. HWCAP_S390_NNPA is not tested in _dl_hwcaps_subdirs_active
as those instructions may be replaced or removed in future.

tst-glibc-hwcaps.c is extended in order to test z16 via new marker5.

A fatal glibc error is dumped if glibc was build with architecture
level set for z16, but run on an older machine. (See dl-hwcap-check.h)

(cherry picked from commit 2376944b9e)
2022-04-14 14:21:57 +02:00
Adhemerval Zanella
4dca2d3a7b hppa: Fix bind-now audit (BZ #28857)
On hppa, a function pointer returned by la_symbind is actually a function
descriptor has the plabel bit set (bit 30).  This must be cleared to get
the actual address of the descriptor.  If the descriptor has been bound,
the first word of the descriptor is the physical address of theA function,
otherwise, the first word of the descriptor points to a trampoline in the
PLT.

This patch also adds a workaround on tests because on hppa (and it seems
to be the only ABI I have see it), some shared library adds a dynamic PLT
relocation to am empty symbol name:

$ readelf -r elf/tst-audit25mod1.so
[...]
Relocation section '.rela.plt' at offset 0x464 contains 6 entries:
 Offset     Info    Type            Sym.Value  Sym. Name + Addend
00002008  00000081 R_PARISC_IPLT                508
[...]

It breaks some assumptions on the test, where a symbol with an empty
name ("") is passed on la_symbind.

Checked on x86_64-linux-gnu and hppa-linux-gnu.

(cherry picked from commit 9e94f57484)
2022-04-12 13:33:17 -04:00
H.J. Lu
aabdad371f elf: Replace tst-audit24bmod2.so with tst-audit24bmod2
Replace tst-audit24bmod2.so with tst-audit24bmod2 to silence:

make[2]: Entering directory '/export/gnu/import/git/gitlab/x86-glibc/elf'
Makefile:2201: warning: overriding recipe for target '/export/build/gnu/tools-build/glibc-gitlab/build-x86_64-linux/elf/tst-audit24bmod2.so'
../Makerules:765: warning: ignoring old recipe for target '/export/build/gnu/tools-build/glibc-gitlab/build-x86_64-linux/elf/tst-audit24bmod2.so'

(cherry picked from commit fa7ad1df19)
2022-04-12 13:33:17 -04:00
Szabolcs Nagy
165e7ad459 Fix elf/tst-audit25a with default bind now toolchains
This test relies on lazy binding for the executable so request that
explicitly in case the toolchain defaults to bind now.

(cherry picked from commit 80a08d0faa)
2022-04-12 13:33:17 -04:00
Adhemerval Zanella
056fc1c0e3 elf: Issue la_symbind for bind-now (BZ #23734)
The audit symbind callback is not called for binaries built with
-Wl,-z,now or when LD_BIND_NOW=1 is used, nor the PLT tracking callbacks
(plt_enter and plt_exit) since this would change the expected
program semantics (where no PLT is expected) and would have performance
implications (such as for BZ#15533).

LAV_CURRENT is also bumped to indicate the audit ABI change (where
la_symbind flags are set by the loader to indicate no possible PLT
trace).

To handle powerpc64 ELFv1 function descriptor, _dl_audit_symbind
requires to know whether bind-now is used so the symbol value is
updated to function text segment instead of the OPD (for lazy binding
this is done by PPC64_LOAD_FUNCPTR on _dl_runtime_resolve).

Checked on x86_64-linux-gnu, i686-linux-gnu, aarch64-linux-gnu,
powerpc64-linux-gnu.

Reviewed-by: Carlos O'Donell <carlos@redhat.com>
Tested-by: Carlos O'Donell <carlos@redhat.com>
(cherry picked from commit 32612615c5)

Resolved conflicts:
	NEWS - Manual merge.
2022-04-12 13:32:59 -04:00
Adhemerval Zanella
efb21b5fb2 elf: Fix initial-exec TLS access on audit modules (BZ #28096)
For audit modules and dependencies with initial-exec TLS, we can not
set the initial TLS image on default loader initialization because it
would already be set by the audit setup.  However, subsequent thread
creation would need to follow the default behaviour.

