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* elf: Add _dl_find_object functionFlorian Weimer2021-12-2823-4/+1697
| | | | | | | | | | | | | | | | | | | | | | | | | It can be used to speed up the libgcc unwinder, and the internal _dl_find_dso_for_object function (which is used for caller identification in dlopen and related functions, and in dladdr). _dl_find_object is in the internal namespace due to bug 28503. If libgcc switches to _dl_find_object, this namespace issue will be fixed. It is located in libc for two reasons: it is necessary to forward the call to the static libc after static dlopen, and there is a link ordering issue with -static-libgcc and libgcc_eh.a because libc.so is not a linker script that includes ld.so in the glibc build tree (so that GCC's internal -lc after libgcc_eh.a does not pick up ld.so). It is necessary to do the i386 customization in the sysdeps/x86/bits/dl_find_object.h header shared with x86-64 because otherwise, multilib installations are broken. The implementation uses software transactional memory, as suggested by Torvald Riegel. Two copies of the supporting data structures are used, also achieving full async-signal-safety. Reviewed-by: Adhemerval Zanella <adhemerval.zanella@linaro.org>
* elf: Do not fail for failed dlmopen on audit modules (BZ #28061)Adhemerval Zanella2021-12-284-2/+87
| | | | | | | | | | | | | | | | | | | | | The dl_main sets the LM_ID_BASE to RT_ADD just before starting to add load new shared objects. The state is set to RT_CONSISTENT just after all objects are loaded. However if a audit modules tries to dlmopen an inexistent module, the _dl_open will assert that the namespace is in an inconsistent state. This is different than dlopen, since first it will not use LM_ID_BASE and second _dl_map_object_from_fd is the sole responsible to set and reset the r_state value. So the assert on _dl_open can not really be seen if the state is consistent, since _dt_main resets it. This patch removes the assert. Checked on x86_64-linux-gnu, i686-linux-gnu, and aarch64-linux-gnu. Reviewed-by: Florian Weimer <fweimer@redhat.com>
* elf: Issue audit la_objopen for vDSOAdhemerval Zanella2021-12-286-8/+197
| | | | | | | | | | | | | | | The vDSO is is listed in the link_map chain, but is never the subject of an la_objopen call. A new internal flag __RTLD_VDSO is added that acts as __RTLD_OPENEXEC to allocate the required 'struct auditstate' extra space for the 'struct link_map'. The return value from the callback is currently ignored, since there is no PLT call involved by glibc when using the vDSO, neither the vDSO are exported directly. Checked on x86_64-linux-gnu, i686-linux-gnu, and aarch64-linux-gnu. Reviewed-by: Florian Weimer <fweimer@redhat.com>
* elf: Add audit tests for modules with TLSDESCAdhemerval Zanella2021-12-286-0/+242
| | | | | | Checked on x86_64-linux-gnu, i686-linux-gnu, and aarch64-linux-gnu. Reviewed-by: Florian Weimer <fweimer@redhat.com>
* elf: Avoid unnecessary slowdown from profiling with audit (BZ#15533)Adhemerval Zanella2021-12-289-10/+289
