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* elf: Fix initial-exec TLS access on audit modules (BZ #28096)Adhemerval Zanella2022-02-011-3/+14
| | | | | | | | | | | | | | | | | 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>
* Update copyright dates with scripts/update-copyrightsPaul Eggert2022-01-011-1/+1
| | | | | | | | | | | | | | | | | | | | | | | 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
* Remove TLS_TCB_ALIGN and TLS_INIT_TCB_ALIGNFlorian Weimer2021-12-091-2/+2
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | TLS_INIT_TCB_ALIGN is not actually used. TLS_TCB_ALIGN was likely introduced to support a configuration where the thread pointer has not the same alignment as THREAD_SELF. Only ia64 seems to use that, but for the stack/pointer guard, not for storing tcbhead_t. Some ports use TLS_TCB_OFFSET and TLS_PRE_TCB_SIZE to shift the thread pointer, potentially landing in a different residue class modulo the alignment, but the changes should not impact that. In general, given that TLS variables have their own alignment requirements, having different alignment for the (unshifted) thread pointer and struct pthread would potentially result in dynamic offsets, leading to more complexity. hppa had different values before: __alignof__ (tcbhead_t), which seems to be 4, and __alignof__ (struct pthread), which was 8 (old default) and is now 32. However, it defines THREAD_SELF as: /* Return the thread descriptor for the current thread. */ # define THREAD_SELF \ ({ struct pthread *__self; \ __self = __get_cr27(); \ __self - 1; \ }) So the thread pointer points after struct pthread (hence __self - 1), and they have to have the same alignment on hppa as well. Similarly, on ia64, the definitions were different. We have: # define TLS_PRE_TCB_SIZE \ (sizeof (struct pthread) \ + (PTHREAD_STRUCT_END_PADDING < 2 * sizeof (uintptr_t) \ ? ((2 * sizeof (uintptr_t) + __alignof__ (struct pthread) - 1) \ & ~(__alignof__ (struct pthread) - 1)) \ : 0)) # define THREAD_SELF \ ((struct pthread *) ((char *) __thread_self - TLS_PRE_TCB_SIZE)) And TLS_PRE_TCB_SIZE is a multiple of the struct pthread alignment (confirmed by the new _Static_assert in sysdeps/ia64/libc-tls.c). On m68k, we have a larger gap between tcbhead_t and struct pthread. But as far as I can tell, the port is fine with that. The definition of TCB_OFFSET is sufficient to handle the shifted TCB scenario. This fixes commit 23c77f60181eb549f11ec2f913b4270af29eee38 ("nptl: Increase default TCB alignment to 32"). Reviewed-by: H.J. Lu <hjl.tools@gmail.com>
* elf: Avoid deadlock between pthread_create and ctors [BZ #28357]Szabolcs Nagy2021-10-041-8/+8
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | The fix for bug 19329 caused a regression such that pthread_create can deadlock when concurrent ctors from dlopen are waiting for it to finish. Use a new GL(dl_load_tls_lock) in pthread_create that is not taken around ctors in dlopen. The new lock is also used in __tls_get_addr instead of GL(dl_load_lock). The new lock is held in _dl_open_worker and _dl_close_worker around most of the logic before/after the init/fini routines. When init/fini routines are running then TLS is in a consistent, usable state. In _dl_open_worker the new lock requires catching and reraising dlopen failures that happen in the critical section. The new lock is reinitialized in a fork child, to keep the existing behaviour and it is kept recursive in case malloc interposition or TLS access from signal handlers can retake it. It is not obvious if this is necessary or helps, but avoids changing the preexisting behaviour. The new lock may be more appropriate for dl_iterate_phdr too than GL(dl_load_write_lock), since TLS state of an incompletely loaded module may be accessed. If the new lock can replace the old one, that can be a separate change. Fixes bug 28357. Reviewed-by: Adhemerval Zanella <adhemerval.zanella@linaro.org>
* elf: Replace most uses of THREAD_GSCOPE_IN_TCBSergey Bugaev2021-09-151-3/+3
| | | | | | | | | | | | | | | | | | | | | | 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>
* elf: Fix DTV gap reuse logic (BZ #27135)Adhemerval Zanella2021-07-141-8/+9
| | | | | | | | | | | | | | | | | | | | | | | | | | 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>
* elf: Disable most of TLS modid gaps processing [BZ #27135]Florian Weimer2021-06-251-1/+4
| | | | | | | | | | | | | 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).
