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* elf: Assume disjointed .rela.dyn and .rela.plt for loaderAdhemerval Zanella2021-11-021-23/+9
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | The patch removes the the ELF_DURING_STARTUP optimization and assume both .rel.dyn and .rel.plt might not be subsequent. This allows some code simplification since relocation will be handled independently where it is done on bootstrap. At least on x86_64_64, I can not measure any performance implications. Running 10000 time the command LD_DEBUG=statistics ./elf/ld.so ./libc.so And filtering the "total startup time in dynamic loader" result, the geometric mean is: patched master Ryzen 7 5900x 24140 24952 i7-4510U 45957 45982 (The results do show some variation, I did not make any statistical analysis). It also allows build arm with lld, since it inserts ".ARM.exidx" between ".rel.dyn" and ".rel.plt" for the loader. Checked on x86_64-linux-gnu and arm-linux-gnueabihf. Reviewed-by: H.J. Lu <hjl.tools@gmail.com>
* elf: Disable ifuncmain{1,5,5pic,5pie} when using LLDAdhemerval Zanella2021-10-291-4/+13
| | | | | | | | | These tests takes the address of a protected symbol (foo_protected) and lld does not support copy relocations on protected data symbols. Checked on x86_64-linux-gnu. Reviewed-by: Fangrui Song <maskray@google.com>
* elf: Make global.out depend on reldepmod4.so [BZ #28457]H.J. Lu2021-10-251-1/+1
| | | | | | The global test is linked with globalmod1.so which dlopens reldepmod4.so. Make global.out depend on reldepmod4.so. This fixes BZ #28457. Reviewed-by: Florian Weimer <fweimer@redhat.com>
* elf: Fix slow DSO sorting behavior in dynamic loader (BZ #17645)Chung-Lin Tang2021-10-2110-41/+231
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | This second patch contains the actual implementation of a new sorting algorithm for shared objects in the dynamic loader, which solves the slow behavior that the current "old" algorithm falls into when the DSO set contains circular dependencies. The new algorithm implemented here is simply depth-first search (DFS) to obtain the Reverse-Post Order (RPO) sequence, a topological sort. A new l_visited:1 bitfield is added to struct link_map to more elegantly facilitate such a search. The DFS algorithm is applied to the input maps[nmap-1] backwards towards maps[0]. This has the effect of a more "shallow" recursion depth in general since the input is in BFS. Also, when combined with the natural order of processing l_initfini[] at each node, this creates a resulting output sorting closer to the intuitive "left-to-right" order in most cases. Another notable implementation adjustment related to this _dl_sort_maps change is the removing of two char arrays 'used' and 'done' in _dl_close_worker to represent two per-map attributes. This has been changed to simply use two new bit-fields l_map_used:1, l_map_done:1 added to struct link_map. This also allows discarding the clunky 'used' array sorting that _dl_sort_maps had to sometimes do along the way. Tunable support for switching between different sorting algorithms at runtime is also added. A new tunable 'glibc.rtld.dynamic_sort' with current valid values 1 (old algorithm) and 2 (new DFS algorithm) has been added. At time of commit of this patch, the default setting is 1 (old algorithm). Signed-off-by: Chung-Lin Tang <cltang@codesourcery.com> Reviewed-by: Adhemerval Zanella <adhemerval.zanella@linaro.org>
* elf: Testing infrastructure for ld.so DSO sorting (BZ #17645)Chung-Lin Tang2021-10-213-0/+695
