Merge release-20200907.0-42-g2747030ec (automated)

34 files changed, 68 insertions, 77 deletions

diff --git a/pkg/abi/linux/linux_abi_autogen_unsafe.go b/pkg/abi/linux/linux_abi_autogen_unsafe.go
index 78ecb304d..dde2731be 100644
--- a/pkg/abi/linux/linux_abi_autogen_unsafe.go
+++ b/pkg/abi/linux/linux_abi_autogen_unsafe.go
@@ -160,7 +160,7 @@ func (s *Statx) Packed() bool {
 
 // MarshalUnsafe implements marshal.Marshallable.MarshalUnsafe.
 func (s *Statx) MarshalUnsafe(dst []byte) {
-    if s.Mtime.Packed() && s.Atime.Packed() && s.Btime.Packed() && s.Ctime.Packed() {
+    if s.Ctime.Packed() && s.Mtime.Packed() && s.Atime.Packed() && s.Btime.Packed() {
         safecopy.CopyIn(dst, unsafe.Pointer(s))
     } else {
         // Type Statx doesn't have a packed layout in memory, fallback to MarshalBytes.
@@ -170,7 +170,7 @@ func (s *Statx) MarshalUnsafe(dst []byte) {
 
 // UnmarshalUnsafe implements marshal.Marshallable.UnmarshalUnsafe.
 func (s *Statx) UnmarshalUnsafe(src []byte) {
-    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() {
         safecopy.CopyOut(unsafe.Pointer(s), src)
     } else {
         // Type Statx doesn't have a packed layout in memory, fallback to UnmarshalBytes.
@@ -211,7 +211,7 @@ 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.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 UnmarshalBytes.
         buf := task.CopyScratchBuffer(s.SizeBytes()) // escapes: okay.
         length, err := task.CopyInBytes(addr, buf) // escapes: okay.
@@ -237,7 +237,7 @@ func (s *Statx) CopyIn(task marshal.Task, addr usermem.Addr) (int, error) {
 
 // WriteTo implements io.WriterTo.WriteTo.
 func (s *Statx) WriteTo(writer io.Writer) (int64, 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 MarshalBytes.
         buf := make([]byte, s.SizeBytes())
         s.MarshalBytes(buf)
@@ -645,7 +645,7 @@ func (f *FUSEHeaderIn) MarshalUnsafe(dst []byte) {
 
 // UnmarshalUnsafe implements marshal.Marshallable.UnmarshalUnsafe.
 func (f *FUSEHeaderIn) UnmarshalUnsafe(src []byte) {
-    if f.Unique.Packed() && f.Opcode.Packed() {
+    if f.Opcode.Packed() && f.Unique.Packed() {
         safecopy.CopyOut(unsafe.Pointer(f), src)
     } else {
         // Type FUSEHeaderIn doesn't have a packed layout in memory, fallback to UnmarshalBytes.
@@ -2049,7 +2049,7 @@ func (i *IPTEntry) UnmarshalUnsafe(src []byte) {
 // CopyOutN implements marshal.Marshallable.CopyOutN.
 //go:nosplit
 func (i *IPTEntry) CopyOutN(task marshal.Task, addr usermem.Addr, limit int) (int, error) {
-    if !i.IP.Packed() && i.Counters.Packed() {
+    if !i.Counters.Packed() && i.IP.Packed() {
         // Type IPTEntry doesn't have a packed layout in memory, fall back to MarshalBytes.
         buf := task.CopyScratchBuffer(i.SizeBytes()) // escapes: okay.
         i.MarshalBytes(buf) // escapes: fallback.
@@ -2211,12 +2211,12 @@ func (i *IPTIP) UnmarshalBytes(src []byte) {
 // Packed implements marshal.Marshallable.Packed.
 //go:nosplit
 func (i *IPTIP) Packed() bool {
-    return i.DstMask.Packed() && i.Src.Packed() && i.Dst.Packed() && i.SrcMask.Packed()
+    return i.Dst.Packed() && i.SrcMask.Packed() && i.DstMask.Packed() && i.Src.Packed()
 }
 
 // MarshalUnsafe implements marshal.Marshallable.MarshalUnsafe.
 func (i *IPTIP) MarshalUnsafe(dst []byte) {
-    if i.Dst.Packed() && i.SrcMask.Packed() && i.DstMask.Packed() && i.Src.Packed() {
+    if i.Src.Packed() && i.Dst.Packed() && i.SrcMask.Packed() && i.DstMask.Packed() {
         safecopy.CopyIn(dst, unsafe.Pointer(i))
     } else {
         // Type IPTIP doesn't have a packed layout in memory, fallback to MarshalBytes.
@@ -2226,7 +2226,7 @@ func (i *IPTIP) MarshalUnsafe(dst []byte) {
 
