Merge release-20200810.0-74-g129018ab3 (automated)

12 files changed, 118 insertions, 95 deletions

diff --git a/pkg/sentry/fs/copy_up.go b/pkg/sentry/fs/copy_up.go
index 735452b07..ff2fe6712 100644
--- a/pkg/sentry/fs/copy_up.go
+++ b/pkg/sentry/fs/copy_up.go
@@ -107,8 +107,7 @@ func copyUp(ctx context.Context, d *Dirent) error {
 // leave the upper filesystem filled with any number of parent directories
 // but the upper filesystem will never be in an inconsistent state.
 //
-// Preconditions:
-// - d.Inode.overlay is non-nil.
+// Preconditions: d.Inode.overlay is non-nil.
 func copyUpLockedForRename(ctx context.Context, d *Dirent) error {
 	for {
 		// Did we race with another copy up or does there
@@ -183,12 +182,12 @@ func doCopyUp(ctx context.Context, d *Dirent) error {
 // Returns a generic error on failure.
 //
 // Preconditions:
-// - parent.Inode.overlay.upper must be non-nil.
-// - next.Inode.overlay.copyMu must be locked writable.
-// - next.Inode.overlay.lower must be non-nil.
-// - next.Inode.overlay.lower.StableAttr.Type must be RegularFile, Directory,
+// * parent.Inode.overlay.upper must be non-nil.
+// * next.Inode.overlay.copyMu must be locked writable.
+// * next.Inode.overlay.lower must be non-nil.
+// * next.Inode.overlay.lower.StableAttr.Type must be RegularFile, Directory,
 //   or Symlink.
-// - upper filesystem must support setting file ownership and timestamps.
+// * upper filesystem must support setting file ownership and timestamps.
 func copyUpLocked(ctx context.Context, parent *Dirent, next *Dirent) error {
 	// Extract the attributes of the file we wish to copy.
 	attrs, err := next.Inode.overlay.lower.UnstableAttr(ctx)
diff --git a/pkg/sentry/fs/dirent.go b/pkg/sentry/fs/dirent.go
index a2f751068..00c526b03 100644
--- a/pkg/sentry/fs/dirent.go
+++ b/pkg/sentry/fs/dirent.go
@@ -413,9 +413,9 @@ func (d *Dirent) descendantOf(p *Dirent) bool {
 // Inode.Lookup, otherwise walk will keep d.mu locked.
 //
 // Preconditions:
-// - renameMu must be held for reading.
-// - d.mu must be held.
-// - name must must not contain "/"s.
+// * renameMu must be held for reading.
+// * d.mu must be held.
+// * name must must not contain "/"s.
 func (d *Dirent) walk(ctx context.Context, root *Dirent, name string, walkMayUnlock bool) (*Dirent, error) {
 	if !IsDir(d.Inode.StableAttr) {
 		return nil, syscall.ENOTDIR
@@ -577,9 +577,9 @@ func (d *Dirent) Walk(ctx context.Context, root *Dirent, name string) (*Dirent,
 // exists returns true if name exists in relation to d.
 //
 // Preconditions:
-// - renameMu must be held for reading.
-// - d.mu must be held.
-// - name must must not contain "/"s.
+// * renameMu must be held for reading.
+// * d.mu must be held.
+// * name must must not contain "/"s.
 func (d *Dirent) exists(ctx context.Context, root *Dirent, name string) bool {
 	child, err := d.walk(ctx, root, name, false /* may unlock */)
 	if err != nil {
diff --git a/pkg/sentry/fs/file_operations.go b/pkg/sentry/fs/file_operations.go
index 305c0f840..6ec721022 100644
--- a/pkg/sentry/fs/file_operations.go
+++ b/pkg/sentry/fs/file_operations.go
@@ -159,8 +159,9 @@ type FileOperations interface {
 	// io provides access to the virtual memory space to which pointers in args
 	// refer.
 	//
-	// Preconditions: The AddressSpace (if any) that io refers to is activated.
-	// Must only be called from a task goroutine.
+	// Preconditions:
+	// * The AddressSpace (if any) that io refers to is activated.
+	// * Must only be called from a task goroutine.
 	Ioctl(ctx context.Context, file *File, io usermem.IO, args arch.SyscallArguments) (uintptr, error)
 }
 
