avcodec/cscd: Check for CamStudio Lossless Codec 1.0 behavior in end check of LZO files

Alternatively the check could be simply made more tolerant
Fixes: Ticket10227
Signed-off-by: Michael Niedermayer <michael@niedermayer.cc>

libavcodec/cscd.c

@@ -83,7 +83,10 @@ static int decode_frame(AVCodecContext *avctx, AVFrame *rframe,
     switch ((buf[0] >> 1) & 7) {
     case 0: { // lzo compression
         int outlen = c->decomp_size, inlen = buf_size - 2;
-        if (av_lzo1x_decode(c->decomp_buf, &outlen, &buf[2], &inlen) || outlen) {
+        int bpp = avctx->bits_per_coded_sample / 8;
+        int bugdelta = FFALIGN(avctx->width * bpp, 4)       * avctx->height
+                     -        (avctx->width     & ~3) * bpp * avctx->height;
+        if (av_lzo1x_decode(c->decomp_buf, &outlen, &buf[2], &inlen) || (outlen && outlen != bugdelta)) {
             av_log(avctx, AV_LOG_ERROR, "error during lzo decompression\n");
             return AVERROR_INVALIDDATA;
         }