diff options
Diffstat (limited to 'elf/rtld.c')
| -rw-r--r-- | elf/rtld.c | 2652 |
1 files changed, 0 insertions, 2652 deletions
diff --git a/elf/rtld.c b/elf/rtld.c deleted file mode 100644 index 3746653afb..0000000000 --- a/elf/rtld.c +++ /dev/null @@ -1,2652 +0,0 @@ -/* Run time dynamic linker. - Copyright (C) 1995-2017 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 - <http://www.gnu.org/licenses/>. */ - -#include <errno.h> -#include <dlfcn.h> -#include <fcntl.h> -#include <stdbool.h> -#include <stdlib.h> -#include <string.h> -#include <unistd.h> -#include <sys/mman.h> -#include <sys/param.h> -#include <sys/stat.h> -#include <ldsodefs.h> -#include <_itoa.h> -#include <entry.h> -#include <fpu_control.h> -#include <hp-timing.h> -#include <libc-lock.h> -#include "dynamic-link.h" -#include <dl-librecon.h> -#include <unsecvars.h> -#include <dl-cache.h> -#include <dl-osinfo.h> -#include <dl-procinfo.h> -#include <tls.h> -#include <stap-probe.h> -#include <stackinfo.h> - -#include <assert.h> - -/* Avoid PLT use for our local calls at startup. */ -extern __typeof (__mempcpy) __mempcpy attribute_hidden; - -/* GCC has mental blocks about _exit. */ -extern __typeof (_exit) exit_internal asm ("_exit") attribute_hidden; -#define _exit exit_internal - -/* Helper function to handle errors while resolving symbols. */ -static void print_unresolved (int errcode, const char *objname, - const char *errsting); - -/* Helper function to handle errors when a version is missing. */ -static void print_missing_version (int errcode, const char *objname, - const char *errsting); - -/* Print the various times we collected. */ -static void print_statistics (hp_timing_t *total_timep); - -/* Add audit objects. */ -static void process_dl_audit (char *str); - -/* This is a list of all the modes the dynamic loader can be in. */ -enum mode { normal, list, verify, trace }; - -/* Process all environments variables the dynamic linker must recognize. - Since all of them start with `LD_' we are a bit smarter while finding - all the entries. */ -static void process_envvars (enum mode *modep); - -#ifdef DL_ARGV_NOT_RELRO -int _dl_argc attribute_hidden; -char **_dl_argv = NULL; -/* Nonzero if we were run directly. */ -unsigned int _dl_skip_args attribute_hidden; -#else -int _dl_argc attribute_relro attribute_hidden; -char **_dl_argv attribute_relro = NULL; -unsigned int _dl_skip_args attribute_relro attribute_hidden; -#endif -rtld_hidden_data_def (_dl_argv) - -#ifndef THREAD_SET_STACK_GUARD -/* Only exported for architectures that don't store the stack guard canary - in thread local area. */ -uintptr_t __stack_chk_guard attribute_relro; -#endif - -/* Only exported for architectures that don't store the pointer guard - value in thread local area. */ -uintptr_t __pointer_chk_guard_local - attribute_relro attribute_hidden __attribute__ ((nocommon)); -#ifndef THREAD_SET_POINTER_GUARD -strong_alias (__pointer_chk_guard_local, __pointer_chk_guard) -#endif - - -/* List of auditing DSOs. */ -static struct audit_list -{ - const char *name; - struct audit_list *next; -} *audit_list; - -#ifndef HAVE_INLINED_SYSCALLS -/* Set nonzero during loading and initialization of executable and - libraries, cleared before the executable's entry point runs. This - must not be initialized to nonzero, because the unused dynamic - linker loaded in for libc.so's "ld.so.1" dep will provide the - definition seen by libc.so's initializer; that value must be zero, - and will be since that dynamic linker's _dl_start and dl_main will - never be called. */ -int _dl_starting_up = 0; -rtld_hidden_def (_dl_starting_up) -#endif - -/* This is the structure which defines all variables global to ld.so - (except those which cannot be added for some reason). */ -struct rtld_global _rtld_global = - { - /* Generally the default presumption without further information is an - * executable stack but this is not true for all platforms. */ - ._dl_stack_flags = DEFAULT_STACK_PERMS, -#ifdef _LIBC_REENTRANT - ._dl_load_lock = _RTLD_LOCK_RECURSIVE_INITIALIZER, - ._dl_load_write_lock = _RTLD_LOCK_RECURSIVE_INITIALIZER, -#endif - ._dl_nns = 1, - ._dl_ns = - { -#ifdef _LIBC_REENTRANT - [LM_ID_BASE] = { ._ns_unique_sym_table - = { .lock = _RTLD_LOCK_RECURSIVE_INITIALIZER } } -#endif - } - }; -/* If we would use strong_alias here the compiler would see a - non-hidden definition. This would undo the effect of the previous - declaration. So spell out was strong_alias does plus add the - visibility attribute. */ -extern struct rtld_global _rtld_local - __attribute__ ((alias ("_rtld_global"), visibility ("hidden"))); - - -/* This variable is similar to _rtld_local, but all values are - read-only after relocation. */ -struct rtld_global_ro _rtld_global_ro attribute_relro = - { - /* Get architecture specific initializer. */ -#include <dl-procinfo.c> -#ifdef NEED_DL_SYSINFO - ._dl_sysinfo = DL_SYSINFO_DEFAULT, -#endif - ._dl_debug_fd = STDERR_FILENO, - ._dl_use_load_bias = -2, - ._dl_correct_cache_id = _DL_CACHE_DEFAULT_ID, -#if !HAVE_TUNABLES - ._dl_hwcap_mask = HWCAP_IMPORTANT, -#endif - ._dl_lazy = 1, - ._dl_fpu_control = _FPU_DEFAULT, - ._dl_pagesize = EXEC_PAGESIZE, - ._dl_inhibit_cache = 0, - - /* Function pointers. */ - ._dl_debug_printf = _dl_debug_printf, - ._dl_mcount = _dl_mcount, - ._dl_lookup_symbol_x = _dl_lookup_symbol_x, - ._dl_check_caller = _dl_check_caller, - ._dl_open = _dl_open, - ._dl_close = _dl_close, - ._dl_tls_get_addr_soft = _dl_tls_get_addr_soft, -#ifdef HAVE_DL_DISCOVER_OSVERSION - ._dl_discover_osversion = _dl_discover_osversion -#endif - }; -/* If we would use strong_alias here the compiler would see a - non-hidden definition. This would undo the effect of the previous - declaration. So spell out was strong_alias does plus add the - visibility attribute. */ -extern struct rtld_global_ro _rtld_local_ro - __attribute__ ((alias ("_rtld_global_ro"), visibility ("hidden"))); - - -static void dl_main (const ElfW(Phdr) *phdr, ElfW(Word) phnum, - ElfW(Addr) *user_entry, ElfW(auxv_t) *auxv); - -/* These two variables cannot be moved into .data.rel.ro. */ -static struct libname_list _dl_rtld_libname; -static struct libname_list _dl_rtld_libname2; - -/* Variable for statistics. */ -#ifndef HP_TIMING_NONAVAIL -static hp_timing_t relocate_time; -static hp_timing_t load_time attribute_relro; -static hp_timing_t start_time attribute_relro; -#endif - -/* Additional definitions needed by TLS initialization. */ -#ifdef TLS_INIT_HELPER -TLS_INIT_HELPER -#endif - -/* Helper function for syscall implementation. */ -#ifdef DL_SYSINFO_IMPLEMENTATION -DL_SYSINFO_IMPLEMENTATION -#endif - -/* Before ld.so is relocated we must not access variables which need - relocations. This means variables which are exported. Variables - declared as static are fine. If we can mark a variable hidden this - is fine, too. The latter is important here. We can avoid setting - up a temporary link map for ld.so if we can mark _rtld_global as - hidden. */ -#ifdef PI_STATIC_AND_HIDDEN -# define DONT_USE_BOOTSTRAP_MAP 1 -#endif - -#ifdef DONT_USE_BOOTSTRAP_MAP -static ElfW(Addr) _dl_start_final (void *arg); -#else -struct dl_start_final_info -{ - struct link_map l; -#if !defined HP_TIMING_NONAVAIL && HP_TIMING_INLINE - hp_timing_t start_time; -#endif -}; -static ElfW(Addr) _dl_start_final (void *arg, - struct dl_start_final_info *info); -#endif - -/* These defined magically in the linker script. */ -extern char _begin[] attribute_hidden; -extern char _etext[] attribute_hidden; -extern char _end[] attribute_hidden; - - -#ifdef RTLD_START -RTLD_START -#else -# error "sysdeps/MACHINE/dl-machine.h fails to define RTLD_START" -#endif - -/* This is the second half of _dl_start (below). It can be inlined safely - under DONT_USE_BOOTSTRAP_MAP, where it is careful not to make any GOT - references. When the tools don't permit us to avoid using a GOT entry - for _dl_rtld_global (no attribute_hidden support), we must make sure - this function is not inlined (see below). */ - -#ifdef DONT_USE_BOOTSTRAP_MAP -static inline ElfW(Addr) __attribute__ ((always_inline)) -_dl_start_final (void *arg) -#else -static ElfW(Addr) __attribute__ ((noinline)) -_dl_start_final (void *arg, struct dl_start_final_info *info) -#endif -{ - ElfW(Addr) start_addr; - - if (HP_SMALL_TIMING_AVAIL) - { - /* If it hasn't happen yet record the startup time. */ - if (! HP_TIMING_INLINE) - HP_TIMING_NOW (start_time); -#if !defined DONT_USE_BOOTSTRAP_MAP && !defined HP_TIMING_NONAVAIL - else - start_time = info->start_time; -#endif - } - - /* Transfer data about ourselves to the permanent link_map structure. */ -#ifndef DONT_USE_BOOTSTRAP_MAP - GL(dl_rtld_map).l_addr = info->l.l_addr; - GL(dl_rtld_map).l_ld = info->l.l_ld; - memcpy (GL(dl_rtld_map).l_info, info->l.l_info, - sizeof GL(dl_rtld_map).l_info); - GL(dl_rtld_map).l_mach = info->l.l_mach; - GL(dl_rtld_map).l_relocated = 1; -#endif - _dl_setup_hash (&GL(dl_rtld_map)); - GL(dl_rtld_map).l_real = &GL(dl_rtld_map); - GL(dl_rtld_map).l_map_start = (ElfW(Addr)) _begin; - GL(dl_rtld_map).l_map_end = (ElfW(Addr)) _end; - GL(dl_rtld_map).l_text_end = (ElfW(Addr)) _etext; - /* Copy the TLS related data if necessary. */ -#ifndef DONT_USE_BOOTSTRAP_MAP -# if NO_TLS_OFFSET != 0 - GL(dl_rtld_map).l_tls_offset = NO_TLS_OFFSET; -# endif -#endif - - HP_TIMING_NOW (GL(dl_cpuclock_offset)); - - /* Initialize the stack end variable. */ - __libc_stack_end = __builtin_frame_address (0); - - /* Call the OS-dependent function to set up life so we can do things like - file access. It will call `dl_main' (below) to do all the real work - of the dynamic linker, and then unwind our frame and run the user - entry point on the same stack we entered on. */ - start_addr = _dl_sysdep_start (arg, &dl_main); - -#ifndef HP_TIMING_NONAVAIL - hp_timing_t