Merge release-20200804.0-49-g343661770 (automated)

3 files changed, 27 insertions, 16 deletions

diff --git a/pkg/abi/linux/linux_abi_autogen_unsafe.go b/pkg/abi/linux/linux_abi_autogen_unsafe.go
index 0ade5d75c..8ad27da56 100644
--- a/pkg/abi/linux/linux_abi_autogen_unsafe.go
+++ b/pkg/abi/linux/linux_abi_autogen_unsafe.go
@@ -145,7 +145,7 @@ func (s *Statx) UnmarshalBytes(src []byte) {
 // Packed implements marshal.Marshallable.Packed.
 //go:nosplit
 func (s *Statx) Packed() bool {
-    return s.Mtime.Packed() && s.Atime.Packed() && s.Btime.Packed() && s.Ctime.Packed()
+    return s.Atime.Packed() && s.Btime.Packed() && s.Ctime.Packed() && s.Mtime.Packed()
 }
 
 // MarshalUnsafe implements marshal.Marshallable.MarshalUnsafe.
@@ -160,7 +160,7 @@ func (s *Statx) MarshalUnsafe(dst []byte) {
 
 // UnmarshalUnsafe implements marshal.Marshallable.UnmarshalUnsafe.
 func (s *Statx) UnmarshalUnsafe(src []byte) {
-    if s.Atime.Packed() && s.Btime.Packed() && s.Ctime.Packed() && s.Mtime.Packed() {
+    if s.Mtime.Packed() && s.Atime.Packed() && s.Btime.Packed() && s.Ctime.Packed() {
         safecopy.CopyOut(unsafe.Pointer(s), src)
     } else {
         // Type Statx doesn't have a packed layout in memory, fallback to UnmarshalBytes.
@@ -171,7 +171,7 @@ 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.Atime.Packed() && s.Btime.Packed() && s.Ctime.Packed() && s.Mtime.Packed() {
+    if !s.Mtime.Packed() && s.Atime.Packed() && s.Btime.Packed() && s.Ctime.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.
@@ -635,7 +635,7 @@ func (f *FUSEHeaderIn) MarshalUnsafe(dst []byte) {
 
 // UnmarshalUnsafe implements marshal.Marshallable.UnmarshalUnsafe.
 func (f *FUSEHeaderIn) UnmarshalUnsafe(src []byte) {
-    if f.Opcode.Packed() && f.Unique.Packed() {
+    if f.Unique.Packed() && f.Opcode.Packed() {
         safecopy.CopyOut(unsafe.Pointer(f), src)
     } else {
         // Type FUSEHeaderIn doesn't have a packed layout in memory, fallback to UnmarshalBytes.
@@ -1630,7 +1630,7 @@ func (i *IPTEntry) UnmarshalBytes(src []byte) {
 // Packed implements marshal.Marshallable.Packed.
 //go:nosplit
 func (i *IPTEntry) Packed() bool {
-    return i.Counters.Packed() && i.IP.Packed()
+    return i.IP.Packed() && i.Counters.Packed()
 }
 
 // MarshalUnsafe implements marshal.Marshallable.MarshalUnsafe.
@@ -1818,7 +1818,7 @@ func (i *IPTIP) UnmarshalBytes(src []byte) {
 // Packed implements marshal.Marshallable.Packed.
 //go:nosplit
 func (i *IPTIP) Packed() bool {
-    return i.SrcMask.Packed() && i.DstMask.Packed() && i.Src.Packed() && i.Dst.Packed()
+    return i.Dst.Packed() && i.SrcMask.Packed() && i.DstMask.Packed() && i.Src.Packed()
 }
 
 // MarshalUnsafe implements marshal.Marshallable.MarshalUnsafe.
@@ -1833,7 +1833,7 @@ func (i *IPTIP) MarshalUnsafe(dst []byte) {
 
