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2021-09-16elf: Remove THREAD_GSCOPE_IN_TCBSergey Bugaev
All the ports now have THREAD_GSCOPE_IN_TCB set to 1. Remove all support for !THREAD_GSCOPE_IN_TCB, along with the definition itself. Signed-off-by: Sergey Bugaev <bugaevc@gmail.com> Message-Id: <20210915171110.226187-4-bugaevc@gmail.com> Reviewed-by: Samuel Thibault <samuel.thibault@ens-lyon.org>
2021-09-15elf: Replace most uses of THREAD_GSCOPE_IN_TCBSergey Bugaev
While originally this definition was indeed used to distinguish between the cases where the GSCOPE flag was stored in TCB or not, it has since become used as a general way to distinguish between HTL and NPTL. THREAD_GSCOPE_IN_TCB will be removed in the following commits, as HTL, which currently is the only port that does not put the flag into TCB, will get ported to put the GSCOPE flag into the TCB as well. To prepare for that change, migrate all code that wants to distinguish between HTL and NPTL to use PTHREAD_IN_LIBC instead, which is a better choice since the distinction mostly has to do with whether libc has access to the list of thread structures and therefore can initialize thread-local storage. The parts of code that actually depend on whether the GSCOPE flag is in TCB are left unchanged. Signed-off-by: Sergey Bugaev <bugaevc@gmail.com> Message-Id: <20210907133325.255690-2-bugaevc@gmail.com> Reviewed-by: Samuel Thibault <samuel.thibault@ens-lyon.org>
2021-09-03Remove "Contributed by" linesSiddhesh Poyarekar
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/b5ecac94eabfd72ed2916d6d8157e7dc https://gist.github.com/siddhesh/15ea1f5e435ace9774f485030695ee02 Reviewed-by: Carlos O'Donell <carlos@redhat.com>
2021-08-24elf: Skip tst-auditlogmod-* if the linker doesn't support --depaudit [BZ #28151]Fangrui Song
gold and ld.lld do not support --audit or --depaudit. Reviewed-by: Adhemerval Zanella <adhemerval.zanella@linaro.org>
2021-08-23rtld: copy terminating null in tunables_strdup (bug 28256)Andreas Schwab
Avoid triggering a false positive from valgrind by copying the terminating null in tunables_strdup. At this point the heap is still clean, but valgrind is stricter here.
2021-08-20elf: Fix missing colon in LD_SHOW_AUXV output [BZ #28253]Arjun Shankar
This commit adds a missing colon in the AT_MINSIGSTKSZ entry in the _dl_show_auxv function.
2021-08-16elf: Drop elf/tls-macros.h in favor of __thread and tls_model attributes [BZ ↵Fangrui Song
#28152] [BZ #28205] elf/tls-macros.h was added for TLS testing when GCC did not support __thread. __thread and tls_model attributes are mature now and have been used by many newer tests. Also delete tst-tls2.c which tests .tls_common (unused by modern GCC and unsupported by Clang/LLD). .tls_common and .tbss definition are almost identical after linking, so the runtime test doesn't add additional coverage. Assembler and linker tests should be on the binutils side. When LLD 13.0.0 is allowed in configure.ac (https://sourceware.org/pipermail/libc-alpha/2021-August/129866.html), `make check` result is on par with glibc built with GNU ld on aarch64 and x86_64. As a future clean-up, TLS_GD/TLS_LD/TLS_IE/TLS_IE macros can be removed from sysdeps/*/tls-macros.h. We can add optional -mtls-dialect={gnu2,trad} tests to ensure coverage. Tested on aarch64-linux-gnu, powerpc64le-linux-gnu, and x86_64-linux-gnu. Reviewed-by: Szabolcs Nagy <szabolcs.nagy@arm.com>
2021-08-10elf: Unconditionally use __ehdr_startFangrui Song
We can consider __ehdr_start (from binutils 2.23 onwards) unconditionally supported, since configure.ac requires binutils>=2.25. The configure.ac check is related to an ia64 bug fixed by binutils 2.24. See https://sourceware.org/pipermail/libc-alpha/2014-August/053503.html Tested on x86_64-linux-gnu. Tested build-many-glibcs.py with aarch64-linux-gnu and s390x-linux-gnu. Reviewed-by: Szabolcs Nagy <szabolcs.nagy@arm.com>
2021-08-03ldconfig: avoid leak on empty paths in config fileSiddhesh Poyarekar
Reviewed-by: Arjun Shankar <arjun@redhat.com>
2021-07-30elf: Fix audit regressionAdhemerval Zanella
Commit 03e187a41d9 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.
