integrity: ima iint radix_tree_lookup locking fix

Based on Andrew Morton's comments:
- add missing locks around radix_tree_lookup in ima_iint_insert()
Signed-off-by: NMimi Zohar <zohar@us.ibm.com>
Cc: James Morris <jmorris@namei.org>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NJames Morris <jmorris@namei.org>

security/integrity/ima/ima_iint.c

@@ -73,8 +73,10 @@ struct ima_iint_cache *ima_iint_insert(struct inode *inode)
 	if (rc < 0) {
 		kmem_cache_free(iint_cache, iint);
 		if (rc == -EEXIST) {
+			spin_lock(&ima_iint_lock);
 			iint = radix_tree_lookup(&ima_iint_store,
 						 (unsigned long)inode);
+			spin_unlock(&ima_iint_lock);
 		} else
 			iint = NULL;
 	}