* nptl: Eliminate the __static_tls_size, __static_tls_align_m1 variablesFlorian Weimer2021-05-211-2/+3
| | | | | | | | | | | | | | | | | | | 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>
* elf: Move static TLS size and alignment into _rtld_global_roFlorian Weimer2021-05-171-11/+11
| | | | | | | 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>
* elf: Fix DTV gap reuse logic [BZ #27135]Szabolcs Nagy2021-05-111-4/+1
| | | | | | | | | | | | | | | | | | | | | | | 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>
* elf: Use relaxed atomics for racy accesses [BZ #19329]Szabolcs Nagy2021-05-111-8/+23
| | | | | | | | | | | | | | | | | | 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>
* elf: Fix data races in pthread_create and TLS access [BZ #19329]Szabolcs Nagy2021-05-111-16/+47
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 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>
* elf, nptl: Initialize static TLS directly in ld.soFlorian Weimer2021-05-051-0/+39
| | | | | | | | | | The stack list is available in ld.so since commit 1daccf403b1bd86370eb94edca794dc106d02039 ("nptl: Move stack list variables into _rtld_global"), so it's possible to walk the stack list directly in ld.so and perform the initialization there. This eliminates an unprotected function pointer from _rtld_global and reduces the libpthread initialization code.
* elf: Refactor _dl_update_slotinfo to avoid use after freeSzabolcs Nagy2021-04-151-16/+5
| | | | | | | | | | | | map is not valid to access here because it can be freed by a concurrent dlclose: during tls access (via __tls_get_addr) _dl_update_slotinfo is called without holding dlopen locks. So don't check the modid of map. The map == 0 and map != 0 code paths can be shared (avoiding the dtv resize in case of map == 0 is just an optimization: larger dtv than necessary would be fine too). Reviewed-by: Adhemerval Zanella <adhemerval.zanella@linaro.org>
* elf: Fix comments and logic in _dl_add_to_slotinfoSzabolcs Nagy2021-04-151-10/+1
| | | | | | | | | | | | | | | Since commit a509eb117fac1d764b15eba64993f4bdb63d7f3c Avoid late dlopen failure due to scope, TLS slotinfo updates [BZ #25112] the generation counter update is not needed in the failure path. That commit ensures allocation in _dl_add_to_slotinfo happens before the demarcation point in dlopen (it is called twice, first time is for allocation only where dlopen can still be reverted on failure, then second time actual dtv updates are done which then cannot fail). Reviewed-by: Adhemerval Zanella <adhemerval.zanella@linaro.org>
* elf: Fix a DTV setup issue [BZ #27136]Szabolcs Nagy2021-04-151-1/+1
| | | | | | | | | | | The max modid is a valid index in the dtv, it should not be skipped. The bug is observable if the last module has modid == 64 and its generation is same or less than the max generation of the previous modules. Then dtv[0].counter implies dtv[64] is initialized but it isn't. Fixes bug 27136. Reviewed-by: Adhemerval Zanella <adhemerval.zanella@linaro.org>
* Update copyright dates with scripts/update-copyrightsPaul Eggert2021-01-021-1/+1
| | | | | | | | | | | | | | | | 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
* elf: Change TLS static surplus default back to 1664Florian Weimer2020-07-201-7/+30
| | | | | | | Make the computation in elf/dl-tls.c more transparent, and add an explicit test for the historic value. Reviewed-by: Carlos O'Donell <carlos@redhat.com>
* Linux: Remove rseq supportFlorian Weimer2020-07-161-7/+1
| | | | | | | | | | | | | | | | | | The kernel ABI is not finalized, and there are now various proposals to change the size of struct rseq, which would make the glibc ABI dependent on the version of the kernels used for building glibc. This is of course not acceptable. This reverts commit 48699da1c468543ade14777819bd1b4d652709de ("elf: Support at least 32-byte alignment in static dlopen"), commit 8f4632deb3545b2949cec5454afc3cb21a0024ea ("Linux: rseq registration tests"), commit 6e29cb3f61ff5432c78a1c84b0d9b123a350ab36 ("Linux: Use rseq in sched_getcpu if available"), and commit 0c76fc3c2b346dc5401dc055d97d4279632b0fb3 ("Linux: Perform rseq registration at C startup and thread creation"), resolving the conflicts introduced by the ARC port and the TLS static surplus changes. Reviewed-by: Carlos O'Donell <carlos@redhat.com>
* rtld: Avoid using up static TLS surplus for optimizations [BZ #25051]Szabolcs Nagy2020-07-081-4/+5