diff --git a/pkg/sentry/fs/fsutil/dirty_set_impl.go b/pkg/sentry/fs/fsutil/dirty_set_impl.go
index 8d462c412..9f1463389 100644
--- a/pkg/sentry/fs/fsutil/dirty_set_impl.go
+++ b/pkg/sentry/fs/fsutil/dirty_set_impl.go
@@ -347,7 +347,9 @@ func (s *DirtySet) InsertWithoutMerging(gap DirtyGapIterator, r __generics_impor
 // and returns an iterator to the inserted segment. All existing iterators
 // (including gap, but not including the returned iterator) are invalidated.
 //
-// Preconditions: r.Start >= gap.Start(); r.End <= gap.End().
+// Preconditions:
+// * r.Start >= gap.Start().
+// * r.End <= gap.End().
 func (s *DirtySet) InsertWithoutMergingUnchecked(gap DirtyGapIterator, r __generics_imported0.MappableRange, val DirtyInfo) DirtyIterator {
 	gap = gap.node.rebalanceBeforeInsert(gap)
 	splitMaxGap := DirtytrackGaps != 0 && (gap.node.nrSegments == 0 || gap.Range().Length() == gap.node.maxGap.Get())
@@ -1101,12 +1103,10 @@ func (seg DirtyIterator) End() uint64 {
 // does not invalidate any iterators.
 //
 // Preconditions:
-//
-// - r.Length() > 0.
-//
-// - The new range must not overlap an existing one: If seg.NextSegment().Ok(),
-// then r.end <= seg.NextSegment().Start(); if seg.PrevSegment().Ok(), then
-// r.start >= seg.PrevSegment().End().
+// * r.Length() > 0.
+// * The new range must not overlap an existing one:
+//   * If seg.NextSegment().Ok(), then r.end <= seg.NextSegment().Start().
+//   * If seg.PrevSegment().Ok(), then r.start >= seg.PrevSegment().End().
 func (seg DirtyIterator) SetRangeUnchecked(r __generics_imported0.MappableRange) {
 	seg.node.keys[seg.index] = r
 }
@@ -1131,8 +1131,9 @@ func (seg DirtyIterator) SetRange(r __generics_imported0.MappableRange) {
 // SetStartUnchecked mutates the iterated segment's start. This operation does
 // not invalidate any iterators.
 //
-// Preconditions: The new start must be valid: start < seg.End(); if
-// seg.PrevSegment().Ok(), then start >= seg.PrevSegment().End().
+// Preconditions: The new start must be valid:
+// * start < seg.End()
+// * If seg.PrevSegment().Ok(), then start >= seg.PrevSegment().End().
 func (seg DirtyIterator) SetStartUnchecked(start uint64) {
 	seg.node.keys[seg.index].Start = start
 }
@@ -1154,8 +1155,9 @@ func (seg DirtyIterator) SetStart(start uint64) {
 // SetEndUnchecked mutates the iterated segment's end. This operation does not
 // invalidate any iterators.
 //
-// Preconditions: The new end must be valid: end > seg.Start(); if
-// seg.NextSegment().Ok(), then end <= seg.NextSegment().Start().
+// Preconditions: The new end must be valid:
+// * end > seg.Start().
+// * If seg.NextSegment().Ok(), then end <= seg.NextSegment().Start().
 func (seg DirtyIterator) SetEndUnchecked(end uint64) {
 	seg.node.keys[seg.index].End = end
 }
@@ -1575,9 +1577,11 @@ func (s *DirtySet) ExportSortedSlices() *DirtySegmentDataSlices {
 
 // ImportSortedSlice initializes the given set from the given slice.
 //
-// Preconditions: s must be empty. sds must represent a valid set (the segments
-// in sds must have valid lengths that do not overlap). The segments in sds
-// must be sorted in ascending key order.
+// Preconditions:
+// * s must be empty.
+// * sds must represent a valid set (the segments in sds must have valid
+//   lengths that do not overlap).
+// * The segments in sds must be sorted in ascending key order.
 func (s *DirtySet) ImportSortedSlices(sds *DirtySegmentDataSlices) error {
 	if !s.IsEmpty() {
 		return fmt.Errorf("cannot import into non-empty set %v", s)
diff --git a/pkg/sentry/fs/fsutil/file_range_set.go b/pkg/sentry/fs/fsutil/file_range_set.go
index bbafebf03..9197aeb88 100644
--- a/pkg/sentry/fs/fsutil/file_range_set.go
+++ b/pkg/sentry/fs/fsutil/file_range_set.go
@@ -70,7 +70,9 @@ func (seg FileRangeIterator) FileRange() memmap.FileRange {
 