This patch fixes it by setting l_auditing link_map field not only
for the audit modules, but also for all its dependencies.  This is
used on _dl_allocate_tls_init to avoid the static TLS initialization
at load time.

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

Reviewed-by: Carlos O'Donell <carlos@redhat.com>
Tested-by: Carlos O'Donell <carlos@redhat.com>
(cherry picked from commit 254d3d5aef)
2022-04-08 14:18:12 -04:00
Adhemerval Zanella
98047ba95c elf: Add la_activity during application exit
la_activity is not called during application exit, even though
la_objclose is.

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

Reviewed-by: Carlos O'Donell <carlos@redhat.com>
Tested-by: Carlos O'Donell <carlos@redhat.com>
(cherry picked from commit 5fa11a2bc9)
2022-04-08 14:18:12 -04:00
Adhemerval Zanella
2255621f0e elf: Do not fail for failed dlmopen on audit modules (BZ #28061)
The dl_main sets the LM_ID_BASE to RT_ADD just before starting to
add load new shared objects.  The state is set to RT_CONSISTENT just
after all objects are loaded.

However if a audit modules tries to dlmopen an inexistent module,
the _dl_open will assert that the namespace is in an inconsistent
state.

This is different than dlopen, since first it will not use
LM_ID_BASE and second _dl_map_object_from_fd is the sole responsible
to set and reset the r_state value.

So the assert on _dl_open can not really be seen if the state is
consistent, since _dt_main resets it.  This patch removes the assert.

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

Reviewed-by: Florian Weimer <fweimer@redhat.com>
(cherry picked from commit 484e672dda)

Resolved conflicts:
	elf/Makefile
	elf/dl-open.c
2022-04-08 14:18:12 -04:00
Adhemerval Zanella
d1b9bee29a elf: Issue audit la_objopen for vDSO
The vDSO is is listed in the link_map chain, but is never the subject of
an la_objopen call.  A new internal flag __RTLD_VDSO is added that
acts as __RTLD_OPENEXEC to allocate the required 'struct auditstate'
extra space for the 'struct link_map'.

The return value from the callback is currently ignored, since there
is no PLT call involved by glibc when using the vDSO, neither the vDSO
are exported directly.

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

Reviewed-by: Florian Weimer <fweimer@redhat.com>
(cherry picked from commit f0e23d34a7)

Resolved conflicts:
	elf/Makefile
2022-04-08 14:18:12 -04:00
Adhemerval Zanella
02c6a3d353 elf: Add audit tests for modules with TLSDESC
Checked on x86_64-linux-gnu, i686-linux-gnu, and aarch64-linux-gnu.

Reviewed-by: Florian Weimer <fweimer@redhat.com>
(cherry picked from commit d1b38173c9)
2022-04-08 14:18:12 -04:00
Adhemerval Zanella
29496b3103 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>
(cherry picked from commit 063f9ba220)

Resolved conflicts:
	NEWS
	elf/Makefile
2022-04-08 14:18:12 -04:00
Adhemerval Zanella
ce0cb6d1d2 elf: Add _dl_audit_objopen
It consolidates the code required to call la_objopen audit callback.

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

Reviewed-by: Florian Weimer <fweimer@redhat.com>
(cherry picked from commit aee6e90f93)

Resolved conflicts:
	elf/Makefile
2022-04-08 14:18:11 -04:00
Adhemerval Zanella
e25fe99213 elf: Move la_activity (LA_ACT_ADD) after _dl_add_to_namespace_list() (BZ #28062)
It ensures that the the namespace is guaranteed to not be empty.

Checked on x86_64-linux-gnu.

Reviewed-by: Florian Weimer <fweimer@redhat.com>
(cherry picked from commit ed3ce71f5c)

Resolved conflicts:
	elf/Makefile
2022-04-08 14:18:11 -04:00
Adhemerval Zanella
a31bbe3242 elf: Move LAV_CURRENT to link_lavcurrent.h
No functional change.

