Port netstack, hostinet, and netlink sockets to VFS2.

All three follow the same pattern:
1. Refactor VFS1 sockets into socketOpsCommon, so that most of the methods can
   be shared with VFS2.
2. Create a FileDescriptionImpl with the corresponding socket operations,
   rewriting the few that cannot be shared with VFS1.
3. Set up a VFS2 socket provider that creates a socket by setting up a dentry
   in the global Kernel.socketMount and connecting it with a new
   FileDescription.

This mostly completes the work for porting sockets to VFS2, and many syscall
tests can be enabled as a result.
There are several networking-related syscall tests that are still not passing:
1. net gofer tests
2. socketpair gofer tests
2. sendfile tests (splice is not implemented in VFS2 yet)

Updates #1478, #1484, #1485

PiperOrigin-RevId: 309457331

1 files changed, 5 insertions, 0 deletions

diff --git a/pkg/sentry/socket/netlink/provider.go b/pkg/sentry/socket/netlink/provider.go
index b0dc70e5c..0d45e5053 100644
--- a/pkg/sentry/socket/netlink/provider.go
+++ b/pkg/sentry/socket/netlink/provider.go
@@ -67,6 +67,8 @@ func RegisterProvider(protocol int, provider Provider) {
 	protocols[protocol] = provider
 }
 
+// LINT.IfChange
+
 // socketProvider implements socket.Provider.
 type socketProvider struct {
 }
@@ -105,7 +107,10 @@ func (*socketProvider) Pair(*kernel.Task, linux.SockType, int) (*fs.File, *fs.Fi
 	return nil, nil, syserr.ErrNotSupported
 }
 
+// LINT.ThenChange(./provider_vfs2.go)
+
 // init registers the socket provider.
 func init() {
 	socket.RegisterProvider(linux.AF_NETLINK, &socketProvider{})
+	socket.RegisterProviderVFS2(linux.AF_NETLINK, &socketProviderVFS2{})
 }