{"id":"CVE-2026-89901","published":"2026-09-16T11:16:59.003","lastModified":"2026-09-16T11:16:59.003","description":"In the Linux kernel, the following vulnerability has been resolved:\n\nmedia: airspy: use vb2_video_unregister_device() on disconnect to fix NULL deref\n\nairspy_disconnect() clears s->udev under v4l2_lock, but\nairspy_stop_streaming() unconditionally calls airspy_ctrl_msg() and\nairspy_free_stream_bufs() afterwards. If a streaming user closes the\ndevice after disconnect, stop_streaming() runs and dereferences the\nNULL s->udev:\n\n  airspy_stop_streaming()\n    airspy_ctrl_msg(s, CMD_RECEIVER_MODE, 0, 0, NULL, 0)\n      usb_sndctrlpipe(s->udev, 0)         /* NULL deref */\n    airspy_free_stream_bufs(s)\n      usb_free_coherent(s->udev, ...)     /* NULL deref */\n\nThe airspy driver uses vb2_fop_release() in its file_operations, so\nreplace video_unregister_device(&s->vdev) with\nvb2_video_unregister_device(&s->vdev) and move it before clearing\ns->udev. vb2_video_unregister_device() releases the vb2 queue, which\nsynchronously runs airspy_stop_streaming() if streaming is active, so\nthe URBs, coherent DMA stream buffers and the hardware stop control\nmessage all execute while s->udev is still valid.\n\nvb2_video_unregister_device() locks vdev->queue->lock (vb_queue_lock)\ninternally, and stop_streaming() locks v4l2_lock, so the previous outer\nmutex_lock(&s->vb_queue_lock) / mutex_lock(&s->v4l2_lock) pair around\nthe unregister sequence would self-deadlock and has been removed. A\nshort v4l2_lock critical section around s->udev = NULL remains so any\nioctl path that still holds the file descriptor sees coherent state.\n\nIssue identified by automated review of the INV-003 series at\nhttps://sashiko.dev/","cvssScore":null,"cvssSeverity":null,"cvssVector":null,"cwes":[],"vendors":[],"products":[],"references":[{"url":"https://git.kernel.org/stable/c/155d0378ae0d6305cc4840583a6b42d2d0595bff","tags":[]},{"url":"https://git.kernel.org/stable/c/297fee023f46d771a844520675692ea089d80d9d","tags":[]},{"url":"https://git.kernel.org/stable/c/2f378dc45e685fc825d2dd08e7864666d6fcc009","tags":[]},{"url":"https://git.kernel.org/stable/c/6e4ea90fdc6608cd5fac342e146ab6ae15d430bc","tags":[]},{"url":"https://git.kernel.org/stable/c/75089cea32e5055773bd13116236d08fdc98678a","tags":[]},{"url":"https://git.kernel.org/stable/c/a9a8c37ddda9fa3687b142be9098e1c37b8faf35","tags":[]},{"url":"https://git.kernel.org/stable/c/c6749ac8f59cc80eb1b2d52f167fdf13e12655cc","tags":[]},{"url":"https://git.kernel.org/stable/c/c9081e2655188d2d134a741aec837dc70439d505","tags":[]}],"exploitRefs":[],"hasPoc":false,"ai":null}