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2.5-18.1

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This commit is contained in:
Jakub Jelinek
2007-07-12 18:26:36 +00:00
parent 7d58530341
commit 0ecb606cb6
6215 changed files with 494638 additions and 305010 deletions
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142
elf/dl-sym.c
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@@ -1,5 +1,5 @@
/* Look up a symbol in a shared object loaded by `dlopen'.
Copyright (C) 1999, 2000, 2001, 2002, 2004 Free Software Foundation, Inc.
Copyright (C) 1999-2002,2004,2006,2007 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
@@ -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>
@@ -24,6 +25,7 @@
#include <dlfcn.h>
#include <ldsodefs.h>
#include <dl-hash.h>
#include <sysdep-cancel.h>
#ifdef USE_TLS
# include <dl-tls.h>
#endif
@@ -58,6 +60,29 @@ _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_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->map->l_scope, args->vers, 0,
args->flags, NULL);
}
static void *
internal_function
do_sym (void *handle, const char *name, void *who,
@@ -75,19 +100,59 @@ do_sym (void *handle, const char *name, void *who,
for (Lmid_t ns = 0; ns < DL_NNS; ++ns)
for (struct link_map *l = GL(dl_ns)[ns]._ns_loaded; l != NULL;
l = l->l_next)
if (caller >= l->l_map_start && caller < l->l_map_end)
if (caller >= l->l_map_start && caller < l->l_map_end
&& (l->l_contiguous || _dl_addr_inside_object (l, caller)))
{
/* There must be exactly one DSO for the range of the virtual
memory. Otherwise something is really broken. */
match = l;
break;
}
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 (RTLD_SINGLE_THREAD_P)
result = GLRO(dl_lookup_symbol_x) (name, match, &ref,
match->l_scope, vers, 0,
flags | DL_LOOKUP_ADD_DEPENDENCY,
NULL);
else
{
struct call_dl_lookup_args args;
args.name = name;
args.map = match;
args.vers = vers;
args.flags = flags | DL_LOOKUP_ADD_DEPENDENCY;
args.refp = &ref;
THREAD_GSCOPE_SET_FLAG ();
const char *objname;
const char *errstring = NULL;
bool malloced;
int err = GLRO(dl_catch_error) (&objname, &errstring, &malloced,
call_dl_lookup, &args);
THREAD_GSCOPE_RESET_FLAG ();
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))
@@ -103,7 +168,7 @@ RTLD_NEXT used in code not dynamically loaded"));
while (l->l_loader != NULL)
l = l->l_loader;
result = GLRO(dl_lookup_symbol_x) (name, l, &ref, l->l_local_scope,
result = GLRO(dl_lookup_symbol_x) (name, match, &ref, l->l_local_scope,
vers, 0, 0, match);
}
else
@@ -116,14 +181,69 @@ RTLD_NEXT used in code not dynamically loaded"));
if (ref != NULL)
{
void *value;
#if defined USE_TLS && defined SHARED
if (ELFW(ST_TYPE) (ref->st_info) == STT_TLS)
/* The found symbol is a thread-local storage variable.
Return the address for to the current thread. */
return _dl_tls_symaddr (result, ref);
value = _dl_tls_symaddr (result, ref);
else
#endif
value = DL_SYMBOL_ADDRESS (result, ref);
#ifdef SHARED
/* Auditing checkpoint: we have a new binding. Provide the
auditing libraries the possibility to change the value and
tell us whether further auditing is wanted. */
if (__builtin_expect (GLRO(dl_naudit) > 0, 0))
{
const char *strtab = (const char *) D_PTR (result,
l_info[DT_STRTAB]);
/* Compute index of the symbol entry in the symbol table of
the DSO with the definition. */
unsigned int ndx = (ref - (ElfW(Sym) *) D_PTR (result,
l_info[DT_SYMTAB]));
if ((match->l_audit_any_plt | result->l_audit_any_plt) != 0)
{
unsigned int altvalue = 0;
struct audit_ifaces *afct = GLRO(dl_audit);
/* Synthesize a symbol record where the st_value field is
the result. */
ElfW(Sym) sym = *ref;
sym.st_value = (ElfW(Addr)) value;
for (unsigned int cnt = 0; cnt < GLRO(dl_naudit); ++cnt)
{
if (afct->symbind != NULL
&& ((match->l_audit[cnt].bindflags & LA_FLG_BINDFROM)
!= 0
|| ((result->l_audit[cnt].bindflags & LA_FLG_BINDTO)
!= 0)))
{
unsigned int flags = altvalue | LA_SYMB_DLSYM;
uintptr_t new_value
= afct->symbind (&sym, ndx,
&match->l_audit[cnt].cookie,
&result->l_audit[cnt].cookie,
&flags, strtab + ref->st_name);
if (new_value != (uintptr_t) sym.st_value)
{
altvalue = LA_SYMB_ALTVALUE;
sym.st_value = new_value;
}
}
afct = afct->next;
}
value = (void *) sym.st_value;
}
}
#endif
return DL_SYMBOL_ADDRESS (result, ref);
return value;
}
return NULL;