5.4-stable review patch. If anyone has any objections, please let me know.
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From: Lin Ma linma@zju.edu.cn
[ Upstream commit 6c21660fe221a15c789dee2bc2fd95516bc5aeaf ]
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 linma@zju.edu.cn Reviewed-by: Simon Horman horms@kernel.org Link: https://lore.kernel.org/r/20240118130306.1644001-1-linma@zju.edu.cn Signed-off-by: Jakub Kicinski kuba@kernel.org Signed-off-by: Sasha Levin sashal@kernel.org --- 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 0db85aeb119b..99b277775257 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)