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | This is the first of a 2-part patch set that fixes slow DSO sorting behavior in the dynamic loader, as reported in BZ #17645. In order to facilitate such a large modification to the dynamic loader, this first patch implements a testing framework for validating shared object sorting behavior, to enable comparison between old/new sorting algorithms, and any later enhancements. This testing infrastructure consists of a Python script scripts/dso-ordering-test.py' which takes in a description language, consisting of strings that describe a set of link dependency relations between DSOs, and generates testcase programs and Makefile fragments to automatically test the described situation, for example: a->b->c->d # four objects linked one after another a->[bc]->d;b->c # a depends on b and c, which both depend on d, # b depends on c (b,c linked to object a in fixed order) a->b->c;{+a;%a;-a} # a, b, c serially dependent, main program uses # dlopen/dlsym/dlclose on object a a->b->c;{}!->[abc] # a, b, c serially dependent; multiple tests generated # to test all permutations of a, b, c ordering linked # to main program (Above is just a short description of what the script can do, more documentation is in the script comments.) Two files containing several new tests, elf/dso-sort-tests-[12].def are added, including test scenarios for BZ #15311 and Redhat issue #1162810 [1]. Due to the nature of dynamic loader tests, where the sorting behavior and test output occurs before/after main(), generating testcases to use support/test-driver.c does not suffice to control meaningful timeout for ld.so. Therefore a new utility program 'support/test-run-command', based on test-driver.c/support_test_main.c has been added. This does the same testcase control, but for a program specified through a command-line rather than at the source code level. This utility is used to run the dynamic loader testcases generated by dso-ordering-test.py. [1] https://bugzilla.redhat.com/show_bug.cgi?id=1162810 Signed-off-by: Chung-Lin Tang <cltang@codesourcery.com> Reviewed-by: Adhemerval Zanella <adhemerval.zanella@linaro.org>
* Correct access attribute on memfrob (bug 28475)Joseph Myers2021-10-203-3/+3
| | | | | | | | | | | | | | | | | | | | | | | As noted in bug 28475, the access attribute on memfrob in <string.h> is incorrect: the function both reads and writes the memory pointed to by its argument, so it needs to use __read_write__, not __write_only__. This incorrect attribute results in a build failure for accessing uninitialized memory for s390x-linux-gnu-O3 with build-many-glibcs.py using GCC mainline. Correct the attribute. Fixing this shows up that some calls to memfrob in elf/ tests are reading uninitialized memory; I'm not entirely sure of the purpose of those calls, but guess they are about ensuring that the stack space is indeed allocated at that point in the function, and so it matters that they are calling a function whose semantics are unknown to the compiler. Thus, change the first memfrob call in those tests to use explicit_bzero instead, as suggested by Florian in <https://sourceware.org/pipermail/libc-alpha/2021-October/132119.html>, to avoid the use of uninitialized memory. Tested for x86_64, and with build-many-glibcs.py (GCC mainline) for s390x-linux-gnu-O3.
* ld.so: Initialize bootstrap_map.l_ld_readonly [BZ #28340]H.J. Lu2021-10-191-0/+1
| | | | | | | | | | | | | | | 1. Define DL_RO_DYN_SECTION to initalize bootstrap_map.l_ld_readonly before calling elf_get_dynamic_info to get dynamic info in bootstrap_map, 2. Define a single static inline bool dl_relocate_ld (const struct link_map *l) { /* Don't relocate dynamic section if it is readonly */ return !(l->l_ld_readonly || DL_RO_DYN_SECTION); } This updates BZ #28340 fix.
* elf: Fix elf_get_dynamic_info() for bootstrapAdhemerval Zanella2021-10-185-45/+61
| | | | | | | | | | | | | | | | | | | THe d6d89608ac8c broke powerpc for --enable-bind-now because it turned out that different than patch assumption rtld elf_get_dynamic_info() does require to handle RTLD_BOOTSTRAP to avoid DT_FLAGS and DT_RUNPATH (more specially the GLRO usage which is not reallocate yet). This patch fixes by passing two arguments to elf_get_dynamic_info() to inform that by rtld (bootstrap) or static pie initialization (static_pie_bootstrap). I think using explicit argument is way more clear and burried C preprocessor, and compiler should remove the dead code. I checked on x86_64 and i686 with default options, --enable-bind-now, and --enable-bind-now and --enable--static-pie. I also check on aarch64, armhf, powerpc64, and powerpc with default and --enable-bind-now.
