On Mon, Jan 12, 2026 at 07:11:10PM -0800, Bobby Eshleman wrote:
> From: Bobby Eshleman <[email protected]>
>
> Add netns logic to vsock core. Additionally, modify transport hook
> prototypes to be used by later transport-specific patches (e.g.,
> *_seqpacket_allow()).
>
> Namespaces are supported primarily by changing socket lookup functions
> (e.g., vsock_find_connected_socket()) to take into account the socket
> namespace and the namespace mode before considering a candidate socket a
> "match".
>
> This patch also introduces the sysctl /proc/sys/net/vsock/ns_mode to
> report the mode and /proc/sys/net/vsock/child_ns_mode to set the mode
> for new namespaces.
>
> Add netns functionality (initialization, passing to transports, procfs,
> etc...) to the af_vsock socket layer. Later patches that add netns
> support to transports depend on this patch.
>
> dgram_allow(), stream_allow(), and seqpacket_allow() callbacks are
> modified to take a vsk in order to perform logic on namespace modes. In
> future patches, the net will also be used for socket
> lookups in these functions.
>
> Signed-off-by: Bobby Eshleman <[email protected]>
> ---
> Changes in v14:
> - include linux/sysctl.h in af_vsock.c
> - squash patch 'vsock: add per-net vsock NS mode state' into this patch
> (prior version can be found here):
>
> https://lore.kernel.org/all/[email protected]/)
So, about the static port, are you going to address it in
the next version then?
> Changes in v13:
> - remove net_mode and replace with direct accesses to net->vsock.mode,
> since this is now immutable.
> - update comments about mode behavior and mutability, and sysctl API
> - only pass NULL for net when wanting global, instead of net_mode ==
> VSOCK_NET_MODE_GLOBAL. This reflects the new logic
> of vsock_net_check_mode() that only requires net pointers (not
> net_mode).
> - refactor sysctl string code into a re-usable function, because
> child_ns_mode and ns_mode both handle the same strings.
> - remove redundant vsock_net_init(&init_net) call in module init because
> pernet registration calls the callback on the init_net too
>
> Changes in v12:
> - return true in dgram_allow(), stream_allow(), and seqpacket_allow()
> only if net_mode == VSOCK_NET_MODE_GLOBAL (Stefano)
> - document bind(VMADDR_CID_ANY) case in af_vsock.c (Stefano)
> - change order of stream_allow() call in vmci so we can pass vsk
> to it
>
> Changes in v10:
> - add file-level comment about what happens to sockets/devices
> when the namespace mode changes (Stefano)
> - change the 'if (write)' boolean in vsock_net_mode_string() to
> if (!write), this simplifies a later patch which adds "goto"
> for mutex unlocking on function exit.
>
> Changes in v9:
> - remove virtio_vsock_alloc_rx_skb() (Stefano)
> - remove vsock_global_dummy_net, not needed as net=NULL +
> net_mode=VSOCK_NET_MODE_GLOBAL achieves identical result
>
> Changes in v7:
> - hv_sock: fix hyperv build error
> - explain why vhost does not use the dummy
> - explain usage of __vsock_global_dummy_net
> - explain why VSOCK_NET_MODE_STR_MAX is 8 characters
> - use switch-case in vsock_net_mode_string()
> - avoid changing transports as much as possible
> - add vsock_find_{bound,connected}_socket_net()
> - rename `vsock_hdr` to `sysctl_hdr`
> - add virtio_vsock_alloc_linear_skb() wrapper for setting dummy net and
> global mode for virtio-vsock, move skb->cb zero-ing into wrapper
> - explain seqpacket_allow() change
> - move net setting to __vsock_create() instead of vsock_create() so
> that child sockets also have their net assigned upon accept()
>
> Changes in v6:
> - unregister sysctl ops in vsock_exit()
> - af_vsock: clarify description of CID behavior
> - af_vsock: fix buf vs buffer naming, and length checking
> - af_vsock: fix length checking w/ correct ctl_table->maxlen
>
> Changes in v5:
> - vsock_global_net() -> vsock_global_dummy_net()
> - update comments for new uAPI
> - use /proc/sys/net/vsock/ns_mode instead of /proc/net/vsock_ns_mode
> - add prototype changes so patch remains compilable
> ---
> MAINTAINERS | 1 +
> drivers/vhost/vsock.c | 6 +-
> include/linux/virtio_vsock.h | 4 +-
> include/net/af_vsock.h | 53 +++++-
> include/net/net_namespace.h | 4 +
> include/net/netns/vsock.h | 17 ++
> net/vmw_vsock/af_vsock.c | 297
> +++++++++++++++++++++++++++++---
> net/vmw_vsock/hyperv_transport.c | 7 +-
> net/vmw_vsock/virtio_transport.c | 9 +-
> net/vmw_vsock/virtio_transport_common.c | 6 +-
> net/vmw_vsock/vmci_transport.c | 26 ++-
> net/vmw_vsock/vsock_loopback.c | 8 +-
> 12 files changed, 394 insertions(+), 44 deletions(-)
>
> diff --git a/MAINTAINERS b/MAINTAINERS
> index 6737aad729d6..f4aa476427c8 100644
