--- linux-2.6.18/fs/jffs2/nodelist.c.orig	2006-11-18 18:27:43.530579992 -0800
+++ linux-2.6.18/fs/jffs2/nodelist.c	2006-11-18 18:28:43.089525656 -0800
@@ -57,6 +57,16 @@ void jffs2_add_fd_to_list(struct jffs2_s
 void jffs2_truncate_fragtree(struct jffs2_sb_info *c, struct rb_root *list, uint32_t size)
 {
 	struct jffs2_node_frag *frag = jffs2_lookup_node_frag(list, size);
+/*
+  DM: looks like it's legal for jffs2_lookup_node_frag to return
+  NULL but we were not checking for it (which leads to kernel oops and
+  our ultimate death when mounting jffs2 fs).
+*/
+        if( NULL == frag )
+        {
+            dbg_fragtree("Hm, jffs2_lookup_node_frag returned NULL (empty fragtree)!\n");
+            return;
+        }
 
 	dbg_fragtree("truncating fragtree to 0x%08x bytes\n", size);