From 105a409ca011ae6a41707fc0c3c487f80aed33df Mon Sep 17 00:00:00 2001
From: Jeff Muizelaar <jmuizelaar@mozilla.com>
Date: Fri, 25 Jun 2010 15:20:18 -0400
Subject: [PATCH] Bug 570451 - Avoid adding unneeded lines to image; r=joe
 sr=vlad

---
 modules/libpr0n/decoders/png/nsPNGDecoder.cpp | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/modules/libpr0n/decoders/png/nsPNGDecoder.cpp b/modules/libpr0n/decoders/png/nsPNGDecoder.cpp
index febb5e83144d..9abb0589e6ac 100644
--- a/modules/libpr0n/decoders/png/nsPNGDecoder.cpp
+++ b/modules/libpr0n/decoders/png/nsPNGDecoder.cpp
@@ -776,6 +776,9 @@ row_callback(png_structp png_ptr, png_bytep new_row,
   if (decoder->mFrameIsHidden)
     return;
 
+  if (row_num >= decoder->mFrameRect.height)
+    return;
+
   if (new_row) {
     PRInt32 width = decoder->mFrameRect.width;
     PRUint32 iwidth = decoder->mFrameRect.width;