> --- a/MAINTAINERS
> +++ b/MAINTAINERS
> @@ -27522,6 +27522,7 @@ L: [email protected]
> S: Maintained
> F: drivers/vhost/vsock.c
> F: include/linux/virtio_vsock.h
> +F: include/net/netns/vsock.h
> F: include/uapi/linux/virtio_vsock.h
> F: net/vmw_vsock/virtio_transport.c
> F: net/vmw_vsock/virtio_transport_common.c
> diff --git a/drivers/vhost/vsock.c b/drivers/vhost/vsock.c
> index 552cfb53498a..647ded6f6ea5 100644
> --- a/drivers/vhost/vsock.c
> +++ b/drivers/vhost/vsock.c
> @@ -407,7 +407,8 @@ static bool vhost_transport_msgzerocopy_allow(void)
> return true;
> }
>
> -static bool vhost_transport_seqpacket_allow(u32 remote_cid);
> +static bool vhost_transport_seqpacket_allow(struct vsock_sock *vsk,
> + u32 remote_cid);
>
> static struct virtio_transport vhost_transport = {
> .transport = {
> @@ -463,7 +464,8 @@ static struct virtio_transport vhost_transport = {
> .send_pkt = vhost_transport_send_pkt,
> };
>
> -static bool vhost_transport_seqpacket_allow(u32 remote_cid)
> +static bool vhost_transport_seqpacket_allow(struct vsock_sock *vsk,
> + u32 remote_cid)
> {
> struct vhost_vsock *vsock;
> bool seqpacket_allow = false;
> diff --git a/include/linux/virtio_vsock.h b/include/linux/virtio_vsock.h
> index 0c67543a45c8..1845e8d4f78d 100644
> --- a/include/linux/virtio_vsock.h
> +++ b/include/linux/virtio_vsock.h
> @@ -256,10 +256,10 @@ void virtio_transport_notify_buffer_size(struct
> vsock_sock *vsk, u64 *val);
>
> u64 virtio_transport_stream_rcvhiwat(struct vsock_sock *vsk);
> bool virtio_transport_stream_is_active(struct vsock_sock *vsk);
> -bool virtio_transport_stream_allow(u32 cid, u32 port);
> +bool virtio_transport_stream_allow(struct vsock_sock *vsk, u32 cid, u32
> port);
> int virtio_transport_dgram_bind(struct vsock_sock *vsk,
> struct sockaddr_vm *addr);
> -bool virtio_transport_dgram_allow(u32 cid, u32 port);
> +bool virtio_transport_dgram_allow(struct vsock_sock *vsk, u32 cid, u32 port);
>
> int virtio_transport_connect(struct vsock_sock *vsk);
>
> diff --git a/include/net/af_vsock.h b/include/net/af_vsock.h
> index d40e978126e3..10c2846fcc58 100644
> --- a/include/net/af_vsock.h
> +++ b/include/net/af_vsock.h
> @@ -10,6 +10,7 @@
>
> #include <linux/kernel.h>
> #include <linux/workqueue.h>
> +#include <net/netns/vsock.h>
> #include <net/sock.h>
> #include <uapi/linux/vm_sockets.h>
>
> @@ -124,7 +125,7 @@ struct vsock_transport {
> size_t len, int flags);
> int (*dgram_enqueue)(struct vsock_sock *, struct sockaddr_vm *,
> struct msghdr *, size_t len);
> - bool (*dgram_allow)(u32 cid, u32 port);
> + bool (*dgram_allow)(struct vsock_sock *vsk, u32 cid, u32 port);
>
> /* STREAM. */
> /* TODO: stream_bind() */
> @@ -136,14 +137,14 @@ struct vsock_transport {
> s64 (*stream_has_space)(struct vsock_sock *);
> u64 (*stream_rcvhiwat)(struct vsock_sock *);
> bool (*stream_is_active)(struct vsock_sock *);
> - bool (*stream_allow)(u32 cid, u32 port);
> + bool (*stream_allow)(struct vsock_sock *vsk, u32 cid, u32 port);
>
> /* SEQ_PACKET. */
> ssize_t (*seqpacket_dequeue)(struct vsock_sock *vsk, struct msghdr *msg,
> int flags);
> int (*seqpacket_enqueue)(struct vsock_sock *vsk, struct msghdr *msg,
> size_t len);
> - bool (*seqpacket_allow)(u32 remote_cid);
> + bool (*seqpacket_allow)(struct vsock_sock *vsk, u32 remote_cid);
> u32 (*seqpacket_has_data)(struct vsock_sock *vsk);
>
> /* Notification. */
> @@ -216,6 +217,11 @@ void vsock_remove_connected(struct vsock_sock *vsk);
> struct sock *vsock_find_bound_socket(struct sockaddr_vm *addr);
> struct sock *vsock_find_connected_socket(struct sockaddr_vm *src,
> struct sockaddr_vm *dst);
> +struct sock *vsock_find_bound_socket_net(struct sockaddr_vm *addr,
> + struct net *net);
> +struct sock *vsock_find_connected_socket_net(struct sockaddr_vm *src,
> + struct sockaddr_vm *dst,
> + struct net *net);
> void vsock_remove_sock(struct vsock_sock *vsk);
> void vsock_for_each_connected_socket(struct vsock_transport *transport,
> void (*fn)(struct sock *sk));
> @@ -256,4 +262,45 @@ static inline bool vsock_msgzerocopy_allow(const struct
> vsock_transport *t)
> {
> return t->msgzerocopy_allow && t->msgzerocopy_allow();
> }
> +
> +static inline enum vsock_net_mode vsock_net_mode(struct net *net)
> +{
> + return READ_ONCE(net->vsock.mode);
> +}
> +
> +static inline void vsock_net_set_child_mode(struct net *net,
> + enum vsock_net_mode mode)
> +{
> + WRITE_ONCE(net->vsock.child_ns_mode, mode);
> +}
> +
> +static inline enum vsock_net_mode vsock_net_child_mode(struct net *net)
> +{
> + return READ_ONCE(net->vsock.child_ns_mode);
> +}
> +
> +/* Return true if two namespaces pass the mode rules. Otherwise, return
> false.