2021-07-22Move malloc hooks into a compat DSOSiddhesh Poyarekar
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>
2021-07-16elf: Fix a wrong array access on tst-tls20Adhemerval Zanella
Check on x86_64-linux-gnu with --enable-stack-protector=all.
2021-07-15elf: Add -Wl,--no-as-needed for tst-tls-manydynamic*mod-dep-bad.so (BZ #28089)Adhemerval Zanella
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.
2021-07-14elf: Fix DTV gap reuse logic (BZ #27135)Adhemerval Zanella
This is updated version of the 572bd547d57a (reverted by 40ebfd016ad2) that fixes the _dl_next_tls_modid issues. This issue with 572bd547d57a 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>
2021-07-09Force building with -fno-commonFlorian Weimer
As a result, is not necessary to specify __attribute__ ((nocommon)) on individual definitions. GCC 10 defaults to -fno-common on all architectures except ARC, but this change is compatible with older GCC versions and ARC, too. Reviewed-by: Carlos O'Donell <carlos@redhat.com>
2021-07-08Add NT_ARM_PAC_ENABLED_KEYS to elf.hJoseph Myers
This patch adds the new NT_ARM_PAC_ENABLED_KEYS constant from Linux 5.13 to glibc's elf.h. Tested for x86_64.
2021-07-08elf/tests: Make thrlock and noload depend on libmSiddhesh Poyarekar
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>
2021-07-07elf: Clean up GLIBC_PRIVATE exports of internal libdl symbolsFlorian Weimer
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>
2021-07-06elf: Call free from base namespace on error in dl-libc.c [BZ #27646]Florian Weimer
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 c2059edce20c124d1a99f1a94cc52e83b77a917a ("elf: Use _dl_catch_error from base namespace in dl-libc.c [BZ #27646]") and commit b2964eb1d9a6b8ab1250e8a881cf406182da5875 ("dlfcn: Failures after dlmopen should not terminate process [BZ #24772]").
2021-06-28Linux: Cleanups after librt moveFlorian Weimer
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>
2021-06-28Install shared objects under their ABI namesFlorian Weimer
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>
2021-06-28elf: Generalize name-based DSO recognition in ldconfigFlorian Weimer
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>
2021-06-25elf: Disable most of TLS modid gaps processing [BZ #27135]Florian Weimer
Revert "elf: Fix DTV gap reuse logic [BZ #27135]" This reverts commit 572bd547d57a39b6cf0ea072545dc4048921f4c3. It turns out that the _dl_next_tls_modid in _dl_map_object_from_fd keeps returning the same modid over and over again if there is a gap and more than TLS-using module is loaded in one dlopen call. This corrupts TLS data structures. The bug is still present after a revert, but empirically it is much more difficult to trigger (because it involves a dlopen failure).
2021-06-25elf: Fix glibc-hwcaps priorities with cache flags mismatches [BZ #27046]Florian Weimer
If lib->flags (in the cache) did not match GLRO (dl_correct_cache_id), searching for further glibc-hwcaps entries did not happen, and it was possible that the best glibc-hwcaps was not found. By accident, this causes a test failure for elf/tst-glibc-hwcaps-prepend-cache on armv7l. This commit changes the cache lookup logic to continue searching if (a) no match has been found, (b) a named glibc-hwcaps match has been found(), or (c) non-glibc-hwcaps match has been found and the entry flags and cache default flags do not match. _DL_CACHE_DEFAULT_ID is used instead of GLRO (dl_correct_cache_id) because the latter is only written once on i386 if loading of libc.so.5 libraries is selected, so GLRO (dl_correct_cache_id) should probably removed in a future change. Reviewed-by: Szabolcs Nagy <szabolcs.nagy@arm.com>
2021-06-22Use 64 bit time_t stat internallyAdhemerval Zanella
For the legacy ABI with supports 32-bit time_t it calls the 64-bit time directly, since the LFS symbols calls the 64-bit time_t ones internally. Checked on i686-linux-gnu and x86_64-linux-gnu. Reviewed-by: Lukasz Majewski <lukma@denx.de>
2021-06-17elf: Use _dl_catch_error from base namespace in dl-libc.c [BZ #27646]Florian Weimer
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 b2964eb1d9a6b8ab1250e8a881cf406182da5875 ("dlfcn: Failures after dlmopen should not terminate process [BZ #24772]"). Reviewed-by: Siddhesh Poyarekar <siddhesh@sourceware.org>
2021-06-09Remove stale references to libdl.aFlorian Weimer
Since commit 0c1c3a771eceec46e66ce1183cf988e2303bd373 ("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>
2021-06-09Fix elf/tst-tls9-static after libdl cleanups.Stefan Liebler
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 6f1c701026287f6928d3bdd1aea7359308635abe "dlfcn: Cleanups after -ldl is no longer required" the libdl variable is not set anymore and thus the dependencies were missing.