| | | | | | | | | | | | | | | | | | | The rtld-audit interfaces introduces a slowdown due to enabling profiling instrumentation (as if LD_AUDIT implied LD_PROFILE). However, instrumenting is only necessary if one of audit libraries provides PLT callbacks (la_pltenter or la_pltexit symbols). Otherwise, the slowdown can be avoided. The following patch adjusts the logic that enables profiling to iterate over all audit modules and check if any of those provides a PLT hook. To keep la_symbind to work even without PLT callbacks, _dl_fixup now calls the audit callback if the modules implements it. Co-authored-by: Alexander Monakov <amonakov@ispras.ru> Checked on x86_64-linux-gnu, i686-linux-gnu, and aarch64-linux-gnu. Reviewed-by: Florian Weimer <fweimer@redhat.com>
* elf: Add _dl_audit_pltexitAdhemerval Zanella2021-12-283-66/+58
| | | | | | | | | It consolidates the code required to call la_pltexit audit callback. Checked on x86_64-linux-gnu, i686-linux-gnu, and aarch64-linux-gnu. Reviewed-by: Florian Weimer <fweimer@redhat.com>
* elf: Add _dl_audit_pltenterAdhemerval Zanella2021-12-282-72/+78
| | | | | | | | | It consolidates the code required to call la_pltenter audit callback. Checked on x86_64-linux-gnu, i686-linux-gnu, and aarch64-linux-gnu. Reviewed-by: Florian Weimer <fweimer@redhat.com>
* elf: Add _dl_audit_preinitAdhemerval Zanella2021-12-282-1/+16
| | | | | | | | | It consolidates the code required to call la_preinit audit callback. Checked on x86_64-linux-gnu, i686-linux-gnu, and aarch64-linux-gnu. Reviewed-by: Florian Weimer <fweimer@redhat.com>
* elf: Add _dl_audit_symbind_alt and _dl_audit_symbindAdhemerval Zanella2021-12-284-124/+125
| | | | | | | | | It consolidates the code required to call la_symbind{32,64} audit callback. Checked on x86_64-linux-gnu, i686-linux-gnu, and aarch64-linux-gnu. Reviewed-by: Florian Weimer <fweimer@redhat.com>
* elf: Add _dl_audit_objcloseAdhemerval Zanella2021-12-283-34/+23
| | | | | | | | | It consolidates the code required to call la_objclose audit callback. Checked on x86_64-linux-gnu, i686-linux-gnu, and aarch64-linux-gnu. Reviewed-by: Florian Weimer <fweimer@redhat.com>
* elf: Add _dl_audit_objsearchAdhemerval Zanella2021-12-282-49/+40
| | | | | | | | | It consolidates the code required to call la_objsearch audit callback. Checked on x86_64-linux-gnu, i686-linux-gnu, and aarch64-linux-gnu. Reviewed-by: Florian Weimer <fweimer@redhat.com>
* elf: Add _dl_audit_activity_map and _dl_audit_activity_nsidAdhemerval Zanella2021-12-285-111/+35
| | | | | | | | | | | | | It consolidates the code required to call la_activity audit callback. Also for a new Lmid_t the namespace link_map list are empty, so it requires to check if before using it. This can happen for when audit module is used along with dlmopen. Checked on x86_64-linux-gnu, i686-linux-gnu, and aarch64-linux-gnu. Reviewed-by: Florian Weimer <fweimer@redhat.com>
* elf: Add _dl_audit_objopenAdhemerval Zanella2021-12-284-38/+44
| | | | | | | | It consolidates the code required to call la_objopen audit callback. Checked on x86_64-linux-gnu, i686-linux-gnu, and aarch64-linux-gnu. Reviewed-by: Florian Weimer <fweimer@redhat.com>
* elf: Remove AArch64 from comment for AT_MINSIGSTKSZH.J. Lu2021-12-231-2/+1
| | | | | | | | | | | | | | | | | Remove AArch64 from comment for AT_MINSIGSTKSZ to match commit 7cd60e43a6def40ecb75deb8decc677995970d0b Author: Chang S. Bae <chang.seok.bae@intel.com> Date: Tue May 18 13:03:15 2021 -0700 uapi/auxvec: Define the aux vector AT_MINSIGSTKSZ Define AT_MINSIGSTKSZ in the generic uapi header. It is already used as generic ABI in glibc's generic elf.h, and this define will prevent future namespace conflicts. In particular, x86 is also using this generic definition. in Linux kernel 5.14.
