reader.go           | 3 +--
 storage/wrappers.go | 4 ++--

diff --git a/reader.go b/reader.go
index 5c3bccada2fb743dbfac9eab4ec2d6d3a1af9613..bdfeed04047fa2001668dea64e87353d2ee7abcc 100644
--- a/reader.go
+++ b/reader.go
@@ -193,11 +193,10 @@ 				err = *ctxErr
 				return
 			}
 		}
-		b1 := b[:avail]
 		pi := int(pos / r.t.info.PieceLength)
 		ip := r.t.info.Piece(pi)
 		po := pos % r.t.info.PieceLength
-		missinggo.LimitLen(&b1, ip.Length()-po)
+		b1 := missinggo.LimitLen(b, ip.Length()-po, avail)
 		n, err = r.t.readAt(b1, pos)
 		if n != 0 {
 			err = nil
diff --git a/storage/wrappers.go b/storage/wrappers.go
index b8ba050b5503cd1729bff7f35e9d9285ffbe6283..044a1f5aa53fd62de03e4cdeed76e14d1f4189f6 100644
--- a/storage/wrappers.go
+++ b/storage/wrappers.go
@@ -45,7 +45,7 @@ 	}
 	if off+int64(len(b)) > p.mip.Length() {
 		panic("write overflows piece")
 	}
-	missinggo.LimitLen(&b, p.mip.Length()-off)
+	b = missinggo.LimitLen(b, p.mip.Length()-off)
 	return p.PieceImpl.WriteAt(b, off)
 }
 
@@ -58,7 +58,7 @@ 	if off >= p.mip.Length() {
 		err = io.EOF
 		return
 	}
-	missinggo.LimitLen(&b, p.mip.Length()-off)
+	b = missinggo.LimitLen(b, p.mip.Length()-off)
 	if len(b) == 0 {
 		return
 	}