mapped from a static executable.
On targets that support different page sizes, the kernel communicates
- the size currently in use via the auxiliary vector. This vector is
- available to initial startup, but not any DSOs loaded later on. As
- static executables do not export their symbols a DSO cannot access
- the value obtained by initial startup and the value therefore has to
- be passed on to the DSO and stored within its data area explicitly.
- This is performed by a call to DL_STATIC_INIT that is defined in a
- target-dependent way, and that on variable page size targets stores
- it in the GLRO(dl_pagesize) variable of the DSO's dynamic linker. */
+ the size currently in use via the auxiliary vector. The auxiliary
+ vector and HWCAP/HWCAP2 bits are copied across the static dlopen
+ boundary in __rtld_static_init. */
static int
do_test (void)
{
routines = $(all-dl-routines) dl-support dl-iteratephdr \
dl-addr dl-addr-obj enbl-secure dl-profstub \
dl-origin dl-libc dl-sym dl-sysdep dl-error \
- dl-reloc-static-pie libc_early_init
+ dl-reloc-static-pie libc_early_init rtld_static_init
# The core dynamic linking functions are in libc for the static and
# profiled libraries.
# But they are absent from the shared libc, because that code is in ld.so.
elide-routines.os = $(all-dl-routines) dl-support enbl-secure dl-origin \
dl-sysdep dl-exception dl-reloc-static-pie \
- thread_gscope_wait
+ thread_gscope_wait rtld_static_init
# ld.so uses those routines, plus some special stuff for being the program
# interpreter and operating independent of libc.
tst-tlsalign-static tst-tlsalign-extern-static \
tst-linkall-static tst-env-setuid tst-env-setuid-tunables \
tst-single_threaded-static tst-single_threaded-pthread-static \
- tst-dst-static
+ tst-dst-static tst-getauxval-static
tests-static-internal := tst-tls1-static tst-tls2-static \
tst-ptrguard1-static tst-stackguard1-static \
libmarkermod3-1 libmarkermod3-2 libmarkermod3-3 \
libmarkermod4-1 libmarkermod4-2 libmarkermod4-3 libmarkermod4-4 \
tst-tls20mod-bad tst-tls21mod tst-dlmopen-dlerror-mod \
+ tst-auxvalmod \
# Most modules build with _ISOMAC defined, but those filtered out
# depend on internal headers.
$(objpfx)tst-tls21: $(libdl) $(shared-thread-library)
$(objpfx)tst-tls21.out: $(objpfx)tst-tls21mod.so
$(objpfx)tst-tls21mod.so: $(tst-tls-many-dynamic-modules:%=$(objpfx)%.so)
+
+$(objpfx)tst-getauxval-static: $(common-objpfx)dlfcn/libdl.a
+$(objpfx)tst-getauxval-static.out: $(objpfx)tst-auxvalmod.so
+tst-getauxval-static-ENV = LD_LIBRARY_PATH=$(objpfx):$(common-objpfx)
#include <libc-internal.h>
#include <array_length.h>
#include <libc-early-init.h>
+#include <gnu/lib-names.h>
#include <dl-dst.h>
#include <dl-prop.h>
/* So far, so good. Now check the versions. */
for (unsigned int i = 0; i < new->l_searchlist.r_nlist; ++i)
if (new->l_searchlist.r_list[i]->l_real->l_versions == NULL)
- (void) _dl_check_map_versions (new->l_searchlist.r_list[i]->l_real,
- 0, 0);
+ {
+ struct link_map *map = new->l_searchlist.r_list[i]->l_real;
+ _dl_check_map_versions (map, 0, 0);
+#ifndef SHARED
+ /* During static dlopen, check if ld.so has been loaded.
