IPoIB: In unicast_arp_send(), only free newly-created paths
If path_rec_start() returns error, call path_free() only if the path
was newly-created. If we free an existing path whose valid flag was zero,
(but do not detach it from the list) we cause corruption of the
path list (of which it is a member), and get a kernel crash.
The simplest solution is to not free an existing path -- just leave it
in the list as-is (i.e., with its valid flag cleared).
Thanks to Yossi Etigin of Voltaire for identifying the problem flow
which caused the kernel crash.
Signed-off-by: Jack Morgenstein <jackm@dev.mellanox.co.il>
Signed-off-by: Moni Shua <monis@voltaire.com>
Signed-off-by: Roland Dreier <rolandd@cisco.com>
diff --git a/drivers/infiniband/ulp/ipoib/ipoib_main.c b/drivers/infiniband/ulp/ipoib/ipoib_main.c
index 0bd2a4f..353c13b 100644
--- a/drivers/infiniband/ulp/ipoib/ipoib_main.c
+++ b/drivers/infiniband/ulp/ipoib/ipoib_main.c
@@ -660,8 +660,12 @@
path = __path_find(dev, phdr->hwaddr + 4);
if (!path || !path->valid) {
- if (!path)
+ int new_path = 0;
+
+ if (!path) {
path = path_rec_create(dev, phdr->hwaddr + 4);
+ new_path = 1;
+ }
if (path) {
/* put pseudoheader back on for next time */
skb_push(skb, sizeof *phdr);
@@ -669,7 +673,8 @@
if (!path->query && path_rec_start(dev, path)) {
spin_unlock_irqrestore(&priv->lock, flags);
- path_free(dev, path);
+ if (new_path)
+ path_free(dev, path);
return;
} else
__path_add(dev, path);