> + *
> + * A NULL namespace is treated as VSOCK_NET_MODE_GLOBAL.
> + *
> + * Read more about modes in the comment header of net/vmw_vsock/af_vsock.c.
> + */
> +static inline bool vsock_net_check_mode(struct net *ns0, struct net *ns1)
> +{
> + enum vsock_net_mode mode0, mode1;
> +
> + /* Any vsocks within the same network namespace are always reachable,
> + * regardless of the mode.
> + */
> + if (net_eq(ns0, ns1))
> + return true;
> +
> + mode0 = ns0 ? vsock_net_mode(ns0) : VSOCK_NET_MODE_GLOBAL;
> + mode1 = ns1 ? vsock_net_mode(ns1) : VSOCK_NET_MODE_GLOBAL;
> +
> + /* Different namespaces are only reachable if they are both
> + * global mode.
> + */
> + return mode0 == VSOCK_NET_MODE_GLOBAL && mode0 == mode1;
> +}
> #endif /* __AF_VSOCK_H__ */
> diff --git a/include/net/net_namespace.h b/include/net/net_namespace.h
> index cb664f6e3558..66d3de1d935f 100644
> --- a/include/net/net_namespace.h
> +++ b/include/net/net_namespace.h
> @@ -37,6 +37,7 @@
> #include <net/netns/smc.h>
> #include <net/netns/bpf.h>
> #include <net/netns/mctp.h>
> +#include <net/netns/vsock.h>
> #include <net/net_trackers.h>
> #include <linux/ns_common.h>
> #include <linux/idr.h>
> @@ -196,6 +197,9 @@ struct net {
> /* Move to a better place when the config guard is removed. */
> struct mutex rtnl_mutex;
> #endif
> +#if IS_ENABLED(CONFIG_VSOCKETS)
> + struct netns_vsock vsock;
> +#endif
> } __randomize_layout;
>
> #include <linux/seq_file_net.h>
> diff --git a/include/net/netns/vsock.h b/include/net/netns/vsock.h
> new file mode 100644
> index 000000000000..e2325e2d6ec5
> --- /dev/null
> +++ b/include/net/netns/vsock.h
> @@ -0,0 +1,17 @@
> +/* SPDX-License-Identifier: GPL-2.0 */
> +#ifndef __NET_NET_NAMESPACE_VSOCK_H
> +#define __NET_NET_NAMESPACE_VSOCK_H
> +
> +#include <linux/types.h>
> +
> +enum vsock_net_mode {
> + VSOCK_NET_MODE_GLOBAL,
> + VSOCK_NET_MODE_LOCAL,
> +};
> +
> +struct netns_vsock {
> + struct ctl_table_header *sysctl_hdr;
> + enum vsock_net_mode mode;
> + enum vsock_net_mode child_ns_mode;
> +};
> +#endif /* __NET_NET_NAMESPACE_VSOCK_H */
> diff --git a/net/vmw_vsock/af_vsock.c b/net/vmw_vsock/af_vsock.c
> index a3505a4dcee0..9d614e4a4fa5 100644
> --- a/net/vmw_vsock/af_vsock.c
> +++ b/net/vmw_vsock/af_vsock.c
> @@ -83,6 +83,42 @@
> * TCP_ESTABLISHED - connected
> * TCP_CLOSING - disconnecting
> * TCP_LISTEN - listening
> + *
> + * - Namespaces in vsock support two different modes configured
> + * through /proc/sys/net/vsock/ns_mode. The modes are "local" and "global".
> + * Each mode defines how the namespace interacts with CIDs.
> + * /proc/sys/net/vsock/ns_mode is read-only and inherited from the
> + * parent namespace's /proc/sys/net/vsock/child_ns_mode at creation
> + * time and is immutable thereafter. The default is "global".
> + *
> + * The modes affect the allocation and accessibility of CIDs as follows:
> + *
> + * - global - access and allocation are all system-wide
> + * - all CID allocation from global namespaces draw from the same
> + * system-wide pool.