* elf: Fix dynamic-link.h usage on rtld.cAdhemerval Zanella2021-10-147-65/+73
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The 4af6982e4c fix does not fully handle RTLD_BOOTSTRAP usage on rtld.c due two issues: 1. RTLD_BOOTSTRAP is also used on dl-machine.h on various architectures and it changes the semantics of various machine relocation functions. 2. The elf_get_dynamic_info() change was done sideways, previously to 490e6c62aa get-dynamic-info.h was included by the first dynamic-link.h include *without* RTLD_BOOTSTRAP being defined. It means that the code within elf_get_dynamic_info() that uses RTLD_BOOTSTRAP is in fact unused. To fix 1. this patch now includes dynamic-link.h only once with RTLD_BOOTSTRAP defined. The ELF_DYNAMIC_RELOCATE call will now have the relocation fnctions with the expected semantics for the loader. And to fix 2. part of 4af6982e4c is reverted (the check argument elf_get_dynamic_info() is not required) and the RTLD_BOOTSTRAP pieces are removed. To reorganize the includes the static TLS definition is moved to its own header to avoid a circular dependency (it is defined on dynamic-link.h and dl-machine.h requires it at same time other dynamic-link.h definition requires dl-machine.h defitions). Also ELF_MACHINE_NO_REL, ELF_MACHINE_NO_RELA, and ELF_MACHINE_PLT_REL are moved to its own header. Only ancient ABIs need special values (arm, i386, and mips), so a generic one is used as default. The powerpc Elf64_FuncDesc is also moved to its own header, since csu code required its definition (which would require either include elf/ folder or add a full path with elf/). Checked on x86_64, i686, aarch64, armhf, powerpc64, powerpc32, and powerpc64le. Reviewed-by: Szabolcs Nagy <szabolcs.nagy@arm.com>
* elf: Update audit tests to not depend on stdoutStafford Horne2021-10-127-125/+22
| | | | | | | | | | | | | | The tst-audit14, tst-audit15 and tst-audit16 tests all have audit modules that write to stdout; the test reads from stdout to confirm what was written. This assumes the stdout is a file which is not the case when run over ssh. This patch updates the tests to use a post run cmp command to compare the output against and .exp file. This is similar to how many other tests work and it fixes the stdout limitation. Also, this means the test code can be greatly simplified. Reviewed-by: Adhemerval Zanella <adhemerval.zanella@linaro.org>
* elf: Fix elf_get_dynamic_info definitionAdhemerval Zanella2021-10-128-17/+24
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Before to 490e6c62aa31a8a ('elf: Avoid nested functions in the loader [BZ #27220]'), elf_get_dynamic_info() was defined twice on rtld.c: on the first dynamic-link.h include and later within _dl_start(). The former definition did not define DONT_USE_BOOTSTRAP_MAP and it is used on setup_vdso() (since it is a global definition), while the former does define DONT_USE_BOOTSTRAP_MAP and it is used on loader self-relocation. With the commit change, the function is now included and defined once instead of defined as a nested function. So rtld.c defines without defining RTLD_BOOTSTRAP and it brokes at least powerpc32. This patch fixes by moving the get-dynamic-info.h include out of dynamic-link.h, which then the caller can corirectly set the expected semantic by defining STATIC_PIE_BOOTSTRAP, RTLD_BOOTSTRAP, and/or RESOLVE_MAP. It also required to enable some asserts only for the