From 365624e2d2a342cdb693b4cc35d2312169959e28 Mon Sep 17 00:00:00 2001 From: Florian Weimer Date: Fri, 13 Dec 2019 10:18:24 +0100 Subject: dlopen: Fix issues related to NODELETE handling and relocations The assumption behind the assert in activate_nodelete was wrong: Inconsistency detected by ld.so: dl-open.c: 459: activate_nodelete: Assertion `!imap->l_init_called || imap->l_type != lt_loaded' failed! (edit) It can happen that an already-loaded object that is in the local scope is promoted to NODELETE status, via binding to a unique symbol. Similarly, it is possible that such NODELETE promotion occurs to an already-loaded object from the global scope. This is why the loop in activate_nodelete has to cover all objects in the namespace of the new object. In do_lookup_unique, it could happen that the NODELETE status of an already-loaded object was overwritten with a pending NODELETE status. As a result, if dlopen fails, this could cause a loss of the NODELETE status of the affected object, eventually resulting in an incorrect unload. Fixes commit f63b73814f74032c0e5d0a83300e3d864ef905e5 ("Remove all loaded objects if dlopen fails, ignoring NODELETE [BZ #20839]"). --- elf/Makefile | 66 +++++++++++- elf/dl-lookup.c | 6 +- elf/dl-open.c | 41 +++----- elf/tst-dlopen-nodelete-reloc-mod1.c | 39 +++++++ elf/tst-dlopen-nodelete-reloc-mod10.c | 41 ++++++++ elf/tst-dlopen-nodelete-reloc-mod11.cc | 49 +++++++++ elf/tst-dlopen-nodelete-reloc-mod12.cc | 42 ++++++++ elf/tst-dlopen-nodelete-reloc-mod13.cc | 48 +++++++++ elf/tst-dlopen-nodelete-reloc-mod13.h | 24 +++++ elf/tst-dlopen-nodelete-reloc-mod14.cc | 42 ++++++++ elf/tst-dlopen-nodelete-reloc-mod15.cc | 42 ++++++++ elf/tst-dlopen-nodelete-reloc-mod16.c | 27 +++++ elf/tst-dlopen-nodelete-reloc-mod17.c | 19 ++++ elf/tst-dlopen-nodelete-reloc-mod2.c | 38 +++++++ elf/tst-dlopen-nodelete-reloc-mod3.c | 38 +++++++ elf/tst-dlopen-nodelete-reloc-mod4.c | 37 +++++++ elf/tst-dlopen-nodelete-reloc-mod5.c | 38 +++++++ elf/tst-dlopen-nodelete-reloc-mod6.cc | 42 ++++++++ elf/tst-dlopen-nodelete-reloc-mod7.cc | 48 +++++++++ elf/tst-dlopen-nodelete-reloc-mod8.c | 41 ++++++++ elf/tst-dlopen-nodelete-reloc-mod9.cc | 42 ++++++++ elf/tst-dlopen-nodelete-reloc.c | 179 +++++++++++++++++++++++++++++++++ elf/tst-dlopen-nodelete-reloc.h | 35 +++++++ 23 files changed, 992 insertions(+), 32 deletions(-) create mode 100644 elf/tst-dlopen-nodelete-reloc-mod1.c create mode 100644 elf/tst-dlopen-nodelete-reloc-mod10.c create mode 100644 elf/tst-dlopen-nodelete-reloc-mod11.cc create mode 100644 elf/tst-dlopen-nodelete-reloc-mod12.cc create mode 100644 elf/tst-dlopen-nodelete-reloc-mod13.cc create mode 100644 elf/tst-dlopen-nodelete-reloc-mod13.h create mode 100644 elf/tst-dlopen-nodelete-reloc-mod14.cc create mode 100644 elf/tst-dlopen-nodelete-reloc-mod15.cc create mode 100644 elf/tst-dlopen-nodelete-reloc-mod16.c create mode 100644 elf/tst-dlopen-nodelete-reloc-mod17.c create mode 100644 elf/tst-dlopen-nodelete-reloc-mod2.c create mode 100644 elf/tst-dlopen-nodelete-reloc-mod3.c create mode 100644 elf/tst-dlopen-nodelete-reloc-mod4.c create mode 100644 elf/tst-dlopen-nodelete-reloc-mod5.c create mode 100644 elf/tst-dlopen-nodelete-reloc-mod6.cc create mode 100644 elf/tst-dlopen-nodelete-reloc-mod7.cc create mode 100644 elf/tst-dlopen-nodelete-reloc-mod8.c create mode 100644 elf/tst-dlopen-nodelete-reloc-mod9.cc create mode 100644 elf/tst-dlopen-nodelete-reloc.c create mode 100644 elf/tst-dlopen-nodelete-reloc.h diff --git a/elf/Makefile b/elf/Makefile index b2b3be203f..72a5aa88b1 100644 --- a/elf/Makefile +++ b/elf/Makefile @@ -191,7 +191,7 @@ tests += restest1 preloadtest loadfail multiload origtest resolvfail \ tst-audit1 tst-audit2 tst-audit8 tst-audit9 \ tst-addr1 tst-thrlock \ tst-unique1 tst-unique2 $(if $(CXX),tst-unique3 tst-unique4 \ - tst-nodelete) \ + tst-nodelete tst-dlopen-nodelete-reloc) \ tst-initorder tst-initorder2 tst-relsort1 tst-null-argv \ tst-tlsalign tst-tlsalign-extern tst-nodelete-opened \ tst-nodelete2 tst-audit11 tst-audit12 tst-dlsym-error