(cherry picked from commit 54816ae98d)

Resolved conflicts:
	elf/Makefile
2022-04-08 14:18:11 -04:00
Florian Weimer
948ebc098e Fix glibc 2.34 ABI omission (missing GLIBC_2.34 in dynamic loader)
The glibc 2.34 release really should have added a GLIBC_2.34
symbol to the dynamic loader. With it, we could move functions such
as dlopen or pthread_key_create that work on process-global state
into the dynamic loader (once we have fixed a longstanding issue
with static linking).  Without the GLIBC_2.34 symbol, yet another
new symbol version would be needed because old glibc will fail to
load binaries due to the missing symbol version in ld.so that newly
linked programs will require.

Reviewed-by: H.J. Lu <hjl.tools@gmail.com>
(cherry picked from commit af121ae3e7)
2022-01-31 14:58:02 +01:00
Florian Weimer
de6cdd6875 elf/Makefile: Reflow and sort most variable assignments
Reviewed-by: H.J. Lu <hjl.tools@gmail.com>
(cherry picked from commit 7de01e60c2)
2022-01-31 14:57:00 +01:00
H.J. Lu
511b244cc5 elf: Add a comment after trailing backslashes
(cherry picked from commit f4f70c2895)
2022-01-31 14:26:45 +01:00
H.J. Lu
31186e2cb7 elf: Sort tests and modules-names
Sort tests and modules-names to reduce future conflicts.

(cherry picked from commit 28713c0612)
2022-01-31 14:26:38 +01:00
H.J. Lu
6548a9bdba Avoid warning: overriding recipe for .../tst-ro-dynamic-mod.so
Add tst-ro-dynamic-mod to modules-names-nobuild to avoid

../Makerules:767: warning: ignoring old recipe for target '.../elf/tst-ro-dynamic-mod.so'

This updates BZ #28340 fix.

(cherry picked from commit 15e6d6785a)
2021-11-03 10:21:04 +01:00
H.J. Lu
f42373f911 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>
(cherry picked from commit b413280cfb)
2021-11-03 07:50:30 +01:00
Adhemerval Zanella
3908fa933a elf: Fix audit regression
Commit 03e187a41d added a regression when an audit module does not have
libc as DT_NEEDED (although unusual it is possible).

Checked on x86_64-linux-gnu.
2021-07-30 16:01:44 -03:00
Siddhesh Poyarekar
2d2d9f2b48 Move malloc hooks into a compat DSO
Remove all malloc hook uses from core malloc functions and move it
into a new library libc_malloc_debug.so.  With this, the hooks now no
longer have any effect on the core library.

libc_malloc_debug.so is a malloc interposer that needs to be preloaded
to get hooks functionality back so that the debugging features that
depend on the hooks, i.e. malloc-check, mcheck and mtrace work again.
Without the preloaded DSO these debugging features will be nops.
These features will be ported away from hooks in subsequent patches.

Similarly, legacy applications that need hooks functionality need to
preload libc_malloc_debug.so.

The symbols exported by libc_malloc_debug.so are maintained at exactly
the same version as libc.so.

Finally, static binaries will no longer be able to use malloc
debugging features since they cannot preload the debugging DSO.

Reviewed-by: Carlos O'Donell <carlos@redhat.com>
Tested-by: Carlos O'Donell <carlos@redhat.com>
2021-07-22 18:37:59 +05:30
Adhemerval Zanella
3a0253ac6f elf: Add -Wl,--no-as-needed for tst-tls-manydynamic*mod-dep-bad.so (BZ #28089)
The tests explicit requires the dependencies and it is required for
the case the toolchain defaults to -Wl,--as-needed.

Checked on x86_64-linux-gnu.
2021-07-15 08:18:21 -03:00
Adhemerval Zanella
ba33937be2 elf: Fix DTV gap reuse logic (BZ #27135)
This is updated version of the 572bd547d5 (reverted by 40ebfd016a)
that fixes the _dl_next_tls_modid issues.