+ Perform partial initialization in this case. This must
+ come after the symbol versioning initialization in
+ _dl_check_map_versions. */
+ if (map->l_info[DT_SONAME] != NULL
+ && strcmp (((const char *) D_PTR (map, l_info[DT_STRTAB])
+ + map->l_info[DT_SONAME]->d_un.d_val), LD_SO) == 0)
+ __rtld_static_init (map);
+#endif
+ }
#ifdef SHARED
/* Auditing checkpoint: we have added all objects. */
--- /dev/null
+/* Partial initialization of ld.so loaded via static dlopen.
+ Copyright (C) 2021 Free Software Foundation, Inc.
+ This file is part of the GNU C Library.
+
+ The GNU C Library is free software; you can redistribute it and/or
+ modify it under the terms of the GNU Lesser General Public
+ License as published by the Free Software Foundation; either
+ version 2.1 of the License, or (at your option) any later version.
+
+ The GNU C Library is distributed in the hope that it will be useful,
+ but WITHOUT ANY WARRANTY; without even the implied warranty of
+ MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+ Lesser General Public License for more details.
+
+ You should have received a copy of the GNU Lesser General Public
+ License along with the GNU C Library; if not, see
+ <https://www.gnu.org/licenses/>. */
+
+#include <assert.h>
+
+/* Very special case: This object is built into the static libc, but
+ must know the layout of _rtld_global_ro. */
+#define SHARED
+#include <ldsodefs.h>
+
+#include <rtld_static_init.h>
+
+void
+__rtld_static_init (struct link_map *map)
+{
+ const ElfW(Sym) *sym
+ = _dl_lookup_direct (map, "_rtld_global_ro",
+ 0x9f28436a, /* dl_new_hash output. */
+ "GLIBC_PRIVATE",
+ 0x0963cf85); /* _dl_elf_hash output. */
+ assert (sym != NULL);
+ struct rtld_global_ro *dl = DL_SYMBOL_ADDRESS (map, sym);
+
+ /* Perform partial initialization here. Note that this runs before
+ ld.so is relocated, so only members initialized without
+ relocations can be written here. */
+#ifdef HAVE_AUX_VECTOR
+ extern __typeof (dl->_dl_auxv) _dl_auxv attribute_hidden;
+ dl->_dl_auxv = _dl_auxv;
+ extern __typeof (dl->_dl_clktck) _dl_clktck attribute_hidden;
+ dl->_dl_clktck = _dl_clktck;
+#endif
+ extern __typeof (dl->_dl_hwcap) _dl_hwcap attribute_hidden;
+ dl->_dl_hwcap = _dl_hwcap;
+ extern __typeof (dl->_dl_hwcap2) _dl_hwcap2 attribute_hidden;
+ dl->_dl_hwcap2 = _dl_hwcap2;
+ extern __typeof (dl->_dl_pagesize) _dl_pagesize attribute_hidden;
+ dl->_dl_pagesize = _dl_pagesize;
+
+ __rtld_static_init_arch (map, dl);
+}
--- /dev/null
+/* Wrapper for getauxval testing.
+ Copyright (C) 2021 Free Software Foundation, Inc.
+ This file is part of the GNU C Library.
+
+ The GNU C Library is free software; you can redistribute it and/or
+ modify it under the terms of the GNU Lesser General Public
+ License as published by the Free Software Foundation; either
+ version 2.1 of the License, or (at your option) any later version.
+
+ The GNU C Library is distributed in the hope that it will be useful,
+ but WITHOUT ANY WARRANTY; without even the implied warranty of
+ MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+ Lesser General Public License for more details.
+
+ You should have received a copy of the GNU Lesser General Public
+ License along with the GNU C Library; if not, see
+ <https://www.gnu.org/licenses/>. */
+
+#include <errno.h>
+#include <sys/auxv.h>
+
+unsigned long
+getauxval_wrapper (unsigned long type, int *errnop)
+{
+ errno = *errnop;
+ unsigned long result = getauxval (type);
+ *errnop = errno;
+ return result;
+}
--- /dev/null
+/* Test getauxval from a dynamic library after static dlopen.
+ Copyright (C) 2021 Free Software Foundation, Inc.
+ This file is part of the GNU C Library.
