diff options
Diffstat (limited to 'elf/dl-sym.c')
-rw-r--r-- | elf/dl-sym.c | 85 |
1 files changed, 81 insertions, 4 deletions
diff --git a/elf/dl-sym.c b/elf/dl-sym.c index d2b0ec0dab..1c66310d7c 100644 --- a/elf/dl-sym.c +++ b/elf/dl-sym.c @@ -17,6 +17,7 @@ Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA. */ +#include <assert.h> #include <stddef.h> #include <setjmp.h> #include <libintl.h> @@ -58,6 +59,30 @@ _dl_tls_symaddr (struct link_map *map, const ElfW(Sym) *ref) #endif +struct call_dl_lookup_args +{ + /* Arguments to do_dlsym. */ + struct link_map *map; + const char *name; + struct r_scope_elem **scope; + struct r_found_version *vers; + int flags; + + /* Return values of do_dlsym. */ + lookup_t loadbase; + const ElfW(Sym) **refp; +}; + +static void +call_dl_lookup (void *ptr) +{ + struct call_dl_lookup_args *args = (struct call_dl_lookup_args *) ptr; + args->map = GLRO(dl_lookup_symbol_x) (args->name, args->map, args->refp, + args->scope, args->vers, 0, + args->flags, NULL); +} + + static void * internal_function do_sym (void *handle, const char *name, void *who, @@ -84,10 +109,62 @@ do_sym (void *handle, const char *name, void *who, } if (handle == RTLD_DEFAULT) - /* Search the global scope. */ - result = GLRO(dl_lookup_symbol_x) (name, match, &ref, match->l_scope, - vers, 0, flags|DL_LOOKUP_ADD_DEPENDENCY, - NULL); + { + /* Search the global scope. We have the simple case where + we look up in the scope of an object which was part of + the initial binary. And then the more complex part + where the object is dynamically loaded and the scope + array can change. */ + if (match->l_type != lt_loaded) + result = GLRO(dl_lookup_symbol_x) (name, match, &ref, + match->l_scoperec->scope, vers, 0, + flags | DL_LOOKUP_ADD_DEPENDENCY, + NULL); + else + { + __rtld_mrlock_lock (match->l_scoperec_lock); + struct r_scoperec *scoperec = match->l_scoperec; + atomic_increment (&scoperec->nusers); + __rtld_mrlock_unlock (match->l_scoperec_lock); + + struct call_dl_lookup_args args; + args.name = name; + args.map = match; + args.scope = scoperec->scope; + args.vers = vers; + args.flags = flags | DL_LOOKUP_ADD_DEPENDENCY; + args.refp = &ref; + + const char *objname; + const char *errstring = NULL; + bool malloced; + int err = GLRO(dl_catch_error) (&objname, &errstring, &malloced, + call_dl_lookup, &args); + + if (atomic_decrement_val (&scoperec->nusers) == 0 + && __builtin_expect (scoperec->remove_after_use, 0)) + { + if (scoperec->notify) + __rtld_notify (scoperec->nusers); + else + free (scoperec); + } + + if (__builtin_expect (errstring != NULL, 0)) + { + /* The lookup was unsuccessful. Rethrow the error. */ + char *errstring_dup = strdupa (errstring); + char *objname_dup = strdupa (objname); + if (malloced) + free ((char *) errstring); + + GLRO(dl_signal_error) (err, objname_dup, NULL, errstring_dup); + /* NOTREACHED */ + } + + result = args.map; + } + } else if (handle == RTLD_NEXT) { if (__builtin_expect (match == GL(dl_ns)[LM_ID_BASE]._ns_loaded, 0)) |