loader bootstrap to avoid issues when called from setup_vdso(). As a side note, this is another issues with nested functions: it is not clear from pre-processed output (-E -dD) how the function will be build and its semantic (since nested function will be local and extra C defines may change it). I checked on x86_64-linux-gnu (w/o --enable-static-pie), i686-linux-gnu, powerpc64-linux-gnu, powerpc-linux-gnu-power4, aarch64-linux-gnu, arm-linux-gnu, sparc64-linux-gnu, and s390x-linux-gnu. Reviewed-by: Fangrui Song <maskray@google.com>
* elf: Avoid nested functions in the loader [BZ #27220]Fangrui Song2021-10-077-107/+108
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | dynamic-link.h is included more than once in some elf/ files (rtld.c, dl-conflict.c, dl-reloc.c, dl-reloc-static-pie.c) and uses GCC nested functions. This harms readability and the nested functions usage is the biggest obstacle prevents Clang build (Clang doesn't support GCC nested functions). The key idea for unnesting is to add extra parameters (struct link_map *and struct r_scope_elm *[]) to RESOLVE_MAP, ELF_MACHINE_BEFORE_RTLD_RELOC, ELF_DYNAMIC_RELOCATE, elf_machine_rel[a], elf_machine_lazy_rel, and elf_machine_runtime_setup. (This is inspired by Stan Shebs' ppc64/x86-64 implementation in the google/grte/v5-2.27/master which uses mixed extra parameters and static variables.) Future simplification: * If mips elf_machine_runtime_setup no longer needs RESOLVE_GOTSYM, elf_machine_runtime_setup can drop the `scope` parameter. * If TLSDESC no longer need to be in elf_machine_lazy_rel, elf_machine_lazy_rel can drop the `scope` parameter. Tested on aarch64, i386, x86-64, powerpc64le, powerpc64, powerpc32, sparc64, sparcv9, s390x, s390, hppa, ia64, armhf, alpha, and mips64. In addition, tested build-many-glibcs.py with {arc,csky,microblaze,nios2}-linux-gnu and riscv64-linux-gnu-rv64imafdc-lp64d. Reviewed-by: Adhemerval Zanella <adhemerval.zanella@linaro.org>
* Add run-time check for indirect external accessH.J. Lu2021-10-071-0/+5
| | | | | | | | | | | | | When performing symbol lookup for references in executable without indirect external access: 1. Disallow copy relocations in executable against protected data symbols in a shared object with indirect external access. 2. Disallow non-zero symbol values of undefined function symbols in executable, which are used as the function pointer, against protected function symbols in a shared object with indirect external access. Reviewed-by: Adhemerval Zanella <adhemerval.zanella@linaro.org>
* Initial support for GNU_PROPERTY_1_NEEDEDH.J. Lu2021-10-071-0/+17
| | | | | | | | | | | | | | | | | 1. Add GNU_PROPERTY_1_NEEDED: #define GNU_PROPERTY_1_NEEDED GNU_PROPERTY_UINT32_OR_LO to indicate the needed properties by the object file. 2. Add GNU_PROPERTY_1_NEEDED_INDIRECT_EXTERN_ACCESS: #define GNU_PROPERTY_1_NEEDED_INDIRECT_EXTERN_ACCESS (1U << 0) to indicate that the object file requires canonical function pointers and cannot be used with copy relocation. 3. Scan GNU_PROPERTY_1_NEEDED property and store it in l_1_needed. Reviewed-by: Adhemerval Zanella <adhemerval.zanella@linaro.org>
* ld.so: Don't fill the DT_DEBUG entry in ld.so [BZ #28129]H.J. Lu2021-10-061-6/+0
| | | | | | Linker creates the DT_DEBUG entry only in executables. Don't fill the non-existent DT_DEBUG entry in ld.so with the run-time address of the r_debug structure. This fixes BZ #28129.
