On Tue, Sep 16, 2025 at 04:43:45PM -0700, Bobby Eshleman wrote:
From: Bobby Eshleman <[email protected]>
Add the per-net vsock NS mode state. This only adds the structure for
holding the mode and some of the functions for setting/getting and
checking the mode, but does not integrate the functionality yet.
Signed-off-by: Bobby Eshleman <[email protected]>
---
Changes in v6:
- add orig_net_mode to store mode at creation time which will be used to
avoid breakage when namespace changes mode during socket/VM lifespan
Changes in v5:
- use /proc/sys/net/vsock/ns_mode instead of /proc/net/vsock_ns_mode
- change from net->vsock.ns_mode to net->vsock.mode
- change vsock_net_set_mode() to vsock_net_write_mode()
- vsock_net_write_mode() returns bool for write success to avoid
need to use vsock_net_mode_can_set()
- remove vsock_net_mode_can_set()
---
MAINTAINERS | 1 +
include/net/af_vsock.h | 55 +++++++++++++++++++++++++++++++++++++++++++++
include/net/net_namespace.h | 4 ++++
include/net/netns/vsock.h | 20 +++++++++++++++++
4 files changed, 80 insertions(+)
diff --git a/MAINTAINERS b/MAINTAINERS
index 47bc35743f22..bc53c67e0926 100644
--- a/MAINTAINERS
+++ b/MAINTAINERS
@@ -26634,6 +26634,7 @@ 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/include/net/af_vsock.h b/include/net/af_vsock.h
index d40e978126e3..2857e97699de 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>
@@ -65,6 +66,7 @@ struct vsock_sock {
u32 peer_shutdown;
bool sent_request;
bool ignore_connecting_rst;
+ enum vsock_net_mode orig_net_mode;
Why `orig_` prefix?
Maybe I need to review all the series, but it's a bit confusing for now.
I guess it's related to the new behaviour to not change the mode of
already created sockets (which I like), but IMHO this variable prefix is
confusing.It seems we will have another field with the "actual_" mode,
but if it's immutable, I'd avoid that prefix.
/* Protected by lock_sock(sk) */
u64 buffer_size;
@@ -256,4 +258,57 @@ 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)
+{
+ enum vsock_net_mode ret;
+
+ spin_lock_bh(&net->vsock.lock);
+ ret = net->vsock.mode;
+ spin_unlock_bh(&net->vsock.lock);
+ return ret;
+}
+
+static inline bool vsock_net_write_mode(struct net *net, u8 mode)
+{
+ bool ret;
+
+ spin_lock_bh(&net->vsock.lock);
+
+ if (net->vsock.written) {
+ ret = false;
+ goto skip;
+ }
+
+ net->vsock.mode = mode;
+ net->vsock.written = true;
+ ret = true;
+
+skip:
+ spin_unlock_bh(&net->vsock.lock);
+ return ret;
+}
+
+/* Return true if vsock_sock passes the mode rules for a given net and
+ * orig_net_mode. Otherwise, return false.
+ *
+ * net is the current net namespace of the object being checked. orig_net_mode
+ * is the mode of net when the object was created.
`orig_net_mode` is also explained in the next paragraph, should we
remove from here?
+ *
+ * orig_net_mode is the mode of arg 'net' at the time of creation for the
+ * object being checked. For example, if searching for a vsock_sock then
+ * orig_net_mode is arg net's mode at the time the vsock_sock was created.
+ *
+ * Read more about modes in the comment header of net/vmw_vsock/af_vsock.c.
+ */
+static inline bool vsock_net_check_mode(struct vsock_sock *vsk, struct net
*net,
+ enum vsock_net_mode orig_net_mode)
+{
+ struct net *vsk_net = sock_net(sk_vsock(vsk));
+
+ if (net_eq(vsk_net, net))
+ return true;
+
+ return orig_net_mode == VSOCK_NET_MODE_GLOBAL && vsk->orig_net_mode ==
VSOCK_NET_MODE_GLOBAL;
nit: I'd rewrite in this way, just because it seems easy to read to me,
but again not strong opinion, this is fine:
return orig_net_mode == VSOCK_NET_MODE_GLOBAL &&
orig_net_mode == vsk->orig_net_mode;
+}
#endif /* __AF_VSOCK_H__ */
diff --git a/include/net/net_namespace.h b/include/net/net_namespace.h
index 025a7574b275..005c0da4fb62 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..d4593c0b8dc4
--- /dev/null
+++ b/include/net/netns/vsock.h
@@ -0,0 +1,20 @@
+/* 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 *vsock_hdr;
sysctl_header, or sysctl_hdr, or sysctl_ctl ?
I'd remove `vsock_` prefix and make more clear its used for sysctl.
+ spinlock_t lock;
+
+ /* protected by lock */
+ enum vsock_net_mode mode;
+ bool written;
I would call this `mode_set` or `mode_locked`, I mean with `mode_`
prefix to make sure we don't need to rename it when we will add new
fields in the future.
Thanks
Stefano
+};
+#endif /* __NET_NET_NAMESPACE_VSOCK_H */
--
2.47.3