> + * - if one global namespace has already allocated some CID, another
> + * global namespace will not be able to allocate the same CID.
> + * - global mode AF_VSOCK sockets can reach any VM or socket in any
> global
> + * namespace, they are not contained to only their own namespace.
> + * - AF_VSOCK sockets in a global mode namespace cannot reach VMs or
> + * sockets in any local mode namespace.
> + * - local - access and allocation are contained within the namespace
> + * - CID allocation draws only from a private pool local only to the
> + * namespace, and does not affect the CIDs available for allocation in
> any
> + * other namespace (global or local).
> + * - VMs in a local namespace do not collide with CIDs in any other local
> + * namespace or any global namespace. For example, if a VM in a local
> mode
> + * namespace is given CID 10, then CID 10 is still available for
> + * allocation in any other namespace, but not in the same namespace.
> + * - AF_VSOCK sockets in a local mode namespace can connect only to VMs
> or
> + * other sockets within their own namespace.
> + * - sockets bound to VMADDR_CID_ANY in local namespaces will never
> resolve
> + * to any transport that is not compatible with local mode. There is no
> + * error that propagates to the user (as there is for connection
> attempts)
> + * because it is possible for some packet to reach this socket from
> + * a different transport that *does* support local mode. For
> + * example, virtio-vsock may not support local mode, but the socket
> + * may still accept a connection from vhost-vsock which does.
> */
>
> #include <linux/compat.h>
> @@ -100,20 +136,31 @@
> #include <linux/module.h>
> #include <linux/mutex.h>
> #include <linux/net.h>
> +#include <linux/proc_fs.h>
> #include <linux/poll.h>
> #include <linux/random.h>
> #include <linux/skbuff.h>
> #include <linux/smp.h>
> #include <linux/socket.h>
> #include <linux/stddef.h>
> +#include <linux/sysctl.h>
> #include <linux/unistd.h>
> #include <linux/wait.h>
> #include <linux/workqueue.h>
> #include <net/sock.h>
> #include <net/af_vsock.h>
> +#include <net/netns/vsock.h>
> #include <uapi/linux/vm_sockets.h>
> #include <uapi/asm-generic/ioctls.h>
>
> +#define VSOCK_NET_MODE_STR_GLOBAL "global"
> +#define VSOCK_NET_MODE_STR_LOCAL "local"
> +
> +/* 6 chars for "global", 1 for null-terminator, and 1 more for '\n'.
> + * The newline is added by proc_dostring() for read operations.
> + */
> +#define VSOCK_NET_MODE_STR_MAX 8
> +
> static int __vsock_bind(struct sock *sk, struct sockaddr_vm *addr);
> static void vsock_sk_destruct(struct sock *sk);
> static int vsock_queue_rcv_skb(struct sock *sk, struct sk_buff *skb);
> @@ -235,33 +282,42 @@ static void __vsock_remove_connected(struct vsock_sock
> *vsk)
> sock_put(&vsk->sk);
> }
>
> -static struct sock *__vsock_find_bound_socket(struct sockaddr_vm *addr)
> +static struct sock *__vsock_find_bound_socket_net(struct sockaddr_vm *addr,
> + struct net *net)
> {
> struct vsock_sock *vsk;
>
> list_for_each_entry(vsk, vsock_bound_sockets(addr), bound_table) {
> - if (vsock_addr_equals_addr(addr, &vsk->local_addr))
> - return sk_vsock(vsk);
> + struct sock *sk = sk_vsock(vsk);
> +
> + if (vsock_addr_equals_addr(addr, &vsk->local_addr) &&
> + vsock_net_check_mode(sock_net(sk), net))
> + return sk;
>
> if (addr->svm_port == vsk->local_addr.svm_port &&
> (vsk->local_addr.svm_cid == VMADDR_CID_ANY ||
> - addr->svm_cid == VMADDR_CID_ANY))
> - return sk_vsock(vsk);
> + addr->svm_cid == VMADDR_CID_ANY) &&
> + vsock_net_check_mode(sock_net(sk), net))
> + return sk;
> }
>
> return NULL;
> }
>
> -static struct sock *__vsock_find_connected_socket(struct sockaddr_vm *src,
> - struct sockaddr_vm *dst)
> +static struct sock *
> +__vsock_find_connected_socket_net(struct sockaddr_vm *src,
> + struct sockaddr_vm *dst, struct net *net)
> {
