[PATCH 5.8 22/56] net: sched: initialize with 0 before setting erspan md->u

From: Greg Kroah-Hartman
Date: Fri Sep 25 2020 - 08:49:19 EST


From: Xin Long <lucien.xin@xxxxxxxxx>

[ Upstream commit 8e1b3ac4786680c2d2b5a24e38a2d714c3bcd1ef ]

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@xxxxxxxxxx>
Fixes: 79b1011cb33d ("net: sched: allow flower to match erspan options")
Signed-off-by: Xin Long <lucien.xin@xxxxxxxxx>
Signed-off-by: David S. Miller <davem@xxxxxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
net/sched/cls_flower.c | 1 +
1 file changed, 1 insertion(+)

--- a/net/sched/cls_flower.c
+++ b/net/sched/cls_flower.c
@@ -1215,6 +1215,7 @@ static int fl_set_erspan_opt(const struc
}
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) {