tst-noload \ @@ -271,7 +271,24 @@ modules-names = testobj1 testobj2 testobj3 testobj4 testobj5 testobj6 \ tst-auditmod9a tst-auditmod9b \ $(if $(CXX),tst-unique3lib tst-unique3lib2 tst-unique4lib \ tst-nodelete-uniquemod tst-nodelete-rtldmod \ - tst-nodelete-zmod) \ + tst-nodelete-zmod \ + tst-dlopen-nodelete-reloc-mod1 \ + tst-dlopen-nodelete-reloc-mod2 \ + tst-dlopen-nodelete-reloc-mod3 \ + tst-dlopen-nodelete-reloc-mod4 \ + tst-dlopen-nodelete-reloc-mod5 \ + tst-dlopen-nodelete-reloc-mod6 \ + tst-dlopen-nodelete-reloc-mod7 \ + tst-dlopen-nodelete-reloc-mod8 \ + tst-dlopen-nodelete-reloc-mod9 \ + tst-dlopen-nodelete-reloc-mod10 \ + tst-dlopen-nodelete-reloc-mod11 \ + tst-dlopen-nodelete-reloc-mod12 \ + tst-dlopen-nodelete-reloc-mod13 \ + tst-dlopen-nodelete-reloc-mod14 \ + tst-dlopen-nodelete-reloc-mod15 \ + tst-dlopen-nodelete-reloc-mod16 \ + tst-dlopen-nodelete-reloc-mod17) \ tst-initordera1 tst-initorderb1 \ tst-initordera2 tst-initorderb2 \ tst-initordera3 tst-initordera4 \ @@ -1627,3 +1644,48 @@ $(objpfx)tst-dlopenfailmod1.so: \ $(shared-thread-library) $(objpfx)tst-dlopenfaillinkmod.so LDFLAGS-tst-dlopenfaillinkmod.so = -Wl,-soname,tst-dlopenfail-missingmod.so $(objpfx)tst-dlopenfailmod2.so: $(shared-thread-library) + +$(objpfx)tst-dlopen-nodelete-reloc: $(libdl) +$(objpfx)tst-dlopen-nodelete-reloc.out: \ + $(objpfx)tst-dlopen-nodelete-reloc-mod1.so \ + $(objpfx)tst-dlopen-nodelete-reloc-mod2.so \ + $(objpfx)tst-dlopen-nodelete-reloc-mod3.so \ + $(objpfx)tst-dlopen-nodelete-reloc-mod4.so \ + $(objpfx)tst-dlopen-nodelete-reloc-mod5.so \ + $(objpfx)tst-dlopen-nodelete-reloc-mod6.so \ + $(objpfx)tst-dlopen-nodelete-reloc-mod7.so \ + $(objpfx)tst-dlopen-nodelete-reloc-mod8.so \ + $(objpfx)tst-dlopen-nodelete-reloc-mod9.so \ + $(objpfx)tst-dlopen-nodelete-reloc-mod10.so \ + $(objpfx)tst-dlopen-nodelete-reloc-mod11.so \ + $(objpfx)tst-dlopen-nodelete-reloc-mod12.so \ + $(objpfx)tst-dlopen-nodelete-reloc-mod13.so \ + $(objpfx)tst-dlopen-nodelete-reloc-mod14.so \ + $(objpfx)tst-dlopen-nodelete-reloc-mod15.so \ + $(objpfx)tst-dlopen-nodelete-reloc-mod16.so \ + $(objpfx)tst-dlopen-nodelete-reloc-mod17.so +tst-dlopen-nodelete-reloc-mod2.so-no-z-defs = yes +LDFLAGS-tst-dlopen-nodelete-reloc-mod2.so = -Wl,-z,nodelete +$(objpfx)tst-dlopen-nodelete-reloc-mod4.so: \ + $(objpfx)tst-dlopen-nodelete-reloc-mod3.so +LDFLAGS-tst-dlopen-nodelete-reloc-mod4.so = -Wl,--no-as-needed +$(objpfx)tst-dlopen-nodelete-reloc-mod5.so: \ + $(objpfx)tst-dlopen-nodelete-reloc-mod4.so +LDFLAGS-tst-dlopen-nodelete-reloc-mod5.so = -Wl,-z,nodelete,--no-as-needed +tst-dlopen-nodelete-reloc-mod5.so-no-z-defs = yes +tst-dlopen-nodelete-reloc-mod7.so-no-z-defs = yes +$(objpfx)tst-dlopen-nodelete-reloc-mod8.so: $(libdl) +$(objpfx)tst-dlopen-nodelete-reloc-mod10.so: $(libdl) +tst-dlopen-nodelete-reloc-mod11.so-no-z-defs = yes +$(objpfx)tst-dlopen-nodelete-reloc-mod13.so: \ + $(objpfx)tst-dlopen-nodelete-reloc-mod12.so +$(objpfx)tst-dlopen-nodelete-reloc-mod15.so: \ + $(objpfx)tst-dlopen-nodelete-reloc-mod14.so +tst-dlopen-nodelete-reloc-mod16.so-no-z-defs = yes +$(objpfx)tst-dlopen-nodelete-reloc-mod16.so: \ + $(objpfx)tst-dlopen-nodelete-reloc-mod15.so +LDFLAGS-tst-dlopen-nodelete-reloc-mod16.so = -Wl,--no-as-needed +$(objpfx)tst-dlopen-nodelete-reloc-mod17.so: \ + $(objpfx)tst-dlopen-nodelete-reloc-mod15.so \ + $(objpfx)tst-dlopen-nodelete-reloc-mod16.so +LDFLAGS-tst-dlopen-nodelete-reloc-mod17.so = -Wl,--no-as-needed diff --git a/elf/dl-lookup.c b/elf/dl-lookup.c index a2e85a5568..99846918c3 100644 --- a/elf/dl-lookup.c +++ b/elf/dl-lookup.c @@ -311,12 +311,12 @@ do_lookup_unique (const char *undef_name, uint_fast32_t new_hash, enter_unique_sym (entries, size, new_hash, strtab + sym->st_name, sym, map); - if (map->l_type == lt_loaded) + if (map->l_type == lt_loaded + && map->l_nodelete == link_map_nodelete_inactive) { /* Make sure we don't unload this object by setting the appropriate flag. */ - if (__glibc_unlikely (GLRO (dl_debug_mask) & DL_DEBUG_BINDINGS) - && map->l_nodelete == link_map_nodelete_inactive) + if (__glibc_unlikely (GLRO (dl_debug_mask) & DL_DEBUG_BINDINGS)) _dl_debug_printf ("\ marking %s [%lu] as NODELETE due to unique symbol\n", map->l_name, map->l_ns); diff --git a/elf/dl-open.c b/elf/dl-open.c index df9f29a5e5..56f213323c 100644 --- a/elf/dl-open.c +++ b/elf/dl-open.c @@ -433,34 +433,21 @@ TLS generation counter wrapped! Please report this.")); after dlopen failure is not possible, so that _dl_close can clean up objects if necessary. */ static void -activate_nodelete (struct link_map *new, int mode) +activate_nodelete (struct link_map *new) { - if (mode & RTLD_NODELETE || new->l_nodelete == link_map_nodelete_pending) - { - if (__glibc_unlikely (GLRO (dl_debug_mask) & DL_DEBUG_FILES)) - _dl_debug_printf ("activating NODELETE for %s [%lu]\n", - new->l_name, new->l_ns); - new->l_nodelete = link_map_nodelete_active; - } - - for (unsigned int i = 0; i < new->l_searchlist.r_nlist; ++i) - { - struct link_map *imap = new->l_searchlist.r_list[i]; - if (imap->l_nodelete == link_map_nodelete_pending) - { - if (__glibc_unlikely (GLRO (dl_debug_mask) & DL_DEBUG_FILES)) - _dl_debug_printf ("activating NODELETE for %s [%lu]\n", - imap->l_name, imap->l_ns); - - /* Only new objects should have set - link_map_nodelete_pending. Existing objects should not - have gained any new dependencies and therefore cannot - reach NODELETE status. */ - assert (!imap->l_init_called || imap->l_type != lt_loaded); + /* It is necessary to traverse the entire namespace. References to + objects in the global scope and unique symbol bindings can force + NODELETE status for objects outside the local scope. */ + for (struct link_map *l = GL (dl_ns)[new->l_ns]._ns_loaded; l != NULL; + l = l->l_next) + if (l->l_nodelete == link_map_nodelete_pending) + { + if (__glibc_unlikely (GLRO (dl_debug_mask) & DL_DEBUG_FILES)) + _dl_debug_printf ("activating NODELETE for %s [%lu]\n", + l->l_name, l->l_ns); - imap->l_nodelete = link_map_nodelete_active; - } - } + l->l_nodelete = link_map_nodelete_active; + } } /* struct dl_init_args and call_dl_init are used to call _dl_init with @@ -721,7 +708,7 @@ dl_open_worker (void *a) All memory allocations for new objects must have happened before. */ - activate_nodelete (new, mode); + activate_nodelete (new); /* Second stage after resize_scopes: Actually perform the scope update. After this, dlsym and lazy binding can bind to new diff --git a/elf/tst-dlopen-nodelete-reloc-mod1.c b/elf/tst-dlopen-nodelete-reloc-mod1.c new file mode 100644 index 0000000000..397d60a2d5 --- /dev/null +++ b/elf/tst-dlopen-nodelete-reloc-mod1.c @@ -0,0 +1,39 @@ +/* Test propagation of NODELETE to an already-loaded object via relocation. + Non-NODELETE helper module. + Copyright (C) 2019 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 + . */ + +#include +#include +#include + +/* Globally exported. Set by the main program to true before + termination, and used by tst-dlopen-nodelete-reloc-mod2.so to + trigger marking this module as NODELETE (and also for its destructor + check). */ +bool may_finalize_mod1 = false; + +static void __attribute__ ((destructor)) +fini (void) +{ + if (!may_finalize_mod1) + { + puts ("error: tst-dlopen-nodelete-reloc-mod1.so destructor" + " called too early"); + _exit (1); + } +} diff --git a/elf/tst-dlopen-nodelete-reloc-mod10.c b/elf/tst-dlopen-nodelete-reloc-mod10.c new file mode 100644 index 0000000000..30748b73ec --- /dev/null +++ b/elf/tst-dlopen-nodelete-reloc-mod10.c @@ -0,0 +1,41 @@ +/* Helper module to load tst-dlopen-nodelete-reloc-mod11.so. + Copyright (C) 2019 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 + . */ + +#include +#include +#include +#include + +static void *handle; + +static void __attribute__ ((constructor)) +init (void) +{ + handle = dlopen ("tst-dlopen-nodelete-reloc-mod11.so", RTLD_NOW); + if (handle == NULL) + { + printf ("error: dlopen in module 10: %s\n", dlerror ()); + _exit (1); + } +} + +static void __attribute__ ((destructor)) +fini (void) +{ + dlclose (handle); +} diff --git a/elf/tst-dlopen-nodelete-reloc-mod11.cc