Linux EUVD-2026-55312

In the Linux kernel, the following vulnerability has been resolved:

media: stm32-dcmipp: Return queued buffers on start_streaming() failure

The vb2 framework hands buffers to the driver via buf_queue() before calling start_streaming(). If start_streaming() returns an error without first returning those buffers via vb2_buffer_done(), vb2_start_streaming() fires WARN_ON(owned_by_drv_count) and the queued buffers leak.

dcmipp_bytecap_start_streaming() returned -EINVAL when the source subdevice could not be resolved from the media graph, before pm_runtime_resume_and_get() and media_pipeline_start() had been called. The remaining error paths already converge on the err_buffer_done label, which calls dcmipp_bytecap_all_buffers_done(..., VB2_BUF_STATE_QUEUED). Jump to that label directly: the intermediate err_pm_put / err_media_pipeline_stop labels are skipped, which is correct because nothing they would undo has happened yet.

This mirrors the uvcvideo fix in commit 4cf3b6fd54eb ("media: uvcvideo: Return queued buffers on start_streaming() failure").