| | | | | | | | | | | | | | | | | | | | | | | | | | | | On some targets static TLS surplus area can be used opportunistically for dynamically loaded modules such that the TLS access then becomes faster (TLSDESC and powerpc TLS optimization). However we don't want all surplus TLS to be used for this optimization because dynamically loaded modules with initial-exec model TLS can only use surplus TLS. The new contract for surplus static TLS use is: - libc.so can have up to 192 bytes of IE TLS, - other system libraries together can have up to 144 bytes of IE TLS. - Some "optional" static TLS is available for opportunistic use. The optional TLS is now tunable: rtld.optional_static_tls, so users can directly affect the allocated static TLS size. (Note that module unloading with dlclose does not reclaim static TLS. After the optional TLS runs out, TLS access is no longer optimized to use static TLS.) The default setting of rtld.optional_static_tls is 512 so the surplus TLS is 3*192 + 4*144 + 512 = 1664 by default, the same as before. Fixes BZ #25051. Tested on aarch64-linux-gnu and x86_64-linux-gnu. Reviewed-by: Carlos O'Donell <carlos@redhat.com>
* rtld: Account static TLS surplus for audit modulesSzabolcs Nagy2020-07-081-2/+13
| | | | | | | | | | | | | | | | | | | | | | | | | | The new static TLS surplus size computation is surplus_tls = 192 * (nns-1) + 144 * nns + 512 where nns is controlled via the rtld.nns tunable. This commit accounts audit modules too so nns = rtld.nns + audit modules. rtld.nns should only include the namespaces required by the application, namespaces for audit modules are accounted on top of that so audit modules don't use up the static TLS that is reserved for the application. This allows loading many audit modules without tuning rtld.nns or using up static TLS, and it fixes FAIL: elf/tst-auditmany Note that DL_NNS is currently a hard upper limit for nns, and if rtld.nns + audit modules go over the limit that's a fatal error. By default rtld.nns is 4 which allows 12 audit modules. Counting the audit modules is based on existing audit string parsing code, we cannot use GLRO(dl_naudit) before the modules are actually loaded.
* rtld: Add rtld.nns tunable for the number of supported namespacesSzabolcs Nagy2020-07-081-5/+50
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | TLS_STATIC_SURPLUS is 1664 bytes currently which is not enough to support DL_NNS (== 16) number of dynamic link namespaces, if we assume 192 bytes of TLS are reserved for libc use and 144 bytes are reserved for other system libraries that use IE TLS. A new tunable is introduced to control the number of supported namespaces and to adjust the surplus static TLS size as follows: surplus_tls = 192 * (rtld.nns-1) + 144 * rtld.nns + 512 The default is rtld.nns == 4 and then the surplus TLS size is the same as before, so the behaviour is unchanged by default. If an application creates more namespaces than the rtld.nns setting allows, then it is not guaranteed to work, but the limit is not checked. So existing usage will continue to work, but in the future if an application creates more than 4 dynamic link namespaces then the tunable will need to be set. In this patch DL_NNS is a fixed value and provides a maximum to the rtld.nns setting. Static linking used fixed 2048 bytes surplus TLS, this is changed so the same contract is used as for dynamic linking. With static linking DL_NNS == 1 so rtld.nns tunable is forced to 1, so by default the surplus TLS is reduced to 144 + 512 = 656 bytes. This change is not expected to cause problems. Tested on aarch64-linux-gnu and x86_64-linux-gnu. Reviewed-by: Carlos O'Donell <carlos@redhat.com>
* Linux: Perform rseq registration at C startup and thread creationMathieu Desnoyers2020-07-061-1/+7
| | | | | | | | | | | | | | | | | | | Register rseq TLS for each thread (including main), and unregister for each thread (excluding main). "rseq" stands for Restartable Sequences. See the rseq(2) man page proposed here: https://lkml.org/lkml/2018/9/19/647 Those are based on glibc master branch commit 3ee1e0ec5c. The rseq system call was merged into Linux 4.18. The TLS_STATIC_SURPLUS define is increased to leave additional room for dlopen'd initial-exec TLS, which keeps elf/tst-auditmany working. The increase (76 bytes) is larger than 32 bytes because it has not been increased in quite a while. The cost in terms of additional TLS storage is quite significant, but it will also obscure some initial-exec-related dlopen failures.