 // UnmarshalUnsafe implements marshal.Marshallable.UnmarshalUnsafe.
 func (i *IPTIP) UnmarshalUnsafe(src []byte) {
-    if i.Dst.Packed() && i.SrcMask.Packed() && i.DstMask.Packed() && i.Src.Packed() {
+    if i.SrcMask.Packed() && i.DstMask.Packed() && i.Src.Packed() && i.Dst.Packed() {
         safecopy.CopyOut(unsafe.Pointer(i), src)
     } else {
         // Type IPTIP doesn't have a packed layout in memory, fallback to UnmarshalBytes.
@@ -2237,7 +2237,7 @@ func (i *IPTIP) UnmarshalUnsafe(src []byte) {
 // CopyOutN implements marshal.Marshallable.CopyOutN.
 //go:nosplit
 func (i *IPTIP) CopyOutN(task marshal.Task, addr usermem.Addr, limit int) (int, error) {
-    if !i.DstMask.Packed() && i.Src.Packed() && i.Dst.Packed() && i.SrcMask.Packed() {
+    if !i.Src.Packed() && i.Dst.Packed() && i.SrcMask.Packed() && i.DstMask.Packed() {
         // Type IPTIP doesn't have a packed layout in memory, fall back to MarshalBytes.
         buf := task.CopyScratchBuffer(i.SizeBytes()) // escapes: okay.
         i.MarshalBytes(buf) // escapes: fallback.
@@ -2267,7 +2267,7 @@ func (i *IPTIP) CopyOut(task marshal.Task, addr usermem.Addr) (int, error) {
 // CopyIn implements marshal.Marshallable.CopyIn.
 //go:nosplit
 func (i *IPTIP) CopyIn(task marshal.Task, addr usermem.Addr) (int, error) {
-    if !i.SrcMask.Packed() && i.DstMask.Packed() && i.Src.Packed() && i.Dst.Packed() {
+    if !i.Src.Packed() && i.Dst.Packed() && i.SrcMask.Packed() && i.DstMask.Packed() {
         // Type IPTIP doesn't have a packed layout in memory, fall back to UnmarshalBytes.
         buf := task.CopyScratchBuffer(i.SizeBytes()) // escapes: okay.
         length, err := task.CopyInBytes(addr, buf) // escapes: okay.
@@ -2293,7 +2293,7 @@ func (i *IPTIP) CopyIn(task marshal.Task, addr usermem.Addr) (int, error) {
 
 // WriteTo implements io.WriterTo.WriteTo.
 func (i *IPTIP) WriteTo(writer io.Writer) (int64, error) {
-    if !i.Dst.Packed() && i.SrcMask.Packed() && i.DstMask.Packed() && i.Src.Packed() {
+    if !i.Src.Packed() && i.Dst.Packed() && i.SrcMask.Packed() && i.DstMask.Packed() {
         // Type IPTIP doesn't have a packed layout in memory, fall back to MarshalBytes.
         buf := make([]byte, i.SizeBytes())
         i.MarshalBytes(buf)
@@ -3058,7 +3058,7 @@ func (i *IP6TEntry) CopyOut(task marshal.Task, addr usermem.Addr) (int, error) {
 // CopyIn implements marshal.Marshallable.CopyIn.
 //go:nosplit
 func (i *IP6TEntry) CopyIn(task marshal.Task, addr usermem.Addr) (int, error) {
-    if !i.IPv6.Packed() && i.Counters.Packed() {
+    if !i.Counters.Packed() && i.IPv6.Packed() {
         // Type IP6TEntry doesn't have a packed layout in memory, fall back to UnmarshalBytes.
         buf := task.CopyScratchBuffer(i.SizeBytes()) // escapes: okay.
         length, err := task.CopyInBytes(addr, buf) // escapes: okay.
@@ -3204,7 +3204,7 @@ func (i *IP6TIP) Packed() bool {
 
 // MarshalUnsafe implements marshal.Marshallable.MarshalUnsafe.
 func (i *IP6TIP) MarshalUnsafe(dst []byte) {
-    if i.Src.Packed() && i.Dst.Packed() && i.SrcMask.Packed() && i.DstMask.Packed() {
+    if i.SrcMask.Packed() && i.DstMask.Packed() && i.Src.Packed() && i.Dst.Packed() {
         safecopy.CopyIn(dst, unsafe.Pointer(i))
     } else {
         // Type IP6TIP doesn't have a packed layout in memory, fallback to MarshalBytes.
@@ -3225,7 +3225,7 @@ func (i *IP6TIP) UnmarshalUnsafe(src []byte) {
 // CopyOutN implements marshal.Marshallable.CopyOutN.
 //go:nosplit
 func (i *IP6TIP) CopyOutN(task marshal.Task, addr usermem.Addr, limit int) (int, error) {
-    if !i.Src.Packed() && i.Dst.Packed() && i.SrcMask.Packed() && i.DstMask.Packed() {
+    if !i.DstMask.Packed() && i.Src.Packed() && i.Dst.Packed() && i.SrcMask.Packed() {
         // Type IP6TIP doesn't have a packed layout in memory, fall back to MarshalBytes.
         buf := task.CopyScratchBuffer(i.SizeBytes()) // escapes: okay.
         i.MarshalBytes(buf) // escapes: fallback.
@@ -3255,7 +3255,7 @@ func (i *IP6TIP) CopyOut(task marshal.Task, addr usermem.Addr) (int, error) {
 // CopyIn implements marshal.Marshallable.CopyIn.
 //go:nosplit
 func (i *IP6TIP) CopyIn(task marshal.Task, addr usermem.Addr) (int, error) {
-    if !i.SrcMask.Packed() && i.DstMask.Packed() && i.Src.Packed() && i.Dst.Packed() {
+    if !i.Src.Packed() && i.Dst.Packed() && i.SrcMask.Packed() && i.DstMask.Packed() {
         // Type IP6TIP doesn't have a packed layout in memory, fall back to UnmarshalBytes.
         buf := task.CopyScratchBuffer(i.SizeBytes()) // escapes: okay.
         length, err := task.CopyInBytes(addr, buf) // escapes: okay.
diff --git a/pkg/abi/linux/linux_amd64_abi_autogen_unsafe.go b/pkg/abi/linux/linux_amd64_abi_autogen_unsafe.go
index 3accfd06c..5b3acf6a5 100644
--- a/pkg/abi/linux/linux_amd64_abi_autogen_unsafe.go
+++ b/pkg/abi/linux/linux_amd64_abi_autogen_unsafe.go
@@ -293,7 +293,7 @@ func (s *Stat) Packed() bool {
 
