diff --git a/contrib/libarchive/libarchive/archive_write_set_format_gnutar.c b/contrib/libarchive/libarchive/archive_write_set_format_gnutar.c
index ec29c5c418e4..780ddb78aa27 100644
--- a/contrib/libarchive/libarchive/archive_write_set_format_gnutar.c
+++ b/contrib/libarchive/libarchive/archive_write_set_format_gnutar.c
@@ -635,7 +635,7 @@ archive_format_gnutar_header(struct archive_write *a, char h[512],
 	}
 
 	/* By truncating the mode here, we ensure it always fits. */
-	format_octal(archive_entry_mode(entry) & 07777,
+	format_octal(archive_entry_mode(entry) & 0777777,
 	    h + GNUTAR_mode_offset, GNUTAR_mode_size);
 
 	/* GNU tar supports base-256 here, so should never overflow. */