2024-01-18 13:03:45

by Lin Ma

[permalink] [raw]
Subject: [PATCH net v2] vlan: skip nested type that is not IFLA_VLAN_QOS_MAPPING

In the vlan_changelink function, a loop is used to parse the nested
attributes IFLA_VLAN_EGRESS_QOS and IFLA_VLAN_INGRESS_QOS in order to
obtain the struct ifla_vlan_qos_mapping. These two nested attributes are
checked in the vlan_validate_qos_map function, which calls
nla_validate_nested_deprecated with the vlan_map_policy.

However, this deprecated validator applies a LIBERAL strictness, allowing
the presence of an attribute with the type IFLA_VLAN_QOS_UNSPEC.
Consequently, the loop in vlan_changelink may parse an attribute of type
IFLA_VLAN_QOS_UNSPEC and believe it carries a payload of
struct ifla_vlan_qos_mapping, which is not necessarily true.

To address this issue and ensure compatibility, this patch introduces two
type checks that skip attributes whose type is not IFLA_VLAN_QOS_MAPPING.

Fixes: 07b5b17e157b ("[VLAN]: Use rtnl_link API")
Signed-off-by: Lin Ma <[email protected]>
---
V1 -> V2: make net-next to net as suggested by Paolo
and add Fixes tag for this one

net/8021q/vlan_netlink.c | 4 ++++
1 file changed, 4 insertions(+)

diff --git a/net/8021q/vlan_netlink.c b/net/8021q/vlan_netlink.c
index 214532173536..a3b68243fd4b 100644
--- a/net/8021q/vlan_netlink.c
+++ b/net/8021q/vlan_netlink.c
@@ -118,12 +118,16 @@ static int vlan_changelink(struct net_device *dev, struct nlattr *tb[],
}
if (data[IFLA_VLAN_INGRESS_QOS]) {
nla_for_each_nested(attr, data[IFLA_VLAN_INGRESS_QOS], rem) {
+ if (nla_type(attr) != IFLA_VLAN_QOS_MAPPING)
+ continue;
m = nla_data(attr);
vlan_dev_set_ingress_priority(dev, m->to, m->from);
}
}
if (data[IFLA_VLAN_EGRESS_QOS]) {
nla_for_each_nested(attr, data[IFLA_VLAN_EGRESS_QOS], rem) {
+ if (nla_type(attr) != IFLA_VLAN_QOS_MAPPING)
+ continue;
m = nla_data(attr);
err = vlan_dev_set_egress_priority(dev, m->from, m->to);
if (err)
--
2.17.1



2024-01-19 15:45:11

by Simon Horman

[permalink] [raw]
Subject: Re: [PATCH net v2] vlan: skip nested type that is not IFLA_VLAN_QOS_MAPPING

On Thu, Jan 18, 2024 at 09:03:06PM +0800, Lin Ma wrote:
> In the vlan_changelink function, a loop is used to parse the nested
> attributes IFLA_VLAN_EGRESS_QOS and IFLA_VLAN_INGRESS_QOS in order to
> obtain the struct ifla_vlan_qos_mapping. These two nested attributes are
> checked in the vlan_validate_qos_map function, which calls
> nla_validate_nested_deprecated with the vlan_map_policy.
>
> However, this deprecated validator applies a LIBERAL strictness, allowing
> the presence of an attribute with the type IFLA_VLAN_QOS_UNSPEC.
> Consequently, the loop in vlan_changelink may parse an attribute of type
> IFLA_VLAN_QOS_UNSPEC and believe it carries a payload of
> struct ifla_vlan_qos_mapping, which is not necessarily true.
>
> To address this issue and ensure compatibility, this patch introduces two
> type checks that skip attributes whose type is not IFLA_VLAN_QOS_MAPPING.
>
> Fixes: 07b5b17e157b ("[VLAN]: Use rtnl_link API")
> Signed-off-by: Lin Ma <[email protected]>
> ---
> V1 -> V2: make net-next to net as suggested by Paolo
> and add Fixes tag for this one

Reviewed-by: Simon Horman <[email protected]>


2024-01-20 05:30:41

by patchwork-bot+netdevbpf

[permalink] [raw]
Subject: Re: [PATCH net v2] vlan: skip nested type that is not IFLA_VLAN_QOS_MAPPING

Hello:

This patch was applied to netdev/net.git (main)
by Jakub Kicinski <[email protected]>:

On Thu, 18 Jan 2024 21:03:06 +0800 you wrote:
> In the vlan_changelink function, a loop is used to parse the nested
> attributes IFLA_VLAN_EGRESS_QOS and IFLA_VLAN_INGRESS_QOS in order to
> obtain the struct ifla_vlan_qos_mapping. These two nested attributes are
> checked in the vlan_validate_qos_map function, which calls
> nla_validate_nested_deprecated with the vlan_map_policy.
>
> However, this deprecated validator applies a LIBERAL strictness, allowing
> the presence of an attribute with the type IFLA_VLAN_QOS_UNSPEC.
> Consequently, the loop in vlan_changelink may parse an attribute of type
> IFLA_VLAN_QOS_UNSPEC and believe it carries a payload of
> struct ifla_vlan_qos_mapping, which is not necessarily true.
>
> [...]

Here is the summary with links:
- [net,v2] vlan: skip nested type that is not IFLA_VLAN_QOS_MAPPING
https://git.kernel.org/netdev/net/c/6c21660fe221

You are awesome, thank you!
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