Return-path: Received: from vs166246.vserver.de ([62.75.166.246]:45294 "EHLO vs166246.vserver.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753932AbXL2QZy (ORCPT ); Sat, 29 Dec 2007 11:25:54 -0500 From: Michael Buesch To: Daniel Drake Subject: Re: Strange mac80211 oops Date: Sat, 29 Dec 2007 17:24:23 +0100 Cc: Johannes Berg , linux-wireless@vger.kernel.org, John Linville References: <200712242237.28913.mb@bu3sch.de> <47764C5A.7060109@gentoo.org> <1198936128.4172.41.camel@johannes.berg> In-Reply-To: <1198936128.4172.41.camel@johannes.berg> MIME-Version: 1.0 Message-Id: <200712291724.23726.mb@bu3sch.de> (sfid-20071229_162558_444791_97F21B69) Content-Type: text/plain; charset="utf-8" Sender: linux-wireless-owner@vger.kernel.org List-ID: This patch fixes RX packet alignment issues in the zd1211rw driver. This is based on a patch by Johannes Berg. Signed-off-by: Michael Buesch Index: wireless-2.6/drivers/net/wireless/zd1211rw/zd_mac.c =================================================================== --- wireless-2.6.orig/drivers/net/wireless/zd1211rw/zd_mac.c 2007-12-29 17:14:41.000000000 +0100 +++ wireless-2.6/drivers/net/wireless/zd1211rw/zd_mac.c 2007-12-29 17:15:00.000000000 +0100 @@ -623,6 +623,8 @@ int zd_mac_rx(struct ieee80211_hw *hw, c const struct rx_status *status; struct sk_buff *skb; int bad_frame = 0; + u16 fc; + bool is_qos, is_4addr, need_padding; if (length < ZD_PLCP_HEADER_SIZE + 10 /* IEEE80211_1ADDR_LEN */ + FCS_LEN + sizeof(struct rx_status)) @@ -674,9 +676,22 @@ int zd_mac_rx(struct ieee80211_hw *hw, c && !mac->pass_ctrl) return 0; - skb = dev_alloc_skb(length); + fc = le16_to_cpu(*((__le16 *) buffer)); + + is_qos = ((fc & IEEE80211_FCTL_FTYPE) == IEEE80211_FTYPE_DATA) && + ((fc & IEEE80211_FCTL_STYPE) == IEEE80211_STYPE_QOS_DATA); + is_4addr = (fc & (IEEE80211_FCTL_TODS | IEEE80211_FCTL_FROMDS)) == + (IEEE80211_FCTL_TODS | IEEE80211_FCTL_FROMDS); + need_padding = is_qos ^ is_4addr; + + skb = dev_alloc_skb(length + (need_padding ? 2 : 0)); if (skb == NULL) return -ENOMEM; + if (need_padding) { + /* Make sure the the payload data is 4 byte aligned. */ + skb_reserve(skb, 2); + } + memcpy(skb_put(skb, length), buffer, length); ieee80211_rx_irqsafe(hw, skb, &stats);