From 7d9b21601ca3080cf63c55c435311de5f93f573f Mon Sep 17 00:00:00 2001 From: =?UTF-8?q?Kacper=20Michaj=C5=82ow?= Date: Tue, 22 Jul 2025 21:04:35 +0200 Subject: [PATCH] avcodec/d3d12va_encode: don't write garbage when there is no header MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit When codec->write_sequence_header is not defined, bit_len was undefined, and while data bufer was zeroed we could just overread it. Do nothing when we don't have anything to write. Signed-off-by: Kacper Michajłow --- libavcodec/d3d12va_encode.c | 27 +++++++++++++-------------- 1 file changed, 13 insertions(+), 14 deletions(-) diff --git a/libavcodec/d3d12va_encode.c b/libavcodec/d3d12va_encode.c index d99e960db6..64821da5f5 100644 --- a/libavcodec/d3d12va_encode.c +++ b/libavcodec/d3d12va_encode.c @@ -299,21 +299,20 @@ static int d3d12va_encode_issue(AVCodecContext *avctx, "header: %d.\n", err); goto fail; } + pic->header_size = (int)bit_len / 8; + pic->aligned_header_size = pic->header_size % ctx->req.CompressedBitstreamBufferAccessAlignment ? + FFALIGN(pic->header_size, ctx->req.CompressedBitstreamBufferAccessAlignment) : + pic->header_size; + + hr = ID3D12Resource_Map(pic->output_buffer, 0, NULL, (void **)&ptr); + if (FAILED(hr)) { + err = AVERROR_UNKNOWN; + goto fail; + } + + memcpy(ptr, data, pic->aligned_header_size); + ID3D12Resource_Unmap(pic->output_buffer, 0, NULL); } - - pic->header_size = (int)bit_len / 8; - pic->aligned_header_size = pic->header_size % ctx->req.CompressedBitstreamBufferAccessAlignment ? - FFALIGN(pic->header_size, ctx->req.CompressedBitstreamBufferAccessAlignment) : - pic->header_size; - - hr = ID3D12Resource_Map(pic->output_buffer, 0, NULL, (void **)&ptr); - if (FAILED(hr)) { - err = AVERROR_UNKNOWN; - goto fail; - } - - memcpy(ptr, data, pic->aligned_header_size); - ID3D12Resource_Unmap(pic->output_buffer, 0, NULL); } d3d12_refs.NumTexture2Ds = base_pic->nb_refs[0] + base_pic->nb_refs[1];