rtld_total_time; - if (HP_SMALL_TIMING_AVAIL) - { - hp_timing_t end_time; - - /* Get the current time. */ - HP_TIMING_NOW (end_time); - - /* Compute the difference. */ - HP_TIMING_DIFF (rtld_total_time, start_time, end_time); - } -#endif - - if (__glibc_unlikely (GLRO(dl_debug_mask) & DL_DEBUG_STATISTICS)) - { -#ifndef HP_TIMING_NONAVAIL - print_statistics (&rtld_total_time); -#else - print_statistics (NULL); -#endif - } - - return start_addr; -} - -static ElfW(Addr) __attribute_used__ internal_function -_dl_start (void *arg) -{ -#ifdef DONT_USE_BOOTSTRAP_MAP -# define bootstrap_map GL(dl_rtld_map) -#else - struct dl_start_final_info info; -# define bootstrap_map info.l -#endif - - /* This #define produces dynamic linking inline functions for - bootstrap relocation instead of general-purpose relocation. - Since ld.so must not have any undefined symbols the result - is trivial: always the map of ld.so itself. */ -#define RTLD_BOOTSTRAP -#define RESOLVE_MAP(sym, version, flags) (&bootstrap_map) -#include "dynamic-link.h" - - if (HP_TIMING_INLINE && HP_SMALL_TIMING_AVAIL) -#ifdef DONT_USE_BOOTSTRAP_MAP - HP_TIMING_NOW (start_time); -#else - HP_TIMING_NOW (info.start_time); -#endif - - /* Partly clean the `bootstrap_map' structure up. Don't use - `memset' since it might not be built in or inlined and we cannot - make function calls at this point. Use '__builtin_memset' if we - know it is available. We do not have to clear the memory if we - do not have to use the temporary bootstrap_map. Global variables - are initialized to zero by default. */ -#ifndef DONT_USE_BOOTSTRAP_MAP -# ifdef HAVE_BUILTIN_MEMSET - __builtin_memset (bootstrap_map.l_info, '\0', sizeof (bootstrap_map.l_info)); -# else - for (size_t cnt = 0; - cnt < sizeof (bootstrap_map.l_info) / sizeof (bootstrap_map.l_info[0]); - ++cnt) - bootstrap_map.l_info[cnt] = 0; -# endif -#endif - - /* Figure out the run-time load address of the dynamic linker itself. */ - bootstrap_map.l_addr = elf_machine_load_address (); - - /* Read our own dynamic section and fill in the info array. */ - bootstrap_map.l_ld = (void *) bootstrap_map.l_addr + elf_machine_dynamic (); - elf_get_dynamic_info (&bootstrap_map, NULL); - -#if NO_TLS_OFFSET != 0 - bootstrap_map.l_tls_offset = NO_TLS_OFFSET; -#endif - -#ifdef ELF_MACHINE_BEFORE_RTLD_RELOC - ELF_MACHINE_BEFORE_RTLD_RELOC (bootstrap_map.l_info); -#endif - - if (bootstrap_map.l_addr || ! bootstrap_map.l_info[VALIDX(DT_GNU_PRELINKED)]) - { - /* Relocate ourselves so we can do normal function calls and - data access using the global offset table. */ - - ELF_DYNAMIC_RELOCATE (&bootstrap_map, 0, 0, 0); - } - bootstrap_map.l_relocated = 1; - - /* Please note that we don't allow profiling of this object and - therefore need not test whether we have to allocate the array - for the relocation results (as done in dl-reloc.c). */ - - /* Now life is sane; we can call functions and access global data. - Set up to use the operating system facilities, and find out from - the operating system's program loader where to find the program - header table in core. Put the rest of _dl_start into a separate - function, that way the compiler cannot put accesses to the GOT - before ELF_DYNAMIC_RELOCATE. */ - { -#ifdef DONT_USE_BOOTSTRAP_MAP - ElfW(Addr) entry = _dl_start_final (arg); -#else - ElfW(Addr) entry = _dl_start_final (arg, &info); -#endif - -#ifndef ELF_MACHINE_START_ADDRESS -# define ELF_MACHINE_START_ADDRESS(map, start) (start) -#endif - - return ELF_MACHINE_START_ADDRESS (GL(dl_ns)[LM_ID_BASE]._ns_loaded, entry); - } -} - - - -/* Now life is peachy; we can do all normal operations. - On to the real work. */ - -/* Some helper functions. */ - -/* Arguments to relocate_doit. */ -struct relocate_args -{ - struct link_map *l; - int reloc_mode; -}; - -struct map_args -{ - /* Argument to map_doit. */ - const char *str; - struct link_map *loader; - int mode; - /* Return value of map_doit. */ - struct link_map *map; -}; - -struct dlmopen_args -{ - const char *fname; - struct link_map *map; -}; - -struct lookup_args -{ - const char *name; - struct link_map *map; - void *result; -}; - -/* Arguments to version_check_doit. */ -struct version_check_args -{ - int doexit; - int dotrace; -}; - -static void -relocate_doit (void *a) -{ - struct relocate_args *args = (struct relocate_args *) a; - - _dl_relocate_object (args->l, args->l->l_scope, args->reloc_mode, 0); -} - -static void -map_doit (void *a) -{ - struct map_args *args = (struct map_args *) a; - int type = (args->mode == __RTLD_OPENEXEC) ? lt_executable : lt_library; - args->map = _dl_map_object (args->loader, args->str, type, 0, - args->mode, LM_ID_BASE); -} - -static void -dlmopen_doit (void *a) -{ - struct dlmopen_args *args = (struct dlmopen_args *) a; - args->map = _dl_open (args->fname, - (RTLD_LAZY | __RTLD_DLOPEN | __RTLD_AUDIT - | __RTLD_SECURE), - dl_main, LM_ID_NEWLM, _dl_argc, _dl_argv, - __environ); -} - -static void -lookup_doit (void *a) -{ - struct lookup_args *args = (struct lookup_args *) a; - const ElfW(Sym) *ref = NULL; - args->result = NULL; - lookup_t l = _dl_lookup_symbol_x (args->name, args->map, &ref, - args->map->l_local_scope, NULL, 0, - DL_LOOKUP_RETURN_NEWEST, NULL); - if (ref != NULL) - args->result = DL_SYMBOL_ADDRESS (l, ref); -} - -static void -version_check_doit (void *a) -{ - struct version_check_args *args = (struct version_check_args *) a; - if (_dl_check_all_versions (GL(dl_ns)[LM_ID_BASE]._ns_loaded, 1, - args->dotrace) && args->doexit) - /* We cannot start the application. Abort now. */ - _exit (1); -} - - -static inline struct link_map * -find_needed (const char *name) -{ - struct r_scope_elem *scope = &GL(dl_ns)[LM_ID_BASE]._ns_loaded->l_searchlist; - unsigned int n = scope->r_nlist; - - while (n-- > 0) - if (_dl_name_match_p (name, scope->r_list[n])) - return scope->r_list[n]; - - /* Should never happen. */ - return NULL; -} - -static int -match_version (const char *string, struct link_map *map) -{ - const char *strtab = (const void *) D_PTR (map, l_info[DT_STRTAB]); - ElfW(Verdef) *def; - -#define VERDEFTAG (DT_NUM + DT_THISPROCNUM + DT_VERSIONTAGIDX (DT_VERDEF)) - if (map->l_info[VERDEFTAG] == NULL) - /* The file has no symbol versioning. */ - return 0; - - def = (ElfW(Verdef) *) ((char *) map->l_addr - + map->l_info[VERDEFTAG]->d_un.d_ptr); - while (1) - { - ElfW(Verdaux) *aux = (ElfW(Verdaux) *) ((char *) def + def->vd_aux); - - /* Compare the version strings. */ - if (strcmp (string, strtab + aux->vda_name) == 0) - /* Bingo! */ - return 1; - - /* If no more definitions we failed to find what we want. */ - if (def->vd_next == 0) - break; - - /* Next definition. */ - def = (ElfW(Verdef) *) ((char *) def + def->vd_next); - } - - return 0; -} - -static bool tls_init_tp_called; - -static void * -init_tls (void) -{ - /* Number of elements in the static TLS block. */ - GL(dl_tls_static_nelem) = GL(dl_tls_max_dtv_idx); - - /* Do not do this twice. The audit interface might have required - the DTV interfaces to be set up early. */ - if (GL(dl_initial_dtv) != NULL) - return NULL; - - /* Allocate the array which contains the information about the - dtv slots. We allocate a few entries more than needed to - avoid the need for reallocation. */ - size_t nelem = GL(dl_tls_max_dtv_idx) + 1 + TLS_SLOTINFO_SURPLUS; - - /* Allocate. */ - GL(dl_tls_dtv_slotinfo_list) = (struct dtv_slotinfo_list *) - calloc (sizeof (struct dtv_slotinfo_list) - + nelem * sizeof (struct dtv_slotinfo), 1); - /* No need to check the return value. If memory allocation failed - the program would have been terminated. */ - - struct dtv_slotinfo *slotinfo = GL(dl_tls_dtv_slotinfo_list)->slotinfo; - GL(dl_tls_dtv_slotinfo_list)->len = nelem; - GL(dl_tls_dtv_slotinfo_list)->next = NULL; - - /* Fill in the information from the loaded modules. No namespace - but the base one can be filled at this time. */ - assert (GL(dl_ns)[LM_ID_BASE + 1]._ns_loaded == NULL); - int i = 0; - for (struct link_map *l = GL(dl_ns)[LM_ID_BASE]._ns_loaded; l != NULL; - l = l->l_next) - if (l->l_tls_blocksize != 0) - { - /* This is a module with TLS data. Store the map reference. - The generation counter is zero. */ - slotinfo[i].map = l; - /* slotinfo[i].gen = 0; */ - ++i; - } - assert (i == GL(dl_tls_max_dtv_idx)); - - /* Compute the TLS offsets for the various blocks. */ - _dl_determine_tlsoffset (); - - /* Construct the static TLS block and the dtv for the initial - thread. For some platforms this will include allocating memory - for the thread descriptor. The memory for the TLS block will - never be freed. It should be allocated accordingly. The dtv - array can be changed if dynamic loading requires it. */ - void *tcbp = _dl_allocate_tls_storage (); - if (tcbp == NULL) - _dl_fatal_printf ("\ -cannot allocate TLS data structures for initial thread"); - - /* Store for detection of the special case by __tls_get_addr - so it knows not to pass this dtv to the normal realloc. */ - GL(dl_initial_dtv) = GET_DTV (tcbp); - - /* And finally install it for the main thread. */ - const char *lossage = TLS_INIT_TP (tcbp); - if (__glibc_unlikely (lossage != NULL)) - _dl_fatal_printf ("cannot set up thread-local storage: %s\n", lossage); - tls_init_tp_called = true; - - return tcbp; -} - -static unsigned int -do_preload (const char *fname, struct link_map *main_map, const char *where) -{ - const char *objname; - const char *err_str = NULL; - struct map_args args; - bool malloced; - - args.str = fname; - args.loader = main_map; - args.mode = __RTLD_SECURE; - - unsigned int old_nloaded = GL(dl_ns)[LM_ID_BASE]._ns_nloaded; - - (void) _dl_catch_error (&objname, &err_str, &malloced, map_doit, &args); - if (__glibc_unlikely (err_str != NULL)) - { - _dl_error_printf ("\ -ERROR: ld.so: object '%s' from %s cannot be preloaded (%s): ignored.