diff options
Diffstat (limited to 'elf/rtld.c')
| -rw-r--r-- | elf/rtld.c | 116 |
1 files changed, 56 insertions, 60 deletions
diff --git a/elf/rtld.c b/elf/rtld.c index eb7b3bec2a..9f18e23b91 100644 --- a/elf/rtld.c +++ b/elf/rtld.c @@ -79,7 +79,7 @@ RTLD_START #error "sysdeps/MACHINE/dl-machine.h fails to define RTLD_START" #endif -ElfW(Addr) +static ElfW(Addr) _dl_start (void *arg) { struct link_map bootstrap_map; @@ -126,6 +126,10 @@ _dl_start (void *arg) _dl_rtld_map.l_info[DT_STRTAB]->d_un.d_ptr + _dl_rtld_map.l_info[DT_RPATH]->d_un.d_val); +#ifdef ELF_ADJUST_ARG + ELF_ADJUST_ARG(arg); +#endif + /* 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 @@ -147,7 +151,7 @@ dl_main (const ElfW(Phdr) *phdr, ElfW(Addr) *user_entry) { const ElfW(Phdr) *ph; - struct link_map *l; + struct link_map *main_map; int lazy; enum { normal, list, verify, trace } mode; struct link_map **preloads; @@ -235,7 +239,7 @@ of this helper program; chances are you did not intend to run this program.\n", { void doit (void) { - l = _dl_map_object (NULL, _dl_argv[0], lt_library, 0); + main_map = _dl_map_object (NULL, _dl_argv[0], lt_library, 0); } char *err_str = NULL; const char *obj_name __attribute__ ((unused)); @@ -248,37 +252,23 @@ of this helper program; chances are you did not intend to run this program.\n", } } else - l = _dl_map_object (NULL, _dl_argv[0], lt_library, 0); + main_map = _dl_map_object (NULL, _dl_argv[0], lt_library, 0); - phdr = l->l_phdr; - phent = l->l_phnum; - l->l_name = (char *) ""; - *user_entry = l->l_entry; + phdr = main_map->l_phdr; + phent = main_map->l_phnum; + main_map->l_name = (char *) ""; + *user_entry = main_map->l_entry; } else { /* Create a link_map for the executable itself. This will be what dlopen on "" returns. */ - l = _dl_new_object ((char *) "", "", lt_executable); - if (l == NULL) + main_map = _dl_new_object ((char *) "", "", lt_executable); + if (main_map == NULL) _dl_sysdep_fatal ("cannot allocate memory for link map", NULL); - l->l_phdr = phdr; - l->l_phnum = phent; - l->l_entry = *user_entry; - } - - if (l != _dl_loaded) - { - /* GDB assumes that the first element on the chain is the - link_map for the executable itself, and always skips it. - Make sure the first one is indeed that one. */ - l->l_prev->l_next = l->l_next; - if (l->l_next) - l->l_next->l_prev = l->l_prev; - l->l_prev = NULL; - l->l_next = _dl_loaded; - _dl_loaded->l_prev = l; - _dl_loaded = l; + main_map->l_phdr = phdr; + main_map->l_phnum = phent; + main_map->l_entry = *user_entry; } /* Scan the program header table for the dynamic section. */ @@ -288,7 +278,7 @@ of this helper program; chances are you did not intend to run this program.\n", case PT_DYNAMIC: /* This tells us where to find the dynamic section, which tells us everything we need to do. */ - l->l_ld = (void *) l->l_addr + ph->p_vaddr; + 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 @@ -297,7 +287,7 @@ of this helper program; chances are you did not intend to run this program.\n", 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 *) l->l_addr + ph->p_vaddr; + _dl_rtld_libname.name = (const char *) main_map->l_addr + ph->p_vaddr; _dl_rtld_libname.next = NULL; _dl_rtld_map.l_libname = &_dl_rtld_libname; has_interp = 1; @@ -317,25 +307,24 @@ of this helper program; chances are you did not intend to run this program.\n", if (mode == verify) /* We were called just to verify that this is a dynamic executable using us as the program interpreter. */ - _exit (l->l_ld == NULL ? 1 : has_interp ? 0 : 2); + _exit (main_map->l_ld == NULL ? 1 : has_interp ? 