diff options
| author | Johannes Berg <johannes@sipsolutions.net> | 2007-12-18 15:11:35 +0100 |
|---|---|---|
| committer | David S. Miller <davem@davemloft.net> | 2007-12-26 19:36:32 -0800 |
| commit | 81100eb80add328c4d2a377326f15aa0e7236398 (patch) | |
| tree | 03b8f14120b8c2aece64bc7f13d52cb4a190b091 | |
| parent | 0d17440688ad83de46e94e9fa11edb5a7fb3d180 (diff) | |
mac80211: warn when receiving frames with unaligned data
This patch makes mac80211 warn (once) when the driver passes up a
frame in which the payload data is not aligned on a four-byte
boundary, with a long comment for people who run into the condition
and need to know what to do.
Signed-off-by: Johannes Berg <johannes@sipsolutions.net>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
| -rw-r--r-- | net/mac80211/rx.c | 13 |
1 files changed, 13 insertions, 0 deletions
diff --git a/net/mac80211/rx.c b/net/mac80211/rx.c index 00f908d9275e..a7263fc476bd 100644 --- a/net/mac80211/rx.c +++ b/net/mac80211/rx.c @@ -1443,6 +1443,7 @@ void __ieee80211_rx(struct ieee80211_hw *hw, struct sk_buff *skb, struct ieee80211_sub_if_data *prev = NULL; struct sk_buff *skb_new; u8 *bssid; + int hdrlen; /* * key references and virtual interfaces are protected using RCU @@ -1472,6 +1473,18 @@ void __ieee80211_rx(struct ieee80211_hw *hw, struct sk_buff *skb, rx.fc = le16_to_cpu(hdr->frame_control); type = rx.fc & IEEE80211_FCTL_FTYPE; + /* + * Drivers are required to align the payload data to a four-byte + * boundary, so the last two bits of the address where it starts + * may not be set. The header is required to be directly before + * the payload data, padding like atheros hardware adds which is + * inbetween the 802.11 header and the payload is not supported, + * the driver is required to move the 802.11 header further back + * in that case. + */ + hdrlen = ieee80211_get_hdrlen(rx.fc); + WARN_ON_ONCE(((unsigned long)(skb->data + hdrlen)) & 3); + if (type == IEEE80211_FTYPE_DATA || type == IEEE80211_FTYPE_MGMT) local->dot11ReceivedFragmentCount++; |