\n", - fname, where, err_str); - /* No need to call free, this is still before - the libc's malloc is used. */ - } - else if (GL(dl_ns)[LM_ID_BASE]._ns_nloaded != old_nloaded) - /* It is no duplicate. */ - return 1; - - /* Nothing loaded. */ - return 0; -} - -#if defined SHARED && defined _LIBC_REENTRANT \ - && defined __rtld_lock_default_lock_recursive -static void -rtld_lock_default_lock_recursive (void *lock) -{ - __rtld_lock_default_lock_recursive (lock); -} - -static void -rtld_lock_default_unlock_recursive (void *lock) -{ - __rtld_lock_default_unlock_recursive (lock); -} -#endif - - -static void -security_init (void) -{ - /* Set up the stack checker's canary. */ - uintptr_t stack_chk_guard = _dl_setup_stack_chk_guard (_dl_random); -#ifdef THREAD_SET_STACK_GUARD - THREAD_SET_STACK_GUARD (stack_chk_guard); -#else - __stack_chk_guard = stack_chk_guard; -#endif - - /* Set up the pointer guard as well, if necessary. */ - uintptr_t pointer_chk_guard - = _dl_setup_pointer_guard (_dl_random, stack_chk_guard); -#ifdef THREAD_SET_POINTER_GUARD - THREAD_SET_POINTER_GUARD (pointer_chk_guard); -#endif - __pointer_chk_guard_local = pointer_chk_guard; - - /* We do not need the _dl_random value anymore. The less - information we leave behind, the better, so clear the - variable. */ - _dl_random = NULL; -} - -#include "setup-vdso.h" - -/* The library search path. */ -static const char *library_path attribute_relro; -/* The list preloaded objects. */ -static const char *preloadlist attribute_relro; -/* Nonzero if information about versions has to be printed. */ -static int version_info attribute_relro; - -static void -dl_main (const ElfW(Phdr) *phdr, - ElfW(Word) phnum, - ElfW(Addr) *user_entry, - ElfW(auxv_t) *auxv) -{ - const ElfW(Phdr) *ph; - enum mode mode; - struct link_map *main_map; - size_t file_size; - char *file; - bool has_interp = false; - unsigned int i; - bool prelinked = false; - bool rtld_is_main = false; -#ifndef HP_TIMING_NONAVAIL - hp_timing_t start; - hp_timing_t stop; - hp_timing_t diff; -#endif - void *tcbp = NULL; - - GL(dl_init_static_tls) = &_dl_nothread_init_static_tls; - -#if defined SHARED && defined _LIBC_REENTRANT \ - && defined __rtld_lock_default_lock_recursive - GL(dl_rtld_lock_recursive) = rtld_lock_default_lock_recursive; - GL(dl_rtld_unlock_recursive) = rtld_lock_default_unlock_recursive; -#endif - - /* The explicit initialization here is cheaper than processing the reloc - in the _rtld_local definition's initializer. */ - GL(dl_make_stack_executable_hook) = &_dl_make_stack_executable; - - /* Process the environment variable which control the behaviour. */ - process_envvars (&mode); - -#ifndef HAVE_INLINED_SYSCALLS - /* Set up a flag which tells we are just starting. */ - _dl_starting_up = 1; -#endif - - if (*user_entry == (ElfW(Addr)) ENTRY_POINT) - { - /* Ho ho. We are not the program interpreter! We are the program - itself! This means someone ran ld.so as a command. Well, that - might be convenient to do sometimes. We support it by - interpreting the args like this: - - ld.so PROGRAM ARGS... - - The first argument is the name of a file containing an ELF - executable we will load and run with the following arguments. - To simplify life here, PROGRAM is searched for using the - normal rules for shared objects, rather than $PATH or anything - like that. We just load it and use its entry point; we don't - pay attention to its PT_INTERP command (we are the interpreter - ourselves). This is an easy way to test a new ld.so before - installing it. */ - rtld_is_main = true; - - /* Note the place where the dynamic linker actually came from. */ - GL(dl_rtld_map).l_name = rtld_progname; - - while (_dl_argc > 1) - if (! strcmp (_dl_argv[1], "--list")) - { - mode = list; - GLRO(dl_lazy) = -1; /* This means do no dependency analysis. */ - - ++_dl_skip_args; - --_dl_argc; - ++_dl_argv; - } - else if (! strcmp (_dl_argv[1], "--verify")) - { - mode = verify; - - ++_dl_skip_args; - --_dl_argc; - ++_dl_argv; - } - else if (! strcmp (_dl_argv[1], "--inhibit-cache")) - { - GLRO(dl_inhibit_cache) = 1; - ++_dl_skip_args; - --_dl_argc; - ++_dl_argv; - } - else if (! strcmp (_dl_argv[1], "--library-path") - && _dl_argc > 2) - { - library_path = _dl_argv[2]; - - _dl_skip_args += 2; - _dl_argc -= 2; - _dl_argv += 2; - } - else if (! strcmp (_dl_argv[1], "--inhibit-rpath") - && _dl_argc > 2) - { - GLRO(dl_inhibit_rpath) = _dl_argv[2]; - - _dl_skip_args += 2; - _dl_argc -= 2; - _dl_argv += 2; - } - else if (! strcmp (_dl_argv[1], "--audit") && _dl_argc > 2) - { - process_dl_audit (_dl_argv[2]); - - _dl_skip_args += 2; - _dl_argc -= 2; - _dl_argv += 2; - } - else - break; - - /* If we have no further argument the program was called incorrectly. - Grant the user some education. */ - if (_dl_argc < 2) - _dl_fatal_printf ("\ -Usage: ld.so [OPTION]... EXECUTABLE-FILE [ARGS-FOR-PROGRAM...]\n\ -You have invoked `ld.so', the helper program for shared library executables.\n\ -This program usually lives in the file `/lib/ld.so', and special directives\n\ -in executable files using ELF shared libraries tell the system's program\n\ -loader to load the helper program from this file. This helper program loads\n\ -the shared libraries needed by the program executable, prepares the program\n\ -to run, and runs it. You may invoke this helper program directly from the\n\ -command line to load and run an ELF executable file; this is like executing\n\ -that file itself, but always uses this helper program from the file you\n\ -specified, instead of the helper program file specified in the executable\n\ -file you run. This is mostly of use for maintainers to test new versions\n\ -of this helper program; chances are you did not intend to run this program.\n\ -\n\ - --list list all dependencies and how they are resolved\n\ - --verify verify that given object really is a dynamically linked\n\ - object we can handle\n\ - --inhibit-cache Do not use " LD_SO_CACHE "\n\ - --library-path PATH use given PATH instead of content of the environment\n\ - variable LD_LIBRARY_PATH\n\ - --inhibit-rpath LIST ignore RUNPATH and RPATH information in object names\n\ - in LIST\n\ - --audit LIST use objects named in LIST as auditors\n"); - - ++_dl_skip_args; - --_dl_argc; - ++_dl_argv; - - /* The initialization of _dl_stack_flags done below assumes the - executable's PT_GNU_STACK may have been honored by the kernel, and - so a PT_GNU_STACK with PF_X set means the stack started out with - execute permission. However, this is not really true if the - dynamic linker is the executable the kernel loaded. For this - case, we must reinitialize _dl_stack_flags to match the dynamic - linker itself. If the dynamic linker was built with a - PT_GNU_STACK, then the kernel may have loaded us with a - nonexecutable stack that we will have to make executable when we - load the program below unless it has a PT_GNU_STACK indicating - nonexecutable stack is ok. */ - - for (ph = phdr; ph < &phdr[phnum]; ++ph) - if (ph->p_type == PT_GNU_STACK) - { - GL(dl_stack_flags) = ph->p_flags; - break; - } - - if (__builtin_expect (mode, normal) == verify) - { - const char *objname; - const char *err_str = NULL; - struct map_args args; - bool malloced; - - args.str = rtld_progname; - args.loader = NULL; - args.mode = __RTLD_OPENEXEC; - (void) _dl_catch_error (&objname, &err_str, &malloced, map_doit, - &args); - if (__glibc_unlikely (err_str != NULL)) - /* We don't free the returned string, the programs stops - anyway. */ - _exit (EXIT_FAILURE); - } - else - { - HP_TIMING_NOW (start); - _dl_map_object (NULL, rtld_progname, lt_executable, 0, - __RTLD_OPENEXEC, LM_ID_BASE); - HP_TIMING_NOW (stop); - - HP_TIMING_DIFF (load_time, start, stop); - } - - /* Now the map for the main executable is available. */ - main_map = GL(dl_ns)[LM_ID_BASE]._ns_loaded; - - if (__builtin_expect (mode, normal) == normal - && GL(dl_rtld_map).l_info[DT_SONAME] != NULL - && main_map->l_info[DT_SONAME] != NULL - && strcmp ((const char *) D_PTR (&GL(dl_rtld_map), l_info[DT_STRTAB]) - + GL(dl_rtld_map).l_info[DT_SONAME]->d_un.d_val, - (const char *) D_PTR (main_map, l_info[DT_STRTAB]) - + main_map->l_info[DT_SONAME]->d_un.d_val) == 0) - _dl_fatal_printf ("loader cannot load itself\n"); - - phdr = main_map->l_phdr; - phnum = main_map->l_phnum; - /* We overwrite here a pointer to a malloc()ed string. But since - the malloc() implementation used at this point is the dummy - implementations which has no real free() function it does not - makes sense to free the old string first. */ - main_map->l_name = (char *) ""; - *user_entry = main_map->l_entry; - -#ifdef HAVE_AUX_VECTOR - /* Adjust the on-stack auxiliary vector so that it looks like the - binary was executed directly. */ - for (ElfW(auxv_t) *av = auxv; av->a_type != AT_NULL; av++) - switch (av->a_type) - { - case AT_PHDR: - av->a_un.a_val = (uintptr_t) phdr; - break; - case AT_PHNUM: - av->a_un.a_val = phnum; - break; - case AT_ENTRY: - av->a_un.a_val = *user_entry; - break; - case AT_EXECFN: - av->a_un.a_val = (uintptr_t) _dl_argv[0]; - break; - } -#endif - } - else - { - /* Create a link_map for the executable itself. - This will be what dlopen on "" returns. */ - main_map = _dl_new_object ((char *) "", "", lt_executable, NULL, - __RTLD_OPENEXEC, LM_ID_BASE); - assert (main_map != NULL); - main_map->l_phdr = phdr; - main_map->l_phnum = phnum; - main_map->l_entry = *user_entry; - - /* Even though the link map is not yet fully initialized we can add - it to the map list since there are no possible users running yet. */ - _dl_add_to_namespace_list (main_map, LM_ID_BASE); - assert (main_map == GL(dl_ns)[LM_ID_BASE]._ns_loaded); - - /* At this point we are in a bit of trouble. We would have to - fill in the values for l_dev and l_ino. But in general we - do not know where the