From: Ben Hutchings <ben@decadent.org.uk>
Date: Sat, 4 Oct 2014 16:32:39 +0100
Subject: mount: Implement -o defaults
Bug-Debian: https://bugs.debian.org/763049
Forwarded: http://www.zytor.com/pipermail/klibc/2016-January/003887.html

This is needed to support mounting non-root filesystems in
initramfs-tools.

Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
---
--- a/usr/utils/mount_opts.c
+++ b/usr/utils/mount_opts.c
@@ -89,8 +89,13 @@ parse_mount_options(char *arg, unsigned
 				break;
 		}
 
-		if (res != 0 && s[0])
-			add_extra_option(extra, opt);
+		if (res != 0 && s[0]) {
+			if (!strcmp(opt, "defaults"))
+				rwflag &= ~(MS_RDONLY|MS_NOSUID|MS_NODEV|
+					    MS_NOEXEC|MS_SYNCHRONOUS);
+			else
+				add_extra_option(extra, opt);
+		}
 	}
 
 	return rwflag;