From: Eric Dumazet <edumazet@google.com> mainline inclusion from mainline-v6.14-rc3 commit 90b2f49a502fa71090d9f4fe29a2f51fe5dff76d category: bugfix bugzilla: https://gitee.com/src-openeuler/kernel/issues/IBPC5W CVE: CVE-2025-21761 Reference: https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?i... -------------------------------- ovs_vport_cmd_fill_info() can be called without RTNL or RCU. Use RCU protection and dev_net_rcu() to avoid potential UAF. Fixes: 9354d4520342 ("openvswitch: reliable interface indentification in port dumps") Signed-off-by: Eric Dumazet <edumazet@google.com> Reviewed-by: Kuniyuki Iwashima <kuniyu@amazon.com> Link: https://patch.msgid.link/20250207135841.1948589-6-edumazet@google.com Signed-off-by: Jakub Kicinski <kuba@kernel.org> Signed-off-by: Dong Chenchen <dongchenchen2@huawei.com> --- net/openvswitch/datapath.c | 12 +++++++++--- 1 file changed, 9 insertions(+), 3 deletions(-) diff --git a/net/openvswitch/datapath.c b/net/openvswitch/datapath.c index b625ab5e9a43..b493931433e9 100644 --- a/net/openvswitch/datapath.c +++ b/net/openvswitch/datapath.c @@ -1980,6 +1980,7 @@ static int ovs_vport_cmd_fill_info(struct vport *vport, struct sk_buff *skb, { struct ovs_header *ovs_header; struct ovs_vport_stats vport_stats; + struct net *net_vport; int err; ovs_header = genlmsg_put(skb, portid, seq, &dp_vport_genl_family, @@ -1996,12 +1997,15 @@ static int ovs_vport_cmd_fill_info(struct vport *vport, struct sk_buff *skb, nla_put_u32(skb, OVS_VPORT_ATTR_IFINDEX, vport->dev->ifindex)) goto nla_put_failure; - if (!net_eq(net, dev_net(vport->dev))) { - int id = peernet2id_alloc(net, dev_net(vport->dev), gfp); + rcu_read_lock(); + net_vport = dev_net_rcu(vport->dev); + if (!net_eq(net, net_vport)) { + int id = peernet2id_alloc(net, net_vport, GFP_ATOMIC); if (nla_put_s32(skb, OVS_VPORT_ATTR_NETNSID, id)) - goto nla_put_failure; + goto nla_put_failure_unlock; } + rcu_read_unlock(); ovs_vport_get_stats(vport, &vport_stats); if (nla_put_64bit(skb, OVS_VPORT_ATTR_STATS, @@ -2019,6 +2023,8 @@ static int ovs_vport_cmd_fill_info(struct vport *vport, struct sk_buff *skb, genlmsg_end(skb, ovs_header); return 0; +nla_put_failure_unlock: + rcu_read_unlock(); nla_put_failure: err = -EMSGSIZE; error: -- 2.25.1