 // UnmarshalUnsafe implements marshal.Marshallable.UnmarshalUnsafe.
 func (i *IPTIP) UnmarshalUnsafe(src []byte) {
-    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() {
         safecopy.CopyOut(unsafe.Pointer(i), src)
     } else {
         // Type IPTIP doesn't have a packed layout in memory, fallback to UnmarshalBytes.
@@ -1844,7 +1844,7 @@ 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.
@@ -1874,7 +1874,7 @@ 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.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 UnmarshalBytes.
         buf := task.CopyScratchBuffer(i.SizeBytes()) // escapes: okay.
         length, err := task.CopyInBytes(addr, buf) // escapes: okay.
@@ -1900,7 +1900,7 @@ func (i *IPTIP) CopyIn(task marshal.Task, addr usermem.Addr) (int, error) {
 
 // WriteTo implements io.WriterTo.WriteTo.
 func (i *IPTIP) WriteTo(w 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)
diff --git a/pkg/sentry/fsimpl/gofer/gofer.go b/pkg/sentry/fsimpl/gofer/gofer.go
index 4ac8dd81d..63e589859 100644
--- a/pkg/sentry/fsimpl/gofer/gofer.go
+++ b/pkg/sentry/fsimpl/gofer/gofer.go
@@ -1158,7 +1158,8 @@ func (d *dentry) OnZeroWatches(ctx context.Context) {
 // operation. One of the calls may destroy the dentry, so subsequent calls will
 // do nothing.
 //
-// Preconditions: d.fs.renameMu must be locked for writing.
+// Preconditions: d.fs.renameMu must be locked for writing; it may be
+// temporarily unlocked.
 func (d *dentry) checkCachingLocked(ctx context.Context) {
 	// Dentries with a non-zero reference count must be retained. (The only way
 	// to obtain a reference on a dentry with zero references is via path
@@ -1238,11 +1239,13 @@ func (d *dentry) checkCachingLocked(ctx context.Context) {
 	}
 }
 
-// destroyLocked destroys the dentry. It may flushes dirty pages from cache,
-// close p9 file and remove reference on parent dentry.
+// destroyLocked destroys the dentry.
 //
-// Preconditions: d.fs.renameMu must be locked for writing. d.refs == 0. d is
-// not a child dentry.
+// Preconditions:
+// * d.fs.renameMu must be locked for writing; it may be temporarily unlocked.
+// * d.refs == 0.
+// * d.parent.children[d.name] != d, i.e. d is not reachable by path traversal
+//   from its former parent dentry.
 func (d *dentry) destroyLocked(ctx context.Context) {
 	switch atomic.LoadInt64(&d.refs) {
 	case 0:
@@ -1254,6 +1257,10 @@ func (d *dentry) destroyLocked(ctx context.Context) {
 		panic("dentry.destroyLocked() called with references on the dentry")
 	}
 
+	// Allow the following to proceed without renameMu locked to improve
+	// scalability.
+	d.fs.renameMu.Unlock()
+
 	mf := d.fs.mfp.MemoryFile()
 	d.handleMu.Lock()
 	d.dataMu.Lock()
@@ -1315,6 +1322,9 @@ func (d *dentry) destroyLocked(ctx context.Context) {
 		delete(d.fs.syncableDentries, d)
 		d.fs.syncMu.Unlock()
 	}
+
+	d.fs.renameMu.Lock()
+
 	// Drop the reference held by d on its parent without recursively locking
 	// d.fs.renameMu.
 	if d.parent != nil {
diff --git a/pkg/sentry/platform/ring0/defs_impl_arm64.go b/pkg/sentry/platform/ring0/defs_impl_arm64.go
index 9fb351879..424b66f76 100644
--- a/pkg/sentry/platform/ring0/defs_impl_arm64.go
+++ b/pkg/sentry/platform/ring0/defs_impl_arm64.go
@@ -1,9 +1,10 @@
 package ring0
 
 import (
-	"fmt"
 	"gvisor.dev/gvisor/pkg/sentry/arch"
 	"gvisor.dev/gvisor/pkg/sentry/platform/ring0/pagetables"
+
+	"fmt"
 	"gvisor.dev/gvisor/pkg/usermem"
 	"io"
 	"reflect"