linux-kernel - [ 4/7] ath9k_htc: Restore skb headroom when returning skb to mac80211

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-Id: <20130905202758.127114460@linuxfoundation.org>
Date:	Thu,  5 Sep 2013 13:28:37 -0700
From:	Greg Kroah-Hartman <gregkh@...uxfoundation.org>
To:	linux-kernel@...r.kernel.org
Cc:	Greg Kroah-Hartman <gregkh@...uxfoundation.org>,
	stable@...r.kernel.org, Marc Kleine-Budde <mkl@...ckshift.org>,
	Helmut Schaa <helmut.schaa@...glemail.com>,
	"John W. Linville" <linville@...driver.com>
Subject: [ 4/7] ath9k_htc: Restore skb headroom when returning skb to mac80211

3.0-stable review patch.  If anyone has any objections, please let me know.

------------------

From: Helmut Schaa <helmut.schaa@...glemail.com>

commit d2e9fc141e2aa21f4b35ee27072d84e9aa6e2ba0 upstream.

ath9k_htc adds padding between the 802.11 header and the payload during
TX by moving the header. When handing the frame back to mac80211 for TX
status handling the header is not moved back into its original position.
This can result in a too small skb headroom when entering ath9k_htc
again (due to a soft retransmission for example) causing an
skb_under_panic oops.

Fix this by moving the 802.11 header back into its original position
before returning the frame to mac80211 as other drivers like rt2x00
or ath5k do.

Reported-by: Marc Kleine-Budde <mkl@...ckshift.org>
Signed-off-by: Helmut Schaa <helmut.schaa@...glemail.com>
Tested-by: Marc Kleine-Budde <mkl@...ckshift.org>
Signed-off-by: Marc Kleine-Budde <mkl@...ckshift.org>
Signed-off-by: John W. Linville <linville@...driver.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@...uxfoundation.org>

---
 drivers/net/wireless/ath/ath9k/htc_drv_txrx.c |   10 ++++++++++
 1 file changed, 10 insertions(+)

--- a/drivers/net/wireless/ath/ath9k/htc_drv_txrx.c
+++ b/drivers/net/wireless/ath/ath9k/htc_drv_txrx.c
@@ -448,6 +448,7 @@ static void ath9k_htc_tx_process(struct
 	struct ieee80211_conf *cur_conf = &priv->hw->conf;
 	bool txok;
 	int slot;
+	int hdrlen, padsize;

 	slot = strip_drv_header(priv, skb);
 	if (slot < 0) {
@@ -504,6 +505,15 @@ send_mac80211:

 	ath9k_htc_tx_clear_slot(priv, slot);

+	/* Remove padding before handing frame back to mac80211 */
+	hdrlen = ieee80211_get_hdrlen_from_skb(skb);
+
+	padsize = hdrlen & 3;
+	if (padsize && skb->len > hdrlen + padsize) {
+		memmove(skb->data + padsize, skb->data, hdrlen);
+		skb_pull(skb, padsize);
+	}
+
 	/* Send status to mac80211 */
 	ieee80211_tx_status(priv->hw, skb);
 }

--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/