Yoann Vandoorselaere noticed an attempt to mount a JFFS2 filesystem
  read-only mounts writeable instead.

From: David Woodhouse <dwmw2@infradead.org>

  and make it fix the memory leak on failure too:
Signed-off-by: David Woodhouse <dwmw2@infradead.org>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>