* elf: Avoid deadlock between pthread_create and ctors [BZ #28357]Szabolcs Nagy2021-10-045-9/+56
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | 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 nsid with args.nsid [BZ #27609]H.J. Lu2021-09-301-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | commit ec935dea6332cb22f9881cd1162bad156173f4b0 Author: Florian Weimer <fweimer@redhat.com> Date: Fri Apr 24 22:31:15 2020 +0200 elf: Implement __libc_early_init has @@ -856,6 +876,11 @@ no more namespaces available for dlmopen()")); /* See if an error occurred during loading. */ if (__glibc_unlikely (exception.errstring != NULL)) { + /* Avoid keeping around a dangling reference to the libc.so link + map in case it has been cached in libc_map. */ + if (!args.libc_already_loaded) + GL(dl_ns)[nsid].libc_map = NULL; + do_dlopen calls _dl_open with nsid == __LM_ID_CALLER (-2), which calls dl_open_worker with args.nsid = nsid. dl_open_worker updates args.nsid if it is __LM_ID_CALLER. After dl_open_worker returns, it is wrong to use nsid. Replace nsid with args.nsid after dl_open_worker returns. This fixes BZ #27609.
* elf: Copy l_addr/l_ld when adding ld.so to a new namespaceH.J. Lu2021-09-291-0/+4
| | | | | | | | | | | | When add ld.so to a new namespace, we don't actually load ld.so. We create a new link map and refers the real one for almost everything. Copy l_addr and l_ld from the real ld.so link map to avoid GDB warning: warning: .dynamic section for ".../elf/ld-linux-x86-64.so.2" is not at the expected address (wrong library or version mismatch?) when handling shared library loaded by dlmopen. Reviewed-by: Adhemerval Zanella <adhemerval.zanella@linaro.org>
* Avoid warning: overriding recipe for .../tst-ro-dynamic-mod.soH.J. Lu2021-09-251-2/+3
| | | | | | | | 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.
* ld.so: Replace DL_RO_DYN_SECTION with dl_relocate_ld [BZ #28340]H.J. Lu2021-09-229-27/+97
| | | | | | | | | | | | | | | | | 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>
* elf: Include <sysdep.h> in elf/dl-debug-symbols.SFlorian Weimer2021-09-201-0/+4
| | | | | | | This is necessary to generate assembler marker sections on some targets. Reviewed-by: Szabolcs Nagy <szabolcs.nagy@arm.com>
* Extend struct r_debug to support multiple namespaces [BZ #15971]H.J. Lu2021-09-1911-40/+226
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Glibc does not provide an interface for debugger to access libraries loaded in multiple namespaces via dlmopen. The current rtld-debugger interface is described in the file: elf/rtld-debugger-interface.txt under the "Standard debugger interface" heading. This interface only provides access to the first link-map (LM_ID_BASE). 1. Bump r_version to 2 when multiple namespaces are used. This triggers the GDB bug: https://sourceware.org/bugzilla/show_bug.cgi?id=28236 2. Add struct r_debug_extended to extend struct r_debug into a linked-list, where each element correlates to an unique namespace. 3. Initialize the r_debug_extended structure. Bump r_version to 2 for the new namespace and add the new namespace to the namespace linked list. 4. Add _dl_debug_update to return the address of struct r_debug' of a namespace. 5. Add a hidden symbol, _r_debug_extended, for struct r_debug_extended. 6. Provide the symbol, _r_debug, with size of struct r_debug, as an alias of _r_debug_extended, for programs which reference _r_debug. This fixes BZ #15971. Reviewed-by: Florian Weimer <fweimer@redhat.com>
* elf: Remove THREAD_GSCOPE_IN_TCBSergey Bugaev2021-09-161-3/+0
| | | | | | | | | 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>
* elf: Replace most uses of THREAD_GSCOPE_IN_TCBSergey Bugaev2021-09-154-8/+10
| | | | | | | | | | | | | | | | | | | | | | 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>
* Remove "Contributed by" linesSiddhesh Poyarekar2021-09-0324-26/+0
| | | | | | | | | | | | | | | | | | | | | | | | | | 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>
* elf: Skip tst-auditlogmod-* if the linker doesn't support --depaudit [BZ #28151]Fangrui Song2021-08-241-1/+3
| | | | | | gold and ld.lld do not support --audit or --depaudit. Reviewed-by: Adhemerval Zanella <adhemerval.zanella@linaro.org>
* rtld: copy terminating null in tunables_strdup (bug 28256)Andreas Schwab2021-08-231-2/+0
| | | | | | 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.