* elf: Remove unused NEED_DL_BASE_ADDR and _dl_base_addrFlorian Weimer2021-12-231-8/+0
| | | | Reviewed-by: Adhemerval Zanella <adhemerval.zanella@linaro.org>
* elf: Remove excessive p_align check on PT_LOAD segments [BZ #28688]H.J. Lu2021-12-221-7/+2
| | | | | | | | | | p_align does not have to be a multiple of the page size. Only PT_LOAD segment layout should be aligned to the page size. 1: Remove p_align check against the page size. 2. Use the page size, instead of p_align, to check PT_LOAD segment layout. Reviewed-by: Florian Weimer <fweimer@redhat.com>
* malloc: Add Huge Page support for mmapAdhemerval Zanella2021-12-152-3/+2
| | | | | | | | | | | | | | | | | | | | | | | | | | | | With the morecore hook removed, there is not easy way to provide huge pages support on with glibc allocator without resorting to transparent huge pages. And some users and programs do prefer to use the huge pages directly instead of THP for multiple reasons: no splitting, re-merging by the VM, no TLB shootdowns for running processes, fast allocation from the reserve pool, no competition with the rest of the processes unlike THP, no swapping all, etc. This patch extends the 'glibc.malloc.hugetlb' tunable: the value '2' means to use huge pages directly with the system default size, while a positive value means and specific page size that is matched against the supported ones by the system. Currently only memory allocated on sysmalloc() is handled, the arenas still uses the default system page size. To test is a new rule is added tests-malloc-hugetlb2, which run the addes tests with the required GLIBC_TUNABLE setting. On systems without a reserved huge pages pool, is just stress the mmap(MAP_HUGETLB) allocation failure. To improve test coverage it is required to create a pool with some allocated pages. Checked on x86_64-linux-gnu. Reviewed-by: DJ Delorie <dj@redhat.com>
* malloc: Add madvise support for Transparent Huge PagesAdhemerval Zanella2021-12-152-0/+6
| | | | | | | | | | | | | | | | | | | | | | | | | | Linux Transparent Huge Pages (THP) current supports three different states: 'never', 'madvise', and 'always'. The 'never' is self-explanatory and 'always' will enable THP for all anonymous pages. However, 'madvise' is still the default for some system and for such case THP will be only used if the memory range is explicity advertise by the program through a madvise(MADV_HUGEPAGE) call. To enable it a new tunable is provided, 'glibc.malloc.hugetlb', where setting to a value diffent than 0 enables the madvise call. This patch issues the madvise(MADV_HUGEPAGE) call after a successful mmap() call at sysmalloc() with sizes larger than the default huge page size. The madvise() call is disable is system does not support THP or if it has the mode set to "never" and on Linux only support one page size for THP, even if the architecture supports multiple sizes. To test is a new rule is added tests-malloc-hugetlb1, which run the addes tests with the required GLIBC_TUNABLE setting. Checked on x86_64-linux-gnu. Reviewed-by: DJ Delorie <dj@redhat.com>
* Use LFS and 64 bit time for installed programs (BZ #15333)Adhemerval Zanella2021-12-151-2/+2
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The installed programs are built with a combination of different values for MODULE_NAME, as below. To enable both Long File Support and 64 bt time, -D_TIME_BITS=64 -D_FILE_OFFSET_BITS=64 is added for nonlibi, nscd, lddlibc4, libresolv, ldconfig, locale_programs, iconvprogs, libnss_files, libnss_compat, libnss_db, libnss_hesiod, libutil, libpcprofile, and libSegFault. nscd/nscd nscd/nscd.o MODULE_NAME=nscd nscd/connections.o MODULE_NAME=nscd nscd/pwdcache.o MODULE_NAME=nscd nscd/getpwnam_r.o MODULE_NAME=nscd nscd/getpwuid_r.o MODULE_NAME=nscd nscd/grpcache.o MODULE_NAME=nscd nscd/getgrnam_r.o MODULE_NAME=nscd nscd/getgrgid_r.o MODULE_NAME=nscd