gcc/gcc41-dtor-relro.patch
Jakub Jelinek a1271c1402 4.1.2-12
2007-05-03 22:15:08 +00:00

90 lines
2.6 KiB
Diff

2007-05-03 Ulrich Drepper <drepper@redhat.com>
Jakub Jelinek <jakub@redhat.com>
* crtstuff.c (HIDDEN_DTOR_LIST_END): New macro.
(__do_global_dtors_aux): Use more paranoid loop to run
destructors if HIDDEN_DTOR_LIST_END.
(__DTOR_END__): Export as a hidden symbol when HIDDEN_DTOR_LIST_END.
--- gcc/crtstuff.c.jj 2007-01-24 22:24:21.000000000 +0100
+++ gcc/crtstuff.c 2007-05-03 10:40:29.000000000 +0200
@@ -106,6 +107,11 @@ call_ ## FUNC (void) \
# define EH_FRAME_SECTION_CONST
#endif
+#if !defined(DTOR_LIST_END) && defined(OBJECT_FORMAT_ELF) \
+ && defined(HAVE_GAS_HIDDEN) && !defined(FINI_ARRAY_SECTION_ASM_OP)
+# define HIDDEN_DTOR_LIST_END
+#endif
+
/* We do not want to add the weak attribute to the declarations of these
routines in unwind-dw2-fde.h because that will cause the definition of
these symbols to be weak as well.
@@ -265,10 +271,6 @@ extern void __cxa_finalize (void *) TARG
static void __attribute__((used))
__do_global_dtors_aux (void)
{
-#ifndef FINI_ARRAY_SECTION_ASM_OP
- static func_ptr *p = __DTOR_LIST__ + 1;
- func_ptr f;
-#endif /* !defined(FINI_ARRAY_SECTION_ASM_OP) */
static _Bool completed;
if (__builtin_expect (completed, 0))
@@ -282,12 +284,32 @@ __do_global_dtors_aux (void)
#ifdef FINI_ARRAY_SECTION_ASM_OP
/* If we are using .fini_array then destructors will be run via that
mechanism. */
+#elif defined(HIDDEN_DTOR_LIST_END)
+ {
+ /* Safer version that makes sure only .dtors function pointers are
+ called even if the static variable is maliciously changed. */
+ extern func_ptr __DTOR_END__[] __attribute__((visibility ("hidden")));
+ static size_t dtor_idx;
+ const size_t max_idx = __DTOR_END__ - __DTOR_LIST__ - 1;
+ func_ptr f;
+
+ while (dtor_idx < max_idx)
+ {
+ f = __DTOR_LIST__[++dtor_idx];
+ f ();
+ }
+ }
#else /* !defined (FINI_ARRAY_SECTION_ASM_OP) */
- while ((f = *p))
- {
- p++;
- f ();
- }
+ {
+ static func_ptr *p = __DTOR_LIST__ + 1;
+ func_ptr f;
+
+ while ((f = *p))
+ {
+ p++;
+ f ();
+ }
+ }
#endif /* !defined(FINI_ARRAY_SECTION_ASM_OP) */
#ifdef USE_EH_FRAME_REGISTRY
@@ -471,6 +493,17 @@ STATIC func_ptr __CTOR_END__[1]
#ifdef DTOR_LIST_END
DTOR_LIST_END;
+#elif defined(HIDDEN_DTOR_LIST_END)
+#ifdef DTORS_SECTION_ASM_OP
+asm (DTORS_SECTION_ASM_OP);
+#endif
+func_ptr __DTOR_END__[1]
+ __attribute__ ((unused,
+#ifndef DTORS_SECTION_ASM_OP
+ section(".dtors"),
+#endif
+ aligned(sizeof(func_ptr)), visibility ("hidden")))
+ = { (func_ptr) 0 };
#elif defined(DTORS_SECTION_ASM_OP)
asm (DTORS_SECTION_ASM_OP);
STATIC func_ptr __DTOR_END__[1]