drivers/infiniband/ulp/ipoib/ipoib_main.c: use-after-free

[Adrian Bunk <bunk@stusta.de>]

The Coverity checker spotted the following code introduced by
commit 839fcaba355abaffb7b44f0f4504093acb0b11cf:

<--  snip  -->

...
static void path_rec_completion(int status,
                                struct ib_sa_path_rec *pathrec,
                                void *path_ptr)
{
...
                list_for_each_entry(neigh, &path->neigh_list, list) {
                        kref_get(&path->ah->ref);
                        neigh->ah = path->ah;
                        memcpy(&neigh->dgid.raw, &path->pathrec.dgid.raw,
                               sizeof(union ib_gid));

                        if (ipoib_cm_enabled(dev, neigh->neighbour)) {
                                if (!ipoib_cm_get(neigh))
                                        ipoib_cm_set(neigh, ipoib_cm_create_tx(dev,
                                                                               path,
                                                                               neigh));
                                if (!ipoib_cm_get(neigh)) {
                                        list_del(&neigh->list);
                                        if (neigh->ah)
                                                ipoib_put_ah(neigh->ah);
                                        ipoib_neigh_free(dev, neigh);
                                        continue;
                                }
                        }

                        while ((skb = __skb_dequeue(&neigh->queue)))
                                __skb_queue_tail(&skqueue, skb);
                }
...

<--  snip  -->

Notice that before the continue "neigh" gets freed, but the 
list_for_each_entry() for() loop uses it.

cu
Adrian

-- 

       "Is there not promise of rain?" Ling Tan asked suddenly out
        of the darkness. There had been need of rain for many days.
       "Only a promise," Lao Er said.
                                       Pearl S. Buck - Dragon Seed