{ "schema_version": "1.6.1", "id": "RPI-CVE-2026-68222", "modified": "2026-10-09T11:39:44Z", "upstream": [ "CVE-2026-68222" ], "published": "2026-08-10T12:08:00Z", "summary": "media: msi2500: Return queued buffers on start_streaming() failure", "details": "In the Linux kernel, the following vulnerability has been resolved:\n\nmedia: msi2500: Return queued buffers on start_streaming() failure\n\nThe vb2 framework hands buffers to the driver via buf_queue() before\ncalling start_streaming(). If start_streaming() returns an error\nwithout first returning those buffers via vb2_buffer_done(),\nvb2_start_streaming() fires WARN_ON(owned_by_drv_count) and the queued\nbuffers leak.\n\nmsi2500_start_streaming() had five error paths that all hit this trap\nand were further tangled by ret-overwriting between calls:\n\n - -ENODEV when the USB device was already disconnected\n - -ERESTARTSYS when mutex_lock_interruptible() was interrupted\n - msi2500_set_usb_adc() failure: ret was silently overwritten by\n the next call (msi2500_isoc_init), so the error was lost entirely\n - msi2500_isoc_init() failure: cleanup_queued_bufs was called, but\n the function then fell through to msi2500_ctrl_msg() and again\n masked the original error by overwriting ret\n - msi2500_ctrl_msg(CMD_START_STREAMING) failure: no cleanup at all,\n leaving isoc URBs submitted with no way for the driver to consume\n them\n\nConsolidate the error paths into a small goto chain. Every failure\nnow stops the function, drains the queued-buffer list, and returns\nthe real error code. The ctrl_msg failure path also rolls back the\npreceding msi2500_isoc_init() via msi2500_isoc_cleanup() before\nunlocking and draining.\n\nThe cleanup helper takes a vb2_buffer_state argument so that the\nstart_streaming error paths can pass VB2_BUF_STATE_QUEUED (as\nexpected by userspace on start_streaming failure) while stop_streaming\nkeeps its existing VB2_BUF_STATE_ERROR semantics.\n\nThis mirrors the uvcvideo fix in commit 4cf3b6fd54eb (\"media: uvcvideo:\nReturn queued buffers on start_streaming() failure\").", "severity": [ { "type": "CVSS_V3", "score": "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H" } ], "affected": [ { "package": { "ecosystem": "Raspberry Pi OS:12", "name": "linux" }, "versions": [ "1:6.1.47-1+rpt4" ], "ecosystem_specific": { "binaries": [ { "binary_name": "linux-image-6.1.0-rpi3-rpi-2712", "binary_version": "1:6.1.47-1+rpt4" }, { "binary_name": "linux-image-6.1.0-rpi3-rpi-v6", "binary_version": "1:6.1.47-1+rpt4" }, { "binary_name": "linux-image-6.1.0-rpi3-rpi-v7", "binary_version": "1:6.1.47-1+rpt4" }, { "binary_name": "linux-image-6.1.0-rpi3-rpi-v7l", "binary_version": "1:6.1.47-1+rpt4" }, { "binary_name": "linux-image-6.1.0-rpi3-rpi-v8", "binary_version": "1:6.1.47-1+rpt4" } ] }, "database_specific": { "per_version": { "1:6.1.47-1+rpt4": { "linux_commit": "655fc658a15ae7a6f37103754adb39ba52a9a14e", "upstream_version": "6.1.47", "assessment": "commit ancestry (strak rule)", "upstream_fixed": "6.1.183", "compiled_filter": false } } } } ], "references": [ { "type": "ADVISORY", "url": "https://www.cve.org/CVERecord?id=CVE-2026-68222" }, { "type": "FIX", "url": "https://git.kernel.org/stable/c/c74b680704baecea4620c0774de473069e0bc4e8" }, { "type": "FIX", "url": "https://git.kernel.org/stable/c/2d10eedb786a13f91d76e11320fabb0bf712519f" }, { "type": "FIX", "url": "https://git.kernel.org/stable/c/2de14ddb4fea04ca616403a6ba81c5e8099e9b9e" }, { "type": "FIX", "url": "https://git.kernel.org/stable/c/1d58229b330b7f67fbfa07e0f2a8a51fbeafaa9a" }, { "type": "FIX", "url": "https://git.kernel.org/stable/c/bab9d5a67d4db96ae8c187b92b37979911302a10" }, { "type": "FIX", "url": "https://git.kernel.org/stable/c/264b5380c4f8aa92dbc2983ecd2b627f1d5e0061" }, { "type": "FIX", "url": "https://git.kernel.org/stable/c/3673cb0a5711e910074d69201da9e1535c03f97a" }, { "type": "FIX", "url": "https://git.kernel.org/stable/c/7201c17786a498497bca57752883b90914d405ac" } ], "database_specific": { "source": "https://git.kernel.org/pub/scm/linux/security/vulns.git", "upstream_modified": "2026-08-19T16:47:12Z", "severity": { "source": "kernel CNA", "cvss_v3_score": 7.8, "cvss_v3_severity": "High", "scenario": "AV:L - The vulnerable code is reached only through a local VIDIOC_STREAMON ioctl on the msi2500 SDR character device /dev/swradioN; no network or remote input is involved, and the failure paths are driven from a local process's syscalls.\nAC:L - The attacker controls both sides of the trigger: hold dev->v4l2_lock from a second thread and send a signal to the STREAMON thread so mutex_lock_interruptible() returns -ERESTARTSYS, hitting the leaking error path deterministically and repeatably.\nPR:L - Only an unprivileged local user with access to the V4L2/SDR device node is needed; on desktop, Android and embedded systems these nodes are granted to the logged-in seat or a device group, and no capability check guards STREAMON.\nUI:N - The whole sequence (REQBUFS, QBUF, STREAMON, signal, repeat) is performed by the attacker's own process; no victim action such as plugging in hardware or opening a file is required.\nS:U - The corruption is confined to kernel memory managed by the same kernel security authority; no VM, IOMMU or sandbox boundary is crossed.\nC:H - Buffers left on dev->queued_bufs after the vb2 core reclaims and later frees them become dangling pointers reused by cleanup_queued_bufs()/get_next_fill_buf(), giving a use-after-free that can be groomed to read reclaimed kernel heap contents back into userspace buffers.\nI:H - The stale list entries permit list_add_tail() on an already-linked node (list corruption) and vb2_buffer_done()/isoc-handler writes into freed objects, yielding attacker-influenced kernel heap writes exploitable for control-flow hijacking.\nA:H - At minimum the missing buffer return trips WARN_ON(owned_by_drv_count) (fatal with panic_on_warn) and leaks buffers; the resulting list corruption and use-after-free reliably oops or hang the kernel." } } }