[PATCH 4.9 20/59] drop_monitor: consider inserted data in genlmsg_end

From: Greg Kroah-Hartman
Date: Fri Jan 13 2017 - 07:15:14 EST


4.9-stable review patch. If anyone has any objections, please let me know.

------------------

From: Reiter Wolfgang <wr0112358@xxxxxxxxx>


[ Upstream commit 3b48ab2248e61408910e792fe84d6ec466084c1a ]

Final nlmsg_len field update must reflect inserted net_dm_drop_point
data.

This patch depends on previous patch:
"drop_monitor: add missing call to genlmsg_end"

Signed-off-by: Reiter Wolfgang <wr0112358@xxxxxxxxx>
Acked-by: Neil Horman <nhorman@xxxxxxxxxxxxx>
Signed-off-by: David S. Miller <davem@xxxxxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
net/core/drop_monitor.c | 8 +++++++-
1 file changed, 7 insertions(+), 1 deletion(-)

--- a/net/core/drop_monitor.c
+++ b/net/core/drop_monitor.c
@@ -107,7 +107,6 @@ static struct sk_buff *reset_per_cpu_dat
}
msg = nla_data(nla);
memset(msg, 0, al);
- genlmsg_end(skb, msg_header);
goto out;

err:
@@ -117,6 +116,13 @@ out:
swap(data->skb, skb);
spin_unlock_irqrestore(&data->lock, flags);

+ if (skb) {
+ struct nlmsghdr *nlh = (struct nlmsghdr *)skb->data;
+ struct genlmsghdr *gnlh = (struct genlmsghdr *)nlmsg_data(nlh);
+
+ genlmsg_end(skb, genlmsg_data(gnlh));
+ }
+
return skb;
}