diff options
Diffstat (limited to 'elf/rtld.c')
| -rw-r--r-- | elf/rtld.c | 192 |
1 files changed, 99 insertions, 93 deletions
diff --git a/elf/rtld.c b/elf/rtld.c index a2ca24ec59..912d63519d 100644 --- a/elf/rtld.c +++ b/elf/rtld.c @@ -958,11 +958,6 @@ of this helper program; chances are you did not intend to run this program.\n\ --_dl_argc; ++INTUSE(_dl_argv); - /* Initialize the data structures for the search paths for shared - objects. */ - _dl_init_paths (library_path); - - /* 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 @@ -1229,10 +1224,98 @@ ld.so does not support TLS, but program uses it!\n"); _exit (has_interp ? 0 : 2); } - if (! rtld_is_main) - /* Initialize the data structures for the search paths for shared - objects. */ - _dl_init_paths (library_path); + struct link_map **first_preload = &GL(dl_rtld_map).l_next; +#if defined NEED_DL_SYSINFO || defined NEED_DL_SYSINFO_DSO + /* Set up the data structures for the system-supplied DSO early, + so they can influence _dl_init_paths. */ + if (GLRO(dl_sysinfo_dso) != NULL) + { + /* Do an abridged version of the work _dl_map_object_from_fd would do + to map in the object. It's already mapped and prelinked (and + better be, since it's read-only and so we couldn't relocate it). + We just want our data structures to describe it as if we had just + mapped and relocated it normally. */ + struct link_map *l = _dl_new_object ((char *) "", "", lt_library, NULL, + 0, LM_ID_BASE); + if (__builtin_expect (l != NULL, 1)) + { + static ElfW(Dyn) dyn_temp[DL_RO_DYN_TEMP_CNT] attribute_relro; + + l->l_phdr = ((const void *) GLRO(dl_sysinfo_dso) + + GLRO(dl_sysinfo_dso)->e_phoff); + l->l_phnum = GLRO(dl_sysinfo_dso)->e_phnum; + for (uint_fast16_t i = 0; i < l->l_phnum; ++i) + { + const ElfW(Phdr) *const ph = &l->l_phdr[i]; + if (ph->p_type == PT_DYNAMIC) + { + l->l_ld = (void *) ph->p_vaddr; + l->l_ldnum = ph->p_memsz / sizeof (ElfW(Dyn)); + } + else if (ph->p_type == PT_LOAD) + { + if (! l->l_addr) + l->l_addr = ph->p_vaddr; + if (ph->p_vaddr + ph->p_memsz >= l->l_map_end) + l->l_map_end = ph->p_vaddr + ph->p_memsz; + if ((ph->p_flags & PF_X) + && ph->p_vaddr + ph->p_memsz >= l->l_text_end) + l->l_text_end = ph->p_vaddr + ph->p_memsz; + } + else + /* There must be no TLS segment. */ + assert (ph->p_type != PT_TLS); + } + l->l_map_start = (ElfW(Addr)) GLRO(dl_sysinfo_dso); + l->l_addr = l->l_map_start - l->l_addr; + l->l_map_end += l->l_addr; + l->l_text_end += l->l_addr; + l->l_ld = (void *) ((ElfW(Addr)) l->l_ld + l->l_addr); + elf_get_dynamic_info (l, dyn_temp); + _dl_setup_hash (l); + l->l_relocated = 1; + + /* Now that we have the info handy, use the DSO image's soname + so this object can be looked up by name. Note that we do not + set l_name here. That field gives the file name of the DSO, + and this DSO is not associated with any file. */ + if (l->l_info[DT_SONAME] != NULL) + { + /* Work around a kernel problem. The kernel cannot handle + addresses in the vsyscall DSO pages in writev() calls. */ + const char *dsoname = ((char *) D_PTR (l, l_info[DT_STRTAB]) + + l->l_info[DT_SONAME]->d_un.d_val); + size_t len = strlen (dsoname); + char *copy = malloc (len); + if (copy == NULL) + _dl_fatal_printf ("out of memory\n"); + l->l_libname->name = memcpy (copy, dsoname, len); + } + + /* Rearrange the list so this DSO appears after rtld_map. */ + assert (l->l_next == NULL); + assert (l->l_prev == main_map); + GL(dl_rtld_map).l_next = l; + l->l_prev = &GL(dl_rtld_map); + first_preload = &l->l_next; + + /* We have a prelinked DSO preloaded by the system. */ + GLRO(dl_sysinfo_map) = l; +# ifdef NEED_DL_SYSINFO + if (GLRO(dl_sysinfo) == DL_SYSINFO_DEFAULT) + GLRO(dl_sysinfo) = GLRO(dl_sysinfo_dso)->e_entry + l->l_addr; +# endif + } + } +#endif + +#ifdef DL_SYSDEP_OSCHECK + DL_SYSDEP_OSCHECK (dl_fatal); +#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, @@ -1477,7 +1560,7 @@ ERROR: ld.so: object '%s' cannot be loaded as audit interface: %s; ignored.