nscd/hstcache.o MODULE_NAME=nscd nscd/gethstbyad_r.o MODULE_NAME=nscd nscd/gethstbynm3_r.o MODULE_NAME=nscd nscd/getsrvbynm_r.o MODULE_NAME=nscd nscd/getsrvbypt_r.o MODULE_NAME=nscd nscd/servicescache.o MODULE_NAME=nscd nscd/dbg_log.o MODULE_NAME=nscd nscd/nscd_conf.o MODULE_NAME=nscd nscd/nscd_stat.o MODULE_NAME=nscd nscd/cache.o MODULE_NAME=nscd nscd/mem.o MODULE_NAME=nscd nscd/nscd_setup_thread.o MODULE_NAME=nscd nscd/xmalloc.o MODULE_NAME=nscd nscd/xstrdup.o MODULE_NAME=nscd nscd/aicache.o MODULE_NAME=nscd nscd/initgrcache.o MODULE_NAME=nscd nscd/gai.o MODULE_NAME=nscd nscd/res_hconf.o MODULE_NAME=nscd nscd/netgroupcache.o MODULE_NAME=nscd nscd/cachedumper.o MODULE_NAME=nscd elf/lddlibc4 elf/lddlibc4 MODULE_NAME=lddlibc4 elf/pldd elf/pldd.o MODULE_NAME=nonlib elf/xmalloc.o MODULE_NAME=nonlib elf/sln elf/sln.o MODULE_NAME=nonlib elf/static-stubs.o MODULE_NAME=nonlib elf/sprof MODULE_NAME=nonlib elf/ldconfig elf/ldconfig.o MODULE_NAME=ldconfig elf/cache.o MODULE_NAME=nonlib elf/readlib.o MODULE_NAME=nonlib elf/xmalloc.o MODULE_NAME=nonlib elf/xstrdup.o MODULE_NAME=nonlib elf/chroot_canon.o MODULE_NAME=nonlib elf/static-stubs.o MODULE_NAME=nonlib elf/stringtable.o MODULE_NAME=nonlib io/pwd io/pwd.o MODULE_NAME=nonlib locale/locale locale/locale.o MODULE_NAME=locale_programs locale/locale-spec.o MODULE_NAME=locale_programs locale/charmap-dir.o MODULE_NAME=locale_programs locale/simple-hash.o MODULE_NAME=locale_programs locale/xmalloc.o MODULE_NAME=locale_programs locale/xstrdup.o MODULE_NAME=locale_programs locale/record-status.o MODULE_NAME=locale_programs locale/xasprintf.o MODULE_NAME=locale_programs locale/localedef locale/localedef.o MODULE_NAME=locale_programs locale/ld-ctype.o MODULE_NAME=locale_programs locale/ld-messages.o MODULE_NAME=locale_programs locale/ld-monetary.o MODULE_NAME=locale_programs locale/ld-numeric.o MODULE_NAME=locale_programs locale/ld-time.o MODULE_NAME=locale_programs locale/ld-paper.o MODULE_NAME=locale_programs locale/ld-name.o MODULE_NAME=locale_programs locale/ld-address.o MODULE_NAME=locale_programs locale/ld-telephone.o MODULE_NAME=locale_programs locale/ld-measurement.o MODULE_NAME=locale_programs locale/ld-identification.o MODULE_NAME=locale_programs locale/ld-collate.o MODULE_NAME=locale_programs locale/charmap.o MODULE_NAME=locale_programs locale/linereader.o MODULE_NAME=locale_programs locale/locfile.o MODULE_NAME=locale_programs locale/repertoire.o MODULE_NAME=locale_programs locale/locarchive.o MODULE_NAME=locale_programs locale/md5.o MODULE_NAME=locale_programs locale/charmap-dir.o MODULE_NAME=locale_programs locale/simple-hash.o MODULE_NAME=locale_programs locale/xmalloc.o MODULE_NAME=locale_programs locale/xstrdup.o MODULE_NAME=locale_programs locale/record-status.o MODULE_NAME=locale_programs locale/xasprintf.o MODULE_NAME=locale_programs catgets/gencat catgets/gencat.o MODULE_NAME=nonlib catgets/xmalloc.o MODULE_NAME=nonlib nss/makedb nss/makedb.o MODULE_NAME=nonlib nss/xmalloc.o MODULE_NAME=nonlib nss/hash-string.o MODULE_NAME=nonlib nss/getent nss/getent.o MODULE_NAME=nonlib posix/getconf posix/getconf.o MODULE_NAME=nonlib login/utmpdump login/utmpdump.o MODULE_NAME=nonlib debug/pcprofiledump debug/pcprofiledump.o MODULE_NAME=nonlib timezone/zic timezone/zic.o MODULE_NAME=nonlib timezone/zdump timezone/zdump.o MODULE_NAME=nonlib iconv/iconv_prog iconv/iconv_prog.o MODULE_NAME=nonlib iconv/iconv_charmap.o MODULE_NAME=iconvprogs iconv/charmap.o MODULE_NAME=iconvprogs iconv/charmap-dir.o MODULE_NAME=iconvprogs iconv/linereader.o MODULE_NAME=iconvprogs iconv/dummy-repertoire.o MODULE_NAME=iconvprogs iconv/simple-hash.o MODULE_NAME=iconvprogs iconv/xstrdup.o MODULE_NAME=iconvprogs iconv/xmalloc.o MODULE_NAME=iconvprogs iconv/record-status.o MODULE_NAME=iconvprogs iconv/iconvconfig iconv/iconvconfig.o MODULE_NAME=nonlib iconv/strtab.o MODULE_NAME=iconvprogs iconv/xmalloc.o