b/elf/tst-dlopen-nodelete-reloc-mod11.cc new file mode 100644 index 0000000000..48c910403e --- /dev/null +++ b/elf/tst-dlopen-nodelete-reloc-mod11.cc @@ -0,0 +1,49 @@ +/* Second module defining a unique symbol (loaded indirectly). + Copyright (C) 2019 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 + . */ + +#include "tst-dlopen-nodelete-reloc.h" + +#include +#include +#include + +/* Just a flag here, not used for NODELETE processing. */ +bool may_finalize_mod11 = false; + +/* Trigger the creation of a unique symbol reference. This should + cause tst-dlopen-nodelete-reloc-mod9.so to be marked as + NODELETE. */ + +extern template struct unique_symbol<9>; + +int +global_function_mod11 (void) +{ + return unique_symbol<9>::value; +} + +static void __attribute__ ((destructor)) +fini (void) +{ + if (!may_finalize_mod11) + { + puts ("error: tst-dlopen-nodelete-reloc-mod11.so destructor" + " called too early"); + _exit (1); + } +} diff --git a/elf/tst-dlopen-nodelete-reloc-mod12.cc b/elf/tst-dlopen-nodelete-reloc-mod12.cc new file mode 100644 index 0000000000..5c093fd02d --- /dev/null +++ b/elf/tst-dlopen-nodelete-reloc-mod12.cc @@ -0,0 +1,42 @@ +/* First module for NODELETE test defining a unique symbol (with DT_NEEDED). + Copyright (C) 2019 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 + . */ + +#include "tst-dlopen-nodelete-reloc.h" + +#include +#include +#include + +/* Just a flag here, not used for NODELETE processing. */ +bool may_finalize_mod12 = false; + +/* Explicit instantiation. This produces a unique symbol definition + which is not referenced by the library itself, so the library is + not marked NODELETE. */ +template struct unique_symbol<12>; + +static void __attribute__ ((destructor)) +fini (void) +{ + if (!may_finalize_mod12) + { + puts ("error: tst-dlopen-nodelete-reloc-mod12.so destructor" + " called too early"); + _exit (1); + } +} diff --git a/elf/tst-dlopen-nodelete-reloc-mod13.cc b/elf/tst-dlopen-nodelete-reloc-mod13.cc new file mode 100644 index 0000000000..caf4fd1cc9 --- /dev/null +++ b/elf/tst-dlopen-nodelete-reloc-mod13.cc @@ -0,0 +1,48 @@ +/* Second module for NODELETE test defining a unique symbol (with DT_NEEDED). + Copyright (C) 2019 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 + . */ + +#include "tst-dlopen-nodelete-reloc.h" + +#include +#include +#include + +/* Just a flag here, not used for NODELETE processing. */ +bool may_finalize_mod13 = false; + +extern template struct unique_symbol<12>; + +/* Trigger the creation of a unique symbol reference. This should + cause tst-dlopen-nodelete-reloc-mod12.so to be marked as + NODELETE. */ +int +global_function_mod13 (void) +{ + return unique_symbol<12>::value; +} + +static void __attribute__ ((destructor)) +fini (void) +{ + if (!may_finalize_mod13) + { + puts ("error: tst-dlopen-nodelete-reloc-mod13.so destructor" + " called too early"); + _exit (1); + } +} diff --git a/elf/tst-dlopen-nodelete-reloc-mod13.h b/elf/tst-dlopen-nodelete-reloc-mod13.h new file mode 100644 index 0000000000..5d338481a3 --- /dev/null +++ b/elf/tst-dlopen-nodelete-reloc-mod13.h @@ -0,0 +1,24 @@ +/* Inline function which produces a unique symbol. + Copyright (C) 2019 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 + . */ + +inline char * +third_function_with_local_static (void) +{ + static char local; + return &local; +} diff --git a/elf/tst-dlopen-nodelete-reloc-mod14.cc b/elf/tst-dlopen-nodelete-reloc-mod14.cc new file mode 100644 index 0000000000..e67621a2a2 --- /dev/null +++ b/elf/tst-dlopen-nodelete-reloc-mod14.cc @@ -0,0 +1,42 @@ +/* This object must retain NODELETE status after a dlopen failure. + Copyright (C) 2019 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 + . */ + +#include "tst-dlopen-nodelete-reloc.h" + +#include +#include +#include + +/* Just a flag here, not used for NODELETE processing. */ +bool may_finalize_mod14 = false; + +/* Explicit instantiation. This produces a unique symbol definition + which is not referenced by the library itself, so the library is + not marked NODELETE. */ +template struct unique_symbol<14>; + +static void __attribute__ ((destructor)) +fini (void) +{ + if (!may_finalize_mod14) + { + puts ("error: tst-dlopen-nodelete-reloc-mod14.so destructor" + " called too early"); + _exit (1); + } +} diff --git a/elf/tst-dlopen-nodelete-reloc-mod15.cc b/elf/tst-dlopen-nodelete-reloc-mod15.cc new file mode 100644 index 0000000000..ead362bfdb --- /dev/null +++ b/elf/tst-dlopen-nodelete-reloc-mod15.cc @@ -0,0 +1,42 @@ +/* Helper object to mark tst-dlopen-nodelete-reloc-mod14.so as NODELETE. + Copyright (C) 2019 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 + . */ + +#include "tst-dlopen-nodelete-reloc.h" + +#include +#include +#include + +extern template struct unique_symbol<14>; + +/* Trigger the creation of a unique symbol reference. This should + cause tst-dlopen-nodelete-reloc-mod14.so to be marked as + NODELETE. */ +int +global_function_mod15 (void) +{ + return unique_symbol<14>::value; +} + +static void __attribute__ ((destructor)) +fini (void) +{ + /* This object is never loaded completely. */ + puts ("error: tst-dlopen-nodelete-reloc-mod15.so destructor invoked"); + _exit (1); +} diff --git a/elf/tst-dlopen-nodelete-reloc-mod16.c b/elf/tst-dlopen-nodelete-reloc-mod16.c new file mode 100644 index 0000000000..fa2ed1461b --- /dev/null +++ b/elf/tst-dlopen-nodelete-reloc-mod16.c @@ -0,0 +1,27 @@ +/* Object with an undefined symbol to trigger a relocation failure. + Copyright (C) 2019 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 + . */ + +/* The reference to undefined_mod16 triggers a relocation failure. */ + +extern int undefined_mod16; + +int +global_function_mod16 (void) +{ + return undefined_mod16; +} diff --git a/elf/tst-dlopen-nodelete-reloc-mod17.c b/elf/tst-dlopen-nodelete-reloc-mod17.c new file mode 100644 index 0000000000..426562edd9 --- /dev/null +++ b/elf/tst-dlopen-nodelete-reloc-mod17.c @@ -0,0 +1,19 @@ +/* Top-level object with dependency on an object that fails relocation. + Copyright (C) 2019 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 + . */ + +/* The dependencies do all the work. */ diff --git a/elf/tst-dlopen-nodelete-reloc-mod2.c b/elf/tst-dlopen-nodelete-reloc-mod2.c new file mode 100644 index 0000000000..81ea8e5af2 --- /dev/null +++ b/elf/tst-dlopen-nodelete-reloc-mod2.c @@ -0,0 +1,38 @@ +/* Test propagation of NODELETE to an already-loaded object via relocation. + NODELETE helper module. + Copyright (C) 2019 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 + . */ + +#include +#include +#include + +/* Defined in tst-dlopen-nodelete-reloc-mod1.so. This dependency is + not expressed via DT_NEEDED, so this reference marks the other + object as NODELETE dynamically, during initially relocation. */ +extern bool may_finalize_mod1; + +static void __attribute__ ((destructor)) +fini (void) +{ + if (!may_finalize_mod1) + { + puts ("error: tst-dlopen-nodelete-reloc-mod2.so destructor" + " called too early"); + _exit (1); + } +} diff --git a/elf/tst-dlopen-nodelete-reloc-mod3.c b/elf/tst-dlopen-nodelete-reloc-mod3.c new file mode 100644 index 0000000000..d33f4ec763 --- /dev/null +++ b/elf/tst-dlopen-nodelete-reloc-mod3.c @@ -0,0 +1,38 @@ +/* Test propagation of NODELETE to an already-loaded object via relocation. + Non-NODELETE helper module. + Copyright (C) 2019 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 + . */ + +#include +#include +#include + +/* Globally exported. Set by the main program to true before + termination, and used by tst-dlopen-nodelete-reloc-mod4.so, + tst-dlopen-nodelete-reloc-mod5.so. */ +bool may_finalize_mod3 = false; + +static void __attribute__ ((destructor)) +fini (void) +{ + if (!may_finalize_mod3) + { + puts ("error: tst-dlopen-nodelete-reloc-mod3.so destructor" + " called too early"); + _exit (1); + } +} diff --git a/elf/tst-dlopen-nodelete-reloc-mod4.c b/elf/tst-dlopen-nodelete-reloc-mod4.c new file mode 100644 index 0000000000..7e6633aebb --- /dev/null +++ b/elf/tst-dlopen-nodelete-reloc-mod4.c @@ -0,0 +1,37 @@ +/* Test propagation of NODELETE to an already-loaded