 // FileRangeOf returns the FileRange mapped by mr.
 //
-// Preconditions: seg.Range().IsSupersetOf(mr). mr.Length() != 0.
+// Preconditions:
+// * seg.Range().IsSupersetOf(mr).
+// * mr.Length() != 0.
 func (seg FileRangeIterator) FileRangeOf(mr memmap.MappableRange) memmap.FileRange {
 	frstart := seg.Value() + (mr.Start - seg.Start())
 	return memmap.FileRange{frstart, frstart + mr.Length()}
@@ -88,8 +90,10 @@ func (seg FileRangeIterator) FileRangeOf(mr memmap.MappableRange) memmap.FileRan
 // outside of optional. It returns a non-nil error if any error occurs, even
 // if the error only affects offsets in optional, but not in required.
 //
-// Preconditions: required.Length() > 0. optional.IsSupersetOf(required).
-// required and optional must be page-aligned.
+// Preconditions:
+// * required.Length() > 0.
+// * optional.IsSupersetOf(required).
+// * required and optional must be page-aligned.
 func (frs *FileRangeSet) Fill(ctx context.Context, required, optional memmap.MappableRange, mf *pgalloc.MemoryFile, kind usage.MemoryKind, readAt func(ctx context.Context, dsts safemem.BlockSeq, offset uint64) (uint64, error)) error {
 	gap := frs.LowerBoundGap(required.Start)
 	for gap.Ok() && gap.Start() < required.End {
diff --git a/pkg/sentry/fs/fsutil/file_range_set_impl.go b/pkg/sentry/fs/fsutil/file_range_set_impl.go
index e5b6d1041..374ed79b7 100644
--- a/pkg/sentry/fs/fsutil/file_range_set_impl.go
+++ b/pkg/sentry/fs/fsutil/file_range_set_impl.go
@@ -347,7 +347,9 @@ func (s *FileRangeSet) InsertWithoutMerging(gap FileRangeGapIterator, r __generi
 // and returns an iterator to the inserted segment. All existing iterators
 // (including gap, but not including the returned iterator) are invalidated.
 //
-// Preconditions: r.Start >= gap.Start(); r.End <= gap.End().
+// Preconditions:
+// * r.Start >= gap.Start().
+// * r.End <= gap.End().
 func (s *FileRangeSet) InsertWithoutMergingUnchecked(gap FileRangeGapIterator, r __generics_imported0.MappableRange, val uint64) FileRangeIterator {
 	gap = gap.node.rebalanceBeforeInsert(gap)
 	splitMaxGap := FileRangetrackGaps != 0 && (gap.node.nrSegments == 0 || gap.Range().Length() == gap.node.maxGap.Get())
@@ -1101,12 +1103,10 @@ func (seg FileRangeIterator) End() uint64 {
 // does not invalidate any iterators.
 //
 // Preconditions:
-//
-// - r.Length() > 0.
-//
-// - The new range must not overlap an existing one: If seg.NextSegment().Ok(),
-// then r.end <= seg.NextSegment().Start(); if seg.PrevSegment().Ok(), then
-// r.start >= seg.PrevSegment().End().
+// * r.Length() > 0.
+// * The new range must not overlap an existing one:
+//   * If seg.NextSegment().Ok(), then r.end <= seg.NextSegment().Start().
+//   * If seg.PrevSegment().Ok(), then r.start >= seg.PrevSegment().End().
 func (seg FileRangeIterator) SetRangeUnchecked(r __generics_imported0.MappableRange) {
 	seg.node.keys[seg.index] = r
 }
@@ -1131,8 +1131,9 @@ func (seg FileRangeIterator) SetRange(r __generics_imported0.MappableRange) {
 // SetStartUnchecked mutates the iterated segment's start. This operation does
 // not invalidate any iterators.
 //
-// Preconditions: The new start must be valid: start < seg.End(); if
-// seg.PrevSegment().Ok(), then start >= seg.PrevSegment().End().
+// Preconditions: The new start must be valid:
+// * start < seg.End()
+// * If seg.PrevSegment().Ok(), then start >= seg.PrevSegment().End().
 func (seg FileRangeIterator) SetStartUnchecked(start uint64) {
 	seg.node.keys[seg.index].Start = start
 }
@@ -1154,8 +1155,9 @@ func (seg FileRangeIterator) SetStart(start uint64) {
 // SetEndUnchecked mutates the iterated segment's end. This operation does not
 // invalidate any iterators.
 //
-// Preconditions: The new end must be valid: end > seg.Start(); if
-// seg.NextSegment().Ok(), then end <= seg.NextSegment().Start().
+// Preconditions: The new end must be valid:
+// * end > seg.Start().
+// * If seg.NextSegment().Ok(), then end <= seg.NextSegment().Start().
 func (seg FileRangeIterator) SetEndUnchecked(end uint64) {
 	seg.node.keys[seg.index].End = end
 }
@@ -1575,9 +1577,11 @@ func (s *FileRangeSet) ExportSortedSlices() *FileRangeSegmentDataSlices {
 
