From 77d8e1efea0e313edc710160c232a6fd2dc9f907 Mon Sep 17 00:00:00 2001 From: "Michael S. Tsirkin" Date: Wed, 21 Mar 2007 15:45:05 +0200 Subject: [PATCH] IB/ipoib: Fix thinko in packet length checks The packet length checks in ipoib are broken: we add 4 bytes (IPoIB encapsulation header) when sending a packet, not 20 bytes (hardware address length) to each packet. Therefore, if connected mode is enabled so that the interface MTU is larger than the multicast MTU, IPoIB may end up trying to send too-long multicast packets. For example, multicast is broken if a message of size 2048 bytes is sent on an interface with UD MTU 2048, because 2048 is bigger than the real limit of 2044 but the code tests against the wrong limit of 2060. This patch fixes , submitted by Scott Weitzenkamp . Signed-off-by: Michael S. Tsirkin Signed-off-by: Roland Dreier --- drivers/infiniband/ulp/ipoib/ipoib_cm.c | 2 +- drivers/infiniband/ulp/ipoib/ipoib_ib.c | 4 ++-- 2 files changed, 3 insertions(+), 3 deletions(-) diff --git a/drivers/infiniband/ulp/ipoib/ipoib_cm.c b/drivers/infiniband/ulp/ipoib/ipoib_cm.c index 467564074e9..e70492db74f 100644 --- a/drivers/infiniband/ulp/ipoib/ipoib_cm.c +++ b/drivers/infiniband/ulp/ipoib/ipoib_cm.c @@ -452,7 +452,7 @@ void ipoib_cm_send(struct net_device *dev, struct sk_buff *skb, struct ipoib_cm_ skb->len, tx->mtu); ++priv->stats.tx_dropped; ++priv->stats.tx_errors; - ipoib_cm_skb_too_long(dev, skb, tx->mtu - INFINIBAND_ALEN); + ipoib_cm_skb_too_long(dev, skb, tx->mtu - IPOIB_ENCAP_LEN); return; } diff --git a/drivers/infiniband/ulp/ipoib/ipoib_ib.c b/drivers/infiniband/ulp/ipoib/ipoib_ib.c index f2aa923ddbe..ba0ee5cf2ad 100644 --- a/drivers/infiniband/ulp/ipoib/ipoib_ib.c +++ b/drivers/infiniband/ulp/ipoib/ipoib_ib.c @@ -328,9 +328,9 @@ void ipoib_send(struct net_device *dev, struct sk_buff *skb, struct ipoib_tx_buf *tx_req; u64 addr; - if (unlikely(skb->len > priv->mcast_mtu + INFINIBAND_ALEN)) { + if (unlikely(skb->len > priv->mcast_mtu + IPOIB_ENCAP_LEN)) { ipoib_warn(priv, "packet len %d (> %d) too long to send, dropping\n", - skb->len, priv->mcast_mtu + INFINIBAND_ALEN); + skb->len, priv->mcast_mtu + IPOIB_ENCAP_LEN); ++priv->stats.tx_dropped; ++priv->stats.tx_errors; ipoib_cm_skb_too_long(dev, skb, priv->mcast_mtu); -- 2.41.1