This is a note to let you know that I've just added the patch titled
mac80211/wpa: use constant time memory comparison for MACs
to the 3.18-stable tree which can be found at:
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary
The filename of the patch is:
mac80211-wpa-use-constant-time-memory-comparison-for-macs.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@xxxxxxxxxxxxxxx> know about it.
>From 98c67d187db7808b1f3c95f2110dd4392d034182 Mon Sep 17 00:00:00 2001
From: "Jason A. Donenfeld" <Jason@xxxxxxxxx>
Date: Sat, 10 Jun 2017 04:59:12 +0200
Subject: mac80211/wpa: use constant time memory comparison for MACs
From: Jason A. Donenfeld <Jason@xxxxxxxxx>
commit 98c67d187db7808b1f3c95f2110dd4392d034182 upstream.
Otherwise, we enable all sorts of forgeries via timing attack.
Signed-off-by: Jason A. Donenfeld <Jason@xxxxxxxxx>
Cc: Johannes Berg <johannes@xxxxxxxxxxxxxxxx>
Cc: linux-wireless@xxxxxxxxxxxxxxx
Cc: stable@xxxxxxxxxxxxxxx
Signed-off-by: Johannes Berg <johannes.berg@xxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
net/mac80211/wpa.c | 5 +++--
1 file changed, 3 insertions(+), 2 deletions(-)
--- a/net/mac80211/wpa.c
+++ b/net/mac80211/wpa.c
@@ -16,6 +16,7 @@
#include <asm/unaligned.h>
#include <net/mac80211.h>
#include <crypto/aes.h>
+#include <crypto/algapi.h>
#include "ieee80211_i.h"
#include "michael.h"
@@ -150,7 +151,7 @@ ieee80211_rx_h_michael_mic_verify(struct
data_len = skb->len - hdrlen - MICHAEL_MIC_LEN;
key = &rx->key->conf.key[NL80211_TKIP_DATA_OFFSET_RX_MIC_KEY];
michael_mic(key, hdr, data, data_len, mic);
- if (memcmp(mic, data + data_len, MICHAEL_MIC_LEN) != 0)
+ if (crypto_memneq(mic, data + data_len, MICHAEL_MIC_LEN))
goto mic_fail;
/* remove Michael MIC from payload */
@@ -771,7 +772,7 @@ ieee80211_crypto_aes_cmac_decrypt(struct
bip_aad(skb, aad);
ieee80211_aes_cmac(key->u.aes_cmac.tfm, aad,
skb->data + 24, skb->len - 24, mic);
- if (memcmp(mic, mmie->mic, sizeof(mmie->mic)) != 0) {
+ if (crypto_memneq(mic, mmie->mic, sizeof(mmie->mic))) {
key->u.aes_cmac.icverrors++;
return RX_DROP_UNUSABLE;
}
Patches currently in stable-queue which might be from Jason@xxxxxxxxx are
queue-3.18/mac80211-wpa-use-constant-time-memory-comparison-for-macs.patch