rv10/20: Fix a buffer overread caused by losing track of the remaining buffer size.
authorAlex Converse <alex.converse@gmail.com>
Thu, 1 Mar 2012 22:07:22 +0000 (14:07 -0800)
committerReinhard Tartler <siretart@tauware.de>
Sun, 1 Apr 2012 16:33:27 +0000 (18:33 +0200)
Found-by: Mateusz "j00ru" Jurczyk and Gynvael Coldwind
CC: libav-stable@libav.org
(cherry picked from commit 2f6528537fdd88820f3a4683d5e595d7b3a62689)

Signed-off-by: Reinhard Tartler <siretart@tauware.de>
libavcodec/rv10.c

index 223500c..3ac0378 100644 (file)
@@ -653,8 +653,12 @@ static int rv10_decode_frame(AVCodecContext *avctx,
 
     if(!avctx->slice_count){
         slice_count = (*buf++) + 1;
+        buf_size--;
         slices_hdr = buf + 4;
         buf += 8 * slice_count;
+        buf_size -= 8 * slice_count;
+        if (buf_size <= 0)
+            return AVERROR_INVALIDDATA;
     }else
         slice_count = avctx->slice_count;
 
@@ -693,7 +697,7 @@ static int rv10_decode_frame(AVCodecContext *avctx,
         s->current_picture_ptr= NULL; //so we can detect if frame_end wasnt called (find some nicer solution...)
     }
 
-    return buf_size;
+    return avpkt->size;
 }
 
 AVCodec ff_rv10_decoder = {