[FFmpeg-devel] [PATCH] avcodec/libdav1d: fix setting AVFrame reordered_opaque

[Timo Rothenpieler]

On 17.10.2019 23:59, James Almer wrote:
> On 10/17/2019 6:43 PM, Andrey Semashev wrote:
>> On 2019-10-17 23:11, James Almer wrote:
>>> Actually reorder the values.
>>>
>>> Should effectively fix ticket #8300.
>>>
>>> Signed-off-by: James Almer <jamrial at gmail.com>
>>> ---
>>>    libavcodec/libdav1d.c | 21 ++++++++++++++++++++-
>>>    1 file changed, 20 insertions(+), 1 deletion(-)
>>>
>>> diff --git a/libavcodec/libdav1d.c b/libavcodec/libdav1d.c
>>> index 8aa248e6cd..87abdb4569 100644
>>> --- a/libavcodec/libdav1d.c
>>> +++ b/libavcodec/libdav1d.c
>>> @@ -191,6 +191,24 @@ static int libdav1d_receive_frame(AVCodecContext
>>> *c, AVFrame *frame)
>>>                  pkt.buf = NULL;
>>>                av_packet_unref(&pkt);
>>> +
>>> +            if (c->reordered_opaque != AV_NOPTS_VALUE) {
>>> +                AVBufferRef *reordered_opaque =
>>> av_buffer_alloc(sizeof(c->reordered_opaque));
>>> +
>>> +                if (!reordered_opaque) {
>>> +                    dav1d_data_unref(data);
>>> +                    return AVERROR(ENOMEM);
>>> +                }
>>> +
>>> +                *reordered_opaque->data = c->reordered_opaque;
>>
>> This slices int64_t to uint8_t. Should memcpy instead.
> 
> Good catch. Changed locally to
> 
> *(int64_t *)reordered_opaque->data = c->reordered_opaque;

Doesn't that violate strict aliasing rules?
I'd just use memcpy.