From 2cac35086c9e103fa98960c546d5017e7363803a Mon Sep 17 00:00:00 2001
From: Michael Niedermayer <michaelni@gmx.at>
Date: Fri, 25 Jan 2013 06:11:59 +0100
Subject: [PATCH] vqavideo: check chunk sizes before reading chunks

Upstream-Status: Backport

Commit 2cac35086c9e103fa98960c546d5017e7363803a release/0.7

Fixes out of array writes

Found-by: Mateusz "j00ru" Jurczyk and Gynvael Coldwind
Signed-off-by: Michael Niedermayer <michaelni@gmx.at>
(cherry picked from commit ab6c9332bfa1e20127a16392a0b85a4aa4840889)

Signed-off-by: Michael Niedermayer <michaelni@gmx.at>
---
 libavcodec/vqavideo.c |   10 ++++++++++
 1 files changed, 10 insertions(+), 0 deletions(-)

diff --git a/libavcodec/vqavideo.c b/libavcodec/vqavideo.c
index d1eab5b..6e1ce6c 100644
--- a/gst-libs/ext/libav/libavcodec/vqavideo.c
+++ b/gst-libs/ext/libav/libavcodec/vqavideo.c
@@ -527,6 +527,11 @@ static void vqa_decode_chunk(VqaContext *s)
         chunk_size = AV_RB32(&s->buf[cbp0_chunk + 4]);
         cbp0_chunk += CHUNK_PREAMBLE_SIZE;
 
+        if (chunk_size > MAX_CODEBOOK_SIZE - s->next_codebook_buffer_index) {
+            av_log(s->avctx, AV_LOG_ERROR, "cbp0 chunk too large (0x%X bytes)\n", chunk_size);
+            return AVERROR_INVALIDDATA;
+        }
+
         /* accumulate partial codebook */
         memcpy(&s->next_codebook_buffer[s->next_codebook_buffer_index],
             &s->buf[cbp0_chunk], chunk_size);
@@ -550,6 +555,11 @@ static void vqa_decode_chunk(VqaContext *s)
         chunk_size = AV_RB32(&s->buf[cbpz_chunk + 4]);
         cbpz_chunk += CHUNK_PREAMBLE_SIZE;
 
+        if (chunk_size > MAX_CODEBOOK_SIZE - s->next_codebook_buffer_index) {
+            av_log(s->avctx, AV_LOG_ERROR, "cbpz chunk too large (0x%X bytes)\n", chunk_size);
+            return AVERROR_INVALIDDATA;
+        }
+
         /* accumulate partial codebook */
         memcpy(&s->next_codebook_buffer[s->next_codebook_buffer_index],
             &s->buf[cbpz_chunk], chunk_size);
-- 
1.7.5.4