* Update copyright dates with scripts/update-copyrights.Joseph Myers2020-01-011-1/+1
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* Avoid late dlopen failure due to scope, TLS slotinfo updates [BZ #25112]Florian Weimer2019-11-271-3/+6
| | | | | | | | | | | | | | | | | | | | | | | | This change splits the scope and TLS slotinfo updates in dlopen into two parts: one to resize the data structures, and one to actually apply the update. The call to add_to_global_resize in dl_open_worker is moved before the demarcation point at which no further memory allocations are allowed. _dl_add_to_slotinfo is adjusted to make the list update optional. There is some optimization possibility here because we could grow the slotinfo list of arrays in a single call, one the largest TLS modid is known. This commit does not fix the fatal meory allocation failure in _dl_update_slotinfo. Ideally, this error during dlopen should be recoverable. The update order of scopes and TLS data structures is retained, although it appears to be more correct to fully initialize TLS first, and then expose symbols in the newly loaded objects via the scope update. Tested on x86_64-linux-gnu. Change-Id: I240c58387dabda3ca1bcab48b02115175fa83d6c
* Prefer https to http for gnu.org and fsf.org URLsPaul Eggert2019-09-071-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Also, change sources.redhat.com to sourceware.org. This patch was automatically generated by running the following shell script, which uses GNU sed, and which avoids modifying files imported from upstream: sed -ri ' s,(http|ftp)(://(.*\.)?(gnu|fsf|sourceware)\.org($|[^.]|\.[^a-z])),https\2,g s,(http|ftp)(://(.*\.)?)sources\.redhat\.com($|[^.]|\.[^a-z]),https\2sourceware.org\4,g ' \ $(find $(git ls-files) -prune -type f \ ! -name '*.po' \ ! -name 'ChangeLog*' \ ! -path COPYING ! -path COPYING.LIB \ ! -path manual/fdl-1.3.texi ! -path manual/lgpl-2.1.texi \ ! -path manual/texinfo.tex ! -path scripts/config.guess \ ! -path scripts/config.sub ! -path scripts/install-sh \ ! -path scripts/mkinstalldirs ! -path scripts/move-if-change \ ! -path INSTALL ! -path locale/programs/charmap-kw.h \ ! -path po/libc.pot ! -path sysdeps/gnu/errlist.c \ ! '(' -name configure \ -execdir test -f configure.ac -o -f configure.in ';' ')' \ ! '(' -name preconfigure \ -execdir test -f preconfigure.ac ';' ')' \ -print) and then by running 'make dist-prepare' to regenerate files built from the altered files, and then executing the following to cleanup: chmod a+x sysdeps/unix/sysv/linux/riscv/configure # Omit irrelevant whitespace and comment-only changes, # perhaps from a slightly-different Autoconf version. git checkout -f \ sysdeps/csky/configure \ sysdeps/hppa/configure \ sysdeps/riscv/configure \ sysdeps/unix/sysv/linux/csky/configure # Omit changes that caused a pre-commit check to fail like this: # remote: *** error: sysdeps/powerpc/powerpc64/ppc-mcount.S: trailing lines git checkout -f \ sysdeps/powerpc/powerpc64/ppc-mcount.S \ sysdeps/unix/sysv/linux/s390/s390-64/syscall.S # Omit change that caused a pre-commit check to fail like this: # remote: *** error: sysdeps/sparc/sparc64/multiarch/memcpy-ultra3.S: last line does not end in newline git checkout -f sysdeps/sparc/sparc64/multiarch/memcpy-ultra3.S
* Update copyright dates with scripts/update-copyrights.Joseph Myers2019-01-011-1/+1
| | | | | | | * All files with FSF copyright notices: Update copyright dates using scripts/update-copyrights. * locale/programs/charmap-kw.h: Regenerated. * locale/programs/locfile-kw.h: Likewise.