 // ImportSortedSlice initializes the given set from the given slice.
 //
-// Preconditions: s must be empty. sds must represent a valid set (the segments
-// in sds must have valid lengths that do not overlap). The segments in sds
-// must be sorted in ascending key order.
+// Preconditions:
+// * s must be empty.
+// * sds must represent a valid set (the segments in sds must have valid
+//   lengths that do not overlap).
+// * The segments in sds must be sorted in ascending key order.
 func (s *FileRangeSet) ImportSortedSlices(sds *FileRangeSegmentDataSlices) error {
 	if !s.IsEmpty() {
 		return fmt.Errorf("cannot import into non-empty set %v", s)
diff --git a/pkg/sentry/fs/fsutil/frame_ref_set_impl.go b/pkg/sentry/fs/fsutil/frame_ref_set_impl.go
index e799c6b71..619246875 100644
--- a/pkg/sentry/fs/fsutil/frame_ref_set_impl.go
+++ b/pkg/sentry/fs/fsutil/frame_ref_set_impl.go
@@ -347,7 +347,9 @@ func (s *FrameRefSet) InsertWithoutMerging(gap FrameRefGapIterator, r __generics
 // and returns an iterator to the inserted segment. All existing iterators
 // (including gap, but not including the returned iterator) are invalidated.
 //
-// Preconditions: r.Start >= gap.Start(); r.End <= gap.End().
+// Preconditions:
+// * r.Start >= gap.Start().
+// * r.End <= gap.End().
 func (s *FrameRefSet) InsertWithoutMergingUnchecked(gap FrameRefGapIterator, r __generics_imported0.FileRange, val uint64) FrameRefIterator {
 	gap = gap.node.rebalanceBeforeInsert(gap)
 	splitMaxGap := FrameReftrackGaps != 0 && (gap.node.nrSegments == 0 || gap.Range().Length() == gap.node.maxGap.Get())
@@ -1101,12 +1103,10 @@ func (seg FrameRefIterator) End() uint64 {
 // does not invalidate any iterators.
 //
 // Preconditions:
-//
-// - r.Length() > 0.
-//
-// - The new range must not overlap an existing one: If seg.NextSegment().Ok(),
-// then r.end <= seg.NextSegment().Start(); if seg.PrevSegment().Ok(), then
-// r.start >= seg.PrevSegment().End().
+// * r.Length() > 0.
+// * The new range must not overlap an existing one:
+//   * If seg.NextSegment().Ok(), then r.end <= seg.NextSegment().Start().
+//   * If seg.PrevSegment().Ok(), then r.start >= seg.PrevSegment().End().
 func (seg FrameRefIterator) SetRangeUnchecked(r __generics_imported0.FileRange) {
 	seg.node.keys[seg.index] = r
 }
@@ -1131,8 +1131,9 @@ func (seg FrameRefIterator) SetRange(r __generics_imported0.FileRange) {
 // SetStartUnchecked mutates the iterated segment's start. This operation does
 // not invalidate any iterators.
 //
-// Preconditions: The new start must be valid: start < seg.End(); if
-// seg.PrevSegment().Ok(), then start >= seg.PrevSegment().End().
+// Preconditions: The new start must be valid:
+// * start < seg.End()
+// * If seg.PrevSegment().Ok(), then start >= seg.PrevSegment().End().
 func (seg FrameRefIterator) SetStartUnchecked(start uint64) {
 	seg.node.keys[seg.index].Start = start
 }
@@ -1154,8 +1155,9 @@ func (seg FrameRefIterator) SetStart(start uint64) {
 // SetEndUnchecked mutates the iterated segment's end. This operation does not
 // invalidate any iterators.
 //
-// Preconditions: The new end must be valid: end > seg.Start(); if
-// seg.NextSegment().Ok(), then end <= seg.NextSegment().Start().
+// Preconditions: The new end must be valid:
+// * end > seg.Start().
+// * If seg.NextSegment().Ok(), then end <= seg.NextSegment().Start().
 func (seg FrameRefIterator) SetEndUnchecked(end uint64) {
 	seg.node.keys[seg.index].End = end
 }
@@ -1575,9 +1577,11 @@ func (s *FrameRefSet) ExportSortedSlices() *FrameRefSegmentDataSlices {
 
