Merge release-20210921.0-29-gb510c9846 (automated)

1 files changed, 39 insertions, 0 deletions

diff --git a/pkg/sentry/inet/atomicptr_netns_unsafe.go b/pkg/sentry/inet/atomicptr_netns_unsafe.go
new file mode 100644
index 000000000..e338ca663
--- /dev/null
+++ b/pkg/sentry/inet/atomicptr_netns_unsafe.go
@@ -0,0 +1,39 @@
+package inet
+
+import (
+	"sync/atomic"
+	"unsafe"
+)
+
+// An AtomicPtr is a pointer to a value of type Value that can be atomically
+// loaded and stored. The zero value of an AtomicPtr represents nil.
+//
+// Note that copying AtomicPtr by value performs a non-atomic read of the
+// stored pointer, which is unsafe if Store() can be called concurrently; in
+// this case, do `dst.Store(src.Load())` instead.
+//
+// +stateify savable
+type NamespaceAtomicPtr struct {
+	ptr unsafe.Pointer `state:".(*Namespace)"`
+}
+
+func (p *NamespaceAtomicPtr) savePtr() *Namespace {
+	return p.Load()
+}
+
+func (p *NamespaceAtomicPtr) loadPtr(v *Namespace) {
+	p.Store(v)
+}
+
+// Load returns the value set by the most recent Store. It returns nil if there
+// has been no previous call to Store.
+//
+//go:nosplit
+func (p *NamespaceAtomicPtr) Load() *Namespace {
+	return (*Namespace)(atomic.LoadPointer(&p.ptr))
+}
+
+// Store sets the value returned by Load to x.
+func (p *NamespaceAtomicPtr) Store(x *Namespace) {
+	atomic.StorePointer(&p.ptr, (unsafe.Pointer)(x))
+}