4.13-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" @@ -635,7 +636,7 @@ 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;