file is. We also do not handle AT_EXECFD - even if it would be passed up. - - We leave the values here defined to 0. This is normally no - problem as the program code itself is normally no shared - object and therefore cannot be loaded dynamically. Nothing - prevent the use of dynamic binaries and in these situations - we might get problems. We might not be able to find out - whether the object is already loaded. But since there is no - easy way out and because the dynamic binary must also not - have an SONAME we ignore this program for now. If it becomes - a problem we can force people using SONAMEs. */ - - /* We delay initializing the path structure until we got the dynamic - information for the program. */ - } - - main_map->l_map_end = 0; - main_map->l_text_end = 0; - /* Perhaps the executable has no PT_LOAD header entries at all. */ - main_map->l_map_start = ~0; - /* And it was opened directly. */ - ++main_map->l_direct_opencount; - - /* Scan the program header table for the dynamic section. */ - for (ph = phdr; ph < &phdr[phnum]; ++ph) - switch (ph->p_type) - { - case PT_PHDR: - /* Find out the load address. */ - main_map->l_addr = (ElfW(Addr)) phdr - ph->p_vaddr; - break; - case PT_DYNAMIC: - /* This tells us where to find the dynamic section, - which tells us everything we need to do. */ - main_map->l_ld = (void *) main_map->l_addr + ph->p_vaddr; - break; - case PT_INTERP: - /* This "interpreter segment" was used by the program loader to - find the program interpreter, which is this program itself, the - dynamic linker. We note what name finds us, so that a future - dlopen call or DT_NEEDED entry, for something that wants to link - against the dynamic linker as a shared library, will know that - the shared object is already loaded. */ - _dl_rtld_libname.name = ((const char *) main_map->l_addr - + ph->p_vaddr); - /* _dl_rtld_libname.next = NULL; Already zero. */ - GL(dl_rtld_map).l_libname = &_dl_rtld_libname; - - /* Ordinarilly, we would get additional names for the loader from - our DT_SONAME. This can't happen if we were actually linked as - a static executable (detect this case when we have no DYNAMIC). - If so, assume the filename component of the interpreter path to - be our SONAME, and add it to our name list. */ - if (GL(dl_rtld_map).l_ld == NULL) - { - const char *p = NULL; - const char *cp = _dl_rtld_libname.name; - - /* Find the filename part of the path. */ - while (*cp != '\0') - if (*cp++ == '/') - p = cp; - - if (p != NULL) - { - _dl_rtld_libname2.name = p; - /* _dl_rtld_libname2.next = NULL; Already zero. */ - _dl_rtld_libname.next = &_dl_rtld_libname2; - } - } - - has_interp = true; - break; - case PT_LOAD: - { - ElfW(Addr) mapstart; - ElfW(Addr) allocend; - - /* Remember where the main program starts in memory. */ - mapstart = (main_map->l_addr - + (ph->p_vaddr & ~(GLRO(dl_pagesize) - 1))); - if (main_map->l_map_start > mapstart) - main_map->l_map_start = mapstart; - - /* Also where it ends. */ - allocend = main_map->l_addr + ph->p_vaddr + ph->p_memsz; - if (main_map->l_map_end < allocend) - main_map->l_map_end = allocend; - if ((ph->p_flags & PF_X) && allocend > main_map->l_text_end) - main_map->l_text_end = allocend; - } - break; - - case PT_TLS: - if (ph->p_memsz > 0) - { - /* Note that in the case the dynamic linker we duplicate work - here since we read the PT_TLS entry already in - _dl_start_final. But the result is repeatable so do not - check for this special but unimportant case. */ - main_map->l_tls_blocksize = ph->p_memsz; - main_map->l_tls_align = ph->p_align; - if (ph->p_align == 0) - main_map->l_tls_firstbyte_offset = 0; - else - main_map->l_tls_firstbyte_offset = (ph->p_vaddr - & (ph->p_align - 1)); - main_map->l_tls_initimage_size = ph->p_filesz; - main_map->l_tls_initimage = (void *) ph->p_vaddr; - - /* This image gets the ID one. */ - GL(dl_tls_max_dtv_idx) = main_map->l_tls_modid = 1; - } - break; - - case PT_GNU_STACK: - GL(dl_stack_flags) = ph->p_flags; - break; - - case PT_GNU_RELRO: - main_map->l_relro_addr = ph->p_vaddr; - main_map->l_relro_size = ph->p_memsz; - break; - } - - /* Adjust the address of the TLS initialization image in case - the executable is actually an ET_DYN object. */ - if (main_map->l_tls_initimage != NULL) - main_map->l_tls_initimage - = (char *) main_map->l_tls_initimage + main_map->l_addr; - if (! main_map->l_map_end) - main_map->l_map_end = ~0; - if (! main_map->l_text_end) - main_map->l_text_end = ~0; - if (! GL(dl_rtld_map).l_libname && GL(dl_rtld_map).l_name) - { - /* We were invoked directly, so the program might not have a - PT_INTERP. */ - _dl_rtld_libname.name = GL(dl_rtld_map).l_name; - /* _dl_rtld_libname.next = NULL; Already zero. */ - GL(dl_rtld_map).l_libname = &_dl_rtld_libname; - } - else - assert (GL(dl_rtld_map).l_libname); /* How else did we get here? */ - - /* If the current libname is different from the SONAME, add the - latter as well. */ - if (GL(dl_rtld_map).l_info[DT_SONAME] != NULL - && strcmp (GL(dl_rtld_map).l_libname->name, - (const char *) D_PTR (&GL(dl_rtld_map), l_info[DT_STRTAB]) - + GL(dl_rtld_map).l_info[DT_SONAME]->d_un.d_val) != 0) - { - static struct libname_list newname; - newname.name = ((char *) D_PTR (&GL(dl_rtld_map), l_info[DT_STRTAB]) - + GL(dl_rtld_map).l_info[DT_SONAME]->d_un.d_ptr); - newname.next = NULL; - newname.dont_free = 1; - - assert (GL(dl_rtld_map).l_libname->next == NULL); - GL(dl_rtld_map).l_libname->next = &newname; - } - /* The ld.so must be relocated since otherwise loading audit modules - will fail since they reuse the very same ld.so. */ - assert (GL(dl_rtld_map).l_relocated); - - if (! rtld_is_main) - { - /* Extract the contents of the dynamic section for easy access. */ - elf_get_dynamic_info (main_map, NULL); - /* Set up our cache of pointers into the hash table. */ - _dl_setup_hash (main_map); - } - - if (__builtin_expect (mode, normal) == verify) - { - /* We were called just to verify that this is a dynamic - executable using us as the program interpreter. Exit with an - error if we were not able to load the binary or no interpreter - is specified (i.e., this is no dynamically linked binary. */ - if (main_map->l_ld == NULL) - _exit (1); - - /* We allow here some platform specific code. */ -#ifdef DISTINGUISH_LIB_VERSIONS - DISTINGUISH_LIB_VERSIONS; -#endif - _exit (has_interp ? 0 : 2); - } - - struct link_map **first_preload = &GL(dl_rtld_map).l_next; - /* Set up the data structures for the system-supplied DSO early, - so they can influence _dl_init_paths. */ - setup_vdso (main_map, &first_preload); - -#ifdef DL_SYSDEP_OSCHECK - DL_SYSDEP_OSCHECK (_dl_fatal_printf); -#endif - - /* Initialize the data structures for the search paths for shared - objects. */ - _dl_init_paths (library_path); - - /* Initialize _r_debug. */ - struct r_debug *r = _dl_debug_initialize (GL(dl_rtld_map).l_addr, - LM_ID_BASE); - r->r_state = RT_CONSISTENT; - - /* Put the link_map for ourselves on the chain so it can be found by - name. Note that at this point the global chain of link maps contains - exactly one element, which is pointed to by dl_loaded. */ - if (! GL(dl_rtld_map).l_name) - /* If not invoked directly, the dynamic linker shared object file was - found by the PT_INTERP name. */ - GL(dl_rtld_map).l_name = (char *) GL(dl_rtld_map).l_libname->name; - GL(dl_rtld_map).l_type = lt_library; - main_map->l_next = &GL(dl_rtld_map); - GL(dl_rtld_map).l_prev = main_map; - ++GL(dl_ns)[LM_ID_BASE]._ns_nloaded; - ++GL(dl_load_adds); - - /* If LD_USE_LOAD_BIAS env variable has not been seen, default - to not using bias for non-prelinked PIEs and libraries - and using it for executables or prelinked PIEs or libraries. */ - if (GLRO(dl_use_load_bias) == (ElfW(Addr)) -2) - GLRO(dl_use_load_bias) = main_map->l_addr == 0 ? -1 : 0; - - /* Set up the program header information for the dynamic linker - itself. It is needed in the dl_iterate_phdr callbacks. */ - const ElfW(Ehdr) *rtld_ehdr; - - /* Starting from binutils-2.23, the linker will define the magic symbol - __ehdr_start to point to our own ELF header if it is visible in a - segment that also includes the phdrs. If that's not available, we use - the old method that assumes the beginning of the file is part of the - lowest-addressed PT_LOAD segment. */ -#ifdef HAVE_EHDR_START - extern const ElfW(Ehdr) __ehdr_start __attribute__ ((visibility ("hidden"))); - rtld_ehdr = &__ehdr_start; -#else - rtld_ehdr = (void *) GL(dl_rtld_map).l_map_start; -#endif - assert (rtld_ehdr->e_ehsize == sizeof *rtld_ehdr); - assert (rtld_ehdr->e_phentsize == sizeof (ElfW(Phdr))); - - const ElfW(Phdr) *rtld_phdr = (const void *) rtld_ehdr + rtld_ehdr->e_phoff; - - GL(dl_rtld_map).l_phdr = rtld_phdr; - GL(dl_rtld_map).l_phnum = rtld_ehdr->e_phnum; - - - /* PT_GNU_RELRO is usually the last phdr. */ - size_t cnt = rtld_ehdr->e_phnum; - while (cnt-- > 0) - if (rtld_phdr[cnt].p_type == PT_GNU_RELRO) - { - GL(dl_rtld_map).l_relro_addr = rtld_phdr[cnt].p_vaddr; - GL(dl_rtld_map).l_relro_size = rtld_phdr[cnt].p_memsz; - break; - } - - /* Add the dynamic linker to the TLS list if it also uses TLS. */ - if (GL(dl_rtld_map).l_tls_blocksize != 0) - /* Assign a module ID. Do this before loading any audit modules. */ - GL(dl_rtld_map).l_tls_modid = _dl_next_tls_modid (); - - /* If we have auditing DSOs to load, do it now. */ - if (__glibc_unlikely (audit_list != NULL)) - { - /* Iterate over all entries in the list. The order is important. */ - struct audit_ifaces *last_audit = NULL; - struct audit_list *al = audit_list->next; - - /* Since we start using the auditing DSOs right away we need to - initialize the data structures now. */ - tcbp = init_tls (); - - /* Initialize security features. We need to do it this early - since otherwise the constructors of the audit libraries will - use different values (especially the pointer guard) and will - fail later on. */ - security_init (); - - do - { - int tls_idx = GL(dl_tls_max_dtv_idx); - - /* Now it is time to determine the layout of the static TLS - block and allocate it for the initial thread. Note that we - always allocate the static block, we never defer it even if - no DF_STATIC_TLS bit is set. The reason is that we know - glibc will use the static model. */ - struct dlmopen_args dlmargs; - dlmargs.fname = al->name; - dlmargs.map = NULL; - - const char *objname; - const char *err_str = NULL; - bool malloced; - (void) _dl_catch_error (&objname, &err_str, &malloced, dlmopen_doit, - &dlmargs); - if (__glibc_unlikely (err_str != NULL)) - { - not_loaded: - _dl_error_printf ("\ -ERROR: ld.so: object '%s' cannot be loaded as audit interface: %s; ignored.