2021-06-03dlfcn: Rework static dlopen hooksFlorian Weimer
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>
2021-06-03dlfcn: Cleanups after -ldl is no longer requiredFlorian Weimer
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>
2021-06-03dlfcn: Move dlvsym into libcFlorian Weimer
The symbol was moved using scripts/move-symbol-to-libc.py. Reviewed-by: Adhemerval Zanella <adhemerval.zanella@linaro.org>
2021-06-03dlfcn: Move dlsym into libcFlorian Weimer
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>
2021-05-21elf: Use custom NODELETE DSO for tst-dlopenfail, tst-dlopenfail-2Florian Weimer
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>
2021-05-21nptl: Eliminate the __static_tls_size, __static_tls_align_m1 variablesFlorian Weimer
Use the __nptl_tls_static_size_for_stack inline function instead, and the GLRO (dl_tls_static_align) value directly. The computation of GLRO (dl_tls_static_align) in _dl_determine_tlsoffset ensures that the alignment is at least TLS_TCB_ALIGN, which at least STACK_ALIGN (see allocate_stack). Therefore, the additional rounding-up step is removed. ALso move the initialization of the default stack size from __pthread_initialize_minimal_internal to __pthread_early_init. This introduces an extra system call during single-threaded startup, but this simplifies the initialization sequence. No locking is needed around the writes to __default_pthread_attr because the process is single-threaded at this point. Reviewed-by: Adhemerval Zanella <adhemerval.zanella@linaro.org>
2021-05-20elf: Initialize GLRO (dl_minsigstacksize) after static dlopenFlorian Weimer
This is another field of _rtld_global_ro that benefits from initialization in __rtld_static_init. Reviewed-by: H.J. Lu <hjl.tools@gmail.com>
2021-05-19elf: Add hook for checking HWCAP bits after auxiliary vector parsingFlorian Weimer
Reviewed-by: Stefan Liebler <stli@linux.ibm.com>
2021-05-18ldconfig: Avoid boolean coercion of opt_chrootSiddhesh Poyarekar
Generated code is unchanged.
2021-05-18ldconfig: Fix memory leaksSiddhesh Poyarekar
Coverity discovered that paths allocated by chroot_canon are not freed in a couple of routines in ldconfig. Reviewed-by: Adhemerval Zanella <adhemerval.zanella@linaro.org>
2021-05-18elf/cache.c: Fix resource leaks identified by static analyzersSiddhesh Poyarekar
A coverity run identified a number of resource leaks in cache.c. There are a couple of simple memory leaks where a local allocation is not freed before function return. Then there is a mmap leak and a file descriptor leak where a map is not unmapped in the error case and a file descriptor remains open respectively. Reviewed-by: Adhemerval Zanella <adhemerval.zanella@linaro.org>
2021-05-17elf: Move static TLS size and alignment into _rtld_global_roFlorian Weimer
This helps to clarify that the caching of these fields in libpthread (in __static_tls_size, __static_tls_align_m1) is unnecessary. Reviewed-by: Adhemerval Zanella <adhemerval.zanella@linaro.org>
2021-05-17elf: Remove DL_STATIC_INITFlorian Weimer
All users have been converted to the __rtld_static_init mechanism. Reviewed-by: Adhemerval Zanella <adhemerval.zanella@linaro.org>
2021-05-17elf: Partially initialize ld.so after static dlopen (bug 20802)Florian Weimer
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>
2021-05-12Remove all usage of @BASH@ or ${BASH} in installed files, and hardcode ↵Romain GEISSLER
/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>
2021-05-11elf: Fix DTV gap reuse logic [BZ #27135]Szabolcs Nagy
For some reason only dlopen failure caused dtv gaps to be reused. It is possible that the intent was to never reuse modids for a different module, but after dlopen failure all gaps are reused not just the ones caused by the unfinished dlopened. So the code has to handle reused modids already which seems to work, however the data races at thread creation and tls access (see bug 19329 and bug 27111) may be more severe if slots are reused so this is scheduled after those fixes. I think fixing the races are not simpler if reuse is disallowed and reuse has other benefits, so set GL(dl_tls_dtv_gaps) whenever entries are removed from the middle of the slotinfo list. The value does not have to be correct: incorrect true value causes the next modid query to do a slotinfo walk, incorrect false will leave gaps and new entries are added at the end. Fixes bug 27135. Reviewed-by: Adhemerval Zanella <adhemerval.zanella@linaro.org>