* Update copyright dates with scripts/update-copyrights.Joseph Myers2018-01-011-1/+1
| | | | | | | * All files with FSF copyright notices: Update copyright dates using scripts/update-copyrights. * locale/programs/charmap-kw.h: Regenerated. * locale/programs/locfile-kw.h: Likewise.
* elf: Remove internal_function attributeFlorian Weimer2017-08-311-6/+0
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* ld.so: Remove internal_function attribute from various functionsFlorian Weimer2017-08-131-3/+0
| | | | | These functions are invoked from other DSOs and should therefore use the standard calling convention.
* Update copyright dates with scripts/update-copyrights.Joseph Myers2017-01-011-1/+1
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* Remove unused function _dl_tls_setupFlorian Weimer2016-12-211-33/+1
| | | | | | Commit 7a5e3d9d633c828d84a9535f26b202a6179978e7 (elf: Assume TLS is initialized in _dl_map_object_from_fd) removed the last call of _dl_tls_setup, but did not remove the function itself.
* [PR19826] fix non-LE TLS in static programsAlexandre Oliva2016-09-211-0/+4
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | An earlier fix for TLS dropped early initialization of DTV entries for modules using static TLS, leaving it for __tls_get_addr to set them up. That worked on platforms that require the GD access model to be relaxed to LE in the main executable, but it caused a regression on platforms that allow GD in the main executable, particularly in statically-linked programs: they use a custom __tls_get_addr that does not update the DTV, which fails when the DTV early initialization is not performed. In static programs, __libc_setup_tls performs the DTV initialization for the main thread, but the DTV of other threads is set up in _dl_allocate_tls_init, so that's the fix that matters. Restoring the initialization in the remaining functions modified by this patch was just for uniformity. It's not clear that it is ever needed: even on platforms that allow GD in the main executable, the dynamically-linked version of __tls_get_addr would set up the DTV entries, even for static TLS modules, while updating the DTV counter. for ChangeLog [BZ #19826] * elf/dl-tls.c (_dl_allocate_tls_init): Restore DTV early initialization of static TLS entries. * elf/dl-reloc.c (_dl_nothread_init_static_tls): Likewise. * nptl/allocatestack.c (init_one_static_tls): Likewise.
* elf: Do not use memalign for TCB/TLS blocks allocation [BZ #17730]Florian Weimer2016-08-031-36/+53
| | | | | | | | | | | | | | | | | | | Instead, call malloc and explicitly align the pointer. There is no external location to store the original (unaligned) pointer, and this commit increases the allocation size to store the pointer at a fixed location relative to the TCB pointer. The manual alignment means that some space goes unused which was previously made available for subsequent allocations. However, in the TLS_DTV_AT_TP case, the manual alignment code avoids aligning the pre-TCB to the TLS block alignment. (Even while using memalign, the allocation had some unused padding in front.) This concludes the removal of memalign calls from the TLS code, and the new tst-tls3-malloc test verifies that only core malloc routines are used.
* elf: Avoid using memalign for TLS allocations [BZ #17730]Florian Weimer2016-08-031-29/+46
| | | | | | | | | | | | Instead of a flag which indicates the pointer can be freed, dtv_t now includes the pointer which should be freed. Due to padding, the size of dtv_t does not increase. To avoid using memalign, the new allocate_dtv_entry function allocates a sufficiently large buffer so that a sub-buffer can be found in it which starts with an aligned pointer. Both the aligned and original pointers are kept, the latter for calling free later.