 // MarshalUnsafe implements marshal.Marshallable.MarshalUnsafe.
 func (s *Stat) MarshalUnsafe(dst []byte) {
-    if s.ATime.Packed() && s.MTime.Packed() && s.CTime.Packed() {
+    if s.CTime.Packed() && s.ATime.Packed() && s.MTime.Packed() {
         safecopy.CopyIn(dst, unsafe.Pointer(s))
     } else {
         // Type Stat doesn't have a packed layout in memory, fallback to MarshalBytes.
@@ -314,7 +314,7 @@ func (s *Stat) UnmarshalUnsafe(src []byte) {
 // CopyOutN implements marshal.Marshallable.CopyOutN.
 //go:nosplit
 func (s *Stat) CopyOutN(task marshal.Task, addr usermem.Addr, limit int) (int, error) {
-    if !s.ATime.Packed() && s.MTime.Packed() && s.CTime.Packed() {
+    if !s.CTime.Packed() && s.ATime.Packed() && s.MTime.Packed() {
         // Type Stat doesn't have a packed layout in memory, fall back to MarshalBytes.
         buf := task.CopyScratchBuffer(s.SizeBytes()) // escapes: okay.
         s.MarshalBytes(buf) // escapes: fallback.
@@ -370,7 +370,7 @@ func (s *Stat) CopyIn(task marshal.Task, addr usermem.Addr) (int, error) {
 
 // WriteTo implements io.WriterTo.WriteTo.
 func (s *Stat) WriteTo(writer io.Writer) (int64, error) {
-    if !s.CTime.Packed() && s.ATime.Packed() && s.MTime.Packed() {
+    if !s.ATime.Packed() && s.MTime.Packed() && s.CTime.Packed() {
         // Type Stat doesn't have a packed layout in memory, fall back to MarshalBytes.
         buf := make([]byte, s.SizeBytes())
         s.MarshalBytes(buf)
diff --git a/pkg/abi/linux/linux_arm64_abi_autogen_unsafe.go b/pkg/abi/linux/linux_arm64_abi_autogen_unsafe.go
index 595e18183..3d399d1d9 100644
--- a/pkg/abi/linux/linux_arm64_abi_autogen_unsafe.go
+++ b/pkg/abi/linux/linux_arm64_abi_autogen_unsafe.go
@@ -295,12 +295,12 @@ func (s *Stat) UnmarshalBytes(src []byte) {
 // Packed implements marshal.Marshallable.Packed.
 //go:nosplit
 func (s *Stat) Packed() bool {
-    return s.MTime.Packed() && s.CTime.Packed() && s.ATime.Packed()
+    return s.ATime.Packed() && s.MTime.Packed() && s.CTime.Packed()
 }
 
 // MarshalUnsafe implements marshal.Marshallable.MarshalUnsafe.
 func (s *Stat) MarshalUnsafe(dst []byte) {
-    if s.MTime.Packed() && s.CTime.Packed() && s.ATime.Packed() {
+    if s.ATime.Packed() && s.MTime.Packed() && s.CTime.Packed() {
         safecopy.CopyIn(dst, unsafe.Pointer(s))
     } else {
         // Type Stat doesn't have a packed layout in memory, fallback to MarshalBytes.
@@ -321,7 +321,7 @@ func (s *Stat) UnmarshalUnsafe(src []byte) {
 // CopyOutN implements marshal.Marshallable.CopyOutN.
 //go:nosplit
 func (s *Stat) CopyOutN(task marshal.Task, addr usermem.Addr, limit int) (int, error) {
-    if !s.CTime.Packed() && s.ATime.Packed() && s.MTime.Packed() {
+    if !s.ATime.Packed() && s.MTime.Packed() && s.CTime.Packed() {
         // Type Stat doesn't have a packed layout in memory, fall back to MarshalBytes.
         buf := task.CopyScratchBuffer(s.SizeBytes()) // escapes: okay.
         s.MarshalBytes(buf) // escapes: fallback.
@@ -351,7 +351,7 @@ func (s *Stat) CopyOut(task marshal.Task, addr usermem.Addr) (int, error) {
 // CopyIn implements marshal.Marshallable.CopyIn.
 //go:nosplit
 func (s *Stat) CopyIn(task marshal.Task, addr usermem.Addr) (int, error) {
-    if !s.CTime.Packed() && s.ATime.Packed() && s.MTime.Packed() {
+    if !s.ATime.Packed() && s.MTime.Packed() && s.CTime.Packed() {
         // Type Stat 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/sentry/fsimpl/devpts/root_inode_refs.go b/pkg/sentry/fsimpl/devpts/root_inode_refs.go
index 051801202..1b7090229 100644
--- a/pkg/sentry/fsimpl/devpts/root_inode_refs.go
+++ b/pkg/sentry/fsimpl/devpts/root_inode_refs.go
@@ -2,11 +2,11 @@ package devpts
 
 import (
 	"fmt"
+	refs_vfs1 "gvisor.dev/gvisor/pkg/refs"
 	"runtime"
 	"sync/atomic"
 
