From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Eric Dumazet , "David S. Miller" Subject: [PATCH 3.17 39/47] net: mvneta: fix race condition in mvneta_tx() Date: Sun, 14 Dec 2014 12:21:14 -0800 Message-Id: <20141214201820.044152013@linuxfoundation.org> In-Reply-To: <20141214201818.552715149@linuxfoundation.org> References: <20141214201818.552715149@linuxfoundation.org> MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Sender: linux-kernel-owner@vger.kernel.org List-ID: 3.17-stable review patch. If anyone has any objections, please let me know. ------------------ From: Eric Dumazet [ Upstream commit 5f478b41033606d325e420df693162e2524c2b94 ] mvneta_tx() dereferences skb to get skb->len too late, as hardware might have completed the transmit and TX completion could have freed the skb from another cpu. Fixes: 71f6d1b31fb1 ("net: mvneta: replace Tx timer with a real interrupt") Signed-off-by: Eric Dumazet Signed-off-by: David S. Miller Signed-off-by: Greg Kroah-Hartman --- drivers/net/ethernet/marvell/mvneta.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) --- a/drivers/net/ethernet/marvell/mvneta.c +++ b/drivers/net/ethernet/marvell/mvneta.c @@ -1721,6 +1721,7 @@ static int mvneta_tx(struct sk_buff *skb u16 txq_id = skb_get_queue_mapping(skb); struct mvneta_tx_queue *txq = &pp->txqs[txq_id]; struct mvneta_tx_desc *tx_desc; + int len = skb->len; int frags = 0; u32 tx_cmd; @@ -1788,7 +1789,7 @@ out: u64_stats_update_begin(&stats->syncp); stats->tx_packets++; - stats->tx_bytes += skb->len; + stats->tx_bytes += len; u64_stats_update_end(&stats->syncp); } else { dev->stats.tx_dropped++;