 // ImportSortedSlice initializes the given set from the given slice.
 //
-// Preconditions: s must be empty. sds must represent a valid set (the segments
-// in sds must have valid lengths that do not overlap). The segments in sds
-// must be sorted in ascending key order.
+// Preconditions:
+// * s must be empty.
+// * sds must represent a valid set (the segments in sds must have valid
+//   lengths that do not overlap).
+// * The segments in sds must be sorted in ascending key order.
 func (s *FrameRefSet) ImportSortedSlices(sds *FrameRefSegmentDataSlices) error {
 	if !s.IsEmpty() {
 		return fmt.Errorf("cannot import into non-empty set %v", s)
diff --git a/pkg/sentry/fs/fsutil/host_file_mapper.go b/pkg/sentry/fs/fsutil/host_file_mapper.go
index ef0113b52..1390a9a7f 100644
--- a/pkg/sentry/fs/fsutil/host_file_mapper.go
+++ b/pkg/sentry/fs/fsutil/host_file_mapper.go
@@ -80,7 +80,9 @@ func NewHostFileMapper() *HostFileMapper {
 
 // IncRefOn increments the reference count on all offsets in mr.
 //
-// Preconditions: mr.Length() != 0. mr.Start and mr.End must be page-aligned.
+// Preconditions:
+// * mr.Length() != 0.
+// * mr.Start and mr.End must be page-aligned.
 func (f *HostFileMapper) IncRefOn(mr memmap.MappableRange) {
 	f.refsMu.Lock()
 	defer f.refsMu.Unlock()
@@ -97,7 +99,9 @@ func (f *HostFileMapper) IncRefOn(mr memmap.MappableRange) {
 
 // DecRefOn decrements the reference count on all offsets in mr.
 //
-// Preconditions: mr.Length() != 0. mr.Start and mr.End must be page-aligned.
+// Preconditions:
+// * mr.Length() != 0.
+// * mr.Start and mr.End must be page-aligned.
 func (f *HostFileMapper) DecRefOn(mr memmap.MappableRange) {
 	f.refsMu.Lock()
 	defer f.refsMu.Unlock()
@@ -204,7 +208,9 @@ func (f *HostFileMapper) UnmapAll() {
 	}
 }
 
