From ab1d521db39bf4371c7db96e8a0fcd4857ee70ed Mon Sep 17 00:00:00 2001 From: Roland McGrath Date: Thu, 7 Apr 2005 20:57:41 +0000 Subject: * sysdeps/unix/sysv/linux/dl-osinfo.h (_dl_discover_osversion) [(NEED_DL_SYSINFO || NEED_DL_SYSINFO_DSO) && SHARED]: Scan GLRO(dl_sysinfo_map) for PT_NOTE giving Linux kernel version, we can skip the uname call if it's there. * sysdeps/generic/dl-sysdep.c (_dl_sysdep_start): Don't use DL_SYSDEP_OSCHECK here. * elf/rtld.c (dl_main) [DL_SYSDEP_OSCHECK]: Do it here instead. * sysdeps/generic/ldsodefs.h (struct rtld_global_ro): Add _dl_sysinfo_map. * elf/rtld.c (dl_main): Don't call _dl_init_paths early in the rtld_is_main case. Call it unconditionally later. Move GLRO(dl_sysinfo_dso) handling earlier, before _dl_init_paths call. Initialize GLRO(dl_sysinfo_map). * elf/dl-load.c (open_path): Bail out if _dl_init_paths wasn't called. * sysdeps/generic/dl-sysdep.c (_DL_FIRST_EXTRA): New macro. (_dl_important_hwcaps) [(NEED_DL_SYSINFO || NEED_DL_SYSINFO_DSO) && SHARED]: Scan GLRO(dl_sysinfo_map) for PT_NOTE giving synthetic hwcap names and bit values. * elf/ldconfig.c (_DL_FIRST_EXTRA): New macro. (hwcap_extra): New static variable. (is_hwcap_platform): Check hwcap_extra for a matching name. Remove tls special case. (path_hwcap): Likewise. (parse_conf): Parse "hwcap" directive to define synthetic hwcap bits and their names, stored in hwcap_extra. (main) [USE_TLS]: Initialize final synthetic hwcap bit as "tls". * sysdeps/generic/ldsodefs.h (struct rtld_global_ro): Use uint64_t for _dl_hwcap and _dl_hwcap_mask. * sysdeps/generic/dl-sysdep.c (_dl_sysdep_start): Cast a_val for AT_HWCAP to unsigned long int. * elf/dl-support.c (_dl_aux_init): Likewise. (_dl_hwcap): Update defn. * elf/cache.c (print_entry): Pad hwcap value with 0s in diagnostic. * elf/ldconfig.c (search_dir): Likewise. --- elf/cache.c | 4 +- elf/dl-load.c | 5 ++ elf/dl-support.c | 6 +- elf/ldconfig.c | 80 ++++++++++++++++++++--- elf/rtld.c | 192 ++++++++++++++++++++++++++++--------------------------- 5 files changed, 179 insertions(+), 108 deletions(-) (limited to 'elf') diff --git a/elf/cache.c b/elf/cache.c index 22ad55c612..9324f3dc6c 100644 --- a/elf/cache.c +++ b/elf/cache.c @@ -1,4 +1,4 @@ -/* Copyright (C) 1999, 2000, 2001, 2002, 2003 +/* Copyright (C) 1999,2000,2001,2002,2003,2005 Free Software Foundation, Inc. This file is part of the GNU C Library. Contributed by Andreas Jaeger , 1999. @@ -99,7 +99,7 @@ print_entry (const char *lib, int flag, unsigned int osversion, break; } if (hwcap != 0) - printf (", hwcap: 0x%" PRIx64, hwcap); + printf (", hwcap: %#.16" PRIx64, hwcap); if (osversion != 0) { static const char *const abi_tag_os[] = diff --git a/elf/dl-load.c b/elf/dl-load.c index 2ca108ef69..d8b3a56d0d 100644 --- a/elf/dl-load.c +++ b/elf/dl-load.c @@ -1760,6 +1760,11 @@ open_path (const char *name, size_t namelen, int preloaded, const char *current_what = NULL; int any = 0; + if (__builtin_expect (dirs == NULL, 0)) + /* We're called before _dl_init_paths when loading the main executable + given on the command line when rtld is run directly. */ + return -1; + buf = alloca (max_dirnamelen + max_capstrlen + namelen); do { diff --git a/elf/dl-support.c b/elf/dl-support.c index b10dc90418..d145a7b44c 100644 --- a/elf/dl-support.c +++ b/elf/dl-support.c @@ -1,5 +1,5 @@ /* Support for dynamic linking code in static libc. - Copyright (C) 1996-2002, 2003, 2004 Free Software Foundation, Inc. + Copyright (C) 1996-2002, 2003, 2004, 2005 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 @@ -121,7 +121,7 @@ int _dl_correct_cache_id = _DL_CACHE_DEFAULT_ID; ElfW(Phdr) *_dl_phdr; size_t _dl_phnum; -unsigned long int _dl_hwcap __attribute__ ((nocommon)); +uint64_t _dl_hwcap __attribute__ ((nocommon)); /* Prevailing state of