diff options
| -rw-r--r-- | dlfcn/tststatic5.c | 11 | ||||
| -rw-r--r-- | elf/Makefile | 11 | ||||
| -rw-r--r-- | elf/dl-open.c | 17 | ||||
| -rw-r--r-- | elf/rtld_static_init.c | 56 | ||||
| -rw-r--r-- | elf/tst-auxvalmod.c | 29 | ||||
| -rw-r--r-- | elf/tst-getauxval-static.c | 66 | ||||
| -rw-r--r-- | sysdeps/generic/ldsodefs.h | 7 | ||||
| -rw-r--r-- | sysdeps/generic/rtld_static_init.h | 24 |
8 files changed, 208 insertions, 13 deletions
diff --git a/dlfcn/tststatic5.c b/dlfcn/tststatic5.c index 872e87fbaf..e0a50b7dcc 100644 --- a/dlfcn/tststatic5.c +++ b/dlfcn/tststatic5.c @@ -25,14 +25,9 @@ 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) { diff --git a/elf/Makefile b/elf/Makefile index 4e148e532a..5e809dbfaa 100644 --- a/elf/Makefile +++ b/elf/Makefile @@ -25,7 +25,7 @@ headers = elf.h bits/elfclass.h link.h bits/link.h 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. @@ -60,7 +60,7 @@ all-dl-routines = $(dl-routines) $(sysdep-dl-routines) # 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. @@ -161,7 +161,7 @@ tests-static-normal := tst-leaks1-static tst-array1-static tst-array5-static \ 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 \ @@ -346,6 +346,7 @@ modules-names = testobj1 testobj2 testobj3 testobj4 testobj5 testobj6 \ 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. @@ -1942,3 +1943,7 @@ $(objpfx)tst-tls20.out: $(objpfx)tst-tls20mod-bad.so \ $(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) diff --git a/elf/dl-open.c b/elf/dl-open.c index 0887fc5cc5..c2ac5ee94f 100644 --- a/elf/dl-open.c +++ b/elf/dl-open.c @@ -35,6 +35,7 @@ #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> @@ -590,8 +591,20 @@ dl_open_worker (void *a) /* 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. */ diff --git a/elf/rtld_static_init.c b/elf/rtld_static_init.c new file mode 100644 index 0000000000..cd823096d6 --- /dev/null +++ b/elf/rtld_static_init.c @@ -0,0 +1,56 @@ +/* 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); +} diff --git a/elf/tst-auxvalmod.c b/elf/tst-auxvalmod.c new file mode 100644 index 0000000000..f87cf98438 --- /dev/null +++ b/elf/tst-auxvalmod.c @@ -0,0 +1,29 @@ +/* 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; +} diff --git a/elf/tst-getauxval-static.c b/elf/tst-getauxval-static.c new file mode 100644 index 0000000000..8bc870709a --- /dev/null +++ b/elf/tst-getauxval-static.c @@ -0,0 +1,66 @@ +/* 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> diff --git a/sysdeps/generic/ldsodefs.h b/sysdeps/generic/ldsodefs.h index 8426b5cbd8..e43d6f5ecd 100644 --- a/sysdeps/generic/ldsodefs.h +++ b/sysdeps/generic/ldsodefs.h @@ -1313,6 +1313,13 @@ dl_init_static_tls (struct link_map *map) #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 diff --git a/sysdeps/generic/rtld_static_init.h b/sysdeps/generic/rtld_static_init.h new file mode 100644 index 0000000000..3f8dde22a8 --- /dev/null +++ b/sysdeps/generic/rtld_static_init.h @@ -0,0 +1,24 @@ +/* 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. */ +} |