> struct vsock_sock *vsk;
>
> list_for_each_entry(vsk, vsock_connected_sockets(src, dst),
> connected_table) {
> + struct sock *sk = sk_vsock(vsk);
> +
> if (vsock_addr_equals_addr(src, &vsk->remote_addr) &&
> - dst->svm_port == vsk->local_addr.svm_port) {
> - return sk_vsock(vsk);
> + dst->svm_port == vsk->local_addr.svm_port &&
> + vsock_net_check_mode(sock_net(sk), net)) {
> + return sk;
> }
> }
>
> @@ -304,12 +360,13 @@ void vsock_remove_connected(struct vsock_sock *vsk)
> }
> EXPORT_SYMBOL_GPL(vsock_remove_connected);
>
> -struct sock *vsock_find_bound_socket(struct sockaddr_vm *addr)
> +struct sock *vsock_find_bound_socket_net(struct sockaddr_vm *addr,
> + struct net *net)
> {
> struct sock *sk;
>
> spin_lock_bh(&vsock_table_lock);
> - sk = __vsock_find_bound_socket(addr);
> + sk = __vsock_find_bound_socket_net(addr, net);
> if (sk)
> sock_hold(sk);
>
> @@ -317,15 +374,22 @@ struct sock *vsock_find_bound_socket(struct sockaddr_vm
> *addr)
>
> return sk;
> }
> +EXPORT_SYMBOL_GPL(vsock_find_bound_socket_net);
> +
> +struct sock *vsock_find_bound_socket(struct sockaddr_vm *addr)
> +{
> + return vsock_find_bound_socket_net(addr, NULL);
> +}
> EXPORT_SYMBOL_GPL(vsock_find_bound_socket);
>
> -struct sock *vsock_find_connected_socket(struct sockaddr_vm *src,
> - struct sockaddr_vm *dst)
> +struct sock *vsock_find_connected_socket_net(struct sockaddr_vm *src,
> + struct sockaddr_vm *dst,
> + struct net *net)
> {
> struct sock *sk;
>
> spin_lock_bh(&vsock_table_lock);
> - sk = __vsock_find_connected_socket(src, dst);
> + sk = __vsock_find_connected_socket_net(src, dst, net);
> if (sk)
> sock_hold(sk);
>
> @@ -333,6 +397,13 @@ struct sock *vsock_find_connected_socket(struct
> sockaddr_vm *src,
>
> return sk;
> }
> +EXPORT_SYMBOL_GPL(vsock_find_connected_socket_net);
> +
> +struct sock *vsock_find_connected_socket(struct sockaddr_vm *src,
> + struct sockaddr_vm *dst)
> +{
> + return vsock_find_connected_socket_net(src, dst, NULL);
> +}
> EXPORT_SYMBOL_GPL(vsock_find_connected_socket);
>
> void vsock_remove_sock(struct vsock_sock *vsk)
> @@ -528,7 +599,7 @@ int vsock_assign_transport(struct vsock_sock *vsk, struct
> vsock_sock *psk)
>
> if (sk->sk_type == SOCK_SEQPACKET) {
> if (!new_transport->seqpacket_allow ||
> - !new_transport->seqpacket_allow(remote_cid)) {
> + !new_transport->seqpacket_allow(vsk, remote_cid)) {
> module_put(new_transport->module);
> return -ESOCKTNOSUPPORT;
> }
> @@ -676,6 +747,7 @@ static void vsock_pending_work(struct work_struct *work)
> static int __vsock_bind_connectible(struct vsock_sock *vsk,
> struct sockaddr_vm *addr)
> {
> + struct net *net = sock_net(sk_vsock(vsk));
> static u32 port;
> struct sockaddr_vm new_addr;
>
> @@ -695,7 +767,7 @@ static int __vsock_bind_connectible(struct vsock_sock
> *vsk,
>
> new_addr.svm_port = port++;
>
> - if (!__vsock_find_bound_socket(&new_addr)) {
> + if (!__vsock_find_bound_socket_net(&new_addr, net)) {
> found = true;
> break;
> }
> @@ -712,7 +784,7 @@ static int __vsock_bind_connectible(struct vsock_sock
> *vsk,
> return -EACCES;
> }
>
> - if (__vsock_find_bound_socket(&new_addr))
> + if (__vsock_find_bound_socket_net(&new_addr, net))
> return -EADDRINUSE;
> }
>
> @@ -1314,7 +1386,7 @@ static int vsock_dgram_sendmsg(struct socket *sock,
> struct msghdr *msg,
> goto out;
> }
>
> - if (!transport->dgram_allow(remote_addr->svm_cid,
> + if (!transport->dgram_allow(vsk, remote_addr->svm_cid,
> remote_addr->svm_port)) {
> err = -EINVAL;
> goto out;
> @@ -1355,7 +1427,7 @@ static int vsock_dgram_connect(struct socket *sock,
> if (err)
> goto out;
>
> - if (!vsk->transport->dgram_allow(remote_addr->svm_cid,
> + if (!vsk->transport->dgram_allow(vsk, remote_addr->svm_cid,
> remote_addr->svm_port)) {
> err = -EINVAL;
> goto out;
> @@ -1585,7 +1657,7 @@ static int vsock_connect(struct socket *sock, struct
> sockaddr_unsized *addr,
> * endpoints.