MODULE_NAME=iconvprogs iconv/hash-string.o MODULE_NAME=iconvprogs nss/libnss_files.so MODULE_NAME=libnss_files nss/libnss_compat.so.2 MODULE_NAME=libnss_compat nss/libnss_db.so MODULE_NAME=libnss_db hesiod/libnss_hesiod.so MODULE_NAME=libnss_hesiod login/libutil.so MODULE_NAME=libutil debug/libpcprofile.so MODULE_NAME=libpcprofile debug/libSegFault.so MODULE_NAME=libSegFault Also, to avoid adding both LFS and 64 bit time support on internal tests they are moved to a newer 'testsuite-internal' module. It should be similar to 'nonlib' regarding internal definition and linking namespace. This patch also enables LFS and 64 bit support of libsupport container programs (echo-container, test-container, shell-container, and true-container). Checked on x86_64-linux-gnu and i686-linux-gnu. Reviewed-by: DJ Delorie <dj@redhat.com>
* Support target specific ALIGN for variable alignment test [BZ #28676]H.J. Lu2021-12-142-6/+2
| | | | | | | | | | | Add <tst-file-align.h> to support target specific ALIGN for variable alignment test: 1. Alpha: Use 0x10000. 2. MicroBlaze and Nios II: Use 0x8000. 3. All others: Use 0x200000. Reviewed-by: Adhemerval Zanella <adhemerval.zanella@linaro.org>
* elf: Align argument of __munmap to page size [BZ #28676]H.J. Lu2021-12-141-0/+1
| | | | | | | | | | | | On Linux/x86-64, for elf/tst-align3, we now get munmap(0x7f88f9401000, 1126424) = 0 instead of munmap(0x7f1615200018, 544768) = -1 EINVAL (Invalid argument) Reviewed-by: Florian Weimer <fweimer@redhat.com>
* elf: Use new dependency sorting algorithm by defaultFlorian Weimer2021-12-142-2/+2
| | | | | | | The default has to change eventually, and there are no known failures that require a delay. Reviewed-by: Adhemerval Zanella <adhemerval.zanella@linaro.org>
* elf: Use errcode instead of (unset) errno in rtld_chain_loadFlorian Weimer2021-12-101-1/+1
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* Add a testcase to check alignment of PT_LOAD segment [BZ #28676]H.J. Lu2021-12-103-2/+82
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* elf: Properly align PT_LOAD segments [BZ #28676]Rongwei Wang2021-12-103-5/+50
| | | | | | | | | | | When PT_LOAD segment alignment > the page size, allocate enough space to ensure that the segment can be properly aligned. This change helps code segments use huge pages become simple and available. This fixes [BZ #28676]. Signed-off-by: Xu Yu <xuyu@linux.alibaba.com> Signed-off-by: Rongwei Wang <rongwei.wang@linux.alibaba.com>
* elf: Install a symbolic link to ld.so as /usr/bin/ld.soFlorian Weimer2021-12-101-1/+6
| | | | | | | | This makes ld.so features such as --preload, --audit, and --list-diagnostics more accessible to end users because they do not need to know the ABI name of the dynamic loader. Reviewed-by: Carlos O'Donell <carlos@redhat.com>
* 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: execve statically linked programs instead of crashing [BZ #28648]Florian Weimer2021-12-053-8/+107
| | | | | | | | | | | | | | | Programs without dynamic dependencies and without a program interpreter are now run via execve. Previously, the dynamic linker either crashed while attempting to read a non-existing dynamic segment (looking for DT_AUDIT/DT_DEPAUDIT data), or the self-relocated in the static PIE executable crashed because the outer dynamic linker had already applied RELRO protection. <dl-execve.h> is needed because execve is not available in the dynamic loader on Hurd. Reviewed-by: H.J. Lu <hjl.tools@gmail.com>
* elf: add definition for ELF_NOTE_FDO and NT_FDO_PACKAGING_METADATA noteLuca Boccassi2021-12-021-0/+6
| | | | | | | As defined on: https://systemd.io/COREDUMP_PACKAGE_METADATA/ this note will be used starting from Fedora 36. Signed-off-by: Luca Boccassi <bluca@debian.org>
* elf: Include <stdbool.h> in tst-tls20.cFlorian Weimer2021-11-301-0/+1
| | | | The test uses the bool type.
