releases/4.9.30/stackprotector-increase-the-per-task-stack-canary-s-random-range-from-32-bits-to-64-bits-on-64-bit-platforms.patch

   1 From 5ea30e4e58040cfd6434c2f33dc3ea76e2c15b05 Mon Sep 17 00:00:00 2001
   2 From: Daniel Micay <danielmicay@gmail.com>
   3 Date: Thu, 4 May 2017 09:32:09 -0400
   4 Subject: stackprotector: Increase the per-task stack canary's random range from 32 bits to 64 bits on 64-bit platforms
   5
   6 From: Daniel Micay <danielmicay@gmail.com>
   7
   8 commit 5ea30e4e58040cfd6434c2f33dc3ea76e2c15b05 upstream.
   9
  10 The stack canary is an 'unsigned long' and should be fully initialized to
  11 random data rather than only 32 bits of random data.
  12
  13 Signed-off-by: Daniel Micay <danielmicay@gmail.com>
  14 Acked-by: Arjan van de Ven <arjan@linux.intel.com>
  15 Acked-by: Rik van Riel <riel@redhat.com>
  16 Acked-by: Kees Cook <keescook@chromium.org>
  17 Cc: Arjan van Ven <arjan@linux.intel.com>
  18 Cc: Linus Torvalds <torvalds@linux-foundation.org>
  19 Cc: Peter Zijlstra <peterz@infradead.org>
  20 Cc: Thomas Gleixner <tglx@linutronix.de>
  21 Cc: kernel-hardening@lists.openwall.com
  22 Link: http://lkml.kernel.org/r/20170504133209.3053-1-danielmicay@gmail.com
  23 Signed-off-by: Ingo Molnar <mingo@kernel.org>
  24 Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
  25
  26 ---
  27  kernel/fork.c |    2 +-
  28  1 file changed, 1 insertion(+), 1 deletion(-)
  29
  30 --- a/kernel/fork.c
  31 +++ b/kernel/fork.c
  32 @@ -521,7 +521,7 @@ static struct task_struct *dup_task_stru
  33         set_task_stack_end_magic(tsk);
  34
  35  #ifdef CONFIG_CC_STACKPROTECTOR
  36 -       tsk->stack_canary = get_random_int();
  37 +       tsk->stack_canary = get_random_long();
  38  #endif
  39
  40         /*