the stack, PF_X indicating it's executable. */ ElfW(Word) _dl_stack_flags = PF_R|PF_W|PF_X; @@ -179,7 +179,7 @@ _dl_aux_init (ElfW(auxv_t) *av) GL(dl_phnum) = av->a_un.a_val; break; case AT_HWCAP: - GLRO(dl_hwcap) = av->a_un.a_val; + GLRO(dl_hwcap) = (unsigned long int) av->a_un.a_val; break; #ifdef NEED_DL_SYSINFO case AT_SYSINFO: diff --git a/elf/ldconfig.c b/elf/ldconfig.c index 2502f854a6..6f840e0c82 100644 --- a/elf/ldconfig.c +++ b/elf/ldconfig.c @@ -44,6 +44,12 @@ #include "dl-procinfo.h" +#ifdef _DL_FIRST_PLATFORM +# define _DL_FIRST_EXTRA (_DL_FIRST_PLATFORM + _DL_PLATFORMS_COUNT) +#else +# define _DL_FIRST_EXTRA _DL_HWCAP_COUNT +#endif + #ifndef LD_SO_CONF # define LD_SO_CONF SYSCONFDIR "/ld.so.conf" #endif @@ -115,6 +121,9 @@ static const char *config_file; /* Mask to use for important hardware capabilities. */ static unsigned long int hwcap_mask = HWCAP_IMPORTANT; +/* Configuration-defined capabilities defined in kernel vDSOs. */ +static const char *hwcap_extra[64 - _DL_FIRST_EXTRA]; + /* Name and version of program. */ static void print_version (FILE *stream, struct argp_state *state); void (*argp_program_version_hook) (FILE *, struct argp_state *) @@ -165,10 +174,10 @@ is_hwcap_platform (const char *name) if (hwcap_idx != -1) return 1; -#ifdef USE_TLS - if (strcmp (name, "tls") == 0) - return 1; -#endif + for (hwcap_idx = _DL_FIRST_EXTRA; hwcap_idx < 64; ++hwcap_idx) + if (hwcap_extra[hwcap_idx - _DL_FIRST_EXTRA] != NULL + && !strcmp (name, hwcap_extra[hwcap_idx - _DL_FIRST_EXTRA])) + return 1; return 0; } @@ -203,11 +212,11 @@ path_hwcap (const char *path) h = _dl_string_platform (ptr + 1); if (h == (uint64_t) -1) { -#ifdef USE_TLS - if (strcmp (ptr + 1, "tls") == 0) - h = 63; - else -#endif + for (h = _DL_FIRST_EXTRA; h < 64; ++h) + if (hwcap_extra[h - _DL_FIRST_EXTRA] != NULL + && !strcmp (ptr + 1, hwcap_extra[h - _DL_FIRST_EXTRA])) + break; + if (h == 64) break; } } @@ -636,7 +645,7 @@ search_dir (const struct dir_entry *entry) if (opt_verbose) { if (hwcap != 0) - printf ("%s: (hwcap: 0x%" PRIx64 ")\n", entry->path, hwcap); + printf ("%s: (hwcap: %#.16" PRIx64 ")\n", entry->path, hwcap); else printf ("%s:\n", entry->path); } @@ -1017,6 +1026,53 @@ parse_conf (const char *filename, bool do_chroot) if (dir[0] != '\0') parse_conf_include (filename, lineno, do_chroot, dir); } + else if (!strncasecmp (cp, "hwcap", 5) && isblank (cp[5])) + { + cp += 6; + char *p, *name = NULL; + unsigned long int n = strtoul (cp, &cp, 0); + if (cp != NULL && isblank (*cp)) + while ((p = strsep (&cp, " \t")) != NULL) + if (p[0] != '\0') + { + if (name == NULL) + name = p; + else + { + name = NULL; + break; + } + } + if (name == NULL) + { + error (EXIT_FAILURE, 0, _("%s:%u: bad syntax in hwcap line"), + filename, lineno); + break; + } + if (n >= (64 - _DL_FIRST_EXTRA)) + error (EXIT_FAILURE, 0, + _("%s:%u: hwcap index %lu above maximum %u"), + filename, lineno, n, 64 - _DL_FIRST_EXTRA - 1); + if (hwcap_extra[n] == NULL) + { + for (unsigned long int h = 0; h < (64 - _DL_FIRST_EXTRA); ++h) + if (hwcap_extra[h] != NULL && !strcmp (name, hwcap_extra[h])) + error (EXIT_FAILURE, 0, + _("%s:%u: hwcap index %lu already defined as %s"), + filename, lineno, h, name); + hwcap_extra[n] = xstrdup (name); + } + else + { + if (strcmp (name, hwcap_extra[n])) + error (EXIT_FAILURE, 0, + _("%s:%u: hwcap index %lu already defined as %s"), + filename, lineno, n, hwcap_extra[n]); + if (opt_verbose) + error (0, 0, _("%s:%u: duplicate hwcap %lu %s"), + filename, lineno, n, name); + } + } else add_dir (cp); } @@ -1118,6 +1174,10 @@ main (int argc, char **argv) add_dir (argv[i]); } +#ifdef USE_TLS + hwcap_extra[63 - _DL_FIRST_EXTRA] = "tls"; +#endif + set_hwcap (); if (opt_chroot) 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 -- cgit 1.4.1