\n", /* 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 (GL(dl_rtld_map).l_next == NULL); + assert (*first_preload == NULL); struct link_map **preloads = NULL; unsigned int npreloads = 0; @@ -1589,12 +1672,11 @@ ERROR: ld.so: object '%s' cannot be loaded as audit interface: %s; ignored.\n", } } - if (__builtin_expect (GL(dl_rtld_map).l_next != NULL, 0)) + if (__builtin_expect (*first_preload != NULL, 0)) { /* Set up PRELOADS with a vector of the preloaded libraries. */ - struct link_map *l; + struct link_map *l = *first_preload; preloads = __alloca (npreloads * sizeof preloads[0]); - l = GL(dl_rtld_map).l_next; /* End of the chain before preloads. */ i = 0; do { @@ -1604,82 +1686,6 @@ ERROR: ld.so: object '%s' cannot be loaded as audit interface: %s; ignored.\n", assert (i == npreloads); } -#if defined NEED_DL_SYSINFO || defined NEED_DL_SYSINFO_DSO - struct link_map *sysinfo_map = NULL; - if (GLRO(dl_sysinfo_dso) != NULL) - { - /* Do an abridged version of the work _dl_map_object_from_fd would do - to map in the object. It's already mapped and prelinked (and - better be, since it's read-only and so we couldn't relocate it). - We just want our data structures to describe it as if we had just - mapped and relocated it normally. */ - struct link_map *l = _dl_new_object ((char *) "", "", lt_library, NULL, - 0, LM_ID_BASE); - if (__builtin_expect (l != NULL, 1)) - { - static ElfW(Dyn) dyn_temp[DL_RO_DYN_TEMP_CNT] attribute_relro; - - l->l_phdr = ((const void *) GLRO(dl_sysinfo_dso) - + GLRO(dl_sysinfo_dso)->e_phoff); - l->l_phnum = GLRO(dl_sysinfo_dso)->e_phnum; - for (uint_fast16_t i = 0; i < l->l_phnum; ++i) - { - const ElfW(Phdr) *const ph = &l->l_phdr[i]; - if (ph->p_type == PT_DYNAMIC) - { - l->l_ld = (void *) ph->p_vaddr; - l->l_ldnum = ph->p_memsz / sizeof (ElfW(Dyn)); - } - else if (ph->p_type == PT_LOAD) - { - if (! l->l_addr) - l->l_addr = ph->p_vaddr; - if (ph->p_vaddr + ph->p_memsz >= l->l_map_end) - l->l_map_end = ph->p_vaddr + ph->p_memsz; - if ((ph->p_flags & PF_X) - && ph->p_vaddr + ph->p_memsz >= l->l_text_end) - l->l_text_end = ph->p_vaddr + ph->p_memsz; - } - else - /* There must be no TLS segment. */ - assert (ph->p_type != PT_TLS); - } - l->l_map_start = (ElfW(Addr)) GLRO(dl_sysinfo_dso); - l->l_addr = l->l_map_start - l->l_addr; - l->l_map_end += l->l_addr; - l->l_text_end += l->l_addr; - l->l_ld = (void *) ((ElfW(Addr)) l->l_ld + l->l_addr); - elf_get_dynamic_info (l, dyn_temp); - _dl_setup_hash (l); - l->l_relocated = 1; - - /* Now that we have the info handy, use the DSO image's soname - so this object can be looked up by name. Note that we do not - set l_name here. That field gives the file name of the DSO, - and this DSO is not associated with any file. */ - if (l->l_info[DT_SONAME] != NULL) - { - /* Work around a kernel problem. The kernel cannot handle - addresses in the vsyscall DSO pages in writev() calls. */ - const char *dsoname = ((char *) D_PTR (l, l_info[DT_STRTAB]) - + l->l_info[DT_SONAME]->d_un.d_val); - size_t len = strlen (dsoname); - char *copy = malloc (len); - if (copy == NULL) - _dl_fatal_printf ("out of memory\n"); - l->l_libname->name = memcpy (copy, dsoname, len); - } - - /* We have a prelinked DSO preloaded by the system. */ - sysinfo_map = l; -# ifdef NEED_DL_SYSINFO - if (GLRO(dl_sysinfo) == DL_SYSINFO_DEFAULT) - GLRO(dl_sysinfo) = GLRO(dl_sysinfo_dso)->e_entry + l->l_addr; -# endif - } - } -#endif - /* 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. */ @@ -1724,10 +1730,10 @@ ERROR: ld.so: object '%s' cannot be loaded as audit interface: %s; ignored.\n", ? main_map->l_searchlist.r_list[i + 1] : NULL); #if defined NEED_DL_SYSINFO || defined NEED_DL_SYSINFO_DSO - if (sysinfo_map != NULL - && GL(dl_rtld_map).l_prev->l_next == sysinfo_map - && GL(dl_rtld_map).l_next != sysinfo_map) - GL(dl_rtld_map).l_prev = sysinfo_map; + 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 |