-// Preconditions: f.mapsMu must be locked. f.mappings[chunkStart] == m.
+// Preconditions:
+// * f.mapsMu must be locked.
+// * f.mappings[chunkStart] == m.
 func (f *HostFileMapper) unmapAndRemoveLocked(chunkStart uint64, m mapping) {
 	if _, _, errno := syscall.Syscall(syscall.SYS_MUNMAP, m.addr, chunkSize, 0); errno != 0 {
 		// This leaks address space and is unexpected, but is otherwise
diff --git a/pkg/sentry/fs/fsutil/inode_cached.go b/pkg/sentry/fs/fsutil/inode_cached.go
index fe8b0b6ac..9eb6f522e 100644
--- a/pkg/sentry/fs/fsutil/inode_cached.go
+++ b/pkg/sentry/fs/fsutil/inode_cached.go
@@ -684,7 +684,9 @@ func (rw *inodeReadWriter) ReadToBlocks(dsts safemem.BlockSeq) (uint64, error) {
 // maybeGrowFile grows the file's size if data has been written past the old
 // size.
 //
-// Preconditions: rw.c.attrMu and rw.c.dataMu bust be locked.
+// Preconditions:
+// * rw.c.attrMu must be locked.
+// * rw.c.dataMu must be locked.
 func (rw *inodeReadWriter) maybeGrowFile() {
 	// If the write ends beyond the file's previous size, it causes the
 	// file to grow.
diff --git a/pkg/sentry/fs/lock/lock_set.go b/pkg/sentry/fs/lock/lock_set.go
index 5356f5791..37c216b95 100644
--- a/pkg/sentry/fs/lock/lock_set.go
+++ b/pkg/sentry/fs/lock/lock_set.go
@@ -343,7 +343,9 @@ func (s *LockSet) InsertWithoutMerging(gap LockGapIterator, r LockRange, val Loc
 // and returns an iterator to the inserted segment. All existing iterators
 // (including gap, but not including the returned iterator) are invalidated.
 //
-// Preconditions: r.Start >= gap.Start(); r.End <= gap.End().
+// Preconditions:
+// * r.Start >= gap.Start().
+// * r.End <= gap.End().
 func (s *LockSet) InsertWithoutMergingUnchecked(gap LockGapIterator, r LockRange, val Lock) LockIterator {
 	gap = gap.node.rebalanceBeforeInsert(gap)
 	splitMaxGap := LocktrackGaps != 0 && (gap.node.nrSegments == 0 || gap.Range().Length() == gap.node.maxGap.Get())
@@ -1097,12 +1099,10 @@ func (seg LockIterator) End() uint64 {
 // does not invalidate any iterators.
 //
 // Preconditions:
-//
-// - r.Length() > 0.
-//
-// - The new range must not overlap an existing one: If seg.NextSegment().Ok(),
-// then r.end <= seg.NextSegment().Start(); if seg.PrevSegment().Ok(), then
-// r.start >= seg.PrevSegment().End().
+// * r.Length() > 0.
+// * The new range must not overlap an existing one:
+//   * If seg.NextSegment().Ok(), then r.end <= seg.NextSegment().Start().
+//   * If seg.PrevSegment().Ok(), then r.start >= seg.PrevSegment().End().
 func (seg LockIterator) SetRangeUnchecked(r LockRange) {
 	seg.node.keys[seg.index] = r
 }
@@ -1127,8 +1127,9 @@ func (seg LockIterator) SetRange(r LockRange) {
 // SetStartUnchecked mutates the iterated segment's start. This operation does
 // not invalidate any iterators.
 //
-// Preconditions: The new start must be valid: start < seg.End(); if
-// seg.PrevSegment().Ok(), then start >= seg.PrevSegment().End().
+// Preconditions: The new start must be valid:
+// * start < seg.End()
+// * If seg.PrevSegment().Ok(), then start >= seg.PrevSegment().End().
 func (seg LockIterator) SetStartUnchecked(start uint64) {
 	seg.node.keys[seg.index].Start = start
 }
@@ -1150,8 +1151,9 @@ func (seg LockIterator) SetStart(start uint64) {
 // SetEndUnchecked mutates the iterated segment's end. This operation does not
 // invalidate any iterators.
 //
-// Preconditions: The new end must be valid: end > seg.Start(); if
-// seg.NextSegment().Ok(), then end <= seg.NextSegment().Start().
+// Preconditions: The new end must be valid:
+// * end > seg.Start().
+// * If seg.NextSegment().Ok(), then end <= seg.NextSegment().Start().
 func (seg LockIterator) SetEndUnchecked(end uint64) {
 	seg.node.keys[seg.index].End = end
 }
@@ -1571,9 +1573,11 @@ func (s *LockSet) ExportSortedSlices() *LockSegmentDataSlices {
 
