From 1b6a1780de9e8f350bfea12394bbf1d59bef4d46 Mon Sep 17 00:00:00 2001
From: Kostya Shishkov <kostya.shishkov@gmail.com>
Date: Sat, 4 Apr 2020 12:27:17 +0200
Subject: [PATCH] rv20: validate slice start

---
 nihav-realmedia/src/codecs/rv20.rs | 1 +
 1 file changed, 1 insertion(+)

diff --git a/nihav-realmedia/src/codecs/rv20.rs b/nihav-realmedia/src/codecs/rv20.rs
index 8e4965a..0e74396 100644
--- a/nihav-realmedia/src/codecs/rv20.rs
+++ b/nihav-realmedia/src/codecs/rv20.rs
@@ -353,6 +353,7 @@ impl<'a> BlockDecoder for RealVideo20BR<'a> {
         if self.slice_no < self.num_slices {
             let pos = self.br.tell();
             let shdr2 = self.read_slice_header()?;
+            validate!(shdr2.mb_pos > shdr.mb_pos);
             mb_count = shdr2.mb_pos - shdr.mb_pos;
             self.br.seek(pos as u32)?;
         } else {
-- 
2.30.2