\n", - al->name, err_str); - if (malloced) - free ((char *) err_str); - } - else - { - struct lookup_args largs; - largs.name = "la_version"; - largs.map = dlmargs.map; - - /* Check whether the interface version matches. */ - (void) _dl_catch_error (&objname, &err_str, &malloced, - lookup_doit, &largs); - - unsigned int (*laversion) (unsigned int); - unsigned int lav; - if (err_str == NULL - && (laversion = largs.result) != NULL - && (lav = laversion (LAV_CURRENT)) > 0 - && lav <= LAV_CURRENT) - { - /* Allocate structure for the callback function pointers. - This call can never fail. */ - union - { - struct audit_ifaces ifaces; -#define naudit_ifaces 8 - void (*fptr[naudit_ifaces]) (void); - } *newp = malloc (sizeof (*newp)); - - /* Names of the auditing interfaces. All in one - long string. */ - static const char audit_iface_names[] = - "la_activity\0" - "la_objsearch\0" - "la_objopen\0" - "la_preinit\0" -#if __ELF_NATIVE_CLASS == 32 - "la_symbind32\0" -#elif __ELF_NATIVE_CLASS == 64 - "la_symbind64\0" -#else -# error "__ELF_NATIVE_CLASS must be defined" -#endif -#define STRING(s) __STRING (s) - "la_" STRING (ARCH_LA_PLTENTER) "\0" - "la_" STRING (ARCH_LA_PLTEXIT) "\0" - "la_objclose\0"; - unsigned int cnt = 0; - const char *cp = audit_iface_names; - do - { - largs.name = cp; - (void) _dl_catch_error (&objname, &err_str, &malloced, - lookup_doit, &largs); - - /* Store the pointer. */ - if (err_str == NULL && largs.result != NULL) - { - newp->fptr[cnt] = largs.result; - - /* The dynamic linker link map is statically - allocated, initialize the data now. */ - GL(dl_rtld_map).l_audit[cnt].cookie - = (intptr_t) &GL(dl_rtld_map); - } - else - newp->fptr[cnt] = NULL; - ++cnt; - - cp = (char *) rawmemchr (cp, '\0') + 1; - } - while (*cp != '\0'); - assert (cnt == naudit_ifaces); - - /* Now append the new auditing interface to the list. */ - newp->ifaces.next = NULL; - if (last_audit == NULL) - last_audit = GLRO(dl_audit) = &newp->ifaces; - else - last_audit = last_audit->next = &newp->ifaces; - ++GLRO(dl_naudit); - - /* Mark the DSO as being used for auditing. */ - dlmargs.map->l_auditing = 1; - } - else - { - /* We cannot use the DSO, it does not have the - appropriate interfaces or it expects something - more recent. */ -#ifndef NDEBUG - Lmid_t ns = dlmargs.map->l_ns; -#endif - _dl_close (dlmargs.map); - - /* Make sure the namespace has been cleared entirely. */ - assert (GL(dl_ns)[ns]._ns_loaded == NULL); - assert (GL(dl_ns)[ns]._ns_nloaded == 0); - - GL(dl_tls_max_dtv_idx) = tls_idx; - goto not_loaded; - } - } - - al = al->next; - } - while (al != audit_list->next); - - /* If we have any auditing modules, announce that we already - have two objects loaded. */ - if (__glibc_unlikely (GLRO(dl_naudit) > 0)) - { - struct link_map *ls[2] = { main_map, &GL(dl_rtld_map) }; - - for (unsigned int outer = 0; outer < 2; ++outer) - { - struct audit_ifaces *afct = GLRO(dl_audit); - for (unsigned int cnt = 0; cnt < GLRO(dl_naudit); ++cnt) - { - if (afct->objopen != NULL) - { - ls[outer]->l_audit[cnt].bindflags - = afct->objopen (ls[outer], LM_ID_BASE, - &ls[outer]->l_audit[cnt].cookie); - - ls[outer]->l_audit_any_plt - |= ls[outer]->l_audit[cnt].bindflags != 0; - } - - afct = afct->next; - } - } - } - } - - /* Keep track of the currently loaded modules to count how many - non-audit modules which use TLS are loaded. */ - size_t count_modids = _dl_count_modids (); - - /* Set up debugging before the debugger is notified for the first time. */ -#ifdef ELF_MACHINE_DEBUG_SETUP - /* Some machines (e.g. MIPS) don't use DT_DEBUG in this way. */ - ELF_MACHINE_DEBUG_SETUP (main_map, r); - ELF_MACHINE_DEBUG_SETUP (&GL(dl_rtld_map), r); -#else - if (main_map->l_info[DT_DEBUG] != NULL) - /* There is a DT_DEBUG entry in the dynamic section. Fill it in - with the run-time address of the r_debug structure */ - main_map->l_info[DT_DEBUG]->d_un.d_ptr = (ElfW(Addr)) r; - - /* Fill in the pointer in the dynamic linker's own dynamic section, in - case you run gdb on the dynamic linker directly. */ - if (GL(dl_rtld_map).l_info[DT_DEBUG] != NULL) - GL(dl_rtld_map).l_info[DT_DEBUG]->d_un.d_ptr = (ElfW(Addr)) r; -#endif - - /* We start adding objects. */ - r->r_state = RT_ADD; - _dl_debug_state (); - LIBC_PROBE (init_start, 2, LM_ID_BASE, r); - - /* Auditing checkpoint: we are ready to signal that the initial map - is being constructed. */ - if (__glibc_unlikely (GLRO(dl_naudit) > 0)) - { - struct audit_ifaces *afct = GLRO(dl_audit); - for (unsigned int cnt = 0; cnt < GLRO(dl_naudit); ++cnt) - { - if (afct->activity != NULL) - afct->activity (&main_map->l_audit[cnt].cookie, LA_ACT_ADD); - - afct = afct->next; - } - } - - /* We have two ways to specify objects to preload: via environment - variable and via the file /etc/ld.so.preload. The latter can also - be used when security is enabled. */ - assert (*first_preload == NULL); - struct link_map **preloads = NULL; - unsigned int npreloads = 0; - - if (__glibc_unlikely (preloadlist != NULL)) - { - /* The LD_PRELOAD environment variable gives list of libraries - separated by white space or colons that are loaded before the - executable's dependencies and prepended to the global scope - list. If the binary is running setuid all elements - containing a '/' are ignored since it is insecure. */ - char *list = strdupa (preloadlist); - char *p; - - HP_TIMING_NOW (start); - - /* Prevent optimizing strsep. Speed is not important here. */ - while ((p = (strsep) (&list, " :")) != NULL) - if (p[0] != '\0' - && (__builtin_expect (! __libc_enable_secure, 1) - || strchr (p, '/') == NULL)) - npreloads += do_preload (p, main_map, "LD_PRELOAD"); - - HP_TIMING_NOW (stop); - HP_TIMING_DIFF (diff, start, stop); - HP_TIMING_ACCUM_NT (load_time, diff); - } - - /* There usually is no ld.so.preload file, it should only be used - for emergencies and testing. So the open call etc should usually - fail. Using access() on a non-existing file is faster than using - open(). So we do this first. If it succeeds we do almost twice - the work but this does not matter, since it is not for production - use. */ - static const char preload_file[] = "/etc/ld.so.preload"; - if (__glibc_unlikely (__access (preload_file, R_OK) == 0)) - { - /* Read the contents of the file. */ - file = _dl_sysdep_read_whole_file (preload_file, &file_size, - PROT_READ | PROT_WRITE); - if (__glibc_unlikely (file != MAP_FAILED)) - { - /* Parse the file. It contains names of libraries to be loaded, - separated by white spaces or `:'. It may also contain - comments introduced by `#'. */ - char *problem; - char *runp; - size_t rest; - - /* Eliminate comments. */ - runp = file; - rest = file_size; - while (rest > 0) - { - char *comment = memchr (runp, '#', rest); - if (comment == NULL) - break; - - rest -= comment - runp; - do - *comment = ' '; - while (--rest > 0 && *++comment != '\n'); - } - - /* We have one problematic case: if we have a name at the end of - the file without a trailing terminating characters, we cannot - place the \0. Handle the case separately. */ - if (file[file_size - 1] != ' ' && file[file_size - 1] != '\t' - && file[file_size - 1] != '\n' && file[file_size - 1] != ':') - { - problem = &file[file_size]; - while (problem > file && problem[-1] != ' ' - && problem[-1] != '\t' - && problem[-1] != '\n' && problem[-1] != ':') - --problem; - - if (problem > file) - problem[-1] = '\0'; - } - else - { - problem = NULL; - file[file_size - 1] = '\0'; - } - - HP_TIMING_NOW (start); - - if (file != problem) - { - char *p; - runp = file; - while ((p = strsep (&runp, ": \t\n")) != NULL) - if (p[0] != '\0') - npreloads += do_preload (p, main_map, preload_file); - } - - if (problem != NULL) - { - char *p = strndupa (problem, file_size - (problem - file)); - - npreloads += do_preload (p, main_map, preload_file); - } - - HP_TIMING_NOW (stop); - HP_TIMING_DIFF (diff, start, stop); - HP_TIMING_ACCUM_NT (load_time, diff); - - /* We don't need the file anymore. */ - __munmap (file, file_size); - } - } - - if (__glibc_unlikely (*first_preload != NULL)) - { - /* Set up PRELOADS with a vector of the preloaded libraries. */ - struct link_map *l = *first_preload; - preloads = __alloca (npreloads * sizeof preloads[0]); - i = 0; - do - { - preloads[i++] = l; - l = l->l_next; - } while (l); - assert (i == npreloads); - } - - /* Load all the libraries specified by DT_NEEDED entries. If LD_PRELOAD - specified some libraries to load, these are inserted before the actual - dependencies in the executable's searchlist for symbol resolution. */ - HP_TIMING_NOW (start); - _dl_map_object_deps (main_map, preloads, npreloads, mode == trace, 0); - HP_TIMING_NOW (stop); - HP_TIMING_DIFF (diff, start, stop); - HP_TIMING_ACCUM_NT (load_time, diff); - - /* Mark all objects as being in the global scope. */ - for (i = main_map->l_searchlist.r_nlist; i > 0; ) - main_map->l_searchlist.r_list[--i]->l_global = 1; - - /* Remove _dl_rtld_map from the chain. */ - GL(dl_rtld_map).l_prev->l_next = GL(dl_rtld_map).l_next; - if (GL(dl_rtld_map).l_next != NULL) - GL(dl_rtld_map).l_next->l_prev = GL(dl_rtld_map).l_prev; - - for (i = 1; i < main_map->l_searchlist.r_nlist; ++i) - if (main_map->l_searchlist.r_list[i] == &GL(dl_rtld_map)) - break; - - bool rtld_multiple_ref = false; - if (__glibc_likely (i < main_map->l_searchlist.r_nlist)) - { - /* Some DT_NEEDED entry referred to the interpreter object itself, so - put it back in the list of visible objects. We insert it into the - chain in symbol search order because gdb uses the chain's order as - its symbol search order. */ - rtld_multiple_ref = true; - - GL(dl_rtld_map).l_prev = main_map->l_searchlist.r_list[i - 1]; - if (__builtin_expect (mode, normal) == normal) - { - GL(dl_rtld_map).l_next = (i + 1 < main_map->l_searchlist.r_nlist - ? main_map->l_searchlist.r_list[i + 1] - : NULL); -#ifdef NEED_DL_SYSINFO_DSO - if (GLRO(dl_sysinfo_map) != NULL - && GL(dl_rtld_map).l_prev->l_next == GLRO(dl_sysinfo_map) - && GL(dl_rtld_map).l_next != GLRO(dl_sysinfo_map)) - GL(dl_rtld_map).l_prev = GLRO(dl_sysinfo_map); -#endif - } - else - /* In trace mode there might be an invisible object (which we - could not find) after the previous one in the search list. - In this case it doesn't matter much where we put the - interpreter object, so we just initialize the list pointer so - that the assertion below holds. */ - GL(dl_rtld_map).l_next = GL(dl_rtld_map).l_prev->l_next; - - assert (GL(dl_rtld_map).l_prev->l_next == GL(dl_rtld_map).l_next); - GL(dl_rtld_map).l_prev->l_next = &GL(dl_rtld_map); - if (GL(dl_rtld_map).l_next != NULL) - { - assert (GL(dl_rtld_map).l_next->l_prev == GL(dl_rtld_map).l_prev); - GL(dl_rtld_map).l_next->l_prev = &GL(dl_rtld_map); - } - } - - /* Now let us see whether all libraries are available in the - versions we need. */ - { - struct version_check_args args; - args.doexit = mode == normal; - args.dotrace = mode == trace; - _dl_receive_error (print_missing_version, version_check_doit, &args); - } - - /* We do not initialize any of the TLS functionality unless any of the - initial modules uses TLS. This makes dynamic loading of modules with - TLS impossible, but to support it requires either eagerly doing setup - now or lazily doing it later. Doing it now makes us incompatible with - an old kernel that can't perform TLS_INIT_TP, even if no TLS is ever - used. Trying to do it lazily is too hairy to try when there could be - multiple threads (from a non-TLS-using libpthread). */ - bool was_tls_init_tp_called = tls_init_tp_called; - if (tcbp == NULL) - tcbp = init_tls (); - - if (__glibc_likely (audit_list == NULL)) - /* Initialize security features. But only if we have not done it - earlier. */ - security_init (); - - if (__builtin_expect (mode, normal) != normal) - { - /* We were run just to list the shared libraries. It is - important that we do this before real relocation, because the - functions we call below for output may no longer work properly - after relocation. */ - struct link_map *l; - - if (GLRO(dl_debug_mask) & DL_DEBUG_PRELINK) - { - struct r_scope_elem *scope = &main_map->l_searchlist; - - for (i = 0; i < scope->r_nlist; i++) - { - l = scope->r_list [i]; - if (l->l_faked) - { - _dl_printf ("\t%s => not found\n", l->l_libname->name); - continue; - } - if (_dl_name_match_p (GLRO(dl_trace_prelink), l)) - GLRO(dl_trace_prelink_map) = l; - _dl_printf ("\t%s => %s (0x%0*Zx, 0x%0*Zx)", - DSO_FILENAME (l->l_libname->name), - DSO_FILENAME (l->l_name), - (int) sizeof l->l_map_start * 2, - (size_t) l->l_map_start, - (int) sizeof l->l_addr * 2, - (size_t) l->l_addr); - - if (l->l_tls_modid) - _dl_printf (" TLS(0x%Zx, 0x%0*Zx)\n", l->l_tls_modid, - (int) sizeof l->l_tls_offset * 2, - (size_t) l->l_tls_offset); - else - _dl_printf ("\n"); - } - } - else if (GLRO(dl_debug_mask) & DL_DEBUG_UNUSED) - { - /* Look through the dependencies of the main executable - and determine which of them is not actually - required. */ - struct link_map *l = main_map; - - /* Relocate the main executable. */ - struct relocate_args args = { .l = l, - .reloc_mode = ((GLRO(dl_lazy) - ? RTLD_LAZY : 0) - | __RTLD_NOIFUNC) }; - _dl_receive_error (print_unresolved, relocate_doit, &args); - - /* This loop depends on the dependencies of the executable to - correspond in number and order to the DT_NEEDED entries. */ - ElfW(Dyn) *dyn = main_map->l_ld; - bool first = true; - while (dyn->d_tag != DT_NULL) - { - if (dyn->d_tag == DT_NEEDED) - { - l = l->l_next; -#ifdef NEED_DL_SYSINFO_DSO - /* Skip the VDSO since it's not part of the list - of objects we brought in via DT_NEEDED entries. */ - if (l == GLRO(dl_sysinfo_map)) - l = l->l_next; -#endif - if (!l->l_used) - { - if (first) - { - _dl_printf ("Unused direct dependencies:\n"); - first = false; - } - - _dl_printf ("\t%s\n", l->l_name); - } - } - - ++dyn; - } - - _exit (first != true); - } - else if (! main_map->l_info[DT_NEEDED]) - _dl_printf ("\tstatically linked\n"); - else - { - for (l = main_map->l_next; l; l = l->l_next) - if (l->l_faked) - /* The library was not found. */ - _dl_printf ("\t%s => not found\n", l->l_libname->name); - else if (strcmp (l->l_libname->name, l->l_name) == 0) - _dl_printf ("\t%s (0x%0*Zx)\n", l->l_libname->name, - (int) sizeof l->l_map_start * 2, - (size_t) l->l_map_start); - else - _dl_printf ("\t%s => %s (0x%0*Zx)\n", l->l_libname->name, - l->l_name, (int) sizeof l->l_map_start * 2, - (size_t) l->l_map_start); - } - - if (__builtin_expect (mode, trace) != trace) - for (i = 1; i < (unsigned int) _dl_argc; ++i) - { - const ElfW(Sym) *ref = NULL; - ElfW(Addr) loadbase; - lookup_t result; - - result = _dl_lookup_symbol_x (_dl_argv[i], main_map, - &ref, main_map->l_scope, - NULL, ELF_RTYPE_CLASS_PLT, - DL_LOOKUP_ADD_DEPENDENCY, NULL); - - loadbase = LOOKUP_VALUE_ADDRESS (result); - - _dl_printf ("%s found at 0x%0*Zd in object at 0x%0*Zd\n", - _dl_argv[i], - (int) sizeof ref->st_value * 2, - (size_t) ref->st_value, - (int) sizeof loadbase * 2, (size_t) loadbase); - } - else - { - /* If LD_WARN is set, warn about undefined symbols. */ - if (GLRO(dl_lazy) >= 0 && GLRO(dl_verbose)) - { - /* We have to do symbol dependency testing. */ - struct relocate_args args; - unsigned int i; - - args.reloc_mode = ((GLRO(dl_lazy) ? RTLD_LAZY : 0) - | __RTLD_NOIFUNC); - - i = main_map->l_searchlist.r_nlist; - while (i-- > 0) - { - struct link_map *l = main_map->l_initfini[i]; - if (l != &GL(dl_rtld_map) && ! l->l_faked) - { - args.l = l; - _dl_receive_error (print_unresolved, relocate_doit, - &args); - } - } - - if ((GLRO(dl_debug_mask) & DL_DEBUG_PRELINK) - && rtld_multiple_ref) - { - /* Mark the link map as not yet relocated again. */ - GL(dl_rtld_map).l_relocated = 0; - _dl_relocate_object (&GL(dl_rtld_map), - main_map->l_scope, __RTLD_NOIFUNC, 0); - } - } -#define VERNEEDTAG (DT_NUM + DT_THISPROCNUM + DT_VERSIONTAGIDX (DT_VERNEED)) - if (version_info) - { - /* Print more information. This means here, print information - about the versions needed. */ - int first = 1; - struct link_map *map; - - for (map = main_map; map != NULL; map = map->l_next) - { - const char *strtab; - ElfW(Dyn) *dyn = map->l_info[VERNEEDTAG]; - ElfW(Verneed) *ent; - - if (dyn == NULL) - continue; - - strtab = (const void *) D_PTR (map, l_info[DT_STRTAB]); - ent = (ElfW(Verneed) *) (map->l_addr + dyn->d_un.d_ptr); - - if (first) - { - _dl_printf ("\n\tVersion information:\n"); - first = 0; - } - - _dl_printf ("\t%s:\n", DSO_FILENAME (map->l_name)); - - while (1) - { - ElfW(Vernaux) *aux; - struct link_map *needed; - - needed = find_needed (strtab + ent->vn_file); - aux = (ElfW(Vernaux) *) ((char *) ent + ent->vn_aux); - - while (1) - { - const char *fname = NULL; - - if (needed != NULL - && match_version (strtab + aux->vna_name, - needed)) - fname = needed->l_name; - - _dl_printf ("\t\t%s (%s) %s=> %s\n", - strtab + ent->vn_file, - strtab + aux->vna_name, - aux->vna_flags & VER_FLG_WEAK - ? "[WEAK] " : "", - fname ?: "not found"); - - if (aux->vna_next == 0) - /* No more symbols. */ - break; - - /* Next symbol. */ - aux = (ElfW(Vernaux) *) ((char *) aux - + aux->vna_next); - } - - if (ent->vn_next == 0) - /* No more dependencies. */ - break; - - /* Next dependency. */ - ent = (ElfW(Verneed) *) ((char *) ent + ent->vn_next); - } - } - } - } - - _exit (0); - } - - if (main_map->l_info[ADDRIDX (DT_GNU_LIBLIST)] - && ! __builtin_expect (GLRO(dl_profile) != NULL, 0) - && ! __builtin_expect (GLRO(dl_dynamic_weak), 0)) - { - ElfW(Lib) *liblist, *liblistend; - struct link_map **r_list, **r_listend, *l; - const char *strtab = (const void *) D_PTR (main_map, l_info[DT_STRTAB]); - - assert (main_map->l_info[VALIDX (DT_GNU_LIBLISTSZ)] != NULL); - liblist = (ElfW(Lib) *) - main_map->l_info[ADDRIDX (DT_GNU_LIBLIST)]->d_un.d_ptr; - liblistend = (ElfW(Lib) *) - ((char *) liblist + - main_map->l_info[VALIDX (DT_GNU_LIBLISTSZ)]->d_un.d_val); - r_list = main_map->l_searchlist.r_list; - r_listend = r_list + main_map->l_searchlist.r_nlist; - - for (; r_list < r_listend && liblist < liblistend; r_list++) - { - l = *r_list; - - if (l == main_map) - continue; - - /* If the library is not mapped where it should, fail. */ - if (l->l_addr) - break; - - /* Next, check if checksum matches. */ - if (l->l_info [VALIDX(DT_CHECKSUM)] == NULL - || l->l_info [VALIDX(DT_CHECKSUM)]->d_un.d_val - != liblist->l_checksum) - break; - - if (l->l_info [VALIDX(DT_GNU_PRELINKED)] == NULL - || l->l_info [VALIDX(DT_GNU_PRELINKED)]->d_un.d_val - != liblist->l_time_stamp) - break; - - if (! _dl_name_match_p (strtab + liblist->l_name, l)) - break; - - ++liblist; - } - - - if (r_list == r_listend && liblist == liblistend) - prelinked = true; - - if (__glibc_unlikely (GLRO(dl_debug_mask) & DL_DEBUG_LIBS)) - _dl_debug_printf ("\nprelink checking: %s\n", - prelinked ? "ok" : "failed"); - } - - - /* Now set