In some cases it can be useful to change the MAC address of a virtual
interface to something that's completely different from the EEPROM
stored MAC address. In this case it is a bad idea to use the EEPROM MAC
address for calculating the BSSID mask, as that would make it too wide.
In one case a few devices have been observed to send ACKs for many
packets on the channel not directed at them, which results in a neat
Denial of Service attack on the channel.
Signed-off-by: Felix Fietkau <nbd@xxxxxxxxxxx>
---
drivers/net/wireless/ath/ath9k/ath9k.h | 7 +++----
drivers/net/wireless/ath/ath9k/main.c | 9 +++++++--
2 files changed, 10 insertions(+), 6 deletions(-)
diff --git a/drivers/net/wireless/ath/ath9k/ath9k.h b/drivers/net/wireless/ath/ath9k/ath9k.h
index 86d3572..1915f12 100644
--- a/drivers/net/wireless/ath/ath9k/ath9k.h
+++ b/drivers/net/wireless/ath/ath9k/ath9k.h
@@ -658,11 +658,10 @@ enum sc_op_flags {
struct ath_rate_table;
struct ath9k_vif_iter_data {
- const u8 *hw_macaddr; /* phy's hardware address, set
- * before starting iteration for
- * valid bssid mask.
- */
+ u8 hw_macaddr[ETH_ALEN]; /* address of the first vif */
u8 mask[ETH_ALEN]; /* bssid mask */
+ bool has_hw_macaddr;
+
int naps; /* number of AP vifs */
int nmeshes; /* number of mesh vifs */
int nstations; /* number of station vifs */
diff --git a/drivers/net/wireless/ath/ath9k/main.c b/drivers/net/wireless/ath/ath9k/main.c
index a383483..6963862 100644
--- a/drivers/net/wireless/ath/ath9k/main.c
+++ b/drivers/net/wireless/ath/ath9k/main.c
@@ -839,10 +839,14 @@ static void ath9k_vif_iter(void *data, u8 *mac, struct ieee80211_vif *vif)
struct ath9k_vif_iter_data *iter_data = data;
int i;
- if (iter_data->hw_macaddr)
+ if (iter_data->has_hw_macaddr) {
for (i = 0; i < ETH_ALEN; i++)
iter_data->mask[i] &=
~(iter_data->hw_macaddr[i] ^ mac[i]);
+ } else {
+ memcpy(iter_data->hw_macaddr, mac, ETH_ALEN);
+ iter_data->has_hw_macaddr = true;
+ }
switch (vif->type) {
case NL80211_IFTYPE_AP:
@@ -891,7 +895,6 @@ void ath9k_calculate_iter_data(struct ieee80211_hw *hw,
* together with the BSSID mask when matching addresses.
*/
memset(iter_data, 0, sizeof(*iter_data));
- iter_data->hw_macaddr = common->macaddr;
memset(&iter_data->mask, 0xff, ETH_ALEN);
if (vif)
@@ -901,6 +904,8 @@ void ath9k_calculate_iter_data(struct ieee80211_hw *hw,
ieee80211_iterate_active_interfaces_atomic(
sc->hw, IEEE80211_IFACE_ITER_RESUME_ALL,
ath9k_vif_iter, iter_data);
+
+ memcpy(common->macaddr, iter_data->hw_macaddr, ETH_ALEN);
}
/* Called with sc->mutex held. */
--
1.8.0.2
--
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