make xattr EPERM non-fatal in createTarFile

junnplus · junnplus · commit 68a55fe8bdba · 2022-06-23T15:17:30.000+08:00
Signed-off-by: Ye Sijun &lt;junnplus@gmail.com&gt;
diff --git a/archive/tar.go b/archive/tar.go
@@ -120,6 +120,8 @@ const (
 	whiteoutOpaqueDir = whiteoutMetaPrefix + ".opq"
 
 	paxSchilyXattr = "SCHILY.xattr."
+
+	userXattrPrefix = "user."
 )
 
 // Apply applies a tar stream of an OCI style diff tar.
@@ -393,11 +395,19 @@ func createTarFile(ctx context.Context, path, extractDir string, hdr *tar.Header
 		if strings.HasPrefix(key, paxSchilyXattr) {
 			key = key[len(paxSchilyXattr):]
 			if err := setxattr(path, key, value); err != nil {
+				if errors.Is(err, syscall.EPERM) && strings.HasPrefix(key, userXattrPrefix) {
+					// In the user.* namespace, only regular files and directories can have extended attributes.
+					// See https://man7.org/linux/man-pages/man7/xattr.7.html for details.
+					if fi, err := os.Lstat(path); err == nil && (!fi.Mode().IsRegular() && !fi.Mode().IsDir()) {
+						log.G(ctx).WithError(err).Warnf("ignored xattr %s in archive", key)
+						continue
+					}
+				}
 				if errors.Is(err, syscall.ENOTSUP) {
 					log.G(ctx).WithError(err).Warnf("ignored xattr %s in archive", key)
 					continue
 				}
-				return err
+				return fmt.Errorf("failed to setxattr %q for key %q: %w", path, key, err)
 			}
 		}
 	}

Original file line number	Diff line number	Diff line change
`@@ -120,6 +120,8 @@ const (`
`120`	`120`	`whiteoutOpaqueDir = whiteoutMetaPrefix + ".opq"`
`121`	`121`
`122`	`122`	`paxSchilyXattr = "SCHILY.xattr."`
	`123`	`+`
	`124`	`+ userXattrPrefix = "user."`
`123`	`125`	`)`
`124`	`126`
`125`	`127`	`// Apply applies a tar stream of an OCI style diff tar.`
`@@ -393,11 +395,19 @@ func createTarFile(ctx context.Context, path, extractDir string, hdr *tar.Header`
`393`	`395`	`if strings.HasPrefix(key, paxSchilyXattr) {`
`394`	`396`	`key = key[len(paxSchilyXattr):]`
`395`	`397`	`if err := setxattr(path, key, value); err != nil {`
	`398`	`+ if errors.Is(err, syscall.EPERM) && strings.HasPrefix(key, userXattrPrefix) {`
	`399`	`+ // In the user.* namespace, only regular files and directories can have extended attributes.`
	`400`	`+ // See https://man7.org/linux/man-pages/man7/xattr.7.html for details.`
	`401`	`+ if fi, err := os.Lstat(path); err == nil && (!fi.Mode().IsRegular() && !fi.Mode().IsDir()) {`
	`402`	`+ log.G(ctx).WithError(err).Warnf("ignored xattr %s in archive", key)`
	`403`	`+ continue`
	`404`	`+ }`
	`405`	`+ }`
`396`	`406`	`if errors.Is(err, syscall.ENOTSUP) {`
`397`	`407`	`log.G(ctx).WithError(err).Warnf("ignored xattr %s in archive", key)`
`398`	`408`	`continue`
`399`	`409`	`}`
`400`		`- return err`
	`410`	`+ return fmt.Errorf("failed to setxattr %q for key %q: %w", path, key, err)`
`401`	`411`	`}`
`402`	`412`	`}`
`403`	`413`	`}`