 	"gvisor.dev/gvisor/pkg/log"
-	refs_vfs1 "gvisor.dev/gvisor/pkg/refs"
 )
 
 // ownerType is used to customize logging. Note that we use a pointer to T so
diff --git a/pkg/sentry/fsimpl/fuse/inode_refs.go b/pkg/sentry/fsimpl/fuse/inode_refs.go
index 6b9456e1d..12e7d6e6c 100644
--- a/pkg/sentry/fsimpl/fuse/inode_refs.go
+++ b/pkg/sentry/fsimpl/fuse/inode_refs.go
@@ -2,11 +2,11 @@ package fuse
 
 import (
 	"fmt"
+	refs_vfs1 "gvisor.dev/gvisor/pkg/refs"
 	"runtime"
 	"sync/atomic"
 
 	"gvisor.dev/gvisor/pkg/log"
-	refs_vfs1 "gvisor.dev/gvisor/pkg/refs"
 )
 
 // ownerType is used to customize logging. Note that we use a pointer to T so
diff --git a/pkg/sentry/fsimpl/host/connected_endpoint_refs.go b/pkg/sentry/fsimpl/host/connected_endpoint_refs.go
index babb3f664..7fa5a516d 100644
--- a/pkg/sentry/fsimpl/host/connected_endpoint_refs.go
+++ b/pkg/sentry/fsimpl/host/connected_endpoint_refs.go
@@ -2,11 +2,11 @@ package host
 
 import (
 	"fmt"
+	refs_vfs1 "gvisor.dev/gvisor/pkg/refs"
 	"runtime"
 	"sync/atomic"
 
 	"gvisor.dev/gvisor/pkg/log"
-	refs_vfs1 "gvisor.dev/gvisor/pkg/refs"
 )
 
 // ownerType is used to customize logging. Note that we use a pointer to T so
diff --git a/pkg/sentry/fsimpl/host/inode_refs.go b/pkg/sentry/fsimpl/host/inode_refs.go
index 17f90ce4a..c294b8b80 100644
--- a/pkg/sentry/fsimpl/host/inode_refs.go
+++ b/pkg/sentry/fsimpl/host/inode_refs.go
@@ -2,11 +2,11 @@ package host
 
 import (
 	"fmt"
+	refs_vfs1 "gvisor.dev/gvisor/pkg/refs"
 	"runtime"
 	"sync/atomic"
 
 	"gvisor.dev/gvisor/pkg/log"
-	refs_vfs1 "gvisor.dev/gvisor/pkg/refs"
 )
 
 // ownerType is used to customize logging. Note that we use a pointer to T so
diff --git a/pkg/sentry/fsimpl/kernfs/dentry_refs.go b/pkg/sentry/fsimpl/kernfs/dentry_refs.go
index 79863b3bc..dd5325635 100644
--- a/pkg/sentry/fsimpl/kernfs/dentry_refs.go
+++ b/pkg/sentry/fsimpl/kernfs/dentry_refs.go
@@ -2,11 +2,11 @@ package kernfs
 
 import (
 	"fmt"
+	refs_vfs1 "gvisor.dev/gvisor/pkg/refs"
 	"runtime"
 	"sync/atomic"
 
 	"gvisor.dev/gvisor/pkg/log"
-	refs_vfs1 "gvisor.dev/gvisor/pkg/refs"
 )
 
 // ownerType is used to customize logging. Note that we use a pointer to T so
diff --git a/pkg/sentry/fsimpl/kernfs/static_directory_refs.go b/pkg/sentry/fsimpl/kernfs/static_directory_refs.go
index 478b04bdd..80513f6aa 100644
--- a/pkg/sentry/fsimpl/kernfs/static_directory_refs.go
+++ b/pkg/sentry/fsimpl/kernfs/static_directory_refs.go
@@ -2,11 +2,11 @@ package kernfs
 
 import (
 	"fmt"
+	refs_vfs1 "gvisor.dev/gvisor/pkg/refs"
 	"runtime"
 	"sync/atomic"
 
 	"gvisor.dev/gvisor/pkg/log"
-	refs_vfs1 "gvisor.dev/gvisor/pkg/refs"
 )
 
 // ownerType is used to customize logging. Note that we use a pointer to T so
diff --git a/pkg/sentry/fsimpl/proc/fd_dir_inode_refs.go b/pkg/sentry/fsimpl/proc/fd_dir_inode_refs.go
index 9431c1506..8ed286c46 100644
--- a/pkg/sentry/fsimpl/proc/fd_dir_inode_refs.go
+++ b/pkg/sentry/fsimpl/proc/fd_dir_inode_refs.go
@@ -2,11 +2,11 @@ package proc
 
 import (
 	"fmt"
+	refs_vfs1 "gvisor.dev/gvisor/pkg/refs"
 	"runtime"
 	"sync/atomic"
 
 	"gvisor.dev/gvisor/pkg/log"
-	refs_vfs1 "gvisor.dev/gvisor/pkg/refs"
 )
 