object via relocation. + Intermediate helper module. + Copyright (C) 2019 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 + . */ + +#include +#include +#include + +/* Defined in tst-dlopen-nodelete-reloc-mod3.so. The dependency is + expressed via DT_NEEDED. */ +extern bool may_finalize_mod3; + +static void __attribute__ ((destructor)) +fini (void) +{ + if (!may_finalize_mod3) + { + puts ("error: tst-dlopen-nodelete-reloc-mod4.so destructor" + " called too early"); + _exit (1); + } +} diff --git a/elf/tst-dlopen-nodelete-reloc-mod5.c b/elf/tst-dlopen-nodelete-reloc-mod5.c new file mode 100644 index 0000000000..22aa16f855 --- /dev/null +++ b/elf/tst-dlopen-nodelete-reloc-mod5.c @@ -0,0 +1,38 @@ +/* Test propagation of NODELETE to an already-loaded object via relocation. + NODELETE helper module. + Copyright (C) 2019 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 + . */ + +#include +#include +#include + +/* Defined in tst-dlopen-nodelete-reloc-mod3.so. The dependency is + expressed via DT_NEEDED on the intermediate DSO + tst-dlopen-nodelete-reloc-mod3.so. */ +extern bool may_finalize_mod3; + +static void __attribute__ ((destructor)) +fini (void) +{ + if (!may_finalize_mod3) + { + puts ("error: tst-dlopen-nodelete-reloc-mod5.so destructor" + " called too early"); + _exit (1); + } +} diff --git a/elf/tst-dlopen-nodelete-reloc-mod6.cc b/elf/tst-dlopen-nodelete-reloc-mod6.cc new file mode 100644 index 0000000000..180f5b5842 --- /dev/null +++ b/elf/tst-dlopen-nodelete-reloc-mod6.cc @@ -0,0 +1,42 @@ +/* First module for NODELETE test defining a unique symbol. + Copyright (C) 2019 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 + . */ + +#include "tst-dlopen-nodelete-reloc.h" + +#include +#include +#include + +/* Just a flag here, not used for NODELETE processing. */ +bool may_finalize_mod6 = false; + +/* Explicit instantiation. This produces a unique symbol definition + which is not referenced by the library itself, so the library is + not marked NODELETE. */ +template struct unique_symbol<6>; + +static void __attribute__ ((destructor)) +fini (void) +{ + if (!may_finalize_mod6) + { + puts ("error: tst-dlopen-nodelete-reloc-mod6.so destructor" + " called too early"); + _exit (1); + } +} diff --git a/elf/tst-dlopen-nodelete-reloc-mod7.cc b/elf/tst-dlopen-nodelete-reloc-mod7.cc new file mode 100644 index 0000000000..c85e7c991b --- /dev/null +++ b/elf/tst-dlopen-nodelete-reloc-mod7.cc @@ -0,0 +1,48 @@ +/* Second module for NODELETE test defining a unique symbol. + Copyright (C) 2019 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 + . */ + +#include "tst-dlopen-nodelete-reloc.h" + +#include +#include +#include + +/* Just a flag here, not used for NODELETE processing. */ +bool may_finalize_mod7 = false; + +extern template struct unique_symbol<6>; + +/* Trigger the creation of a unique symbol reference. This should + cause tst-dlopen-nodelete-reloc-mod6.so to be marked as + NODELETE. */ +int +global_function_mod7 (void) +{ + return unique_symbol<6>::value; +} + +static void __attribute__ ((destructor)) +fini (void) +{ + if (!may_finalize_mod7) + { + puts ("error: tst-dlopen-nodelete-reloc-mod7.so destructor" + " called too early"); + _exit (1); + } +} diff --git a/elf/tst-dlopen-nodelete-reloc-mod8.c b/elf/tst-dlopen-nodelete-reloc-mod8.c new file mode 100644 index 0000000000..ebb1c35fab --- /dev/null +++ b/elf/tst-dlopen-nodelete-reloc-mod8.c @@ -0,0 +1,41 @@ +/* Helper module to load tst-dlopen-nodelete-reloc-mod9.so. + Copyright (C) 2019 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 + . */ + +#include +#include +#include +#include + +static void *handle; + +static void __attribute__ ((constructor)) +init (void) +{ + handle = dlopen ("tst-dlopen-nodelete-reloc-mod9.so", RTLD_NOW); + if (handle == NULL) + { + printf ("error: dlopen in module 8: %s\n", dlerror ()); + _exit (1); + } +} + +static void __attribute__ ((destructor)) +fini (void) +{ + dlclose (handle); +} diff --git a/elf/tst-dlopen-nodelete-reloc-mod9.cc b/elf/tst-dlopen-nodelete-reloc-mod9.cc new file