From e5d6eb8305a4c116fc94ce28b8136c538c92442f Mon Sep 17 00:00:00 2001 From: "Luis R. Rodriguez" Date: Mon, 9 Nov 2009 16:03:22 -0500 Subject: [PATCH] mac80211: fix max HT rate processing on mac80211 The max MCS index is 76, fix the higher check to allow through frames received at MCS 76. This is a non-issue for current drivers as MCS 76 is only possible with a device supporting 4 spatial streams. While at it change the WARN_ON() on invalid HT rates to a WARN() to provide more useful information. This will help debug issues when the driver is passing up a bogus HT rate value. The rate must map to a valid MCS index which can be any of the values in the set [0 - 76] (inclusive). Signed-off-by: Luis R. Rodriguez Signed-off-by: John W. Linville --- net/mac80211/rx.c | 18 +++++++++++++++--- 1 file changed, 15 insertions(+), 3 deletions(-) diff --git a/net/mac80211/rx.c b/net/mac80211/rx.c index 76478362a53..006cf89df70 100644 --- a/net/mac80211/rx.c +++ b/net/mac80211/rx.c @@ -2441,9 +2441,21 @@ void ieee80211_rx(struct ieee80211_hw *hw, struct sk_buff *skb) goto drop; if (status->flag & RX_FLAG_HT) { - /* rate_idx is MCS index */ - if (WARN_ON(status->rate_idx < 0 || - status->rate_idx >= 76)) + /* + * rate_idx is MCS index, which can be [0-76] as documented on: + * + * http://wireless.kernel.org/en/developers/Documentation/ieee80211/802.11n + * + * Anything else would be some sort of driver or hardware error. + * The driver should catch hardware errors. + */ + if (WARN((status->rate_idx < 0 || + status->rate_idx > 76), + "Rate marked as an HT rate but passed " + "status->rate_idx is not " + "an MCS index [0-76]: %d (0x%02x)\n", + status->rate_idx, + status->rate_idx)) goto drop; /* HT rates are not in the table - use the highest legacy rate * for now since other parts of mac80211 may not yet be fully