0 : 2); /* Extract the contents of the dynamic section for easy access. */ - elf_get_dynamic_info (l->l_ld, l->l_info); - if (l->l_info[DT_HASH]) + elf_get_dynamic_info (main_map->l_ld, main_map->l_info); + if (main_map->l_info[DT_HASH]) /* Set up our cache of pointers into the hash table. */ - _dl_setup_hash (l); + _dl_setup_hash (main_map); /* Put the link_map for ourselves on the chain so it can be found by - name. */ + name. Note that at this point the global chain of link maps contains + exactly one element, which is pointed to by main_map. */ if (! _dl_rtld_map.l_name) /* If not invoked directly, the dynamic linker shared object file was found by the PT_INTERP name. */ _dl_rtld_map.l_name = (char *) _dl_rtld_map.l_libname->name; _dl_rtld_map.l_type = lt_library; - while (l->l_next) - l = l->l_next; - l->l_next = &_dl_rtld_map; - _dl_rtld_map.l_prev = l; + main_map->l_next = &_dl_rtld_map; + _dl_rtld_map.l_prev = main_map; /* We have two ways to specify objects to preload: via environment variable and via the file /etc/ld.so.preload. The later can also @@ -445,7 +434,7 @@ of this helper program; chances are you did not intend to run this program.\n", /* 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. */ - _dl_map_object_deps (l, preloads, npreloads, mode == trace); + _dl_map_object_deps (main_map, preloads, npreloads, mode == trace); #ifndef MAP_ANON /* We are done mapping things, so close the zero-fill descriptor. */ @@ -465,11 +454,11 @@ of this helper program; chances are you did not intend to run this program.\n", chain in symbol search order because gdb uses the chain's order as its symbol search order. */ unsigned int i = 1; - while (l->l_searchlist[i] != &_dl_rtld_map) + while (main_map->l_searchlist[i] != &_dl_rtld_map) ++i; - _dl_rtld_map.l_prev = l->l_searchlist[i - 1]; - _dl_rtld_map.l_next = (i + 1 < l->l_nsearchlist ? - l->l_searchlist[i + 1] : NULL); + _dl_rtld_map.l_prev = main_map->l_searchlist[i - 1]; + _dl_rtld_map.l_next = (i + 1 < main_map->l_nsearchlist ? + main_map->l_searchlist[i + 1] : NULL); assert (_dl_rtld_map.l_prev->l_next == _dl_rtld_map.l_next); _dl_rtld_map.l_prev->l_next = &_dl_rtld_map; if (_dl_rtld_map.l_next) @@ -484,7 +473,7 @@ of this helper program; chances are you did not intend to run this program.\n", { void doit (void) { - if (_dl_check_all_versions (l, 1) && mode == normal) + if (_dl_check_all_versions (main_map, 1) && mode == normal) /* We cannot start the application. Abort now. */ _exit (1); } @@ -504,22 +493,26 @@ of this helper program; chances are you did not intend to run this program.\n", if (! _dl_loaded->l_info[DT_NEEDED]) _dl_sysdep_message ("\t", "statically linked\n", NULL); else - for (l = _dl_loaded->l_next; l; l = l->l_next) - if (l->l_opencount == 0) - /* The library was not found. */ - _dl_sysdep_message ("\t", l->l_libname->name, " => not found\n", - NULL); - else - { - char buf[20], *bp; - buf[sizeof buf - 1] = '\0'; - bp = _itoa (l->l_addr, &buf[sizeof buf - 1], 16, 0); - while ((size_t) (&buf[sizeof buf - 1] - bp) - < sizeof l->l_addr * 2) - *--bp = '0'; - _dl_sysdep_message ("\t", l->l_libname->name, " => ", l->l_name, - " (0x", bp, ")\n", NULL); - } + { + struct link_map *l; + + for (l = _dl_loaded->l_next; l; l = l->l_next) + if (l->l_opencount == 0) + /* The library was not found. */ + _dl_sysdep_message ("\t", l->l_libname->name, " => not found\n", + NULL); + else + { + char buf[20], *bp; + buf[sizeof buf - 1] = '\0'; + bp = _itoa (l->l_addr, &buf[sizeof buf - 1], 16, 0); + while ((size_t) (&buf[sizeof buf - 1] - bp) + < sizeof l->l_addr * 2) + *--bp = '0'; + _dl_sysdep_message ("\t", l->l_libname->name, " => ", + l->l_name, " (0x", bp, ")\n", NULL); + } + } if (mode != trace) for (i = 1; i < _dl_argc; ++i) @@ -544,6 +537,7 @@ of this helper program; chances are you did not intend to run this program.\n", else if (lazy >= 0) { /* We have to do symbol dependency testing. */ + struct link_map *l; void doit (void) { _dl_relocate_object (l, _dl_object_relocation_scope (l), lazy); @@ -576,6 +570,7 @@ of this helper program; chances are you did not intend to run this program.\n", the dynamic linker out of order because it has no copy relocs (we know that because it is self-contained). */ + struct link_map *l; l = _dl_loaded; while (l->l_next) l = l->l_next; @@ -605,6 +600,7 @@ of this helper program; chances are you did not intend to run this program.\n", { /* Initialize _r_debug. */ struct r_debug *r = _dl_debug_initialize (_dl_rtld_map.l_addr); + struct link_map *l; l = _dl_loaded; |