In the Linux kernel, the following vulnerability has been resolved:
ASoC: SOF: ipc4-topology: Refresh copier IPC payload before widget setup
The ipc_config_data buffer for copier widgets is built once during ipc_prepare (called from sof_pcm_setup_connected_widgets) and cached for reuse. For host copiers this buffer contains the copier_data with gtw_cfg.node_id (host DMA ID). For DAI copiers it additionally includes a dma_config_tlv trailer with stream_id and dma_channel_id for HDA link DMA.
On suspend/resume, both host and link DMA streams are released and re-allocated with potentially different stream tags. The underlying copier_data and dma_config_tlv structures are correctly updated by host_config and sdw_hda_dai_hw_params respectively. However, since the widget list (spcm->stream[].list) persists across suspend, sof_pcm_hw_params skips sof_pcm_setup_connected_widgets and ipc_prepare never runs again to rebuild ipc_config_data. The stale cached payload is then sent to firmware with boot-time DMA channel assignments, causing DMA channel conflicts that lead to firmware errors and crashes.
Fix this by refreshing copier_data and dma_config_tlv portions of ipc_config_data in sof_ipc4_widget_setup right before the IPC message is sent. This ensures the payload always reflects the current DMA state regardless of whether ipc_prepare ran.
For DAI copiers, the gtw_cfg.config_length in copier_data is temporarily inflated to include the TLV size (matching the ipc_config_data layout) before copying, then restored, mirroring what sof_ipc4_prepare_copier_module does when first building the buffer.