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authorZhouyi Zhou <zhouzhouyi@gmail.com>2013-03-14 17:21:50 +0000
committerDavid S. Miller <davem@davemloft.net>2013-03-15 09:06:58 -0400
commitaaa0c23cb90141309f5076ba5e3bfbd39544b985 (patch)
treeb6aa0989e463fbc803474c077e5a3ab512017024
parent1e731cb986d564c4938bcba89ff5f4aea1d8e2fb (diff)
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Fix dst_neigh_lookup/dst_neigh_lookup_skb return value handling bug
When neighbour table is full, dst_neigh_lookup/dst_neigh_lookup_skb will return -ENOBUFS which is absolutely non zero, while all the code in kernel which use above functions assume failure only on zero return which will cause panic. (for example: : https://bugzilla.kernel.org/show_bug.cgi?id=54731). This patch corrects above error with smallest changes to kernel source code and also correct two return value check missing bugs in drivers/infiniband/hw/cxgb4/cm.c Tested on my x86_64 SMP machine Reported-by: Zhouyi Zhou <zhouzhouyi@gmail.com> Tested-by: Zhouyi Zhou <zhouzhouyi@gmail.com> Signed-off-by: Zhouyi Zhou <zhouzhouyi@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
-rw-r--r--drivers/infiniband/hw/cxgb4/cm.c12
-rw-r--r--include/net/dst.h6
2 files changed, 16 insertions, 2 deletions
diff --git a/drivers/infiniband/hw/cxgb4/cm.c b/drivers/infiniband/hw/cxgb4/cm.c
index 565bfb161c1a..a3fde52840ca 100644
--- a/drivers/infiniband/hw/cxgb4/cm.c
+++ b/drivers/infiniband/hw/cxgb4/cm.c
@@ -1575,6 +1575,12 @@ static int c4iw_reconnect(struct c4iw_ep *ep)
neigh = dst_neigh_lookup(ep->dst,
&ep->com.cm_id->remote_addr.sin_addr.s_addr);
+ if (!neigh) {
+ pr_err("%s - cannot alloc neigh.\n", __func__);
+ err = -ENOMEM;
+ goto fail4;
+ }
+
/* get a l2t entry */
if (neigh->dev->flags & IFF_LOOPBACK) {
PDBG("%s LOOPBACK\n", __func__);
@@ -3053,6 +3059,12 @@ static int rx_pkt(struct c4iw_dev *dev, struct sk_buff *skb)
dst = &rt->dst;
neigh = dst_neigh_lookup_skb(dst, skb);
+ if (!neigh) {
+ pr_err("%s - failed to allocate neigh!\n",
+ __func__);
+ goto free_dst;
+ }
+
if (neigh->dev->flags & IFF_LOOPBACK) {
pdev = ip_dev_find(&init_net, iph->daddr);
e = cxgb4_l2t_get(dev->rdev.lldi.l2t, neigh,
diff --git a/include/net/dst.h b/include/net/dst.h
index 853cda11e518..1f8fd109e225 100644
--- a/include/net/dst.h
+++ b/include/net/dst.h
@@ -413,13 +413,15 @@ static inline int dst_neigh_output(struct dst_entry *dst, struct neighbour *n,
static inline struct neighbour *dst_neigh_lookup(const struct dst_entry *dst, const void *daddr)
{
- return dst->ops->neigh_lookup(dst, NULL, daddr);
+ struct neighbour *n = dst->ops->neigh_lookup(dst, NULL, daddr);
+ return IS_ERR(n) ? NULL : n;
}
static inline struct neighbour *dst_neigh_lookup_skb(const struct dst_entry *dst,
struct sk_buff *skb)
{
- return dst->ops->neigh_lookup(dst, skb, NULL);
+ struct neighbour *n = dst->ops->neigh_lookup(dst, skb, NULL);
+ return IS_ERR(n) ? NULL : n;
}
static inline void dst_link_failure(struct sk_buff *skb)