[ovs-dev] [PATCH] odp-util: Fix a null pointer dereference in odp_nsh_key_from_attr__()

[Yunjian Wang]

This patch fixes (dereference after null check) coverity issue.
We should add null check of 'nsh_mask' to avoid passing NULL pointer
to memcpy() because the 'nsh_mask' maybe null.

Addresses-Coverity: ("Dereference after null check")
Fixes: 81fdabb94dd7 ("nsh: fix nested mask for OVS_KEY_ATTR_NSH")
Cc: Yi Yang <yi.y.yang at intel.com>
Signed-off-by: Yunjian Wang <wangyunjian at huawei.com>
---
 lib/odp-util.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/lib/odp-util.c b/lib/odp-util.c
index 7729a9060..9356bbf6e 100644
--- a/lib/odp-util.c
+++ b/lib/odp-util.c
@@ -2941,7 +2941,7 @@ odp_nsh_key_from_attr__(const struct nlattr *attr, bool is_mask,
             const struct ovs_nsh_key_md1 *md1 = nl_attr_get(a);
             has_md1 = true;
             memcpy(nsh->context, md1->context, sizeof md1->context);
-            if (len == 2 * sizeof(*md1)) {
+            if (nsh_mask && (len == 2 * sizeof(*md1))) {
                 const struct ovs_nsh_key_md1 *md1_mask = md1 + 1;
                 memcpy(nsh_mask->context, md1_mask->context,
                        sizeof(*md1_mask));
-- 
2.18.1