2021-05-11elf: Add test case for [BZ #19329]Szabolcs Nagy
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>
2021-05-11elf: Use relaxed atomics for racy accesses [BZ #19329]Szabolcs Nagy
This is a follow up patch to the fix for bug 19329. This adds relaxed MO atomics to accesses that were previously data races but are now race conditions, and where relaxed MO is sufficient. The race conditions all follow the pattern that the write is behind the dlopen lock, but a read can happen concurrently (e.g. during tls access) without holding the lock. For slotinfo entries the read value only matters if it reads from a synchronized write in dlopen or dlclose, otherwise the related dtv entry is not valid to access so it is fine to leave it in an inconsistent state. The same applies for GL(dl_tls_max_dtv_idx) and GL(dl_tls_generation), but there the algorithm relies on the fact that the read of the last synchronized write is an increasing value. Reviewed-by: Adhemerval Zanella <adhemerval.zanella@linaro.org>
2021-05-11elf: Fix data races in pthread_create and TLS access [BZ #19329]Szabolcs Nagy
DTV setup at thread creation (_dl_allocate_tls_init) is changed to take the dlopen lock, GL(dl_load_lock). Avoiding data races here without locks would require design changes: the map that is accessed for static TLS initialization here may be concurrently freed by dlclose. That use after free may be solved by only locking around static TLS setup or by ensuring dlclose does not free modules with static TLS, however currently every link map with TLS has to be accessed at least to see if it needs static TLS. And even if that's solved, still a lot of atomics would be needed to synchronize DTV related globals without a lock. So fix both bug 19329 and bug 27111 with a lock that prevents DTV setup running concurrently with dlopen or dlclose. _dl_update_slotinfo at TLS access still does not use any locks so CONCURRENCY NOTES are added to explain the synchronization. The early exit from the slotinfo walk when max_modid is reached is not strictly necessary, but does not hurt either. An incorrect acquire load was removed from _dl_resize_dtv: it did not synchronize with any release store or fence and synchronization is now handled separately at thread creation and TLS access time. There are still a number of racy read accesses to globals that will be changed to relaxed MO atomics in a followup patch. This should not introduce regressions compared to existing behaviour and avoid cluttering the main part of the fix. Not all TLS access related data races got fixed here: there are additional races at lazy tlsdesc relocations see bug 27137. Reviewed-by: Adhemerval Zanella <adhemerval.zanella@linaro.org>
2021-05-11_dl_exception_create_format: Add missing va_endSiddhesh Poyarekar
Coverity discovered a missing va_end.
2021-05-10nptl: Move changing of stack permissions into ld.soFlorian Weimer
All the stack lists are now in _rtld_global, so it is possible to change stack permissions directly from there, instead of calling into libpthread to do the change. Tested-by: Carlos O'Donell <carlos@redhat.com> Reviewed-by: Carlos O'Donell <carlos@redhat.com>
2021-05-10nptl: Move more stack management variables into _rtld_globalFlorian Weimer
Permissions of the cached stacks may have to be updated if an object is loaded that requires executable stacks, so the dynamic loader needs to know about these cached stacks. The move of in_flight_stack and stack_cache_actsize is a requirement for merging __reclaim_stacks into the fork implementation in libc. Tested-by: Carlos O'Donell <carlos@redhat.com> Reviewed-by: Carlos O'Donell <carlos@redhat.com>