Reply-To: kernel-hardening@lists.openwall.com Sender: Vasiliy Kulikov Date: Sun, 26 Jul 2015 16:45:19 +0300 From: Vasily Kulikov Message-ID: <20150726134519.GA1111@cachalot> References: <20150726134324.GA1068@cachalot> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20150726134324.GA1068@cachalot> Subject: [kernel-hardening] [PATCH 2/3] use POISON_POINTER_DELTA for poison pointers To: linux-kernel@vger.kernel.org Cc: Randy Dunlap , Andrew Morton , kernel-hardening@lists.openwall.com, Thomas Gleixner , "Kirill A. Shutemov" List-ID: TIMER_ENTRY_STATIC and TAIL_MAPPING are defined as poison pointers which should point to nowhere. Redefine them using POISON_POINTER_DELTA arithmetics to make sure they really point to non-mappable area declared by the target architecture. Signed-off-by: Vasily Kulikov --- include/linux/poison.h | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/include/linux/poison.h b/include/linux/poison.h index ee697b9..a721bcd 100644 --- a/include/linux/poison.h +++ b/include/linux/poison.h @@ -27,14 +27,14 @@ * Magic number "tsta" to indicate a static timer initializer * for the object debugging code. */ -#define TIMER_ENTRY_STATIC ((void *) 0x74737461) +#define TIMER_ENTRY_STATIC ((void *) 0x300 + POISON_POINTER_DELTA) /********** mm/debug-pagealloc.c **********/ #define PAGE_POISON 0xaa /********** mm/page_alloc.c ************/ -#define TAIL_MAPPING ((void *) 0x01014A11 + POISON_POINTER_DELTA) +#define TAIL_MAPPING ((void *) 0x400 + POISON_POINTER_DELTA) /********** mm/slab.c **********/ /* -- 2.1.0