This issue with 572bd547d5 patch is the DTV entry will be only
update on dl_open_worker() with the update_tls_slotinfo() call after
all dependencies are being processed by _dl_map_object_deps().  However
_dl_map_object_deps() itself might call _dl_next_tls_modid(), and since
the _dl_tls_dtv_slotinfo_list::map is not yet set the entry will be
wrongly reused.

This patch fixes by renaming the _dl_next_tls_modid() function to
_dl_assign_tls_modid() and by passing the link_map so it can set
the slotinfo value so a subsequente _dl_next_tls_modid() call will
see the entry as allocated.

The intermediary value is cleared up on remove_slotinfo() for the case
a library fails to load with RTLD_NOW.

This patch fixes BZ #27135.

Checked on x86_64-linux-gnu.

Reviewed-by: Szabolcs Nagy <szabolcs.nagy@arm.com>
2021-07-14 15:10:27 -03:00
Siddhesh Poyarekar
5ceb1630bd elf/tests: Make thrlock and noload depend on libm
Both tests try to dlopen libm.so at runtime, so make them depend on it
so that they're executed if libm.so has been updated.

Reviewed-by: Florian Weimer <fweimer@redhat.com>
2021-07-08 13:39:19 +05:30
Florian Weimer
7a5db2e82f elf: Clean up GLIBC_PRIVATE exports of internal libdl symbols
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>
2021-07-07 08:41:24 +02:00
Florian Weimer
30639e79d3 Linux: Cleanups after librt move
librt.so is no longer installed for PTHREAD_IN_LIBC, and tests
are not linked against it.  $(librt) is introduced globally for
shared tests that need to be linked for both PTHREAD_IN_LIBC
and !PTHREAD_IN_LIBC.

GLIBC_PRIVATE symbols that were needed during the transition are
removed again.

Reviewed-by: Carlos O'Donell <carlos@redhat.com>
2021-06-28 09:51:01 +02:00
Florian Weimer
8208be389b Install shared objects under their ABI names
Previously, the installed objects were named like libc-2.33.so,
and the ABI soname libc.so.6 was just a symbolic link.

The Makefile targets to install these symbolic links are no longer
needed after this, so they are removed with this commit.  The more
general $(make-link) command (which invokes scripts/rellns-sh) is
retained because other symbolic links are still needed.

Reviewed-by: Carlos O'Donell <carlos@redhat.com>
Tested-by: Carlos O'Donell <carlos@rehdat.com>
2021-06-28 08:33:57 +02:00
Florian Weimer
6bf789d69e elf: Generalize name-based DSO recognition in ldconfig
This introduces <dl-is_dso.h> and the _dl_is_dso function.  A
test ensures that the official names of libc.so, ld.so, and their
versioned names are recognized.

Reviewed-by: Carlos O'Donell <carlos@redhat.com>
Tested-by: Carlos O'Donell <carlos@redhat.com>
2021-06-28 08:33:57 +02:00
Florian Weimer
c2059edce2 elf: Use _dl_catch_error from base namespace in dl-libc.c [BZ #27646]
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>
2021-06-17 15:06:46 +02:00
Florian Weimer
699361795f Remove stale references to libdl.a
Since commit 0c1c3a771e
("dlfcn: Move dlopen into libc") libdl.a is empty, so linking
against it is no longer necessary.

Reviewed-by: Adhemerval Zanella  <adhemerval.zanella@linaro.org>
2021-06-09 19:14:02 +02:00
Stefan Liebler
51a3df5e35 Fix elf/tst-tls9-static after libdl cleanups.
The testcase elf/tst-tls9-static sometimes fails with:
cannot open 'tst-tlsmod5.so': tst-tlsmod5.so: cannot open shared object file: No such file or directory
cannot open 'tst-tlsmod6.so': tst-tlsmod6.so: cannot open shared object file: No such file or directory

After recent commit
6f1c701026
"dlfcn: Cleanups after -ldl is no longer required"
the libdl variable is not set anymore and thus the
dependencies were missing.
2021-06-09 13:38:41 +02:00
Florian Weimer
6f1c701026 dlfcn: Cleanups after -ldl is no longer required
This commit removes the ELF constructor and internal variables from
dlfcn/dlfcn.c.  The file now serves the same purpose as
nptl/libpthread-compat.c, so it is renamed to dlfcn/libdl-compat.c.
The use of libdl-shared-only-routines ensures that libdl.a is empty.