mode 100644 index 0000000000..06fb49cdf7 --- /dev/null +++ b/elf/tst-dlopen-nodelete-reloc-mod9.cc @@ -0,0 +1,42 @@ +/* First module defining a unique symbol (loaded indirectly). + Copyright (C) 2019 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 + . */ + +#include "tst-dlopen-nodelete-reloc.h" + +#include +#include +#include + +/* Just a flag here, not used for NODELETE processing. */ +bool may_finalize_mod9 = false; + +/* Explicit instantiation. This produces a unique symbol definition + which is not referenced by the library itself, so the library is + not marked NODELETE. */ +template struct unique_symbol<9>; + +static void __attribute__ ((destructor)) +fini (void) +{ + if (!may_finalize_mod9) + { + puts ("error: tst-dlopen-nodelete-reloc-mod9.so destructor" + " called too early"); + _exit (1); + } +} diff --git a/elf/tst-dlopen-nodelete-reloc.c b/elf/tst-dlopen-nodelete-reloc.c new file mode 100644 index 0000000000..291ac9eb83 --- /dev/null +++ b/elf/tst-dlopen-nodelete-reloc.c @@ -0,0 +1,179 @@ +/* Test interactions of dlopen, NODELETE, and relocations. + Copyright (C) 2019 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 + . */ + +/* This test exercises NODELETE propagation due to data relocations + and unique symbols, and the interaction with already-loaded + objects. Some test objects are written in C++, to produce unique + symbol definitions. + + First test: Global scope variant, data relocation as the NODELETE + trigger. mod1 is loaded first with a separate dlopen call. + + mod2 ---(may_finalize_mod1 relocation dependency)---> mod1 + (NODELETE) (marked as NODELETE) + + Second test: Local scope variant, data relocation. mod3 is loaded + first, then mod5. + + mod5 ---(DT_NEEDED)---> mod4 ---(DT_NEEDED)---> mod3 + (NODELETE) (not NODELETE) ^ + \ / (marked as + `--(may_finalize_mod3 relocation dependency)--/ NODELETE) + + Third test: Shared local scope with unique symbol. mod6 is loaded + first, then mod7. No explicit dependencies between the two + objects, so first object has to be opened with RTLD_GLOBAL. + + mod7 ---(unique symbol)---> mod6 + (marked as NODELETE) + + Forth test: Non-shared scopes with unique symbol. mod8 and mod10 + are loaded from the main program. mod8 loads mod9 from an ELF + constructor, mod10 loads mod11. There are no DT_NEEDED + dependencies. mod9 is promoted to the global scope form the main + program. The unique symbol dependency is: + + mod9 ---(unique symbol)---> mod11 + (marked as NODELETE) + + Fifth test: Shared local scope with unique symbol, like test 3, but + this time, there is also a DT_NEEDED dependency (so no RTLD_GLOBAL + needed): + + DT_NEEDED + mod13 ---(unique symbol)---> mod12 + (marked as NODELETE) + + Sixth test: NODELETE status is retained after relocation failure + with unique symbol dependency. The object graph ensures that the + unique symbol binding is processed before the dlopen failure. + + DT_NEEDED + mod17 --(DT_NEEDED)--> mod15 --(unique symbol)--> mod14 + \ ^ (RTLD_NODELETE) + \ (DT_NEEDED) + \ | + `---(DT_NEEDED)--> mod16 + (fails to relocate) + + mod14 is loaded first, and the loading mod17 is attempted. + mod14 must remain NODELETE after opening mod17 failed. */ + +#include +#include +#include +#include +#include + +static int +do_test (void) +{ + /* First case: global scope, regular data symbol. Open the object + which is not NODELETE initially. */ + void *mod1 = xdlopen ("tst-dlopen-nodelete-reloc-mod1.so", + RTLD_NOW | RTLD_GLOBAL); + /* This is used to indicate that the ELF destructor may be + called. */ + bool *may_finalize_mod1 = xdlsym (mod1, "may_finalize_mod1"); + /* Open the NODELETE object. */ + void *mod2 = xdlopen ("tst-dlopen-nodelete-reloc-mod2.so", RTLD_NOW); + /* This has no effect because the DSO is directly marked as + NODELETE. */ + xdlclose (mod2); + /* This has no effect because the DSO has been indirectly marked as + NODELETE due to a relocation dependency. */ + xdlclose (mod1); + + /* Second case: local scope, regular data symbol. Open the object + which is not NODELETE