net: sched: initialize with 0 before setting erspan md->u

In fl_set_erspan_opt(), all bits of erspan md was set 1, as this
function is also used to set opt MASK. However, when setting for
md->u.index for opt VALUE, the rest bits of the union md->u will
be left 1. It would cause to fail the match of the whole md when
version is 1 and only index is set.

This patch is to fix by initializing with 0 before setting erspan
md->u.

Reported-by: Shuang Li <shuali@redhat.com>
Fixes: 79b1011cb33d ("net: sched: allow flower to match erspan options")
Signed-off-by: Xin Long <lucien.xin@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

diff --git a/net/sched/cls_flower.c b/net/sched/cls_flower.c
index e8fda1bd4d9df713d8fe86b704f87e13d50e4c15..fed18fd2c50ba9f85db1f35659ff911ec080f13c 100644 (file)
--- a/net/sched/cls_flower.c
+++ b/net/sched/cls_flower.c
@@ -1223,6 +1223,7 @@ static int fl_set_erspan_opt(const struct nlattr *nla, struct fl_flow_key *key,
                }
                if (tb[TCA_FLOWER_KEY_ENC_OPT_ERSPAN_INDEX]) {
                        nla = tb[TCA_FLOWER_KEY_ENC_OPT_ERSPAN_INDEX];
+                       memset(&md->u, 0x00, sizeof(md->u));
                        md->u.index = nla_get_be32(nla);
                }
        } else if (md->version == 2) {