 // ownerType is used to customize logging. Note that we use a pointer to T so
diff --git a/pkg/sentry/fsimpl/proc/fd_info_dir_inode_refs.go b/pkg/sentry/fsimpl/proc/fd_info_dir_inode_refs.go
index 872b20eb0..957c6a6dd 100644
--- a/pkg/sentry/fsimpl/proc/fd_info_dir_inode_refs.go
+++ b/pkg/sentry/fsimpl/proc/fd_info_dir_inode_refs.go
@@ -2,11 +2,11 @@ package proc
 
 import (
 	"fmt"
+	refs_vfs1 "gvisor.dev/gvisor/pkg/refs"
 	"runtime"
 	"sync/atomic"
 
 	"gvisor.dev/gvisor/pkg/log"
-	refs_vfs1 "gvisor.dev/gvisor/pkg/refs"
 )
 
 // ownerType is used to customize logging. Note that we use a pointer to T so
diff --git a/pkg/sentry/fsimpl/proc/subtasks_inode_refs.go b/pkg/sentry/fsimpl/proc/subtasks_inode_refs.go
index c6d9b3522..a80ec9e0a 100644
--- a/pkg/sentry/fsimpl/proc/subtasks_inode_refs.go
+++ b/pkg/sentry/fsimpl/proc/subtasks_inode_refs.go
@@ -2,11 +2,11 @@ package proc
 
 import (
 	"fmt"
+	refs_vfs1 "gvisor.dev/gvisor/pkg/refs"
 	"runtime"
 	"sync/atomic"
 
 	"gvisor.dev/gvisor/pkg/log"
-	refs_vfs1 "gvisor.dev/gvisor/pkg/refs"
 )
 
 // ownerType is used to customize logging. Note that we use a pointer to T so
diff --git a/pkg/sentry/fsimpl/proc/task_inode_refs.go b/pkg/sentry/fsimpl/proc/task_inode_refs.go
index 714488450..c4835cbca 100644
--- a/pkg/sentry/fsimpl/proc/task_inode_refs.go
+++ b/pkg/sentry/fsimpl/proc/task_inode_refs.go
@@ -2,11 +2,11 @@ package proc
 
 import (
 	"fmt"
+	refs_vfs1 "gvisor.dev/gvisor/pkg/refs"
 	"runtime"
 	"sync/atomic"
 
 	"gvisor.dev/gvisor/pkg/log"
-	refs_vfs1 "gvisor.dev/gvisor/pkg/refs"
 )
 
 // ownerType is used to customize logging. Note that we use a pointer to T so
diff --git a/pkg/sentry/fsimpl/proc/tasks_inode_refs.go b/pkg/sentry/fsimpl/proc/tasks_inode_refs.go
index 22d9cc488..5dfb34238 100644
--- a/pkg/sentry/fsimpl/proc/tasks_inode_refs.go
+++ b/pkg/sentry/fsimpl/proc/tasks_inode_refs.go
@@ -2,11 +2,11 @@ package proc
 
 import (
 	"fmt"
+	refs_vfs1 "gvisor.dev/gvisor/pkg/refs"
 	"runtime"
 	"sync/atomic"
 
 	"gvisor.dev/gvisor/pkg/log"
-	refs_vfs1 "gvisor.dev/gvisor/pkg/refs"
 )
 
 // ownerType is used to customize logging. Note that we use a pointer to T so
diff --git a/pkg/sentry/fsimpl/sys/dir_refs.go b/pkg/sentry/fsimpl/sys/dir_refs.go
index 89609b198..c05154e2b 100644
--- a/pkg/sentry/fsimpl/sys/dir_refs.go
+++ b/pkg/sentry/fsimpl/sys/dir_refs.go
@@ -2,11 +2,11 @@ package sys
 
 import (
 	"fmt"
+	refs_vfs1 "gvisor.dev/gvisor/pkg/refs"
 	"runtime"
 	"sync/atomic"
 
 	"gvisor.dev/gvisor/pkg/log"
-	refs_vfs1 "gvisor.dev/gvisor/pkg/refs"
 )
 
 // ownerType is used to customize logging. Note that we use a pointer to T so
diff --git a/pkg/sentry/fsimpl/tmpfs/inode_refs.go b/pkg/sentry/fsimpl/tmpfs/inode_refs.go
index dbf0b2766..38cc30981 100644
--- a/pkg/sentry/fsimpl/tmpfs/inode_refs.go
+++ b/pkg/sentry/fsimpl/tmpfs/inode_refs.go
@@ -2,11 +2,11 @@ package tmpfs
 
 import (
 	"fmt"
+	refs_vfs1 "gvisor.dev/gvisor/pkg/refs"
 	"runtime"
 	"sync/atomic"
 
 	"gvisor.dev/gvisor/pkg/log"
-	refs_vfs1 "gvisor.dev/gvisor/pkg/refs"
 )
 
 // ownerType is used to customize logging. Note that we use a pointer to T so
diff --git a/pkg/sentry/kernel/fd_table_refs.go b/pkg/sentry/kernel/fd_table_refs.go
index ecba138ac..8973cac8a 100644
--- a/pkg/sentry/kernel/fd_table_refs.go
+++ b/pkg/sentry/kernel/fd_table_refs.go
@@ -2,11 +2,11 @@ package kernel
 
 import (
 	"fmt"
+	refs_vfs1 "gvisor.dev/gvisor/pkg/refs"
 	"runtime"
 	"sync/atomic"
 
 	"gvisor.dev/gvisor/pkg/log"
-	refs_vfs1 "gvisor.dev/gvisor/pkg/refs"
 )
 