> */
> if (!transport ||
> - !transport->stream_allow(remote_addr->svm_cid,
> + !transport->stream_allow(vsk, remote_addr->svm_cid,
> remote_addr->svm_port)) {
> err = -ENETUNREACH;
> goto out;
> @@ -2662,6 +2734,183 @@ static struct miscdevice vsock_device = {
> .fops = &vsock_device_ops,
> };
>
> +static int __vsock_net_mode_string(const struct ctl_table *table, int write,
> + void *buffer, size_t *lenp, loff_t *ppos,
> + enum vsock_net_mode mode,
> + enum vsock_net_mode *new_mode)
> +{
> + char data[VSOCK_NET_MODE_STR_MAX] = {0};
> + struct ctl_table tmp;
> + int ret;
> +
> + if (!table->data || !table->maxlen || !*lenp) {
> + *lenp = 0;
> + return 0;
> + }
> +
> + tmp = *table;
> + tmp.data = data;
> +
> + if (!write) {
> + const char *p;
> +
> + switch (mode) {
> + case VSOCK_NET_MODE_GLOBAL:
> + p = VSOCK_NET_MODE_STR_GLOBAL;
> + break;
> + case VSOCK_NET_MODE_LOCAL:
> + p = VSOCK_NET_MODE_STR_LOCAL;
> + break;
> + default:
> + WARN_ONCE(true, "netns has invalid vsock mode");
> + *lenp = 0;
> + return 0;
> + }
> +
> + strscpy(data, p, sizeof(data));
> + tmp.maxlen = strlen(p);
> + }
> +
> + ret = proc_dostring(&tmp, write, buffer, lenp, ppos);
> + if (ret)
> + return ret;
> +
> + if (!write)
> + return 0;
> +
> + if (*lenp >= sizeof(data))
> + return -EINVAL;
> +
> + if (!strncmp(data, VSOCK_NET_MODE_STR_GLOBAL, sizeof(data)))
> + *new_mode = VSOCK_NET_MODE_GLOBAL;
> + else if (!strncmp(data, VSOCK_NET_MODE_STR_LOCAL, sizeof(data)))
> + *new_mode = VSOCK_NET_MODE_LOCAL;
> + else
> + return -EINVAL;
> +
> + return 0;
> +}
> +
> +static int vsock_net_mode_string(const struct ctl_table *table, int write,
> + void *buffer, size_t *lenp, loff_t *ppos)
> +{
> + struct net *net;
> +
> + if (write)
> + return -EPERM;
> +
> + net = current->nsproxy->net_ns;
> +
> + return __vsock_net_mode_string(table, write, buffer, lenp, ppos,
> + vsock_net_mode(net), NULL);
> +}
> +
> +static int vsock_net_child_mode_string(const struct ctl_table *table, int
> write,
> + void *buffer, size_t *lenp, loff_t *ppos)
> +{
> + enum vsock_net_mode new_mode;
> + struct net *net;
> + int ret;
> +
> + net = current->nsproxy->net_ns;
> +
> + ret = __vsock_net_mode_string(table, write, buffer, lenp, ppos,
> + vsock_net_child_mode(net), &new_mode);
> + if (ret)
> + return ret;
> +
> + if (write)
> + vsock_net_set_child_mode(net, new_mode);
> +
> + return 0;
> +}
> +
> +static struct ctl_table vsock_table[] = {
> + {
> + .procname = "ns_mode",
> + .data = &init_net.vsock.mode,
> + .maxlen = VSOCK_NET_MODE_STR_MAX,
> + .mode = 0444,
> + .proc_handler = vsock_net_mode_string
> + },
> + {
> + .procname = "child_ns_mode",
> + .data = &init_net.vsock.child_ns_mode,
> + .maxlen = VSOCK_NET_MODE_STR_MAX,
> + .mode = 0644,
> + .proc_handler = vsock_net_child_mode_string
> + },
> +};
> +
> +static int __net_init vsock_sysctl_register(struct net *net)
> +{
> + struct ctl_table *table;
> +
> + if (net_eq(net, &init_net)) {
> + table = vsock_table;
> + } else {
> + table = kmemdup(vsock_table, sizeof(vsock_table), GFP_KERNEL);
> + if (!table)
> + goto err_alloc;
> +
> + table[0].data = &net->vsock.mode;
> + table[1].data = &net->vsock.child_ns_mode;
> + }
> +
> + net->vsock.sysctl_hdr = register_net_sysctl_sz(net, "net/vsock", table,
> + ARRAY_SIZE(vsock_table));
> + if (!net->vsock.sysctl_hdr)
> + goto err_reg;
> +
> + return 0;
> +
> +err_reg:
> + if (!net_eq(net, &init_net))
> + kfree(table);
> +err_alloc:
> + return -ENOMEM;
> +}
> +
> +static void vsock_sysctl_unregister(struct net *net)
> +{
> + const struct ctl_table *table;
> +
> + table = net->vsock.sysctl_hdr->ctl_table_arg;
> + unregister_net_sysctl_table(net->vsock.sysctl_hdr);
> + if (!net_eq(net, &init_net))
> + kfree(table);
> +}
> +
> +static void vsock_net_init(struct net *net)
> +{
> + if (net_eq(net, &init_net))
> + net->vsock.mode = VSOCK_NET_MODE_GLOBAL;
