Automated rollback of changelist 369686285

PiperOrigin-RevId: 371015541

1 files changed, 54 insertions, 3 deletions

diff --git a/runsc/fsgofer/fsgofer.go b/runsc/fsgofer/fsgofer.go
index e04ddda47..b81ede5ae 100644
--- a/runsc/fsgofer/fsgofer.go
+++ b/runsc/fsgofer/fsgofer.go
@@ -21,6 +21,7 @@
 package fsgofer
 
 import (
+	"errors"
 	"fmt"
 	"io"
 	"math"
@@ -58,9 +59,6 @@ var verityXattrs = map[string]struct{}{
 
 // join is equivalent to path.Join() but skips path.Clean() which is expensive.
 func join(parent, child string) string {
-	if child == "." || child == ".." {
-		panic(fmt.Sprintf("invalid child path %q", child))
-	}
 	return parent + "/" + child
 }
 
@@ -1226,3 +1224,56 @@ func (l *localFile) checkROMount() error {
 	}
 	return nil
 }
+
+func (l *localFile) MultiGetAttr(names []string) ([]p9.FullStat, error) {
+	stats := make([]p9.FullStat, 0, len(names))
+
+	if len(names) > 0 && names[0] == "" {
+		qid, valid, attr, err := l.GetAttr(p9.AttrMask{})
+		if err != nil {
+			return nil, err
+		}
+		stats = append(stats, p9.FullStat{
+			QID:   qid,
+			Valid: valid,
+			Attr:  attr,
+		})
+		names = names[1:]
+	}
+
+	parent := l.file.FD()
+	for _, name := range names {
+		child, err := unix.Openat(parent, name, openFlags|unix.O_PATH, 0)
+		if parent != l.file.FD() {
+			// Parent is no longer needed.
+			_ = unix.Close(parent)
+		}
+		if err != nil {
+			if errors.Is(err, unix.ENOENT) {
+				// No pont in continuing any further.
+				break
+			}
+			return nil, err
+		}
+
+		var stat unix.Stat_t
+		if err := unix.Fstat(child, &stat); err != nil {
+			_ = unix.Close(child)
+			return nil, err
+		}
+		valid, attr := l.fillAttr(&stat)
+		stats = append(stats, p9.FullStat{
+			QID:   l.attachPoint.makeQID(&stat),
+			Valid: valid,
+			Attr:  attr,
+		})
+		if (stat.Mode & unix.S_IFMT) != unix.S_IFDIR {
+			// Doesn't need to continue if entry is not a dir. Including symlinks
+			// that cannot be followed.
+			_ = unix.Close(child)
+			break
+		}
+		parent = child
+	}
+	return stats, nil
+}