5 files changed, 52 insertions, 5 deletions
diff --git a/pkg/abi/linux/linux_abi_autogen_unsafe.go b/pkg/abi/linux/linux_abi_autogen_unsafe.go
index d50ebe915..ac656f14c 100644
--- a/pkg/abi/linux/linux_abi_autogen_unsafe.go
+++ b/pkg/abi/linux/linux_abi_autogen_unsafe.go
@@ -148,7 +148,7 @@ func (s *Statx) UnmarshalUnsafe(src []byte) {
 // CopyOutN implements marshal.Marshallable.CopyOutN.
 //go:nosplit
 func (s *Statx) CopyOutN(task marshal.Task, addr usermem.Addr, limit int) (int, error) {
-    if !s.Mtime.Packed() && s.Atime.Packed() && s.Btime.Packed() && s.Ctime.Packed() {
+    if !s.Atime.Packed() && s.Btime.Packed() && s.Ctime.Packed() && s.Mtime.Packed() {
         // Type Statx doesn't have a packed layout in memory, fall back to MarshalBytes.
         buf := task.CopyScratchBuffer(s.SizeBytes()) // escapes: okay.
         s.MarshalBytes(buf) // escapes: fallback.
@@ -178,7 +178,7 @@ func (s *Statx) CopyOut(task marshal.Task, addr usermem.Addr) (int, error) {
 // CopyIn implements marshal.Marshallable.CopyIn.
 //go:nosplit
 func (s *Statx) CopyIn(task marshal.Task, addr usermem.Addr) (int, error) {
-    if !s.Ctime.Packed() && s.Mtime.Packed() && s.Atime.Packed() && s.Btime.Packed() {
+    if !s.Atime.Packed() && s.Btime.Packed() && s.Ctime.Packed() && s.Mtime.Packed() {
         // Type Statx doesn't have a packed layout in memory, fall back to UnmarshalBytes.
         buf := task.CopyScratchBuffer(s.SizeBytes()) // escapes: okay.
         length, err := task.CopyInBytes(addr, buf) // escapes: okay.
diff --git a/pkg/syserr/netstack.go b/pkg/syserr/netstack.go
index 8ff922c69..5ae10939d 100644
--- a/pkg/syserr/netstack.go
+++ b/pkg/syserr/netstack.go
@@ -22,7 +22,7 @@ import (
 // Mapping for tcpip.Error types.
 var (
 	ErrUnknownProtocol       = New(tcpip.ErrUnknownProtocol.String(), linux.EINVAL)
-	ErrUnknownNICID          = New(tcpip.ErrUnknownNICID.String(), linux.EINVAL)
+	ErrUnknownNICID          = New(tcpip.ErrUnknownNICID.String(), linux.ENODEV)
 	ErrUnknownDevice         = New(tcpip.ErrUnknownDevice.String(), linux.ENODEV)
 	ErrUnknownProtocolOption = New(tcpip.ErrUnknownProtocolOption.String(), linux.ENOPROTOOPT)
 	ErrDuplicateNICID        = New(tcpip.ErrDuplicateNICID.String(), linux.EEXIST)
diff --git a/pkg/tcpip/transport/packet/endpoint.go b/pkg/tcpip/transport/packet/endpoint.go
index 57b7f5c19..92b487381 100644
--- a/pkg/tcpip/transport/packet/endpoint.go
+++ b/pkg/tcpip/transport/packet/endpoint.go
@@ -79,6 +79,11 @@ type endpoint struct {
 	closed        bool
 	stats         tcpip.TransportEndpointStats `state:"nosave"`
 	bound         bool
+	boundNIC      tcpip.NICID
+
+	// lastErrorMu protects lastError.
+	lastErrorMu sync.Mutex   `state:"nosave"`
+	lastError   *tcpip.Error `state:".(string)"`
 }
 
 // NewEndpoint returns a new packet endpoint.
@@ -229,12 +234,14 @@ func (ep *endpoint) Bind(addr tcpip.FullAddress) *tcpip.Error {
 	ep.mu.Lock()
 	defer ep.mu.Unlock()
 
-	if ep.bound {
-		return tcpip.ErrAlreadyBound
+	if ep.bound && ep.boundNIC == addr.NIC {
+		// If the NIC being bound is the same then just return success.
+		return nil
 	}
 
 	// Unregister endpoint with all the nics.
 	ep.stack.UnregisterPacketEndpoint(0, ep.netProto, ep)
+	ep.bound = false
 
