[PATCH] BZ #15754: CVE-2013-4788: PTR_MANGLE does not initialize to a random value for the pointer guard when compiling static executables

[Andreas Schwab]

"Carlos O'Donell" <carlos@redhat.com> writes:

> - Fix sysdeps/generic/stackguard-macros.h
>
> 	* sysdeps/generic/stackguard-macros.h: Define __pointer_chk_guard
> 	and POINTER_CHK_GUARD.
>
> diff --git a/sysdeps/generic/stackguard-macros.h b/sysdeps/generic/stackguard-macros.h
> index ababf65..77408c6 100644
> --- a/sysdeps/generic/stackguard-macros.h
> +++ b/sysdeps/generic/stackguard-macros.h
> @@ -2,3 +2,6 @@
>  
>  extern uintptr_t __stack_chk_guard;
>  #define STACK_CHK_GUARD __stack_chk_guard
> +
> +extern uintptr_t __pointer_chk_guard;
> +#define POINTER_CHK_GUARD __pointer_chk_guard

That won't work, __pointer_chk_guard is only available in ld.so, it is
called __pointer_chk_guard_local in libc.a.

Andreas.

-- 
Andreas Schwab, SUSE Labs, schwab@suse.de
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