2017-11-09 14:08:08

by Pravin Shelar

[permalink] [raw]
Subject: Re: [ovs-dev] [PATCH] openvswitch: add null pointer check on upcall

On Thu, Nov 9, 2017 at 7:29 PM, Colin King <[email protected]> wrote:
> From: Colin Ian King <[email protected]>
>
> upcall may be assigned a NULL pointer as genlmsg_put can potentially
> return a NULL. Add a null check to avoid a null pointer dereference
> on upcall.
>
> Detected by CoverityScan, CID#728404 ("Dereference null return value")
>
> Fixes: commit ccb1352e76cf ("net: Add Open vSwitch kernel components.")
> Signed-off-by: Colin Ian King <[email protected]>
> ---
> net/openvswitch/datapath.c | 4 ++++
> 1 file changed, 4 insertions(+)
>
> diff --git a/net/openvswitch/datapath.c b/net/openvswitch/datapath.c
> index 4d38ac044cee..e8fb3d76fa6e 100644
> --- a/net/openvswitch/datapath.c
> +++ b/net/openvswitch/datapath.c
> @@ -461,6 +461,10 @@ static int queue_userspace_packet(struct datapath *dp, struct sk_buff *skb,
>
> upcall = genlmsg_put(user_skb, 0, 0, &dp_packet_genl_family,
> 0, upcall_info->cmd);
> + if (!upcall) {
> + err = -ENOBUFS;
> + goto out;
> + }
user_skb is allocated according to all required attributes, so
genlmsg_put() can not return null value.


> upcall->dp_ifindex = dp_ifindex;
>
> err = ovs_nla_put_key(key, key, OVS_PACKET_ATTR_KEY, false, user_skb);
> --
> 2.14.1
>
> _______________________________________________
> dev mailing list
> [email protected]
> https://mail.openvswitch.org/mailman/listinfo/ovs-dev

From 1583597262146487208@xxx Thu Nov 09 14:00:36 +0000 2017
X-GM-THRID: 1583597262146487208
X-Gmail-Labels: Inbox,Category Forums,HistoricalUnread