 // ownerType is used to customize logging. Note that we use a pointer to T so
diff --git a/pkg/sentry/kernel/fs_context_refs.go b/pkg/sentry/kernel/fs_context_refs.go
index fb2fde971..c0e01dbb3 100644
--- a/pkg/sentry/kernel/fs_context_refs.go
+++ b/pkg/sentry/kernel/fs_context_refs.go
@@ -2,11 +2,11 @@ package kernel
 
 import (
 	"fmt"
+	refs_vfs1 "gvisor.dev/gvisor/pkg/refs"
 	"runtime"
 	"sync/atomic"
 
 	"gvisor.dev/gvisor/pkg/log"
-	refs_vfs1 "gvisor.dev/gvisor/pkg/refs"
 )
 
 // ownerType is used to customize logging. Note that we use a pointer to T so
diff --git a/pkg/sentry/kernel/process_group_refs.go b/pkg/sentry/kernel/process_group_refs.go
index 4ed6e6458..5ff83ab96 100644
--- a/pkg/sentry/kernel/process_group_refs.go
+++ b/pkg/sentry/kernel/process_group_refs.go
@@ -2,11 +2,11 @@ package kernel
 
 import (
 	"fmt"
+	refs_vfs1 "gvisor.dev/gvisor/pkg/refs"
 	"runtime"
 	"sync/atomic"
 
 	"gvisor.dev/gvisor/pkg/log"
-	refs_vfs1 "gvisor.dev/gvisor/pkg/refs"
 )
 
 // ownerType is used to customize logging. Note that we use a pointer to T so
diff --git a/pkg/sentry/kernel/seqatomic_taskgoroutineschedinfo_unsafe.go b/pkg/sentry/kernel/seqatomic_taskgoroutineschedinfo_unsafe.go
index 90148bbb2..4e10436e6 100644
--- a/pkg/sentry/kernel/seqatomic_taskgoroutineschedinfo_unsafe.go
+++ b/pkg/sentry/kernel/seqatomic_taskgoroutineschedinfo_unsafe.go
@@ -1,11 +1,11 @@
 package kernel
 
 import (
-	"fmt"
 	"reflect"
 	"strings"
 	"unsafe"
 
+	"fmt"
 	"gvisor.dev/gvisor/pkg/sync"
 )
 
diff --git a/pkg/sentry/kernel/session_refs.go b/pkg/sentry/kernel/session_refs.go
index f2e1bb797..9c51eda6c 100644
--- a/pkg/sentry/kernel/session_refs.go
+++ b/pkg/sentry/kernel/session_refs.go
@@ -2,11 +2,11 @@ package kernel
 
 import (
 	"fmt"
+	refs_vfs1 "gvisor.dev/gvisor/pkg/refs"
 	"runtime"
 	"sync/atomic"
 
 	"gvisor.dev/gvisor/pkg/log"
-	refs_vfs1 "gvisor.dev/gvisor/pkg/refs"
 )
 
 // ownerType is used to customize logging. Note that we use a pointer to T so
diff --git a/pkg/sentry/kernel/shm/shm_refs.go b/pkg/sentry/kernel/shm/shm_refs.go
index 51e07d0b3..0da23fa5f 100644
--- a/pkg/sentry/kernel/shm/shm_refs.go
+++ b/pkg/sentry/kernel/shm/shm_refs.go
@@ -2,11 +2,11 @@ package shm
 
 import (
 	"fmt"
+	refs_vfs1 "gvisor.dev/gvisor/pkg/refs"
 	"runtime"
 	"sync/atomic"
 
 	"gvisor.dev/gvisor/pkg/log"
-	refs_vfs1 "gvisor.dev/gvisor/pkg/refs"
 )
 
 // ownerType is used to customize logging. Note that we use a pointer to T so
diff --git a/pkg/sentry/mm/aio_mappable_refs.go b/pkg/sentry/mm/aio_mappable_refs.go
index b99909f07..c80c56d94 100644
--- a/pkg/sentry/mm/aio_mappable_refs.go
+++ b/pkg/sentry/mm/aio_mappable_refs.go
@@ -2,11 +2,11 @@ package mm
 
 import (
 	"fmt"
+	refs_vfs1 "gvisor.dev/gvisor/pkg/refs"
 	"runtime"
 	"sync/atomic"
 
 	"gvisor.dev/gvisor/pkg/log"
-	refs_vfs1 "gvisor.dev/gvisor/pkg/refs"
 )
 
 // ownerType is used to customize logging. Note that we use a pointer to T so
diff --git a/pkg/sentry/mm/special_mappable_refs.go b/pkg/sentry/mm/special_mappable_refs.go
index 035bbe690..5eb7e69e0 100644
--- a/pkg/sentry/mm/special_mappable_refs.go
+++ b/pkg/sentry/mm/special_mappable_refs.go
@@ -2,11 +2,11 @@ package mm
 
 import (
 	"fmt"
+	refs_vfs1 "gvisor.dev/gvisor/pkg/refs"
 	"runtime"
 	"sync/atomic"
 
 	"gvisor.dev/gvisor/pkg/log"
-	refs_vfs1 "gvisor.dev/gvisor/pkg/refs"
 )
 