+
+ The GNU C Library is free software; you can redistribute it and/or
+ modify it under the terms of the GNU Lesser General Public
+ License as published by the Free Software Foundation; either
+ version 2.1 of the License, or (at your option) any later version.
+
+ The GNU C Library is distributed in the hope that it will be useful,
+ but WITHOUT ANY WARRANTY; without even the implied warranty of
+ MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+ Lesser General Public License for more details.
+
+ You should have received a copy of the GNU Lesser General Public
+ License along with the GNU C Library; if not, see
+ <https://www.gnu.org/licenses/>. */
+
+#include <dlfcn.h>
+#include <errno.h>
+#include <stdio.h>
+#include <support/check.h>
+#include <support/xdlfcn.h>
+#include <sys/auxv.h>
+
+unsigned long getauxval_wrapper (unsigned long type, int *errnop);
+
+static int
+do_test (void)
+{
+ unsigned long outer_random = getauxval (AT_RANDOM);
+ if (outer_random == 0)
+ FAIL_UNSUPPORTED ("getauxval does not support AT_RANDOM");
+
+ unsigned long missing_auxv_type;
+ for (missing_auxv_type = AT_RANDOM + 1; ; ++missing_auxv_type)
+ {
+ errno = 0;
+ if (getauxval (missing_auxv_type) == 0 && errno != 0)
+ {
+ TEST_COMPARE (errno, ENOENT);
+ break;
+ }
+ }
+ printf ("info: first missing type: %lu\n", missing_auxv_type);
+
+ void *handle = xdlopen ("tst-auxvalmod.so", RTLD_LAZY);
+ void *ptr = xdlsym (handle, "getauxval_wrapper");
+
+ __typeof__ (getauxval_wrapper) *wrapper = ptr;
+ int inner_errno = 0;
+ unsigned long inner_random = wrapper (AT_RANDOM, &inner_errno);
+ TEST_COMPARE (outer_random, inner_random);
+
+ inner_errno = 0;
+ TEST_COMPARE (wrapper (missing_auxv_type, &inner_errno), 0);
+ TEST_COMPARE (inner_errno, ENOENT);
+
+ TEST_COMPARE (getauxval (AT_HWCAP), wrapper (AT_HWCAP, &inner_errno));
+ TEST_COMPARE (getauxval (AT_HWCAP2), wrapper (AT_HWCAP2, &inner_errno));
+
+ xdlclose (handle);
+ return 0;
+}
+
+#include <support/test-driver.c>
#endif
}
+#ifndef SHARED
+/* Called before relocating ld.so during static dlopen. This can be
+ used to partly initialize the dormant ld.so copy in the static
+ dlopen namespace. */
+void __rtld_static_init (struct link_map *map) attribute_hidden;
+#endif
+
/* Return true if the ld.so copy in this namespace is actually active
and working. If false, the dl_open/dlfcn hooks have to be used to
call into the outer dynamic linker (which happens after static
--- /dev/null
+/* Partial initialization of ld.so loaded via static dlopen. Generic helper.
+ Copyright (C) 2021 Free Software Foundation, Inc.
+ This file is part of the GNU C Library.
+
+ The GNU C Library is free software; you can redistribute it and/or
+ modify it under the terms of the GNU Lesser General Public
+ License as published by the Free Software Foundation; either
+ version 2.1 of the License, or (at your option) any later version.
+
+ The GNU C Library is distributed in the hope that it will be useful,
+ but WITHOUT ANY WARRANTY; without even the implied warranty of
+ MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+ Lesser General Public License for more details.
+
+ You should have received a copy of the GNU Lesser General Public
+ License along with the GNU C Library; if not, see
+ <https://www.gnu.org/licenses/>. */
+
+static inline void
+__rtld_static_init_arch (struct link_map *map, struct rtld_global_ro *dl)
+{
+ /* The generic helper does not perform any additional
+ initialization. */
+}
git://sourceware.org / glibc.git / commitdiff