On Wed, Dec 30, 2015 at 01:00:43AM +0100, Andreas Cadhalpun wrote: > On 29.12.2015 22:27, Rostislav Pehlivanov wrote: > > oggparsetheora has the same bit of code to read the gpshift, so it would > > probably be a good idea to add it to this patch as well. > > No, oggparsetheora only reads 5 bits for gpshift. > The only thing from this patch that also applies there is the (theoretical) > issue of 1<<31 not being defined for int32_t. > > On 29.12.2015 22:32, Hendrik Leppkes wrote: > > 1U << hdr->gpshift? > > Sure. Updated patch attached. > > Best regards, > Andreas
> oggparsedaala.c | 7 ++++++-
> oggparsetheora.c | 2 +-
> 2 files changed, 7 insertions(+), 2 deletions(-)
> ced39ad8585220f35fcac769d9fa0244c5a28aed
> 0001-oggparsedaala-reject-too-large-gpshift.patch
> From 4380123388f38eb9bbd11db34b0ac82a9ec18d5a Mon Sep 17 00:00:00 2001
> From: Andreas Cadhalpun <andreas.cadhal...@googlemail.com>
> Date: Tue, 29 Dec 2015 18:32:01 +0100
> Subject: [PATCH] oggparsedaala: reject too large gpshift
>
> Also use a unsigned constant for the shift calculation, as 1 << 31 is
> undefined for int32_t. This is also fixed oggparsetheora.
>
> This fixes ubsan runtime error: shift exponent is too large for
> 32-bit type 'int'
>
> Signed-off-by: Andreas Cadhalpun <andreas.cadhal...@googlemail.com>
> ---
> libavformat/oggparsedaala.c | 7 ++++++-
> libavformat/oggparsetheora.c | 2 +-
> 2 files changed, 7 insertions(+), 2 deletions(-)
>
> diff --git a/libavformat/oggparsedaala.c b/libavformat/oggparsedaala.c
> index 24567f9..3651ca1 100644
> --- a/libavformat/oggparsedaala.c
> +++ b/libavformat/oggparsedaala.c
> @@ -123,7 +123,12 @@ static int daala_header(AVFormatContext *s, int idx)
>
> hdr->frame_duration = bytestream2_get_ne32(&gb);
> hdr->gpshift = bytestream2_get_byte(&gb);
> - hdr->gpmask = (1 << hdr->gpshift) - 1;
> + if (hdr->gpshift >= 32) {
> + av_log(s, AV_LOG_ERROR, "Too large gpshift %d (>= 32).\n",
> + hdr->gpshift);
> + return AVERROR_INVALIDDATA;
> + }
> + hdr->gpmask = (1U << hdr->gpshift) - 1;
>
> hdr->format.depth = 8 + 2*(bytestream2_get_byte(&gb)-1);
>
> diff --git a/libavformat/oggparsetheora.c b/libavformat/oggparsetheora.c
> index 6e6a362..5f057c3 100644
> --- a/libavformat/oggparsetheora.c
> +++ b/libavformat/oggparsetheora.c
> @@ -108,7 +108,7 @@ static int theora_header(AVFormatContext *s, int idx)
> skip_bits(&gb, 2);
>
> thp->gpshift = get_bits(&gb, 5);
> - thp->gpmask = (1 << thp->gpshift) - 1;
> + thp->gpmask = (1U << thp->gpshift) - 1;
>
> st->codec->codec_type = AVMEDIA_TYPE_VIDEO;
> st->codec->codec_id = AV_CODEC_ID_THEORA;
LGTM
thx
[...]
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