This is a note to let you know that I've just added the patch titled
mac80211: use constant time comparison with keys
to the 3.18-stable tree which can be found at: http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git%3Ba=su...
The filename of the patch is: mac80211-use-constant-time-comparison-with-keys.patch and it can be found in the queue-3.18 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree, please let stable@vger.kernel.org know about it.
From 2bdd713b92a9cade239d3c7d15205a09f556624d Mon Sep 17 00:00:00 2001
From: "Jason A. Donenfeld" Jason@zx2c4.com Date: Tue, 17 Oct 2017 20:32:07 +0200 Subject: mac80211: use constant time comparison with keys
From: Jason A. Donenfeld Jason@zx2c4.com
commit 2bdd713b92a9cade239d3c7d15205a09f556624d upstream.
Otherwise we risk leaking information via timing side channel.
Fixes: fdf7cb4185b6 ("mac80211: accept key reinstall without changing anything") Signed-off-by: Jason A. Donenfeld Jason@zx2c4.com Signed-off-by: Johannes Berg johannes.berg@intel.com Cc: Ben Hutchings ben.hutchings@codethink.co.uk Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org
--- net/mac80211/key.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-)
--- a/net/mac80211/key.c +++ b/net/mac80211/key.c @@ -19,6 +19,7 @@ #include <linux/slab.h> #include <linux/export.h> #include <net/mac80211.h> +#include <crypto/algapi.h> #include <asm/unaligned.h> #include "ieee80211_i.h" #include "driver-ops.h" @@ -501,7 +502,7 @@ int ieee80211_key_link(struct ieee80211_ * new version of the key to avoid nonce reuse or replay issues. */ if (old_key && key->conf.keylen == old_key->conf.keylen && - !memcmp(key->conf.key, old_key->conf.key, key->conf.keylen)) { + !crypto_memneq(key->conf.key, old_key->conf.key, key->conf.keylen)) { ieee80211_key_free_unused(key); ret = 0; goto out;
Patches currently in stable-queue which might be from Jason@zx2c4.com are
queue-3.18/mac80211-use-constant-time-comparison-with-keys.patch