 // ImportSortedSlice initializes the given set from the given slice.
 //
-// Preconditions: s must be empty. sds must represent a valid set (the segments
-// in sds must have valid lengths that do not overlap). The segments in sds
-// must be sorted in ascending key order.
+// Preconditions:
+// * s must be empty.
+// * sds must represent a valid set (the segments in sds must have valid
+//   lengths that do not overlap).
+// * The segments in sds must be sorted in ascending key order.
 func (s *LockSet) ImportSortedSlices(sds *LockSegmentDataSlices) error {
 	if !s.IsEmpty() {
 		return fmt.Errorf("cannot import into non-empty set %v", s)
diff --git a/pkg/sentry/fs/overlay.go b/pkg/sentry/fs/overlay.go
index 35013a21b..01a1235b8 100644
--- a/pkg/sentry/fs/overlay.go
+++ b/pkg/sentry/fs/overlay.go
@@ -86,13 +86,12 @@ func isXattrOverlay(name string) bool {
 // NewOverlayRoot produces the root of an overlay.
 //
 // Preconditions:
-//
-// - upper and lower must be non-nil.
-// - upper must not be an overlay.
-// - lower should not expose character devices, pipes, or sockets, because
+// * upper and lower must be non-nil.
+// * upper must not be an overlay.
+// * lower should not expose character devices, pipes, or sockets, because
 //   copying up these types of files is not supported.
-// - lower must not require that file objects be revalidated.
-// - lower must not have dynamic file/directory content.
+// * lower must not require that file objects be revalidated.
+// * lower must not have dynamic file/directory content.
 func NewOverlayRoot(ctx context.Context, upper *Inode, lower *Inode, flags MountSourceFlags) (*Inode, error) {
 	if !IsDir(upper.StableAttr) {
 		return nil, fmt.Errorf("upper Inode is a %v, not a directory", upper.StableAttr.Type)
@@ -117,12 +116,11 @@ func NewOverlayRoot(ctx context.Context, upper *Inode, lower *Inode, flags Mount
 // NewOverlayRootFile produces the root of an overlay that points to a file.
 //
 // Preconditions:
-//
-// - lower must be non-nil.
-// - lower should not expose character devices, pipes, or sockets, because
+// * lower must be non-nil.
+// * lower should not expose character devices, pipes, or sockets, because
 //   copying up these types of files is not supported. Neither it can be a dir.
-// - lower must not require that file objects be revalidated.
-// - lower must not have dynamic file/directory content.
+// * lower must not require that file objects be revalidated.
+// * lower must not have dynamic file/directory content.
 func NewOverlayRootFile(ctx context.Context, upperMS *MountSource, lower *Inode, flags MountSourceFlags) (*Inode, error) {
 	if !IsRegular(lower.StableAttr) {
 		return nil, fmt.Errorf("lower Inode is not a regular file")
diff --git a/pkg/sentry/fs/tty/queue.go b/pkg/sentry/fs/tty/queue.go
index ceabb9b1e..c5d7ec717 100644
--- a/pkg/sentry/fs/tty/queue.go
+++ b/pkg/sentry/fs/tty/queue.go
@@ -104,8 +104,7 @@ func (q *queue) readableSize(ctx context.Context, io usermem.IO, args arch.Sysca
 // as whether the read caused more readable data to become available (whether
 // data was pushed from the wait buffer to the read buffer).
 //
-// Preconditions:
-// * l.termiosMu must be held for reading.
+// Preconditions: l.termiosMu must be held for reading.
 func (q *queue) read(ctx context.Context, dst usermem.IOSequence, l *lineDiscipline) (int64, bool, error) {
 	q.mu.Lock()
 	defer q.mu.Unlock()
@@ -145,8 +144,7 @@ func (q *queue) read(ctx context.Context, dst usermem.IOSequence, l *lineDiscipl
 
 // write writes to q from userspace.
 //
-// Preconditions:
-// * l.termiosMu must be held for reading.
+// Preconditions: l.termiosMu must be held for reading.
 func (q *queue) write(ctx context.Context, src usermem.IOSequence, l *lineDiscipline) (int64, error) {
 	q.mu.Lock()
 	defer q.mu.Unlock()
@@ -188,8 +186,7 @@ func (q *queue) write(ctx context.Context, src usermem.IOSequence, l *lineDiscip
 
 // writeBytes writes to q from b.
 //
-// Preconditions:
-// * l.termiosMu must be held for reading.
+// Preconditions: l.termiosMu must be held for reading.
 func (q *queue) writeBytes(b []byte, l *lineDiscipline) {
 	q.mu.Lock()
 	defer q.mu.Unlock()