diff options
Diffstat (limited to 'drivers/net/wireless/ath/carl9170/rx.c')
| -rw-r--r-- | drivers/net/wireless/ath/carl9170/rx.c | 42 |
1 files changed, 41 insertions, 1 deletions
diff --git a/drivers/net/wireless/ath/carl9170/rx.c b/drivers/net/wireless/ath/carl9170/rx.c index 256dd42bb4ab..939a0e96ed1f 100644 --- a/drivers/net/wireless/ath/carl9170/rx.c +++ b/drivers/net/wireless/ath/carl9170/rx.c @@ -576,6 +576,41 @@ static void carl9170_ps_beacon(struct ar9170 *ar, void *data, unsigned int len) } } +static bool carl9170_ampdu_check(struct ar9170 *ar, u8 *buf, u8 ms) +{ + __le16 fc; + + if ((ms & AR9170_RX_STATUS_MPDU) == AR9170_RX_STATUS_MPDU_SINGLE) { + /* + * This frame is not part of an aMPDU. + * Therefore it is not subjected to any + * of the following content restrictions. + */ + return true; + } + + /* + * "802.11n - 7.4a.3 A-MPDU contents" describes in which contexts + * certain frame types can be part of an aMPDU. + * + * In order to keep the processing cost down, I opted for a + * stateless filter solely based on the frame control field. + */ + + fc = ((struct ieee80211_hdr *)buf)->frame_control; + if (ieee80211_is_data_qos(fc) && ieee80211_is_data_present(fc)) + return true; + + if (ieee80211_is_ack(fc) || ieee80211_is_back(fc) || + ieee80211_is_back_req(fc)) + return true; + + if (ieee80211_is_action(fc)) + return true; + + return false; +} + /* * If the frame alignment is right (or the kernel has * CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS), and there @@ -594,6 +629,7 @@ static void carl9170_handle_mpdu(struct ar9170 *ar, u8 *buf, int len) struct ieee80211_rx_status status; struct sk_buff *skb; int mpdu_len; + u8 mac_status; if (!IS_STARTED(ar)) return; @@ -604,7 +640,8 @@ static void carl9170_handle_mpdu(struct ar9170 *ar, u8 *buf, int len) mpdu_len = len - sizeof(*mac); mac = (void *)(buf + mpdu_len); - switch (mac->status & AR9170_RX_STATUS_MPDU) { + mac_status = mac->status; + switch (mac_status & AR9170_RX_STATUS_MPDU) { case AR9170_RX_STATUS_MPDU_FIRST: /* Aggregated MPDUs start with an PLCP header */ if (likely(mpdu_len >= sizeof(struct ar9170_rx_head))) { @@ -693,6 +730,9 @@ static void carl9170_handle_mpdu(struct ar9170 *ar, u8 *buf, int len) if (unlikely(carl9170_rx_mac_status(ar, head, mac, &status))) goto drop; + if (!carl9170_ampdu_check(ar, buf, mac_status)) + goto drop; + if (phy) carl9170_rx_phy_status(ar, phy, &status); |