glibc/SOURCES/glibc-rh2233338-1.patch

38 lines
1.3 KiB
Diff

commit 7b5bfe77836442b9aeb75cc520f0d1eb7f82be67
Author: Florian Weimer <fweimer@redhat.com>
Date: Mon May 18 15:21:04 2020 +0200
elf: Assert that objects are relocated before their constructors run
If we try to run constructors before relocation, this is always
a dynamic linker bug. An assert is easier to notice than a call
via an invalid function pointer (which may not even produce a valid
call stack).
Reviewed-by: Carlos O'Donell <carlos@redhat.com>
diff --git a/elf/dl-init.c b/elf/dl-init.c
index 45405cd0563845b4..99ce531d7b326f5f 100644
--- a/elf/dl-init.c
+++ b/elf/dl-init.c
@@ -16,6 +16,7 @@
License along with the GNU C Library; if not, see
<http://www.gnu.org/licenses/>. */
+#include <assert.h>
#include <stddef.h>
#include <ldsodefs.h>
@@ -27,6 +28,11 @@ typedef void (*init_t) (int, char **, char **);
static void
call_init (struct link_map *l, int argc, char **argv, char **env)
{
+ /* If the object has not been relocated, this is a bug. The
+ function pointers are invalid in this case. (Executables do not
+ need relocation, and neither do proxy objects.) */
+ assert (l->l_real->l_relocated || l->l_real->l_type == lt_executable);
+
if (l->l_init_called)
/* This object is all done. */
return;