> + else
> + net->vsock.mode =
> vsock_net_child_mode(current->nsproxy->net_ns);
> +
> + net->vsock.child_ns_mode = VSOCK_NET_MODE_GLOBAL;
> +}
> +
> +static __net_init int vsock_sysctl_init_net(struct net *net)
> +{
> + vsock_net_init(net);
> +
> + if (vsock_sysctl_register(net))
> + return -ENOMEM;
> +
> + return 0;
> +}
> +
> +static __net_exit void vsock_sysctl_exit_net(struct net *net)
> +{
> + vsock_sysctl_unregister(net);
> +}
> +
> +static struct pernet_operations vsock_sysctl_ops __net_initdata = {
> + .init = vsock_sysctl_init_net,
> + .exit = vsock_sysctl_exit_net,
> +};
> +
> static int __init vsock_init(void)
> {
> int err = 0;
> @@ -2689,10 +2938,17 @@ static int __init vsock_init(void)
> goto err_unregister_proto;
> }
>
> + if (register_pernet_subsys(&vsock_sysctl_ops)) {
> + err = -ENOMEM;
> + goto err_unregister_sock;
> + }
> +
> vsock_bpf_build_proto();
>
> return 0;
>
> +err_unregister_sock:
> + sock_unregister(AF_VSOCK);
> err_unregister_proto:
> proto_unregister(&vsock_proto);
> err_deregister_misc:
> @@ -2706,6 +2962,7 @@ static void __exit vsock_exit(void)
> misc_deregister(&vsock_device);
> sock_unregister(AF_VSOCK);
> proto_unregister(&vsock_proto);
> + unregister_pernet_subsys(&vsock_sysctl_ops);
> }
>
> const struct vsock_transport *vsock_core_get_transport(struct vsock_sock
> *vsk)
> diff --git a/net/vmw_vsock/hyperv_transport.c
> b/net/vmw_vsock/hyperv_transport.c
> index 432fcbbd14d4..4d6d7807f152 100644
> --- a/net/vmw_vsock/hyperv_transport.c
> +++ b/net/vmw_vsock/hyperv_transport.c
> @@ -570,7 +570,7 @@ static int hvs_dgram_enqueue(struct vsock_sock *vsk,
> return -EOPNOTSUPP;
> }
>
> -static bool hvs_dgram_allow(u32 cid, u32 port)
> +static bool hvs_dgram_allow(struct vsock_sock *vsk, u32 cid, u32 port)
> {
> return false;
> }
> @@ -745,8 +745,11 @@ static bool hvs_stream_is_active(struct vsock_sock *vsk)
> return hvs->chan != NULL;
> }
>
> -static bool hvs_stream_allow(u32 cid, u32 port)
> +static bool hvs_stream_allow(struct vsock_sock *vsk, u32 cid, u32 port)
> {
> + if (vsock_net_mode(sock_net(sk_vsock(vsk))) != VSOCK_NET_MODE_GLOBAL)
> + return false;
> +
> if (cid == VMADDR_CID_HOST)
> return true;
>
> diff --git a/net/vmw_vsock/virtio_transport.c
> b/net/vmw_vsock/virtio_transport.c
> index 8c867023a2e5..37eeefddb48c 100644
> --- a/net/vmw_vsock/virtio_transport.c
> +++ b/net/vmw_vsock/virtio_transport.c
> @@ -536,7 +536,8 @@ static bool virtio_transport_msgzerocopy_allow(void)
> return true;
> }
>
> -static bool virtio_transport_seqpacket_allow(u32 remote_cid);
> +static bool virtio_transport_seqpacket_allow(struct vsock_sock *vsk,
> + u32 remote_cid);
>
> static struct virtio_transport virtio_transport = {
> .transport = {
> @@ -593,11 +594,15 @@ static struct virtio_transport virtio_transport = {
> .can_msgzerocopy = virtio_transport_can_msgzerocopy,
> };
>
> -static bool virtio_transport_seqpacket_allow(u32 remote_cid)
> +static bool
> +virtio_transport_seqpacket_allow(struct vsock_sock *vsk, u32 remote_cid)
> {
> struct virtio_vsock *vsock;
> bool seqpacket_allow;
>
> + if (vsock_net_mode(sock_net(sk_vsock(vsk))) != VSOCK_NET_MODE_GLOBAL)
> + return false;
> +
> seqpacket_allow = false;
> rcu_read_lock();
> vsock = rcu_dereference(the_virtio_vsock);
> diff --git a/net/vmw_vsock/virtio_transport_common.c
> b/net/vmw_vsock/virtio_transport_common.c
> index dcc8a1d5851e..fdb8f5b3fa60 100644
> --- a/net/vmw_vsock/virtio_transport_common.c
> +++ b/net/vmw_vsock/virtio_transport_common.c
> @@ -1043,9 +1043,9 @@ bool virtio_transport_stream_is_active(struct
> vsock_sock *vsk)
> }
> EXPORT_SYMBOL_GPL(virtio_transport_stream_is_active);
>
> -bool virtio_transport_stream_allow(u32 cid, u32 port)
> +bool virtio_transport_stream_allow(struct vsock_sock *vsk, u32 cid, u32 port)
> {
> - return true;
