diff options
Diffstat (limited to 'elf')
| -rw-r--r-- | elf/Makefile | 2 | ||||
| -rw-r--r-- | elf/Versions | 4 | ||||
| -rw-r--r-- | elf/dl-load.c | 9 | ||||
| -rw-r--r-- | elf/dl-lookup_libc_early_init.c (renamed from elf/dl-call-libc-early-init.c) | 23 | ||||
| -rw-r--r-- | elf/dl-open.c | 4 | ||||
| -rw-r--r-- | elf/dl-version.c | 18 | ||||
| -rw-r--r-- | elf/libc-early-init.h | 21 | ||||
| -rw-r--r-- | elf/rtld.c | 12 |
8 files changed, 49 insertions, 44 deletions
diff --git a/elf/Makefile b/elf/Makefile index 3928a08..bc68150 100644 --- a/elf/Makefile +++ b/elf/Makefile @@ -52,7 +52,6 @@ routines = \ # The core dynamic linking functions are in libc for the static and # profiled libraries. dl-routines = \ - dl-call-libc-early-init \ dl-close \ dl-debug \ dl-debug-symbols \ @@ -65,6 +64,7 @@ dl-routines = \ dl-load \ dl-lookup \ dl-lookup-direct \ + dl-lookup_libc_early_init \ dl-minimal-malloc \ dl-misc \ dl-object \ diff --git a/elf/Versions b/elf/Versions index a9ff278..6260c0f 100644 --- a/elf/Versions +++ b/elf/Versions @@ -29,8 +29,8 @@ libc { __placeholder_only_for_empty_version_map; } GLIBC_PRIVATE { - # functions used in other libraries - __libc_early_init; + # A pattern is needed here because the suffix is dynamically generated. + __libc_early_init_*; # Internal error handling support. Interposes the functions in ld.so. _dl_signal_exception; _dl_catch_exception; diff --git a/elf/dl-load.c b/elf/dl-load.c index 1ad0868..00e08b5 100644 --- a/elf/dl-load.c +++ b/elf/dl-load.c @@ -31,7 +31,6 @@ #include <sys/param.h> #include <sys/stat.h> #include <sys/types.h> -#include <gnu/lib-names.h> /* Type for the buffer we put the ELF header and hopefully the program header. This buffer does not really have to be too large. In most @@ -1466,14 +1465,6 @@ cannot enable executable stack as shared object requires"); add_name_to_object (l, ((const char *) D_PTR (l, l_info[DT_STRTAB]) + l->l_info[DT_SONAME]->d_un.d_val)); - /* If we have newly loaded libc.so, update the namespace - description. */ - if (GL(dl_ns)[nsid].libc_map == NULL - && l->l_info[DT_SONAME] != NULL - && strcmp (((const char *) D_PTR (l, l_info[DT_STRTAB]) - + l->l_info[DT_SONAME]->d_un.d_val), LIBC_SO) == 0) - GL(dl_ns)[nsid].libc_map = l; - /* _dl_close can only eventually undo the module ID assignment (via remove_slotinfo) if this function returns a pointer to a link map. Therefore, delay this step until all possibilities for diff --git a/elf/dl-call-libc-early-init.c b/elf/dl-lookup_libc_early_init.c index ee9860e..64bc287 100644 --- a/elf/dl-call-libc-early-init.c +++ b/elf/dl-lookup_libc_early_init.c @@ -1,4 +1,4 @@ -/* Invoke the early initialization function in libc.so. +/* Find the address of the __libc_early_init function. Copyright (C) 2020-2022 Free Software Foundation, Inc. This file is part of the GNU C Library. @@ -16,26 +16,21 @@ License along with the GNU C Library; if not, see <https://www.gnu.org/licenses/>. */ -#include <assert.h> #include <ldsodefs.h> #include <libc-early-init.h> #include <link.h> #include <stddef.h> -void -_dl_call_libc_early_init (struct link_map *libc_map, _Bool initial) +__typeof (__libc_early_init) * +_dl_lookup_libc_early_init (struct link_map *libc_map) { - /* There is nothing to do if we did not actually load libc.so. */ - if (libc_map == NULL) - return; - const ElfW(Sym) *sym - = _dl_lookup_direct (libc_map, "__libc_early_init", - 0x069682ac, /* dl_new_hash output. */ + = _dl_lookup_direct (libc_map, LIBC_EARLY_INIT_NAME_STRING, + LIBC_EARLY_INIT_GNU_HASH, "GLIBC_PRIVATE", 0x0963cf85); /* _dl_elf_hash output. */ - assert (sym != NULL); - __typeof (__libc_early_init) *early_init - = DL_SYMBOL_ADDRESS (libc_map, sym); - early_init (initial); + if (sym == NULL) + _dl_signal_error (0, libc_map->l_name, NULL, "\ +ld.so/libc.so mismatch detected (upgrade in progress?)"); + return DL_SYMBOL_ADDRESS (libc_map, sym); } diff --git a/elf/dl-open.c b/elf/dl-open.c index a23e659..dcc2413 100644 --- a/elf/dl-open.c +++ b/elf/dl-open.c @@ -760,8 +760,8 @@ dl_open_worker_begin (void *a) if (!args->libc_already_loaded) { /* dlopen cannot be used to load an initial libc by design. */ - struct link_map *libc_map = GL(dl_ns)[args->nsid].libc_map; - _dl_call_libc_early_init (libc_map, false); + if (GL(dl_ns)[args->nsid].libc_map != NULL) + GL(dl_ns)[args->nsid].libc_map_early_init (false); } args->worker_continue = true; diff --git a/elf/dl-version.c b/elf/dl-version.c index cda0889..d9ec44e 100644 --- a/elf/dl-version.c +++ b/elf/dl-version.c @@ -23,6 +23,8 @@ #include <string.h> #include <ldsodefs.h> #include <_itoa.h> +#include <gnu/lib-names.h> +#include <libc-early-init.h> #include <assert.h> @@ -359,6 +361,22 @@ _dl_check_map_versions (struct link_map *map, int verbose, int trace_mode) } } + /* Detect a libc.so loaded into this namespace. The + __libc_early_init lookup below means that we have to do this + after parsing the version data. */ + if (GL(dl_ns)[map->l_ns].libc_map == NULL + && map->l_info[DT_SONAME] != NULL + && strcmp (((const char *) D_PTR (map, l_info[DT_STRTAB]) + + map->l_info[DT_SONAME]->d_un.d_val), LIBC_SO) == 0) + { + /* Look up this symbol early to trigger a mismatch error before + relocation (which may call IFUNC resolvers, and those can + have an internal ABI dependency). */ + GL(dl_ns)[map->l_ns].libc_map_early_init + = _dl_lookup_libc_early_init (map); + GL(dl_ns)[map->l_ns].libc_map = map; + } + /* When there is a DT_VERNEED entry with libc.so on DT_NEEDED, issue an error if there is a DT_RELR entry without GLIBC_ABI_DT_RELR dependency. */ diff --git a/elf/libc-early-init.h b/elf/libc-early-init.h index a8edfad..ac8c204 100644 --- a/elf/libc-early-init.h +++ b/elf/libc-early-init.h @@ -19,12 +19,9 @@ #ifndef _LIBC_EARLY_INIT_H #define _LIBC_EARLY_INIT_H -struct link_map; +#include <libc_early_init_name.h> -/* If LIBC_MAP is not NULL, look up the __libc_early_init symbol in it - and call this function, with INITIAL as the argument. */ -void _dl_call_libc_early_init (struct link_map *libc_map, _Bool initial) - attribute_hidden; +struct link_map; /* In the shared case, this function is defined in libc.so and invoked from ld.so (or on the fist static dlopen) after complete relocation @@ -33,6 +30,18 @@ void _dl_call_libc_early_init (struct link_map *libc_map, _Bool initial) startup code. If INITIAL is true, the libc being initialized is the libc for the main program. INITIAL is false for libcs loaded for audit modules, dlmopen, and static dlopen. */ -void __libc_early_init (_Bool initial); +void __libc_early_init (_Bool initial) +#ifdef SHARED +/* Redirect to the actual implementation name. */ + __asm__ (LIBC_EARLY_INIT_NAME_STRING) +#endif + ; + +/* Attempts to find the appropriately named __libc_early_init function + in LIBC_MAP. On lookup failure, an exception is signaled, + indicating an ld.so/libc.so mismatch. */ +__typeof (__libc_early_init) *_dl_lookup_libc_early_init (struct link_map * + libc_map) + attribute_hidden; #endif /* _LIBC_EARLY_INIT_H */ @@ -1707,15 +1707,6 @@ dl_main (const ElfW(Phdr) *phdr, /* Extract the contents of the dynamic section for easy access. */ elf_get_dynamic_info (main_map, false, false); - /* If the main map is libc.so, update the base namespace to - refer to this map. If libc.so is loaded later, this happens - in _dl_map_object_from_fd. */ - if (main_map->l_info[DT_SONAME] != NULL - && (strcmp (((const char *) D_PTR (main_map, l_info[DT_STRTAB]) - + main_map->l_info[DT_SONAME]->d_un.d_val), LIBC_SO) - == 0)) - GL(dl_ns)[LM_ID_BASE].libc_map = main_map; - /* Set up our cache of pointers into the hash table. */ _dl_setup_hash (main_map); } @@ -2386,7 +2377,8 @@ dl_main (const ElfW(Phdr) *phdr, /* Relocation is complete. Perform early libc initialization. This is the initial libc, even if audit modules have been loaded with other libcs. */ - _dl_call_libc_early_init (GL(dl_ns)[LM_ID_BASE].libc_map, true); + if (GL(dl_ns)[LM_ID_BASE].libc_map != NULL) + GL(dl_ns)[LM_ID_BASE].libc_map_early_init (true); /* Do any necessary cleanups for the startup OS interface code. We do these now so that no calls are made after rtld re-relocation |