 	// Bind endpoint to receive packets from specific interface.
 	if err := ep.stack.RegisterPacketEndpoint(addr.NIC, ep.netProto, ep); err != nil {
@@ -242,6 +249,7 @@ func (ep *endpoint) Bind(addr tcpip.FullAddress) *tcpip.Error {
 	}
 
 	ep.bound = true
+	ep.boundNIC = addr.NIC
 
 	return nil
 }
@@ -336,8 +344,21 @@ func (ep *endpoint) SetSockOptInt(opt tcpip.SockOptInt, v int) *tcpip.Error {
 	}
 }
 
+func (ep *endpoint) takeLastError() *tcpip.Error {
+	ep.lastErrorMu.Lock()
+	defer ep.lastErrorMu.Unlock()
+
+	err := ep.lastError
+	ep.lastError = nil
+	return err
+}
+
 // GetSockOpt implements tcpip.Endpoint.GetSockOpt.
 func (ep *endpoint) GetSockOpt(opt interface{}) *tcpip.Error {
+	switch opt.(type) {
+	case tcpip.ErrorOption:
+		return ep.takeLastError()
+	}
 	return tcpip.ErrNotSupported
 }
 
diff --git a/pkg/tcpip/transport/packet/endpoint_state.go b/pkg/tcpip/transport/packet/endpoint_state.go
index 9b88f17e4..e2fa96d17 100644
--- a/pkg/tcpip/transport/packet/endpoint_state.go
+++ b/pkg/tcpip/transport/packet/endpoint_state.go
@@ -15,6 +15,7 @@
 package packet
 
 import (
+	"gvisor.dev/gvisor/pkg/tcpip"
 	"gvisor.dev/gvisor/pkg/tcpip/buffer"
 	"gvisor.dev/gvisor/pkg/tcpip/stack"
 )
@@ -70,3 +71,21 @@ func (ep *endpoint) afterLoad() {
 		panic(*err)
 	}
 }
+
+// saveLastError is invoked by stateify.
+func (ep *endpoint) saveLastError() string {
+	if ep.lastError == nil {
+		return ""
+	}
+
+	return ep.lastError.String()
+}
+
+// loadLastError is invoked by stateify.
+func (ep *endpoint) loadLastError(s string) {
+	if s == "" {
+		return
+	}
+
+	ep.lastError = tcpip.StringToError(s)
+}
diff --git a/pkg/tcpip/transport/packet/packet_state_autogen.go b/pkg/tcpip/transport/packet/packet_state_autogen.go
index 06ad0b846..b7fa1cdc9 100644
--- a/pkg/tcpip/transport/packet/packet_state_autogen.go
+++ b/pkg/tcpip/transport/packet/packet_state_autogen.go
@@ -58,6 +58,8 @@ func (x *endpoint) StateFields() []string {
 		"sndBufSizeMax",
 		"closed",
 		"bound",
+		"boundNIC",
+		"lastError",
 	}
 }
 
@@ -65,6 +67,8 @@ func (x *endpoint) StateSave(m state.Sink) {
 	x.beforeSave()
 	var rcvBufSizeMax int = x.saveRcvBufSizeMax()
 	m.SaveValue(5, rcvBufSizeMax)
+	var lastError string = x.saveLastError()
+	m.SaveValue(13, lastError)
 	m.Save(0, &x.TransportEndpointInfo)
 	m.Save(1, &x.netProto)
 	m.Save(2, &x.waiterQueue)
@@ -76,6 +80,7 @@ func (x *endpoint) StateSave(m state.Sink) {
 	m.Save(9, &x.sndBufSizeMax)
 	m.Save(10, &x.closed)
 	m.Save(11, &x.bound)
+	m.Save(12, &x.boundNIC)
 }
 
 func (x *endpoint) StateLoad(m state.Source) {
@@ -90,7 +95,9 @@ func (x *endpoint) StateLoad(m state.Source) {
 	m.Load(9, &x.sndBufSizeMax)
 	m.Load(10, &x.closed)
 	m.Load(11, &x.bound)
+	m.Load(12, &x.boundNIC)
 	m.LoadValue(5, new(int), func(y interface{}) { x.loadRcvBufSizeMax(y.(int)) })
+	m.LoadValue(13, new(string), func(y interface{}) { x.loadLastError(y.(string)) })
 	m.AfterLoad(x.afterLoad)
 }