package/kernel/mac80211/patches/328-mac80211-use-constant-time-comparison-with-keys.patch

   1 From 2bdd713b92a9cade239d3c7d15205a09f556624d Mon Sep 17 00:00:00 2001
   2 From: "Jason A. Donenfeld" <Jason@zx2c4.com>
   3 Date: Tue, 17 Oct 2017 20:32:07 +0200
   4 Subject: [PATCH] mac80211: use constant time comparison with keys
   5
   6 Otherwise we risk leaking information via timing side channel.
   7
   8 Fixes: fdf7cb4185b6 ("mac80211: accept key reinstall without changing anything")
   9 Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com>
  10 Signed-off-by: Johannes Berg <johannes.berg@intel.com>
  11 ---
  12  net/mac80211/key.c | 3 ++-
  13  1 file changed, 2 insertions(+), 1 deletion(-)
  14
  15 --- a/net/mac80211/key.c
  16 +++ b/net/mac80211/key.c
  17 @@ -19,6 +19,7 @@
  18  #include <linux/slab.h>
  19  #include <linux/export.h>
  20  #include <net/mac80211.h>
  21 +#include <crypto/algapi.h>
  22  #include <asm/unaligned.h>
  23  #include "ieee80211_i.h"
  24  #include "driver-ops.h"
  25 @@ -635,7 +636,7 @@ int ieee80211_key_link(struct ieee80211_
  26          * new version of the key to avoid nonce reuse or replay issues.
  27          */
  28         if (old_key && key->conf.keylen == old_key->conf.keylen &&
  29 -           !memcmp(key->conf.key, old_key->conf.key, key->conf.keylen)) {
  30 +           !crypto_memneq(key->conf.key, old_key->conf.key, key->conf.keylen)) {
  31                 ieee80211_key_free_unused(key);
  32                 ret = 0;
  33                 goto out;