patches/kernel/0270-fs-prevent-speculative-execution.patch

   1 From 0000000000000000000000000000000000000000 Mon Sep 17 00:00:00 2001
   2 From: Elena Reshetova <elena.reshetova@intel.com>
   3 Date: Mon, 4 Sep 2017 13:11:54 +0300
   4 Subject: [PATCH] fs: prevent speculative execution
   5 MIME-Version: 1.0
   6 Content-Type: text/plain; charset=UTF-8
   7 Content-Transfer-Encoding: 8bit
   8
   9 CVE-2017-5753
  10 CVE-2017-5715
  11
  12 Real commit text tbd
  13
  14 Signed-off-by: Elena Reshetova <elena.reshetova@intel.com>
  15 Signed-off-by: Tim Chen <tim.c.chen@linux.intel.com>
  16 Signed-off-by: Andy Whitcroft <apw@canonical.com>
  17 Signed-off-by: Kleber Sacilotto de Souza <kleber.souza@canonical.com>
  18 (cherry picked from commit 1ca9e14b253a501f055c3ea29d992c028473676e)
  19 Signed-off-by: Fabian Grünbichler <f.gruenbichler@proxmox.com>
  20 ---
  21  include/linux/fdtable.h | 4 +++-
  22  1 file changed, 3 insertions(+), 1 deletion(-)
  23
  24 diff --git a/include/linux/fdtable.h b/include/linux/fdtable.h
  25 index 6e84b2cae6ad..09b124542bb8 100644
  26 --- a/include/linux/fdtable.h
  27 +++ b/include/linux/fdtable.h
  28 @@ -81,8 +81,10 @@ static inline struct file *__fcheck_files(struct files_struct *files, unsigned i
  29  {
  30         struct fdtable *fdt = rcu_dereference_raw(files->fdt);
  31
  32 -       if (fd < fdt->max_fds)
  33 +       if (fd < fdt->max_fds) {
  34 +               gmb();
  35                 return rcu_dereference_raw(fdt->fd[fd]);
  36 +       }
  37         return NULL;
  38  }
  39
  40 --
  41 2.14.2
  42