initially. */ + void *mod3 = xdlopen ("tst-dlopen-nodelete-reloc-mod3.so", RTLD_NOW); + bool *may_finalize_mod3 = xdlsym (mod3, "may_finalize_mod3"); + /* Open the NODELETE object. */ + void *mod5 = xdlopen ("tst-dlopen-nodelete-reloc-mod5.so", RTLD_NOW); + /* Again those have no effect because of NODELETE. */ + xdlclose (mod5); + xdlclose (mod3); + + /* Third case: Unique symbol. */ + void *mod6 = xdlopen ("tst-dlopen-nodelete-reloc-mod6.so", + RTLD_NOW | RTLD_GLOBAL); + bool *may_finalize_mod6 = xdlsym (mod6, "may_finalize_mod6"); + void *mod7 = xdlopen ("tst-dlopen-nodelete-reloc-mod7.so", RTLD_NOW); + bool *may_finalize_mod7 = xdlsym (mod7, "may_finalize_mod7"); + /* This should not have any effect because of the unique symbol and + the resulting NODELETE status. */ + xdlclose (mod6); + /* mod7 is not NODELETE and can be closed. */ + *may_finalize_mod7 = true; + xdlclose (mod7); + + /* Fourth case: Unique symbol, indirect loading. */ + void *mod8 = xdlopen ("tst-dlopen-nodelete-reloc-mod8.so", RTLD_NOW); + /* Also promote to global scope. */ + void *mod9 = xdlopen ("tst-dlopen-nodelete-reloc-mod9.so", + RTLD_NOW | RTLD_NOLOAD | RTLD_GLOBAL); + bool *may_finalize_mod9 = xdlsym (mod9, "may_finalize_mod9"); + xdlclose (mod9); /* Drop mod9 reference. */ + void *mod10 = xdlopen ("tst-dlopen-nodelete-reloc-mod10.so", RTLD_NOW); + void *mod11 = xdlopen ("tst-dlopen-nodelete-reloc-mod11.so", + RTLD_NOW | RTLD_NOLOAD); + bool *may_finalize_mod11 = xdlsym (mod11, "may_finalize_mod11"); + xdlclose (mod11); /* Drop mod11 reference. */ + /* mod11 is not NODELETE and can be closed. */ + *may_finalize_mod11 = true; + /* Trigger closing of mod11, too. */ + xdlclose (mod10); + /* Does not trigger closing of mod9. */ + xdlclose (mod8); + + /* Fifth case: Unique symbol, with DT_NEEDED dependency. */ + void *mod12 = xdlopen ("tst-dlopen-nodelete-reloc-mod12.so", RTLD_NOW); + bool *may_finalize_mod12 = xdlsym (mod12, "may_finalize_mod12"); + void *mod13 = xdlopen ("tst-dlopen-nodelete-reloc-mod13.so", RTLD_NOW); + bool *may_finalize_mod13 = xdlsym (mod13, "may_finalize_mod13"); + /* This should not have any effect because of the unique symbol. */ + xdlclose (mod12); + /* mod13 is not NODELETE and can be closed. */ + *may_finalize_mod13 = true; + xdlclose (mod13); + + /* Sixth case: Unique symbol binding must not cause loss of NODELETE + status. */ + void *mod14 = xdlopen ("tst-dlopen-nodelete-reloc-mod14.so", + RTLD_NOW | RTLD_NODELETE); + bool *may_finalize_mod14 = xdlsym (mod14, "may_finalize_mod14"); + TEST_VERIFY (dlopen ("tst-dlopen-nodelete-reloc-mod17.so", RTLD_NOW) + == NULL); + const char *message = dlerror (); + printf ("info: test 6 message: %s\n", message); + /* This must not close the object, it must still be NODELETE. */ + xdlclose (mod14); + xdlopen ("tst-dlopen-nodelete-reloc-mod14.so", RTLD_NOW | RTLD_NOLOAD); + + /* Prepare for process exit. Destructors for NODELETE objects will + be invoked. */ + *may_finalize_mod1 = true; + *may_finalize_mod3 = true; + *may_finalize_mod6 = true; + *may_finalize_mod9 = true; + *may_finalize_mod12 = true; + *may_finalize_mod14 = true; + return 0; +} + +#include diff --git a/elf/tst-dlopen-nodelete-reloc.h b/elf/tst-dlopen-nodelete-reloc.h new file mode 100644 index 0000000000..8844de6226 --- /dev/null +++ b/elf/tst-dlopen-nodelete-reloc.h @@ -0,0 +1,35 @@ +/* Template to produce unique symbols. + Copyright (C) 2019 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 + . */ + +/* This template produces a unique symbol definition for an explicit + template instantiation (without also incorporating a reference), + and an extern template declaration can be used to reference that + symbol from another object. The modid parameter is just a + placeholder to create different symbols (because it affects the + name mangling of the static value member). By convention, it + should match the number of the module that contains the + definition. */ + +template +struct unique_symbol +{ + static int value; +}; + +template +int unique_symbol::value; -- cgit 1.4.1