4.4-stable review patch. If anyone has any objections, please let me know.
------------------
From: Jason A. Donenfeld <Jason@xxxxxxxxx>
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@xxxxxxxxx>
Signed-off-by: Johannes Berg <johannes.berg@xxxxxxxxx>
Cc: Ben Hutchings <ben.hutchings@xxxxxxxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
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"
@@ -633,7 +634,7 @@ 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;