* elf: Include <stdint.h> in tst-tls20.cFlorian Weimer2021-11-301-0/+1
| | | | The test uses standard integer types.
* elf: Move la_activity (LA_ACT_ADD) after _dl_add_to_namespace_list() (BZ #28062)Adhemerval Zanella2021-11-185-37/+271
| | | | | | | | It ensures that the the namespace is guaranteed to not be empty. Checked on x86_64-linux-gnu. Reviewed-by: Florian Weimer <fweimer@redhat.com>
* elf: Introduce GLRO (dl_libc_freeres), called from __libc_freeresFlorian Weimer2021-11-173-1/+26
| | | | | | | This will be used to deallocate memory allocated using the non-minimal malloc. Reviewed-by: Adhemerval Zanella <adhemerval.zanella@linaro.org>
* elf: hidden visibility for __minimal_malloc functionsAdhemerval Zanella2021-11-161-0/+5
| | | | | | | | Since b05fae4d8e34, __minimal malloc code is used during static startup before PIE self-relocation (_dl_relocate_static_pie). So it requires the same fix done for other objects by 47618209d05a. Checked on aarch64, x86_64, and i686 with and without static-pie.
* elf: Use a temporary file to generate Makefile fragments [BZ #28550]H.J. Lu2021-11-161-2/+8
| | | | | | | | | | | | 1. Use a temporary file to generate Makefile fragments for DSO sorting tests and use -include on them. 2. Add Makefile fragments to postclean-generated so that a "make clean" removes the autogenerated fragments and a subsequent "make" regenerates them. This partially fixes BZ #28550. Reviewed-by: Adhemerval Zanella <adhemerval.zanella@linaro.org>
* elf: Move LAV_CURRENT to link_lavcurrent.hAdhemerval Zanella2021-11-152-2/+2
| | | | No functional change.
* Fix build a chec failures after b05fae4d8e34Adhemerval Zanella2021-11-091-0/+2
| | | | | | | | | | The include cleanup on dl-minimal.c removed too much for some targets. Also for Hurd, __sbrk is removed from localplt.data now that tunables allocated memory through mmap. Checked with a build for all affected architectures.
* elf: Use the minimal malloc on tunables_strdupAdhemerval Zanella2021-11-094-119/+129
| | | | | | | | | | | | | | | | | | | | The rtld_malloc functions are moved to its own file so it can be used on csu code. Also, the functiosn are renamed to __minimal_* (since there are now used not only on loader code). Using the __minimal_malloc on tunables_strdup() avoids potential issues with sbrk() calls while processing the tunables (I see sporadic elf/tst-dso-ordering9 on powerpc64le with different tests failing due ASLR). Also, using __minimal_malloc over plain mmap optimizes the memory allocation on both static and dynamic case (since it will any unused space in either the last page of data segments, avoiding mmap() call, or from the previous mmap() call). Checked on x86_64-linux-gnu, i686-linux-gnu, and powerpc64le-linux-gnu. Reviewed-by: Siddhesh Poyarekar <siddhesh@sourceware.org>
* elf: Earlier missing dynamic segment check in _dl_map_object_from_fdFlorian Weimer2021-11-051-10/+12
| | | | | | | | | Separated debuginfo files have PT_DYNAMIC with p_filesz == 0. We need to check for that before the _dl_map_segments call because that could attempt to write to mappings that extend beyond the end of the file, resulting in SIGBUS. Reviewed-by: H.J. Lu <hjl.tools@gmail.com>
* elf: Do not run DSO sorting if tunables is not enabledAdhemerval Zanella2021-11-031-0/+2
| | | | | | Since the argorithm selection requires tunables. Checked on x86_64-linux-gnu with --enable-tunables=no.
* 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>