From d6fb3be544b46a7611a3373fcaa62b5b0be01888 Mon Sep 17 00:00:00 2001 From: Rob Herring Date: Wed, 16 Jan 2013 13:36:37 +0000 Subject: [PATCH] net: calxedaxgmac: throw away overrun frames The xgmac driver assumes 1 frame per descriptor. If a frame larger than the descriptor's buffer size is received, the frame will spill over into the next descriptor. So check for received frames that span more than one descriptor and discard them. This prevents a crash if we receive erroneous large packets. Signed-off-by: Rob Herring Cc: netdev@vger.kernel.org Cc: linux-kernel@vger.kernel.org Signed-off-by: David S. Miller --- drivers/net/ethernet/calxeda/xgmac.c | 4 ++++ 1 file changed, 4 insertions(+) diff --git a/drivers/net/ethernet/calxeda/xgmac.c b/drivers/net/ethernet/calxeda/xgmac.c index b407043..f7f0290 100644 --- a/drivers/net/ethernet/calxeda/xgmac.c +++ b/drivers/net/ethernet/calxeda/xgmac.c @@ -548,6 +548,10 @@ static int desc_get_rx_status(struct xgmac_priv *priv, struct xgmac_dma_desc *p) return -1; } + /* All frames should fit into a single buffer */ + if (!(status & RXDESC_FIRST_SEG) || !(status & RXDESC_LAST_SEG)) + return -1; + /* Check if packet has checksum already */ if ((status & RXDESC_FRAME_TYPE) && (status & RXDESC_EXT_STATUS) && !(ext_status & RXDESC_IP_PAYLOAD_MASK)) -- 2.7.4