[JFFS2] Fix unpoint length

Fix a couple of instances in JFFS2 where the unpoint() routine is
being called with the wrong length in cases where the point() routine
truncated a request.

Signed-off-by: Andy Lowe <alowe@mvista.com>
Signed-off-by: Nicolas Pitre <nico@cam.org>
Signed-off-by: David Woodhouse <dwmw2@infradead.org>
diff --git a/fs/jffs2/readinode.c b/fs/jffs2/readinode.c
index 8d4319c..2eae5d2 100644
--- a/fs/jffs2/readinode.c
+++ b/fs/jffs2/readinode.c
@@ -65,7 +65,7 @@
 		err = c->mtd->point(c->mtd, ofs, len, &retlen, &buffer);
 		if (!err && retlen < tn->csize) {
 			JFFS2_WARNING("MTD point returned len too short: %zu instead of %u.\n", retlen, tn->csize);
-			c->mtd->unpoint(c->mtd, buffer, ofs, len);
+			c->mtd->unpoint(c->mtd, buffer, ofs, retlen);
 		} else if (err)
 			JFFS2_WARNING("MTD point failed: error code %d.\n", err);
 		else