[JFFS2] Fix obsoletion of metadata nodes in jffs2_add_tn_to_tree()

We should keep the mdata node with higher version number, not just the
one we happen to find latest. Doh.

Signed-off-by: David Woodhouse <dwmw2@infradead.org>
diff --git a/fs/jffs2/readinode.c b/fs/jffs2/readinode.c
index 5663e8c..12e83f6 100644
--- a/fs/jffs2/readinode.c
+++ b/fs/jffs2/readinode.c
@@ -229,9 +229,16 @@
 	   check anyway. */
 	if (!tn->fn->size) {
 		if (rii->mdata_tn) {
-			/* We had a candidate mdata node already */
-			dbg_readinode("kill old mdata with ver %d\n", rii->mdata_tn->version);
-			jffs2_kill_tn(c, rii->mdata_tn);
+			if (rii->mdata_tn->version < tn->version) {
+				/* We had a candidate mdata node already */
+				dbg_readinode("kill old mdata with ver %d\n", rii->mdata_tn->version);
+				jffs2_kill_tn(c, rii->mdata_tn);
+			} else {
+				dbg_readinode("kill new mdata with ver %d (older than existing %d\n",
+					      tn->version, rii->mdata_tn->version);
+				jffs2_kill_tn(c, tn);
+				return 0;
+			}
 		}
 		rii->mdata_tn = tn;
 		dbg_readinode("keep new mdata with ver %d\n", tn->version);