up the variable which helps the assembler startup code. */ - GL(dl_ns)[LM_ID_BASE]._ns_main_searchlist = &main_map->l_searchlist; - - /* Save the information about the original global scope list since - we need it in the memory handling later. */ - GLRO(dl_initial_searchlist) = *GL(dl_ns)[LM_ID_BASE]._ns_main_searchlist; - - /* Remember the last search directory added at startup, now that - malloc will no longer be the one from dl-minimal.c. */ - GLRO(dl_init_all_dirs) = GL(dl_all_dirs); - - /* Print scope information. */ - if (__glibc_unlikely (GLRO(dl_debug_mask) & DL_DEBUG_SCOPES)) - { - _dl_debug_printf ("\nInitial object scopes\n"); - - for (struct link_map *l = main_map; l != NULL; l = l->l_next) - _dl_show_scope (l, 0); - } - - if (prelinked) - { - if (main_map->l_info [ADDRIDX (DT_GNU_CONFLICT)] != NULL) - { - ElfW(Rela) *conflict, *conflictend; -#ifndef HP_TIMING_NONAVAIL - hp_timing_t start; - hp_timing_t stop; -#endif - - HP_TIMING_NOW (start); - assert (main_map->l_info [VALIDX (DT_GNU_CONFLICTSZ)] != NULL); - conflict = (ElfW(Rela) *) - main_map->l_info [ADDRIDX (DT_GNU_CONFLICT)]->d_un.d_ptr; - conflictend = (ElfW(Rela) *) - ((char *) conflict - + main_map->l_info [VALIDX (DT_GNU_CONFLICTSZ)]->d_un.d_val); - _dl_resolve_conflicts (main_map, conflict, conflictend); - HP_TIMING_NOW (stop); - HP_TIMING_DIFF (relocate_time, start, stop); - } - - - /* Mark all the objects so we know they have been already relocated. */ - for (struct link_map *l = main_map; l != NULL; l = l->l_next) - { - l->l_relocated = 1; - if (l->l_relro_size) - _dl_protect_relro (l); - - /* Add object to slot information data if necessasy. */ - if (l->l_tls_blocksize != 0 && tls_init_tp_called) - _dl_add_to_slotinfo (l); - } - } - else - { - /* Now we have all the objects loaded. Relocate them all except for - the dynamic linker itself. We do this in reverse order so that copy - relocs of earlier objects overwrite the data written by later - objects. We do not re-relocate the dynamic linker itself in this - loop because that could result in the GOT entries for functions we - call being changed, and that would break us. It is safe to relocate - the dynamic linker out of order because it has no copy relocs (we - know that because it is self-contained). */ - - int consider_profiling = GLRO(dl_profile) != NULL; -#ifndef HP_TIMING_NONAVAIL - hp_timing_t start; - hp_timing_t stop; -#endif - - /* If we are profiling we also must do lazy reloaction. */ - GLRO(dl_lazy) |= consider_profiling; - - HP_TIMING_NOW (start); - unsigned i = main_map->l_searchlist.r_nlist; - while (i-- > 0) - { - struct link_map *l = main_map->l_initfini[i]; - - /* While we are at it, help the memory handling a bit. We have to - mark some data structures as allocated with the fake malloc() - implementation in ld.so. */ - struct libname_list *lnp = l->l_libname->next; - - while (__builtin_expect (lnp != NULL, 0)) - { - lnp->dont_free = 1; - lnp = lnp->next; - } - /* Also allocated with the fake malloc(). */ - l->l_free_initfini = 0; - - if (l != &GL(dl_rtld_map)) - _dl_relocate_object (l, l->l_scope, GLRO(dl_lazy) ? RTLD_LAZY : 0, - consider_profiling); - - /* Add object to slot information data if necessasy. */ - if (l->l_tls_blocksize != 0 && tls_init_tp_called) - _dl_add_to_slotinfo (l); - } - HP_TIMING_NOW (stop); - - HP_TIMING_DIFF (relocate_time, start, stop); - - /* Now enable profiling if needed. Like the previous call, - this has to go here because the calls it makes should use the - rtld versions of the functions (particularly calloc()), but it - needs to have _dl_profile_map set up by the relocator. */ - if (__glibc_unlikely (GL(dl_profile_map) != NULL)) - /* We must prepare the profiling. */ - _dl_start_profile (); - } - - if ((!was_tls_init_tp_called && GL(dl_tls_max_dtv_idx) > 0) - || count_modids != _dl_count_modids ()) - ++GL(dl_tls_generation); - - /* Now that we have completed relocation, the initializer data - for the TLS blocks has its final values and we can copy them - into the main thread's TLS area, which we allocated above. */ - _dl_allocate_tls_init (tcbp); - - /* And finally install it for the main thread. */ - if (! tls_init_tp_called) - { - const char *lossage = TLS_INIT_TP (tcbp); - if (__glibc_unlikely (lossage != NULL)) - _dl_fatal_printf ("cannot set up thread-local storage: %s\n", - lossage); - } - - /* Make sure no new search directories have been added. */ - assert (GLRO(dl_init_all_dirs) == GL(dl_all_dirs)); - - if (! prelinked && rtld_multiple_ref) - { - /* There was an explicit ref to the dynamic linker as a shared lib. - Re-relocate ourselves with user-controlled symbol definitions. - - We must do this after TLS initialization in case after this - re-relocation, we might call a user-supplied function - (e.g. calloc from _dl_relocate_object) that uses TLS data. */ - -#ifndef HP_TIMING_NONAVAIL - hp_timing_t start; - hp_timing_t stop; - hp_timing_t add; -#endif - - HP_TIMING_NOW (start); - /* Mark the link map as not yet relocated again. */ - GL(dl_rtld_map).l_relocated = 0; - _dl_relocate_object (&GL(dl_rtld_map), main_map->l_scope, 0, 0); - HP_TIMING_NOW (stop); - HP_TIMING_DIFF (add, start, stop); - HP_TIMING_ACCUM_NT (relocate_time, add); - } - - /* Do any necessary cleanups for the startup OS interface code. - We do these now so that no calls are made after rtld re-relocation - which might be resolved to different functions than we expect. - We cannot do this before relocating the other objects because - _dl_relocate_object might need to call `mprotect' for DT_TEXTREL. */ - _dl_sysdep_start_cleanup (); - -#ifdef SHARED - /* Auditing checkpoint: we have added all objects. */ - if (__glibc_unlikely (GLRO(dl_naudit) > 0)) - { - struct link_map *head = GL(dl_ns)[LM_ID_BASE]._ns_loaded; - /* Do not call the functions for any auditing object. */ - if (head->l_auditing == 0) - { - struct audit_ifaces *afct = GLRO(dl_audit); - for (unsigned int cnt = 0; cnt < GLRO(dl_naudit); ++cnt) - { - if (afct->activity != NULL) - afct->activity (&head->l_audit[cnt].cookie, LA_ACT_CONSISTENT); - - afct = afct->next; - } - } - } -#endif - - /* Notify the debugger all new objects are now ready to go. We must re-get - the address since by now the variable might be in another object. */ - r = _dl_debug_initialize (0, LM_ID_BASE); - r->r_state = RT_CONSISTENT; - _dl_debug_state (); - LIBC_PROBE (init_complete, 2, LM_ID_BASE, r); - -#if defined USE_LDCONFIG && !defined MAP_COPY - /* We must munmap() the cache file. */ - _dl_unload_cache (); -#endif - - /* Once we return, _dl_sysdep_start will invoke - the DT_INIT functions and then *USER_ENTRY. */ -} - -/* This is a little helper function for resolving symbols while - tracing the binary. */ -static void -print_unresolved (int errcode __attribute__ ((unused)), const char *objname, - const char *errstring) -{ - if (objname[0] == '\0') - objname = RTLD_PROGNAME; - _dl_error_printf ("%s (%s)\n", errstring, objname); -} - -/* This is a little helper function for resolving symbols while - tracing the binary. */ -static void -print_missing_version (int errcode __attribute__ ((unused)), - const char *objname, const char *errstring) -{ - _dl_error_printf ("%s: %s: %s\n", RTLD_PROGNAME, - objname, errstring); -} - -/* Nonzero if any of the debugging options is enabled. */ -static int any_debug attribute_relro; - -/* Process the string given as the parameter which explains which debugging - options are enabled. */ -static void -process_dl_debug (const char *dl_debug) -{ - /* When adding new entries make sure that the maximal length of a name - is correctly handled in the LD_DEBUG_HELP code below. */ - static const struct - { - unsigned char len; - const char name[10]; - const char helptext[41]; - unsigned short int mask; - } debopts[] = - { -#define LEN_AND_STR(str) sizeof (str) - 1, str - { LEN_AND_STR ("libs"), "display library search paths", - DL_DEBUG_LIBS | DL_DEBUG_IMPCALLS }, - { LEN_AND_STR ("reloc"), "display relocation processing", - DL_DEBUG_RELOC | DL_DEBUG_IMPCALLS }, - { LEN_AND_STR ("files"), "display progress for input file", - DL_DEBUG_FILES | DL_DEBUG_IMPCALLS }, - { LEN_AND_STR ("symbols"), "display symbol table processing", - DL_DEBUG_SYMBOLS | DL_DEBUG_IMPCALLS }, - { LEN_AND_STR ("bindings"), "display information about symbol binding", - DL_DEBUG_BINDINGS | DL_DEBUG_IMPCALLS }, - { LEN_AND_STR ("versions"), "display version dependencies", - DL_DEBUG_VERSIONS | DL_DEBUG_IMPCALLS }, - { LEN_AND_STR ("scopes"), "display scope information", - DL_DEBUG_SCOPES }, - { LEN_AND_STR ("all"), "all previous options combined", - DL_DEBUG_LIBS | DL_DEBUG_RELOC | DL_DEBUG_FILES | DL_DEBUG_SYMBOLS - | DL_DEBUG_BINDINGS | DL_DEBUG_VERSIONS | DL_DEBUG_IMPCALLS - | DL_DEBUG_SCOPES }, - { LEN_AND_STR ("statistics"), "display relocation statistics", - DL_DEBUG_STATISTICS }, - { LEN_AND_STR ("unused"), "determined unused DSOs", - DL_DEBUG_UNUSED }, - { LEN_AND_STR ("help"), "display this help message and exit", - DL_DEBUG_HELP }, - }; -#define ndebopts (sizeof (debopts) / sizeof (debopts[0])) - - /* Skip separating white spaces and commas. */ - while (*dl_debug != '\0') - { - if (*dl_debug != ' ' && *dl_debug != ',' && *dl_debug != ':') - { - size_t cnt; - size_t len = 1; - - while (dl_debug[len] != '\0' && dl_debug[len] != ' ' - && dl_debug[len] != ',' && dl_debug[len] != ':') - ++len; - - for (cnt = 0; cnt < ndebopts; ++cnt) - if (debopts[cnt].len == len - && memcmp (dl_debug, debopts[cnt].name, len) == 0) - { - GLRO(dl_debug_mask) |= debopts[cnt].mask; - any_debug = 1; - break; - } - - if (cnt == ndebopts) - { - /* Display a warning and skip everything until next - separator. */ - char *copy = strndupa (dl_debug, len); - _dl_error_printf ("\ -warning: debug option `%s' unknown; try LD_DEBUG=help\n", copy); - } - - dl_debug += len; - continue; - } - - ++dl_debug; - } - - if (GLRO(dl_debug_mask) & DL_DEBUG_UNUSED) - { - /* In order to get an accurate picture of whether a particular - DT_NEEDED entry is actually used we have to process both - the PLT and non-PLT relocation entries. */ - GLRO(dl_lazy) = 0; - } - - if (GLRO(dl_debug_mask) & DL_DEBUG_HELP) - { - size_t cnt; - - _dl_printf ("\ -Valid options for the LD_DEBUG environment variable are:\n\n"); - - for (cnt = 0; cnt < ndebopts; ++cnt) - _dl_printf (" %.