 // ownerType is used to customize logging. Note that we use a pointer to T so
diff --git a/pkg/sentry/platform/ring0/defs_impl_arm64.go b/pkg/sentry/platform/ring0/defs_impl_arm64.go
index 424b66f76..8ebfbfdb6 100644
--- a/pkg/sentry/platform/ring0/defs_impl_arm64.go
+++ b/pkg/sentry/platform/ring0/defs_impl_arm64.go
@@ -1,10 +1,10 @@
 package ring0
 
 import (
-	"gvisor.dev/gvisor/pkg/sentry/arch"
 	"gvisor.dev/gvisor/pkg/sentry/platform/ring0/pagetables"
 
 	"fmt"
+	"gvisor.dev/gvisor/pkg/sentry/arch"
 	"gvisor.dev/gvisor/pkg/usermem"
 	"io"
 	"reflect"
diff --git a/pkg/sentry/socket/unix/socket_refs.go b/pkg/sentry/socket/unix/socket_refs.go
index dababb85f..680ea06cd 100644
--- a/pkg/sentry/socket/unix/socket_refs.go
+++ b/pkg/sentry/socket/unix/socket_refs.go
@@ -2,11 +2,11 @@ package unix
 
 import (
 	"fmt"
+	refs_vfs1 "gvisor.dev/gvisor/pkg/refs"
 	"runtime"
 	"sync/atomic"
 
 	"gvisor.dev/gvisor/pkg/log"
-	refs_vfs1 "gvisor.dev/gvisor/pkg/refs"
 )
 
 // ownerType is used to customize logging. Note that we use a pointer to T so
diff --git a/pkg/sentry/socket/unix/transport/queue_refs.go b/pkg/sentry/socket/unix/transport/queue_refs.go
index 0d4e34988..17951eb2f 100644
--- a/pkg/sentry/socket/unix/transport/queue_refs.go
+++ b/pkg/sentry/socket/unix/transport/queue_refs.go
@@ -2,11 +2,11 @@ package transport
 
 import (
 	"fmt"
+	refs_vfs1 "gvisor.dev/gvisor/pkg/refs"
 	"runtime"
 	"sync/atomic"
 
 	"gvisor.dev/gvisor/pkg/log"
-	refs_vfs1 "gvisor.dev/gvisor/pkg/refs"
 )
 
 // ownerType is used to customize logging. Note that we use a pointer to T so
diff --git a/pkg/sentry/time/seqatomic_parameters_unsafe.go b/pkg/sentry/time/seqatomic_parameters_unsafe.go
index 2cb001080..5eb560f57 100644
--- a/pkg/sentry/time/seqatomic_parameters_unsafe.go
+++ b/pkg/sentry/time/seqatomic_parameters_unsafe.go
@@ -1,11 +1,11 @@
 package time
 
 import (
-	"fmt"
 	"reflect"
 	"strings"
 	"unsafe"
 
+	"fmt"
 	"gvisor.dev/gvisor/pkg/sync"
 )
 
diff --git a/pkg/sentry/vfs/file_description_refs.go b/pkg/sentry/vfs/file_description_refs.go
index bdd7e6554..5e612d7f0 100644
--- a/pkg/sentry/vfs/file_description_refs.go
+++ b/pkg/sentry/vfs/file_description_refs.go
@@ -2,11 +2,11 @@ package vfs
 
 import (
 	"fmt"
+	refs_vfs1 "gvisor.dev/gvisor/pkg/refs"
 	"runtime"
 	"sync/atomic"
 
 	"gvisor.dev/gvisor/pkg/log"
-	refs_vfs1 "gvisor.dev/gvisor/pkg/refs"
 )
 
 // ownerType is used to customize logging. Note that we use a pointer to T so
diff --git a/pkg/sentry/vfs/filesystem_refs.go b/pkg/sentry/vfs/filesystem_refs.go
index 38a9a986f..aaa753c43 100644
--- a/pkg/sentry/vfs/filesystem_refs.go
+++ b/pkg/sentry/vfs/filesystem_refs.go
@@ -2,11 +2,11 @@ package vfs
 
 import (
 	"fmt"
+	refs_vfs1 "gvisor.dev/gvisor/pkg/refs"
 	"runtime"
 	"sync/atomic"
 
 	"gvisor.dev/gvisor/pkg/log"
-	refs_vfs1 "gvisor.dev/gvisor/pkg/refs"
 )
 
 // ownerType is used to customize logging. Note that we use a pointer to T so
diff --git a/pkg/sentry/vfs/mount_namespace_refs.go b/pkg/sentry/vfs/mount_namespace_refs.go
index 63285fb8e..56b8d9903 100644
--- a/pkg/sentry/vfs/mount_namespace_refs.go
+++ b/pkg/sentry/vfs/mount_namespace_refs.go
@@ -2,11 +2,11 @@ package vfs
 
 import (
 	"fmt"
+	refs_vfs1 "gvisor.dev/gvisor/pkg/refs"
 	"runtime"
 	"sync/atomic"
 
 	"gvisor.dev/gvisor/pkg/log"
-	refs_vfs1 "gvisor.dev/gvisor/pkg/refs"
 )
 
 // ownerType is used to customize logging. Note that we use a pointer to T so
diff --git a/pkg/tcpip/link/tun/tun_endpoint_refs.go b/pkg/tcpip/link/tun/tun_endpoint_refs.go
index e0595429c..7f80b1fa3 100644
--- a/pkg/tcpip/link/tun/tun_endpoint_refs.go
+++ b/pkg/tcpip/link/tun/tun_endpoint_refs.go
@@ -2,11 +2,11 @@ package tun
 
 import (
 	"fmt"
+	refs_vfs1 "gvisor.dev/gvisor/pkg/refs"
 	"runtime"
 	"sync/atomic"
 
