avcodec/cscd: Fix "CamStudio Lossless Codec 1.0" gzip files

Fixes: tickets/10241/cscd_1_0_306_306_gzip.avi

Signed-off-by: Michael Niedermayer <michael@niedermayer.cc>
This commit is contained in:
Michael Niedermayer 2023-09-10 16:27:02 +02:00
parent d2a0464fc2
commit ab7d38f970
No known key found for this signature in database
GPG Key ID: B18E8928B3948D64
1 changed files with 4 additions and 4 deletions

View File

@ -70,6 +70,9 @@ static int decode_frame(AVCodecContext *avctx, AVFrame *rframe,
int buf_size = avpkt->size;
CamStudioContext *c = avctx->priv_data;
int ret;
int bpp = avctx->bits_per_coded_sample / 8;
int bugdelta = FFALIGN(avctx->width * bpp, 4) * avctx->height
- (avctx->width & ~3) * bpp * avctx->height;
if (buf_size < 2) {
av_log(avctx, AV_LOG_ERROR, "coded frame too small\n");
@ -83,9 +86,6 @@ 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;
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;
@ -95,7 +95,7 @@ static int decode_frame(AVCodecContext *avctx, AVFrame *rframe,
case 1: { // zlib compression
#if CONFIG_ZLIB
unsigned long dlen = c->decomp_size;
if (uncompress(c->decomp_buf, &dlen, &buf[2], buf_size - 2) != Z_OK || dlen != c->decomp_size) {
if (uncompress(c->decomp_buf, &dlen, &buf[2], buf_size - 2) != Z_OK || (dlen != c->decomp_size && dlen != c->decomp_size - bugdelta)) {
av_log(avctx, AV_LOG_ERROR, "error during zlib decompression\n");
return AVERROR_INVALIDDATA;
}