{"id":"AZL-101231","summary":"CVE-2026-89901 affecting package kernel 6.6.150.1-1","details":"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-\u003eudev 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-\u003eudev:\n\n  airspy_stop_streaming()\n    airspy_ctrl_msg(s, CMD_RECEIVER_MODE, 0, 0, NULL, 0)\n      usb_sndctrlpipe(s-\u003eudev, 0)         /* NULL deref */\n    airspy_free_stream_bufs(s)\n      usb_free_coherent(s-\u003eudev, ...)     /* NULL deref */\n\nThe airspy driver uses vb2_fop_release() in its file_operations, so\nreplace video_unregister_device(&s-\u003evdev) with\nvb2_video_unregister_device(&s-\u003evdev) and move it before clearing\ns-\u003eudev. 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-\u003eudev is still valid.\n\nvb2_video_unregister_device() locks vdev-\u003equeue-\u003elock (vb_queue_lock)\ninternally, and stop_streaming() locks v4l2_lock, so the previous outer\nmutex_lock(&s-\u003evb_queue_lock) / mutex_lock(&s-\u003ev4l2_lock) pair around\nthe unregister sequence would self-deadlock and has been removed. A\nshort v4l2_lock critical section around s-\u003eudev = 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/","modified":"2026-09-18T05:37:08Z","published":"2026-09-16T11:16:59Z","upstream":["CVE-2026-89901"],"references":[{"type":"WEB","url":"https://nvd.nist.gov/vuln/detail/CVE-2026-89901"}],"affected":[{"package":{"name":"kernel","ecosystem":"Azure Linux:3","purl":"pkg:rpm/azure-linux/kernel"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"last_affected":"6.6.150.1-1"}]}],"database_specific":{"source":"https://github.com/microsoft/AzureLinuxVulnerabilityData/blob/main/osv/AZL-101231.json"}}],"schema_version":"1.9.0"}