* Update copyright dates with scripts/update-copyrights.Joseph Myers2016-01-041-1/+1
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* Fix DTV race, assert, DTV_SURPLUS Static TLS limit, and nptl_db garbageAlexandre Oliva2015-03-171-31/+32
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | for ChangeLog [BZ #17090] [BZ #17620] [BZ #17621] [BZ #17628] * NEWS: Update. * elf/dl-tls.c (_dl_update_slotinfo): Clean up outdated DTV entries with Static TLS too. Skip entries past the end of the allocated DTV, from Alan Modra. (tls_get_addr_tail): Update to glibc_likely/unlikely. Move Static TLS DTV entry set up from... (_dl_allocate_tls_init): ... here (fix modid assertion), ... * elf/dl-reloc.c (_dl_nothread_init_static_tls): ... here... * nptl/allocatestack.c (init_one_static_tls): ... and here... * elf/dlopen.c (dl_open_worker): Drop l_tls_modid upper bound for Static TLS. * elf/tlsdeschtab.h (map_generation): Return size_t. Check that the slot we find is associated with the given map before using its generation count. * nptl_db/db_info.c: Include ldsodefs.h. (rtld_global, dtv_slotinfo_list, dtv_slotinfo): New typedefs. * nptl_db/structs.def (DB_RTLD_VARIABLE): New macro. (DB_MAIN_VARIABLE, DB_RTLD_GLOBAL_FIELD): Likewise. (link_map::l_tls_offset): New struct field. (dtv_t::counter): Likewise. (rtld_global): New struct. (_rtld_global): New rtld variable. (dl_tls_dtv_slotinfo_list): New rtld global field. (dtv_slotinfo_list): New struct. (dtv_slotinfo): Likewise. * nptl_db/td_symbol_list.c: Drop gnu/lib-names.h include. (td_lookup): Rename to... (td_mod_lookup): ... this. Use new mod parameter instead of LIBPTHREAD_SO. * nptl_db/td_thr_tlsbase.c: Include link.h. (dtv_slotinfo_list, dtv_slotinfo): New functions. (td_thr_tlsbase): Check DTV generation. Compute Static TLS addresses even if the DTV is out of date or missing them. * nptl_db/fetch-value.c (_td_locate_field): Do not refuse to index zero-length arrays. * nptl_db/thread_dbP.h: Include gnu/lib-names.h. (td_lookup): Make it a macro implemented in terms of... (td_mod_lookup): ... this declaration. * nptl_db/db-symbols.awk (DB_RTLD_VARIABLE): Override. (DB_MAIN_VARIABLE): Likewise.
* Update copyright dates with scripts/update-copyrights.Joseph Myers2015-01-021-1/+1
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* Add hidden __tls_get_addr/___tls_get_addr aliasH.J. Lu2014-12-211-0/+10
| | | | | | | | | | | | | | | | | | | | __tls_get_addr/___tls_get_addr is always defined in ld.so. There is no need to call them via PLT inside ld.so. This patch adds the hidden __tls_get_addr/___tls_get_addr aliases and calls them directly from _dl_tlsdesc_dynamic. There is no need to set up the EBX register in i386 _dl_tlsdesc_dynamic when calling the hidden ___tls_get_addr. * elf/dl-tls.c (__tls_get_addr): Provide the hidden definition if not defined. * sysdeps/i386/dl-tls.h (___tls_get_addr): Provide the hidden definition. * sysdeps/i386/dl-tlsdesc.S (_dl_tlsdesc_dynamic): Call the hidden ___tls_get_addr. * sysdeps/x86_64/dl-tlsdesc.S (_dl_tlsdesc_dynamic): Call the hidden __tls_get_addr. * sysdeps/generic/localplt.data (__tls_get_addr): Removed. * sysdeps/unix/sysv/linux/i386/localplt.data (___tls_get_addr): Likewise.
* Resize DTV if the current DTV isn't big enoughH.J. Lu2014-11-281-41/+61
| | | | | | | | | | | | | | | | | | | | | | | This patch changes _dl_allocate_tls_init to resize DTV if the current DTV isn't big enough. Tested on X86-64, x32 and ia32. [BZ #13862] * elf/dl-tls.c: Include <atomic.h>. (oom): Remove #ifdef SHARED/#endif. (_dl_static_dtv, _dl_initial_dtv): Moved before ... (_dl_resize_dtv): This. Extracted from _dl_update_slotinfo. (_dl_allocate_tls_init): Resize DTV if the current DTV isn't big enough. (_dl_update_slotinfo): Call _dl_resize_dtv to resize DTV. * nptl/Makefile (tests): Add tst-stack4. (modules-names): Add tst-stack4mod. ($(objpfx)tst-stack4): New. (tst-stack4mod.sos): Likewise. ($(objpfx)tst-stack4.out): Likewise. ($(tst-stack4mod.sos)): Likewise. (clean): Likewise. * nptl/tst-stack4.c: New file. * nptl/tst-stack4mod.c: Likewise.
