bcache: Fix moving_pred()

Avoid a potential null pointer deref (e.g. from check keys for cache misses) Signed-off-by: Kent Overstreet <kmo@daterainc.com>
git-mirror · Mar 18, 2014 · 10d9dcf · 10d9dcf
1 parent da415a0
commit 10d9dcf
Showing 1 changed file with 3 additions and 5 deletions.
diff --git a/drivers/md/bcache/movinggc.c b/drivers/md/bcache/movinggc.c
@@ -24,12 +24,10 @@ static bool moving_pred(struct keybuf *buf, struct bkey *k)
 					   moving_gc_keys);
 	unsigned i;
 
-	for (i = 0; i < KEY_PTRS(k); i++) {
-		struct bucket *g = PTR_BUCKET(c, k, i);
-
-		if (GC_MOVE(g))
+	for (i = 0; i < KEY_PTRS(k); i++)
+		if (ptr_available(c, k, i) &&
+		    GC_MOVE(PTR_BUCKET(c, k, i)))
 			return true;
-	}
 
 	return false;
 }