From: Matt Joiner <anacrolix@gmail.com>
Date: Wed, 19 Nov 2014 03:57:27 +0000 (-0600)
Subject: Log bad metadata packets instead of crashing
X-Git-Tag: v1.0.0~1502
X-Git-Url: http://www.git.stargrave.org/?a=commitdiff_plain;h=c8327a8fe2751bc65987b9698967ee8680691260;p=btrtrc.git

Log bad metadata packets instead of crashing
---

diff --git a/client.go b/client.go
index 88930fcf..9d97de93 100644
--- a/client.go
+++ b/client.go
@@ -846,7 +846,12 @@ func (cl *Client) gotMetadataExtensionMsg(payload []byte, t *torrent, c *connect
 		if t.haveInfo() {
 			break
 		}
-		t.SaveMetadataPiece(piece, payload[len(payload)-metadataPieceSize(d["total_size"], piece):])
+		begin := len(payload) - metadataPieceSize(d["total_size"], piece)
+		if begin < 0 || begin >= len(payload) {
+			log.Printf("got bad metadata piece")
+			break
+		}
+		t.SaveMetadataPiece(piece, payload[begin:])
 		if !t.HaveAllMetadataPieces() {
 			break
 		}