*s%s%s\n", debopts[cnt].len, debopts[cnt].name, - " " + debopts[cnt].len - 3, - debopts[cnt].helptext); - - _dl_printf ("\n\ -To direct the debugging output into a file instead of standard output\n\ -a filename can be specified using the LD_DEBUG_OUTPUT environment variable.\n"); - _exit (0); - } -} - -static void -process_dl_audit (char *str) -{ - /* The parameter is a colon separated list of DSO names. */ - char *p; - - while ((p = (strsep) (&str, ":")) != NULL) - if (p[0] != '\0' - && (__builtin_expect (! __libc_enable_secure, 1) - || strchr (p, '/') == NULL)) - { - /* This is using the local malloc, not the system malloc. The - memory can never be freed. */ - struct audit_list *newp = malloc (sizeof (*newp)); - newp->name = p; - - if (audit_list == NULL) - audit_list = newp->next = newp; - else - { - newp->next = audit_list->next; - audit_list = audit_list->next = newp; - } - } -} - -/* Process all environments variables the dynamic linker must recognize. - Since all of them start with `LD_' we are a bit smarter while finding - all the entries. */ -extern char **_environ attribute_hidden; - - -static void -process_envvars (enum mode *modep) -{ - char **runp = _environ; - char *envline; - enum mode mode = normal; - char *debug_output = NULL; - - /* This is the default place for profiling data file. */ - GLRO(dl_profile_output) - = &"/var/tmp\0/var/profile"[__libc_enable_secure ? 9 : 0]; - - while ((envline = _dl_next_ld_env_entry (&runp)) != NULL) - { - size_t len = 0; - - while (envline[len] != '\0' && envline[len] != '=') - ++len; - - if (envline[len] != '=') - /* This is a "LD_" variable at the end of the string without - a '=' character. Ignore it since otherwise we will access - invalid memory below. */ - continue; - - switch (len) - { - case 4: - /* Warning level, verbose or not. */ - if (memcmp (envline, "WARN", 4) == 0) - GLRO(dl_verbose) = envline[5] != '\0'; - break; - - case 5: - /* Debugging of the dynamic linker? */ - if (memcmp (envline, "DEBUG", 5) == 0) - { - process_dl_debug (&envline[6]); - break; - } - if (memcmp (envline, "AUDIT", 5) == 0) - process_dl_audit (&envline[6]); - break; - - case 7: - /* Print information about versions. */ - if (memcmp (envline, "VERBOSE", 7) == 0) - { - version_info = envline[8] != '\0'; - break; - } - - /* List of objects to be preloaded. */ - if (memcmp (envline, "PRELOAD", 7) == 0) - { - preloadlist = &envline[8]; - break; - } - - /* Which shared object shall be profiled. */ - if (memcmp (envline, "PROFILE", 7) == 0 && envline[8] != '\0') - GLRO(dl_profile) = &envline[8]; - break; - - case 8: - /* Do we bind early? */ - if (memcmp (envline, "BIND_NOW", 8) == 0) - { - GLRO(dl_lazy) = envline[9] == '\0'; - break; - } - if (memcmp (envline, "BIND_NOT", 8) == 0) - GLRO(dl_bind_not) = envline[9] != '\0'; - break; - - case 9: - /* Test whether we want to see the content of the auxiliary - array passed up from the kernel. */ - if (!__libc_enable_secure - && memcmp (envline, "SHOW_AUXV", 9) == 0) - _dl_show_auxv (); - break; - -#if !HAVE_TUNABLES - case 10: - /* Mask for the important hardware capabilities. */ - if (!__libc_enable_secure - && memcmp (envline, "HWCAP_MASK", 10) == 0) - GLRO(dl_hwcap_mask) = __strtoul_internal (&envline[11], NULL, - 0, 0); - break; -#endif - - case 11: - /* Path where the binary is found. */ - if (!__libc_enable_secure - && memcmp (envline, "ORIGIN_PATH", 11) == 0) - GLRO(dl_origin_path) = &envline[12]; - break; - - case 12: - /* The library search path. */ - if (memcmp (envline, "LIBRARY_PATH", 12) == 0) - { - library_path = &envline[13]; - break; - } - - /* Where to place the profiling data file. */ - if (memcmp (envline, "DEBUG_OUTPUT", 12) == 0) - { - debug_output = &envline[13]; - break; - } - - if (!__libc_enable_secure - && memcmp (envline, "DYNAMIC_WEAK", 12) == 0) - GLRO(dl_dynamic_weak) = 1; - break; - - case 13: - /* We might have some extra environment variable with length 13 - to handle. */ -#ifdef EXTRA_LD_ENVVARS_13 - EXTRA_LD_ENVVARS_13 -#endif - if (!__libc_enable_secure - && memcmp (envline, "USE_LOAD_BIAS", 13) == 0) - { - GLRO(dl_use_load_bias) = envline[14] == '1' ? -1 : 0; - break; - } - break; - - case 14: - /* Where to place the profiling data file. */ - if (!__libc_enable_secure - && memcmp (envline, "PROFILE_OUTPUT", 14) == 0 - && envline[15] != '\0') - GLRO(dl_profile_output) = &envline[15]; - break; - - case 16: - /* The mode of the dynamic linker can be set. */ - if (memcmp (envline, "TRACE_PRELINKING", 16) == 0) - { - mode = trace; - GLRO(dl_verbose) = 1; - GLRO(dl_debug_mask) |= DL_DEBUG_PRELINK; - GLRO(dl_trace_prelink) = &envline[17]; - } - break; - - case 20: - /* The mode of the dynamic linker can be set. */ - if (memcmp (envline, "TRACE_LOADED_OBJECTS", 20) == 0) - mode = trace; - break; - - /* We might have some extra environment variable to handle. This - is tricky due to the pre-processing of the length of the name - in the switch statement here. The code here assumes that added - environment variables have a different length. */ -#ifdef EXTRA_LD_ENVVARS - EXTRA_LD_ENVVARS -#endif - } - } - - /* The caller wants this information. */ - *modep = mode; - - /* Extra security for SUID binaries. Remove all dangerous environment - variables. */ - if (__builtin_expect (__libc_enable_secure, 0)) - { - static const char unsecure_envvars[] = -#ifdef EXTRA_UNSECURE_ENVVARS - EXTRA_UNSECURE_ENVVARS -#endif - UNSECURE_ENVVARS; - const char *nextp; - - nextp = unsecure_envvars; - do - { - unsetenv (nextp); - /* We could use rawmemchr but this need not be fast. */ - nextp = (char *) (strchr) (nextp, '\0') + 1; - } - while (*nextp != '\0'); - - if (__access ("/etc/suid-debug", F_OK) != 0) - { -#if !HAVE_TUNABLES - unsetenv ("MALLOC_CHECK_"); -#endif - GLRO(dl_debug_mask) = 0; - } - - if (mode != normal) - _exit (5); - } - /* If we have to run the dynamic linker in debugging mode and the - LD_DEBUG_OUTPUT environment variable is given, we write the debug - messages to this file. */ - else if (any_debug && debug_output != NULL) - { - const int flags = O_WRONLY | O_APPEND | O_CREAT | O_NOFOLLOW; - size_t name_len = strlen (debug_output); - char buf[name_len + 12]; - char *startp; - - buf[name_len + 11] = '\0'; - startp = _itoa (__getpid (), &buf[name_len + 11], 10, 0); - *--startp = '.'; - startp = memcpy (startp - name_len, debug_output, name_len); - - GLRO(dl_debug_fd) = __open (startp, flags, DEFFILEMODE); - if (GLRO(dl_debug_fd) == -1) - /* We use standard output if opening the file failed. */ - GLRO(dl_debug_fd) = STDOUT_FILENO; - } -} - - -/* Print the various times we collected. */ -static void -__attribute ((noinline)) -print_statistics (hp_timing_t *rtld_total_timep) -{ -#ifndef HP_TIMING_NONAVAIL - char buf[200]; - char *cp; - char *wp; - - /* Total time rtld used. */ - if (HP_SMALL_TIMING_AVAIL) - { - HP_TIMING_PRINT (buf, sizeof (buf), *rtld_total_timep); - _dl_debug_printf ("\nruntime linker statistics:\n" - " total startup time in dynamic loader: %s\n", buf); - - /* Print relocation statistics. */ - char pbuf[30]; - HP_TIMING_PRINT (buf, sizeof (buf), relocate_time); - cp = _itoa ((1000ULL * relocate_time) / *rtld_total_timep, - pbuf + sizeof (pbuf), 10, 0); - wp = pbuf; - switch (pbuf + sizeof (pbuf) - cp) - { - case 3: - *wp++ = *cp++; - case 2: - *wp++ = *cp++; - case 1: - *wp++ = '.'; - *wp++ = *cp++; - } - *wp = '\0'; - _dl_debug_printf ("\ - time needed for relocation: %s (%s%%)\n", buf, pbuf); - } -#endif - - unsigned long int num_relative_relocations = 0; - for (Lmid_t ns = 0; ns < GL(dl_nns); ++ns) - { - if (GL(dl_ns)[ns]._ns_loaded == NULL) - continue; - - struct r_scope_elem *scope = &GL(dl_ns)[ns]._ns_loaded->l_searchlist; - - for (unsigned int i = 0; i < scope->r_nlist; i++) - { - struct link_map *l = scope->r_list [i]; - - if (l->l_addr != 0 && l->l_info[VERSYMIDX (DT_RELCOUNT)]) - num_relative_relocations - += l->l_info[VERSYMIDX (DT_RELCOUNT)]->d_un.d_val; -#ifndef ELF_MACHINE_REL_RELATIVE - /* Relative relocations are processed on these architectures if - library is loaded to different address than p_vaddr or - if not prelinked. */ - if ((l->l_addr != 0 || !l->l_info[VALIDX(DT_GNU_PRELINKED)]) - && l->l_info[VERSYMIDX (DT_RELACOUNT)]) -#else - /* On e.g. IA-64 or Alpha, relative relocations are processed - only if library is loaded to different address than p_vaddr. */ - if (l->l_addr != 0 && l->l_info[VERSYMIDX (DT_RELACOUNT)]) -#endif - num_relative_relocations - += l->l_info[VERSYMIDX (DT_RELACOUNT)]->d_un.d_val; - } - } - - _dl_debug_printf (" number of relocations: %lu\n" - " number of relocations from cache: %lu\n" - " number of relative relocations: %lu\n", - GL(dl_num_relocations), - GL(dl_num_cache_relocations), - num_relative_relocations); - -#ifndef HP_TIMING_NONAVAIL - /* Time spend while loading the object and the dependencies. */ - if (HP_SMALL_TIMING_AVAIL) - { - char pbuf[30]; - HP_TIMING_PRINT (buf, sizeof (buf), load_time); - cp = _itoa ((1000ULL * load_time) / *rtld_total_timep, - pbuf + sizeof (pbuf), 10, 0); - wp = pbuf; - switch (pbuf + sizeof (pbuf) - cp) - { - case 3: - *wp++ = *cp++; - case 2: - *wp++ = *cp++; - case 1: - *wp++ = '.'; - *wp++ = *cp++; - } - *wp = '\0'; - _dl_debug_printf ("\ - time needed to load objects: %s (%s%%)\n", - buf, pbuf); - } -#endif -} |