Merge pull request #5665 from jsternberg/clear-mode-irregular

contenthash: clear ModeIrregular before sending to archive/tar

cache/contenthash/filehash.go

@@ -41,6 +41,15 @@ func NewFileHash(path string, fi os.FileInfo) (hash.Hash, error) {
 }
 
 func NewFromStat(stat *fstypes.Stat) (hash.Hash, error) {
+	// Clear the irregular file bit if this is some kind of special
+	// file. Pre-Go 1.23 behavior would only add the irregular file
+	// bit to regular files with non-handled reparse points.
+	// Current versions of Go now apply them to directories too.
+	// archive/tar.FileInfoHeader does not handle the irregular bit.
+	if stat.Mode&uint32(os.ModeType&^os.ModeIrregular) != 0 {
+		stat.Mode &^= uint32(os.ModeIrregular)
+	}
+
 	// Clear the socket bit since archive/tar.FileInfoHeader does not handle it
 	stat.Mode &^= uint32(os.ModeSocket)