[cfe-dev] Sanitizer and "downcast of address 0xXX...XXX with insufficient space for an object of type '_Rb_tree_node' "

[Jeffrey Walton]

Hi All,

What is this finding trying to tell me.

The iterator is a typedef for _Base_ptr, and the address of _M_header
is a pointer. _Link_type is typedef'd as a _Rb_tree_node<_Tp>*. So I
don't see a width problem.

*****
Testing ECDSA (InSiTo unit tests):
../usr/include/c++/4.2.1/bits/stl_tree.h:620:25: runtime error:
downcast of address 0x7fff5598fe88 with insufficient space for an
object of type '_Rb_tree_node' (aka '_Rb_tree_node<std::pair<const
Botan::OID, std::basic_string<char> > >')
0x7fff5598fe88: note: pointer points here
 00 00 00 00  00 00 00 00 00 00 00 00  10 a7 14 01 70 60 00 00  80 a7
14 01 70 60 00 00  c0 a5 14 01
              ^
*****
>From stl_tree.h:

  618    iterator
  619    end()
  620    { return iterator(static_cast<_Link_type>(&this->_M_impl._M_header)); }

*****
OS X 10.8.3

$ uname -a
Darwin riemann.home.pvt 12.4.0 Darwin Kernel Version 12.4.0: Wed May
1 17:57:12 PDT 2013; root:xnu-2050.24.15~1/RELEASE_X86_64 x86_64