> + return vsock_net_mode(sock_net(sk_vsock(vsk))) == VSOCK_NET_MODE_GLOBAL;
> }
> EXPORT_SYMBOL_GPL(virtio_transport_stream_allow);
>
> @@ -1056,7 +1056,7 @@ int virtio_transport_dgram_bind(struct vsock_sock *vsk,
> }
> EXPORT_SYMBOL_GPL(virtio_transport_dgram_bind);
>
> -bool virtio_transport_dgram_allow(u32 cid, u32 port)
> +bool virtio_transport_dgram_allow(struct vsock_sock *vsk, u32 cid, u32 port)
> {
> return false;
> }
> diff --git a/net/vmw_vsock/vmci_transport.c b/net/vmw_vsock/vmci_transport.c
> index 7eccd6708d66..d5ce39ea5a1b 100644
> --- a/net/vmw_vsock/vmci_transport.c
> +++ b/net/vmw_vsock/vmci_transport.c
> @@ -646,13 +646,17 @@ static int vmci_transport_recv_dgram_cb(void *data,
> struct vmci_datagram *dg)
> return VMCI_SUCCESS;
> }
>
> -static bool vmci_transport_stream_allow(u32 cid, u32 port)
> +static bool vmci_transport_stream_allow(struct vsock_sock *vsk, u32 cid,
> + u32 port)
> {
> static const u32 non_socket_contexts[] = {
> VMADDR_CID_LOCAL,
> };
> int i;
>
> + if (vsock_net_mode(sock_net(sk_vsock(vsk))) != VSOCK_NET_MODE_GLOBAL)
> + return false;
> +
> BUILD_BUG_ON(sizeof(cid) != sizeof(*non_socket_contexts));
>
> for (i = 0; i < ARRAY_SIZE(non_socket_contexts); i++) {
> @@ -682,12 +686,10 @@ static int vmci_transport_recv_stream_cb(void *data,
> struct vmci_datagram *dg)
> err = VMCI_SUCCESS;
> bh_process_pkt = false;
>
> - /* Ignore incoming packets from contexts without sockets, or resources
> - * that aren't vsock implementations.
> + /* Ignore incoming packets from resources that aren't vsock
> + * implementations.
> */
> -
> - if (!vmci_transport_stream_allow(dg->src.context, -1)
> - || vmci_transport_peer_rid(dg->src.context) != dg->src.resource)
> + if (vmci_transport_peer_rid(dg->src.context) != dg->src.resource)
> return VMCI_ERROR_NO_ACCESS;
>
> if (VMCI_DG_SIZE(dg) < sizeof(*pkt))
> @@ -749,6 +751,12 @@ static int vmci_transport_recv_stream_cb(void *data,
> struct vmci_datagram *dg)
> goto out;
> }
>
> + /* Ignore incoming packets from contexts without sockets. */
> + if (!vmci_transport_stream_allow(vsk, dg->src.context, -1)) {
> + err = VMCI_ERROR_NO_ACCESS;
> + goto out;
> + }
> +
> /* We do most everything in a work queue, but let's fast path the
> * notification of reads and writes to help data transfer performance.
> * We can only do this if there is no process context code executing
> @@ -1784,8 +1792,12 @@ static int vmci_transport_dgram_dequeue(struct
> vsock_sock *vsk,
> return err;
> }
>
> -static bool vmci_transport_dgram_allow(u32 cid, u32 port)
> +static bool vmci_transport_dgram_allow(struct vsock_sock *vsk, u32 cid,
> + u32 port)
> {
> + if (vsock_net_mode(sock_net(sk_vsock(vsk))) != VSOCK_NET_MODE_GLOBAL)
> + return false;
> +
> if (cid == VMADDR_CID_HYPERVISOR) {
> /* Registrations of PBRPC Servers do not modify VMX/Hypervisor
> * state and are allowed.
> diff --git a/net/vmw_vsock/vsock_loopback.c b/net/vmw_vsock/vsock_loopback.c
> index bc2ff918b315..378a96dcb666 100644
> --- a/net/vmw_vsock/vsock_loopback.c
> +++ b/net/vmw_vsock/vsock_loopback.c
> @@ -46,7 +46,8 @@ static int vsock_loopback_cancel_pkt(struct vsock_sock *vsk)
> return 0;
> }
>
> -static bool vsock_loopback_seqpacket_allow(u32 remote_cid);
> +static bool vsock_loopback_seqpacket_allow(struct vsock_sock *vsk,
> + u32 remote_cid);
> static bool vsock_loopback_msgzerocopy_allow(void)
> {
> return true;
> @@ -106,9 +107,10 @@ static struct virtio_transport loopback_transport = {
> .send_pkt = vsock_loopback_send_pkt,
> };
>
> -static bool vsock_loopback_seqpacket_allow(u32 remote_cid)
> +static bool
> +vsock_loopback_seqpacket_allow(struct vsock_sock *vsk, u32 remote_cid)
> {
> - return true;
> + return vsock_net_mode(sock_net(sk_vsock(vsk))) == VSOCK_NET_MODE_GLOBAL;
> }
>
> static void vsock_loopback_work(struct work_struct *work)
>
> --
> 2.47.3