 	"gvisor.dev/gvisor/pkg/log"
-	refs_vfs1 "gvisor.dev/gvisor/pkg/refs"
 )
 
 // ownerType is used to customize logging. Note that we use a pointer to T so
diff --git a/pkg/tcpip/transport/udp/endpoint.go b/pkg/tcpip/transport/udp/endpoint.go
index 2828b2c01..b572c39db 100644
--- a/pkg/tcpip/transport/udp/endpoint.go
+++ b/pkg/tcpip/transport/udp/endpoint.go
@@ -139,7 +139,7 @@ type endpoint struct {
 
 	// multicastMemberships that need to be remvoed when the endpoint is
 	// closed. Protected by the mu mutex.
-	multicastMemberships []multicastMembership
+	multicastMemberships map[multicastMembership]struct{}
 
 	// effectiveNetProtos contains the network protocols actually in use. In
 	// most cases it will only contain "netProto", but in cases like IPv6
@@ -182,12 +182,13 @@ func newEndpoint(s *stack.Stack, netProto tcpip.NetworkProtocolNumber, waiterQue
 		// TTL=1.
 		//
 		// Linux defaults to TTL=1.
-		multicastTTL:  1,
-		multicastLoop: true,
-		rcvBufSizeMax: 32 * 1024,
-		sndBufSizeMax: 32 * 1024,
-		state:         StateInitial,
-		uniqueID:      s.UniqueID(),
+		multicastTTL:         1,
+		multicastLoop:        true,
+		rcvBufSizeMax:        32 * 1024,
+		sndBufSizeMax:        32 * 1024,
+		multicastMemberships: make(map[multicastMembership]struct{}),
+		state:                StateInitial,
+		uniqueID:             s.UniqueID(),
 	}
 
 	// Override with stack defaults.
@@ -237,10 +238,10 @@ func (e *endpoint) Close() {
 		e.boundPortFlags = ports.Flags{}
 	}
 
-	for _, mem := range e.multicastMemberships {
+	for mem := range e.multicastMemberships {
 		e.stack.LeaveGroup(e.NetProto, mem.nicID, mem.multicastAddr)
 	}
-	e.multicastMemberships = nil
+	e.multicastMemberships = make(map[multicastMembership]struct{})
 
 	// Close the receive list and drain it.
 	e.rcvMu.Lock()
@@ -752,17 +753,15 @@ func (e *endpoint) SetSockOpt(opt tcpip.SettableSocketOption) *tcpip.Error {
 		e.mu.Lock()
 		defer e.mu.Unlock()
 
-		for _, mem := range e.multicastMemberships {
-			if mem == memToInsert {
-				return tcpip.ErrPortInUse
-			}
+		if _, ok := e.multicastMemberships[memToInsert]; ok {
+			return tcpip.ErrPortInUse
 		}
 
 		if err := e.stack.JoinGroup(e.NetProto, nicID, v.MulticastAddr); err != nil {
 			return err
 		}
 
-		e.multicastMemberships = append(e.multicastMemberships, memToInsert)
+		e.multicastMemberships[memToInsert] = struct{}{}
 
 	case *tcpip.RemoveMembershipOption:
 		if !header.IsV4MulticastAddress(v.MulticastAddr) && !header.IsV6MulticastAddress(v.MulticastAddr) {
@@ -786,18 +785,11 @@ func (e *endpoint) SetSockOpt(opt tcpip.SettableSocketOption) *tcpip.Error {
 		}
 
 		memToRemove := multicastMembership{nicID: nicID, multicastAddr: v.MulticastAddr}
-		memToRemoveIndex := -1
 
 		e.mu.Lock()
 		defer e.mu.Unlock()
 
-		for i, mem := range e.multicastMemberships {
-			if mem == memToRemove {
-				memToRemoveIndex = i
-				break
-			}
-		}
-		if memToRemoveIndex == -1 {
+		if _, ok := e.multicastMemberships[memToRemove]; !ok {
 			return tcpip.ErrBadLocalAddress
 		}
 
@@ -805,8 +797,7 @@ func (e *endpoint) SetSockOpt(opt tcpip.SettableSocketOption) *tcpip.Error {
 			return err
 		}
 
-		e.multicastMemberships[memToRemoveIndex] = e.multicastMemberships[len(e.multicastMemberships)-1]
-		e.multicastMemberships = e.multicastMemberships[:len(e.multicastMemberships)-1]
+		delete(e.multicastMemberships, memToRemove)
 
 	case *tcpip.BindToDeviceOption:
 		id := tcpip.NICID(*v)
diff --git a/pkg/tcpip/transport/udp/endpoint_state.go b/pkg/tcpip/transport/udp/endpoint_state.go
index 851e6b635..858c99a45 100644
--- a/pkg/tcpip/transport/udp/endpoint_state.go
+++ b/pkg/tcpip/transport/udp/endpoint_state.go
@@ -92,7 +92,7 @@ func (e *endpoint) Resume(s *stack.Stack) {
 
 	e.stack = s
 
-	for _, m := range e.multicastMemberships {
+	for m := range e.multicastMemberships {
 		if err := e.stack.JoinGroup(e.NetProto, m.nicID, m.multicastAddr); err != nil {
 			panic(err)
 		}