This commit adjusts the test suite not to use $(libdl).  The libdl.so
symbolic link is no longer installed.

Reviewed-by: Adhemerval Zanella  <adhemerval.zanella@linaro.org>
2021-06-03 09:11:45 +02:00
Florian Weimer
77f876c0e3 dlfcn: Move dlsym into libc
The symbol was moved using scripts/move-symbol-to-libc.py.

In elf/Makefile, remove the $(libdl) dependency from testobj1.so
because it the unused libdl DSO now causes elf/tst-unused-deps to
fail.

Reviewed-by: Adhemerval Zanella  <adhemerval.zanella@linaro.org>
2021-06-03 08:26:04 +02:00
Florian Weimer
7862ff8e69 elf: Use custom NODELETE DSO for tst-dlopenfail, tst-dlopenfail-2
Once libpthread is empty and no longer marked NODELETE, it no longer
can be used for testing.

Reviewed-by: Adhemerval Zanella  <adhemerval.zanella@linaro.org>
2021-05-21 22:35:00 +02:00
Florian Weimer
78b31cc834 elf: Partially initialize ld.so after static dlopen (bug 20802)
After static dlopen, a copy of ld.so is loaded into the inner
namespace, but that copy is not initialized at all.  Some
architectures run into serious problems as result, which is why the
_dl_var_init mechanism was invented.  With libpthread moving into
libc and parts into ld.so, more architectures impacted, so it makes
sense to switch to a generic mechanism which performs the partial
initialization.

As a result, getauxval now works after static dlopen (bug 20802).

Reviewed-by: Adhemerval Zanella  <adhemerval.zanella@linaro.org>
2021-05-17 10:06:57 +02:00
Romain GEISSLER
5188a9d026 Remove all usage of @BASH@ or ${BASH} in installed files, and hardcode /bin/bash instead
(FYI, this is a repost of
https://sourceware.org/pipermail/libc-alpha/2019-July/105035.html now
that FSF papers have been signed and confirmed on FSF side).

This trivial patch attemps to fix BZ 24106. Basically the bash locally
used when building glibc on the host shall not leak on the installed
glibc, as the system where it is installed might be different and use
another bash location.

So I have looked for all occurences of @BASH@ or $(BASH) in installed
files, and replaced it by /bin/bash. This was suggested by Florian
Weimer in the bug report.

Reviewed-by: Siddhesh Poyarekar <siddhesh@sourceware.org>
2021-05-12 07:47:11 +05:30
Szabolcs Nagy
9d0e30329c elf: Add test case for [BZ #19329]
Test concurrent dlopen and pthread_create when the loaded modules have
TLS.  This triggers dl-tls assertion failures more reliably than the
nptl/tst-stack4 test.

The dlopened module has 100 DT_NEEDED dependencies with TLS, they were
reused from an existing TLS test. The number of created threads during
dlopen depends on filesystem speed and hardware, but at most 3 threads
are alive at a time to limit resource usage.

Reviewed-by: Adhemerval Zanella  <adhemerval.zanella@linaro.org>
2021-05-11 17:16:37 +01:00
Florian Weimer
d6163dfd38 elf, nptl: Resolve recursive lock implementation early
If libpthread is included in libc, it is not necessary to delay
initialization of the lock/unlock function pointers until libpthread
is loaded.  This eliminates two unprotected function pointers
from _rtld_global and removes some initialization code from
libpthread.

