net: missing lock releases in ipmr_base.c

In method mr_mfc_seq_idx, the lock it->lock and rcu_read_lock are not released when pos-- == 0 is true.

Signed-off-by: Ryan Cai <ycaibb@gmail.com>

net/ipv4/ipmr_base.c

@@ -154,13 +154,15 @@ void *mr_mfc_seq_idx(struct net *net,
 	it->cache = &mrt->mfc_cache_list;
 	list_for_each_entry_rcu(mfc, &mrt->mfc_cache_list, list)
 		if (pos-- == 0)
+			rcu_read_unlock();
 			return mfc;
 	rcu_read_unlock();
 
 	spin_lock_bh(it->lock);
 	it->cache = &mrt->mfc_unres_queue;
 	list_for_each_entry(mfc, it->cache, list)
 		if (pos-- == 0)
+			spin_unlock_bh(it->lock);
 			return mfc;
 	spin_unlock_bh(it->lock);