* BZ #16613: Support TLS in audit libraries.Carlos O'Donell2014-02-251-0/+28
| | | | | | | | | | | This commit fixes a bug where the dynamic loader would crash when loading audit libraries, via LD_AUDIT, where those libraries used TLS. The dynamic loader was not considering that the audit libraries would use TLS and failed to bump the TLS generation counter leaving TLS usage inconsistent after loading the audit libraries. https://sourceware.org/ml/libc-alpha/2014-02/msg00569.html
* Use glibc_likely instead __builtin_expect.Ondřej Bílka2014-02-101-8/+8
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* Revert "Patch 3/4 of the effort to make TLS access async-signal-safe."Allan McRae2014-02-061-12/+0
| | | | This reverts commit 35e8f7ab94c910659de9d507aa0f3e1f8973d914.
* Revert "Patch 2/4 of the effort to make TLS access async-signal-safe."Allan McRae2014-02-061-18/+16
| | | | | | | | | | | | | This reverts commit 1f33d36a8a9e78c81bed59b47f260723f56bb7e6. Conflicts: elf/dl-misc.c Also reverts the follow commits that were bug fixes to new code introduced in the above commit: 063b2acbce83549df82ab30f5af573f1b9c4bd19 b627fdd58554bc36bd344dc40a8787c4b7a9cc46 e81c64bba13d2d8b2a4e53254a82cc80f27c8497
* Revert "Async-signal safe TLS."Allan McRae2014-02-061-67/+33
| | | | | | | | | This reverts commit 7f507ee17aee720fa423fa38502bc3caa0dd03d7. Conflicts: ChangeLog nptl/tst-tls7.c nptl/tst-tls7mod.c
* Async-signal safe TLS.Andrew Hunter2014-01-031-33/+67
| | | | | | | | | | | | | | | | | | | | | | ChangeLog: 2014-01-03 Andrew Hunter <ahh@google.com> * elf/dl-open.c (): New comment. * elf/dl-reloc.c (_dl_try_allocate_static_tls): Use atomic_compare_and_exchange_bool_acq (_dl_allocate_static_tls): Block signals. * elf/dl-tls.c (allocate_and_init): Return void. (_dl_update_slotinfo): Block signals, use atomic update. nptl/ChangeLog: 2014-01-03 Andrew Hunter <ahh@google.com> * nptl/Makefile (tst-tls7): New test. * nptl/tst-tls7.c: New file. * nptl/tst-tls7mod.c: New file. * nptl/allocatestack.c (init_one_static_tls): Use atomic barrier.
* Update copyright notices with scripts/update-copyrightsAllan McRae2014-01-011-1/+1
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* Patch 2/4 of the effort to make TLS access async-signal-safe.Paul Pluzhnikov2013-12-181-16/+18
| | | | | | | | | | | | | | | | | Add a signal-safe malloc replacement. 2013-12-18 Andrew Hunter <ahh@google.com> * sysdeps/generic/ldsodefs.h (__signal_safe_memalign): New prototype. (__signal_safe_malloc, __signal_safe_free): Likewise. (__signal_safe_realloc, __signal_safe_calloc): Likewise. * elf/dl-misc.c (__signal_safe_allocator_header): New struct. (__signal_safe_memalign, __signal_safe_malloc): New function. (__signal_safe_free, __signal_safe_realloc): Likewise. (__signal_safe_calloc): Likewise. * elf/dl-tls.c (allocate_dtv, _dl_clear_dtv): Call signal-safe functions. (_dl_deallocate_tls, _dl_update_slotinfo): Likewise.
* Patch 3/4 of the effort to make TLS access async-signal-safe.Paul Pluzhnikov2013-12-181-0/+12
| | | | | | | | | | | Factor out _dl_clear_dtv. 2013-12-18 Andrew Hunter <ahh@google.com> * elf/Versions (ld): Add _dl_clear_dtv. * sysdeps/generic/ldsodefs.h (_dl_clear_dtv): New prototype. * elf/dl-tls.c (_dl_clear_dtv): New function. * nptl/allocatestack.c (get_cached_stack): Call _dl_clear_dtv.
* Update copyright notices with scripts/update-copyrights.Joseph Myers2013-01-021-1/+1
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