From 9eea9515cb5f3a4416511ef54b1cc98ca04869a1 Mon Sep 17 00:00:00 2001 From: "Eric W. Biederman" Date: Fri, 25 May 2012 10:42:54 -0600 Subject: [PATCH] userns: nfnetlink_log: Report socket uids in the log sockets user namespace At logging instance creation capture the peer netlink socket's user namespace. Use the captured peer user namespace when reporting socket uids to the peer. The peer socket's user namespace is guaranateed to be valid until the user closes the netlink socket. nfnetlink_log removes instances during the final close of a socket. __build_packet_message does not get called after an instance is destroyed. Therefore it is safe to let the peer netlink socket take care of the user namespace reference counting for us. Acked-by: David S. Miller Acked-by: Serge Hallyn Signed-off-by: Eric W. Biederman --- init/Kconfig | 1 - net/netfilter/nfnetlink_log.c | 14 ++++++++++---- 2 files changed, 10 insertions(+), 5 deletions(-) diff --git a/init/Kconfig b/init/Kconfig index 07435e0c3a4b..2660b312ae9d 100644 --- a/init/Kconfig +++ b/init/Kconfig @@ -947,7 +947,6 @@ config UIDGID_CONVERTED depends on NETFILTER_XT_MATCH_OWNER = n depends on NETFILTER_XT_MATCH_RECENT = n depends on NETFILTER_XT_TARGET_LOG = n - depends on NETFILTER_NETLINK_LOG = n depends on AF_RXRPC = n depends on NET_KEY = n depends on DNS_RESOLVER = n diff --git a/net/netfilter/nfnetlink_log.c b/net/netfilter/nfnetlink_log.c index 169ab59ed9d4..4142aac17c3c 100644 --- a/net/netfilter/nfnetlink_log.c +++ b/net/netfilter/nfnetlink_log.c @@ -55,6 +55,7 @@ struct nfulnl_instance { unsigned int qlen; /* number of nlmsgs in skb */ struct sk_buff *skb; /* pre-allocatd skb */ struct timer_list timer; + struct user_namespace *peer_user_ns; /* User namespace of the peer process */ int peer_pid; /* PID of the peer process */ /* configurable parameters */ @@ -132,7 +133,7 @@ instance_put(struct nfulnl_instance *inst) static void nfulnl_timer(unsigned long data); static struct nfulnl_instance * -instance_create(u_int16_t group_num, int pid) +instance_create(u_int16_t group_num, int pid, struct user_namespace *user_ns) { struct nfulnl_instance *inst; int err; @@ -162,6 +163,7 @@ instance_create(u_int16_t group_num, int pid) setup_timer(&inst->timer, nfulnl_timer, (unsigned long)inst); + inst->peer_user_ns = user_ns; inst->peer_pid = pid; inst->group_num = group_num; @@ -503,8 +505,11 @@ __build_packet_message(struct nfulnl_instance *inst, read_lock_bh(&skb->sk->sk_callback_lock); if (skb->sk->sk_socket && skb->sk->sk_socket->file) { struct file *file = skb->sk->sk_socket->file; - __be32 uid = htonl(file->f_cred->fsuid); - __be32 gid = htonl(file->f_cred->fsgid); + __be32 uid = htonl(from_kuid_munged(inst->peer_user_ns, + file->f_cred->fsuid)); + __be32 gid = htonl(from_kgid_munged(inst->peer_user_ns, + file->f_cred->fsgid)); + /* need to unlock here since NLA_PUT may goto */ read_unlock_bh(&skb->sk->sk_callback_lock); if (nla_put_be32(inst->skb, NFULA_UID, uid) || nla_put_be32(inst->skb, NFULA_GID, gid)) @@ -783,7 +788,8 @@ nfulnl_recv_config(struct sock *ctnl, struct sk_buff *skb, } inst = instance_create(group_num, - NETLINK_CB(skb).pid); + NETLINK_CB(skb).pid, + sk_user_ns(NETLINK_CB(skb).ssk)); if (IS_ERR(inst)) { ret = PTR_ERR(inst); goto out; -- GitLab