Tested-by: Carlos O'Donell <carlos@redhat.com>
Reviewed-by: Carlos O'Donell <carlos@redhat.com>
2021-05-10 10:31:41 +02:00
Florian Weimer
ce0b7961ae nptl: Consolidate async cancel enable/disable implementation in libc
Previously, the source file nptl/cancellation.c was compiled multiple
times, for libc, libpthread, librt.  This commit switches to a single
implementation, with new __pthread_enable_asynccancel@@GLIBC_PRIVATE,
__pthread_disable_asynccancel@@GLIBC_PRIVATE exports.

The almost-unused CANCEL_ASYNC and CANCEL_RESET macros are replaced
by LIBC_CANCEL_ASYNC and LIBC_CANCEL_ASYNC macros.  They call the
__pthread_* functions unconditionally now.  The macros are still
needed because shared code uses them; Hurd has different definitions.

Reviewed-by: Adhemerval Zanella  <adhemerval.zanella@linaro.org>
2021-05-05 17:19:32 +02:00
Florian Weimer
90d7e7e5bd elf: Introduce __tls_init_tp for second-phase TCB initialization
TLS_INIT_TP is processor-specific, so it is not a good place to
put thread library initialization code (it would have to be repeated
for all CPUs).  Introduce __tls_init_tp as a separate function,
to be called immediately after TLS_INIT_TP.  Move the existing
stack list setup code for NPTL to this function.

Reviewed-by: Adhemerval Zanella  <adhemerval.zanella@linaro.org>
2021-04-21 19:49:51 +02:00
Florian Weimer
b2964eb1d9 dlfcn: Failures after dlmopen should not terminate process [BZ #24772]
Commit 9e78f6f6e7 ("Implement
_dl_catch_error, _dl_signal_error in libc.so [BZ #16628]") has the
side effect that distinct namespaces, as created by dlmopen, now have
separate implementations of the rtld exception mechanism.  This means
that the call to _dl_catch_error from libdl in a secondary namespace
does not actually install an exception handler because the
thread-local variable catch_hook in the libc.so copy in the secondary
namespace is distinct from that of the base namepace.  As a result, a
dlsym/dlopen/... failure in a secondary namespace terminates the process
with a dynamic linker error because it looks to the exception handler
mechanism as if no handler has been installed.

This commit restores GLRO (dl_catch_error) and uses it to set the
handler in the base namespace.

Reviewed-by: Adhemerval Zanella  <adhemerval.zanella@linaro.org>
2021-04-21 19:49:51 +02:00
Florian Weimer
1d95b035c7 nptl: Move __pthread_unwind_next into libc
It's necessary to stub out __libc_disable_asynccancel and
__libc_enable_asynccancel via rtld-stubbed-symbols because the new
direct references to the unwinder result in symbol conflicts when the
rtld exception handling from libc is linked in during the construction
of librtld.map.

unwind-forcedunwind.c is merged into unwind-resume.c.  libc now needs
the functions that were previously only used in libpthread.

The GLIBC_PRIVATE exports of __libc_longjmp and __libc_siglongjmp are
no longer needed, so switch them to hidden symbols.

The symbol __pthread_unwind_next has been moved using
scripts/move-symbol-to-libc.py.

Reviewed-by: Adhemerva Zanella  <adhemerval.zanella@linaro.org>
2021-04-21 19:49:50 +02:00
Szabolcs Nagy
8f85075a2e elf: Add a DTV setup test [BZ #27136]
The test dlopens a large number of modules with TLS, they are reused
from an existing test.

The test relies on the reuse of slotinfo entries after dlclose, without
bug 27135 fixed this needs a failing dlopen. With a slotinfo list that
has non-monotone increasing generation counters, bug 27136 can trigger.

Reviewed-by: Adhemerval Zanella  <adhemerval.zanella@linaro.org>
2021-04-15 09:30:43 +01:00
Siddhesh Poyarekar
061fe3f8ad Enhance setuid-tunables test
Instead of passing GLIBC_TUNABLES via the environment, pass the
environment variable from parent to child.  This allows us to test
multiple variables to ensure better coverage.

The test list currently only includes the case that's already being
tested.  More tests will be added later.
Reviewed-by: Carlos O'Donell <carlos@redhat.com>
2021-04-12 19:03:19 +05:30