doc: self-protection: Add information about STACKLEAK feature

Add information about STACKLEAK feature to the "Memory poisoning"
section of self-protection.rst.

Signed-off-by: Alexander Popov <alex.popov@linux.com>
Signed-off-by: Kees Cook <keescook@chromium.org>
This commit is contained in:
Alexander Popov 2018-08-17 01:17:02 +03:00 committed by Kees Cook
parent c8d126275a
commit ed535a2dae

View File

@ -302,11 +302,11 @@ sure structure holes are cleared.
Memory poisoning
----------------
When releasing memory, it is best to poison the contents (clear stack on
syscall return, wipe heap memory on a free), to avoid reuse attacks that
rely on the old contents of memory. This frustrates many uninitialized
variable attacks, stack content exposures, heap content exposures, and
use-after-free attacks.
When releasing memory, it is best to poison the contents, to avoid reuse
attacks that rely on the old contents of memory. E.g., clear stack on a
syscall return (``CONFIG_GCC_PLUGIN_STACKLEAK``), wipe heap memory on a
free. This frustrates many uninitialized variable attacks, stack content
exposures, heap content exposures, and use-after-free attacks.
Destination tracking
--------------------