ffv1dec: check that global parameters do not change in version 0/1

Such changes are neither allowed nor supported

Found-by: ami_stuff
Bug-Id: CVE-2013-7020
CC: libav-stable@libav.org
Signed-off-by: Anton Khirnov <anton@khirnov.net>
This commit is contained in:
Michael Niedermayer 2013-08-30 04:51:09 +02:00 committed by Anton Khirnov
parent 3187fa14a3
commit da7d839a0d

View File

@ -550,6 +550,7 @@ static int read_header(FFV1Context *f)
memset(state, 128, sizeof(state));
if (f->version < 2) {
int chroma_planes, chroma_h_shift, chroma_v_shift, transparency, colorspace, bits_per_raw_sample;
unsigned v = get_symbol(c, state, 0);
if (v > 1) {
av_log(f->avctx, AV_LOG_ERROR,
@ -566,15 +567,32 @@ static int read_header(FFV1Context *f)
get_symbol(c, state, 1) + c->one_state[i];
}
f->colorspace = get_symbol(c, state, 0); //YUV cs type
colorspace = get_symbol(c, state, 0); //YUV cs type
bits_per_raw_sample = f->version > 0 ? get_symbol(c, state, 0) : f->avctx->bits_per_raw_sample;
chroma_planes = get_rac(c, state);
chroma_h_shift = get_symbol(c, state, 0);
chroma_v_shift = get_symbol(c, state, 0);
transparency = get_rac(c, state);
if (f->version > 0)
f->avctx->bits_per_raw_sample = get_symbol(c, state, 0);
if (f->plane_count) {
if (colorspace != f->colorspace ||
bits_per_raw_sample != f->avctx->bits_per_raw_sample ||
chroma_planes != f->chroma_planes ||
chroma_h_shift != f->chroma_h_shift ||
chroma_v_shift != f->chroma_v_shift ||
transparency != f->transparency) {
av_log(f->avctx, AV_LOG_ERROR, "Invalid change of global parameters\n");
return AVERROR_INVALIDDATA;
}
}
f->colorspace = colorspace;
f->avctx->bits_per_raw_sample = bits_per_raw_sample;
f->chroma_planes = chroma_planes;
f->chroma_h_shift = chroma_h_shift;
f->chroma_v_shift = chroma_v_shift;
f->transparency = transparency;
f->chroma_planes = get_rac(c, state);
f->chroma_h_shift = get_symbol(c, state, 0);
f->chroma_v_shift = get_symbol(c, state, 0);
f->transparency = get_rac(c, state);
f->plane_count = 2 + f->transparency;
}