* elf: Fix missing colon in LD_SHOW_AUXV output [BZ #28253]Arjun Shankar2021-08-201-1/+1
| | | | | This commit adds a missing colon in the AT_MINSIGSTKSZ entry in the _dl_show_auxv function.
* elf: Drop elf/tls-macros.h in favor of __thread and tls_model attributes [BZ ↵Fangrui Song2021-08-1611-193/+60
| | | | | | | | | | | | | | | | | | | | | | | | | | #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>
* elf: Unconditionally use __ehdr_startFangrui Song2021-08-101-9/+4
| | | | | | | | | | | | | 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>
* ldconfig: avoid leak on empty paths in config fileSiddhesh Poyarekar2021-08-031-1/+5
| | | | Reviewed-by: Arjun Shankar <arjun@redhat.com>
* elf: Fix audit regressionAdhemerval Zanella2021-07-304-10/+61
| | | | | | | 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.
* Move malloc hooks into a compat DSOSiddhesh Poyarekar2021-07-222-10/+6
| | | | | | | | | | | | | | | | | | | | | | | | 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>
* elf: Fix a wrong array access on tst-tls20Adhemerval Zanella2021-07-161-4/+4
| | | | Check on x86_64-linux-gnu with --enable-stack-protector=all.
* elf: Add -Wl,--no-as-needed for tst-tls-manydynamic*mod-dep-bad.so (BZ #28089)Adhemerval Zanella2021-07-151-0/+11
| | | | | | | 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.
* elf: Fix DTV gap reuse logic (BZ #27135)Adhemerval Zanella2021-07-147-31/+347
| | | | | | | | | | | | | | | | | | | | | | | | | | 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>
* Force building with -fno-commonFlorian Weimer2021-07-092-5/+4
| | | | | | | | | | 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>
* Add NT_ARM_PAC_ENABLED_KEYS to elf.hJoseph Myers2021-07-081-0/+2
| | | | | | | This patch adds the new NT_ARM_PAC_ENABLED_KEYS constant from Linux 5.13 to glibc's elf.h. Tested for x86_64.
* elf/tests: Make thrlock and noload depend on libmSiddhesh Poyarekar2021-07-081-0/+2
| | | | | | | 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>
* elf: Clean up GLIBC_PRIVATE exports of internal libdl symbolsFlorian Weimer2021-07-079-243/+4
| | | | | | | | 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>
* elf: Call free from base namespace on error in dl-libc.c [BZ #27646]Florian Weimer2021-07-061-1/+1
| | | | | | | | | | | | 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]").
* Linux: Cleanups after librt moveFlorian Weimer2021-06-281-1/+3
| | | | | | | | | | | | 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>
* Install shared objects under their ABI namesFlorian Weimer2021-06-281-8/+2
| | | | | | | | | | | | | 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>
* elf: Generalize name-based DSO recognition in ldconfigFlorian Weimer2021-06-284-4/+72
| | | | | | | | | 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>
* elf: Disable most of TLS modid gaps processing [BZ #27135]Florian Weimer2021-06-253-6/+15
| | | | | | | | | | | | | 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).
* elf: Fix glibc-hwcaps priorities with cache flags mismatches [BZ #27046]Florian Weimer2021-06-251-64/+60
| | | | | | | | | | | | | | | | | | | | 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>
* Use 64 bit time_t stat internallyAdhemerval Zanella2021-06-223-8/+8
| | | | | | | | | | 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>
* elf: Use _dl_catch_error from base namespace in dl-libc.c [BZ #27646]Florian Weimer2021-06-174-3/+66
| | | | | | | | | | | 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>
* Remove stale references to libdl.aFlorian Weimer2021-06-091-6/+1
| | | | | | | | 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>
* Fix elf/tst-tls9-static after libdl cleanups.Stefan Liebler2021-06-091-2/+0
| | | | | | | | | | | | 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.