{
    "dataType": "CVE_RECORD",
    "dataVersion": "5.2",
    "cveMetadata": {
        "cveId": "CVE-2025-21870",
        "assignerOrgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
        "state": "PUBLISHED",
        "assignerShortName": "Linux",
        "dateReserved": "2024-12-29T08:45:45.781Z",
        "datePublished": "2025-03-27T13:38:22.849Z",
        "dateUpdated": "2026-08-05T11:55:01.457Z"
    },
    "containers": {
        "cna": {
            "providerMetadata": {
                "orgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
                "shortName": "Linux",
                "dateUpdated": "2026-08-05T11:55:01.457Z"
            },
            "descriptions": [
                {
                    "lang": "en",
                    "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nASoC: SOF: ipc4-topology: Harden loops for looking up ALH copiers\n\nOther, non DAI copier widgets could have the same  stream name (sname) as\nthe ALH copier and in that case the copier->data is NULL, no alh_data is\nattached, which could lead to NULL pointer dereference.\nWe could check for this NULL pointer in sof_ipc4_prepare_copier_module()\nand avoid the crash, but a similar loop in sof_ipc4_widget_setup_comp_dai()\nwill miscalculate the ALH device count, causing broken audio.\n\nThe correct fix is to harden the matching logic by making sure that the\n1. widget is a DAI widget - so dai = w->private is valid\n2. the dai (and thus the copier) is ALH copier"
                }
            ],
            "metrics": [
                {
                    "cvssV3_1": {
                        "version": "3.1",
                        "vectorString": "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H",
                        "baseScore": 7.8,
                        "baseSeverity": "HIGH"
                    },
                    "scenarios": [
                        {
                            "lang": "en",
                            "value": "AV:L - The vulnerable code is reached only through the local ALSA PCM character device (`/dev/snd/pcmC*D*`) via `SNDRV_PCM_IOCTL_HW_PARAMS`, which flows into `sof_pcm_hw_params()` → `sof_prepare_widgets_in_path()` → `sof_ipc4_prepare_copier_module()`. There is no network or remote-peer input on this path.\nAC:L - On an affected system (Intel SoundWire/ALH platform whose topology has a non-DAI widget sharing an `sname` with an ALH copier), the attacker simply opens the PCM device and issues hw_params — the faulty widget-matching loop runs deterministically every time, with no race to win and no memory layout to guess.\nPR:L - Only access to the sound PCM device node is required, which any logged-in desktop user gets via logind ACLs and any `audio`-group member gets on servers/embedded systems; no capability check exists anywhere along the hw_params → widget-prepare path.\nUI:N - The attacker performs the entire sequence themselves by opening the PCM device and calling hw_params; no victim action, mount, or file-open by another user is needed.\nS:U - The type confusion and heap corruption occur in kernel memory within the same security authority as the attacking local user; no VM, IOMMU, or sandbox boundary is crossed.\nC:H - The type confusion causes `dai->private` to be read from a mismatched struct and dereferenced as `struct sof_ipc4_copier *`, disclosing arbitrary kernel heap contents, and the inflated `config_length` makes the `memcpy()` at ipc4-topology.c:2211 read past the 136-byte blob allocation into the IPC payload.\nI:H - This is a type confusion (`w->private` treated as `struct snd_sof_dai` when it is not), and the unbounded `blob->alh_cfg.mapping[i++]` loop can write past the fixed 16-entry array in a kmalloc-192 object, giving a heap out-of-bounds write that is leverageable for control-flow corruption.\nA:H - The commit explicitly documents a NULL/wild pointer dereference causing a kernel oops, and the miscounted `device_count` additionally corrupts the ALH blob and yields `GENMASK(-1, 0)` via a zero `step` — any of which panics the kernel and can be re-triggered at will."
                        }
                    ]
                }
            ],
            "affected": [
                {
                    "product": "Linux",
                    "vendor": "Linux",
                    "defaultStatus": "unaffected",
                    "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
                    "programFiles": [
                        "sound/soc/sof/ipc4-topology.c"
                    ],
                    "versions": [
                        {
                            "version": "a150345aa758492e05d2934f318ce7c2566b1cfe",
                            "lessThan": "87c8768a96092ce75cd47fe076db5080db7ac515",
                            "status": "affected",
                            "versionType": "git"
                        },
                        {
                            "version": "a150345aa758492e05d2934f318ce7c2566b1cfe",
                            "lessThan": "93c6c2e5801aab09ef1ef99f248f3cd323c3f152",
                            "status": "affected",
                            "versionType": "git"
                        },
                        {
                            "version": "a150345aa758492e05d2934f318ce7c2566b1cfe",
                            "lessThan": "6fd60136d256b3b948333ebdb3835f41a95ab7ef",
                            "status": "affected",
                            "versionType": "git"
                        }
                    ]
                },
                {
                    "product": "Linux",
                    "vendor": "Linux",
                    "defaultStatus": "affected",
                    "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
                    "programFiles": [
                        "sound/soc/sof/ipc4-topology.c"
                    ],
                    "versions": [
                        {
                            "version": "6.0",
                            "status": "affected"
                        },
                        {
                            "version": "0",
                            "lessThan": "6.0",
                            "status": "unaffected",
                            "versionType": "semver"
                        },
                        {
                            "version": "6.12.17",
                            "lessThanOrEqual": "6.12.*",
                            "status": "unaffected",
                            "versionType": "semver"
                        },
                        {
                            "version": "6.13.5",
                            "lessThanOrEqual": "6.13.*",
                            "status": "unaffected",
                            "versionType": "semver"
                        },
                        {
                            "version": "6.14",
                            "lessThanOrEqual": "*",
                            "status": "unaffected",
                            "versionType": "original_commit_for_fix"
                        }
                    ]
                }
            ],
            "cpeApplicability": [
                {
                    "nodes": [
                        {
                            "operator": "OR",
                            "negate": false,
                            "cpeMatch": [
                                {
                                    "vulnerable": true,
                                    "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                                    "versionStartIncluding": "6.0",
                                    "versionEndExcluding": "6.12.17"
                                },
                                {
                                    "vulnerable": true,
                                    "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                                    "versionStartIncluding": "6.0",
                                    "versionEndExcluding": "6.13.5"
                                },
                                {
                                    "vulnerable": true,
                                    "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                                    "versionStartIncluding": "6.0",
                                    "versionEndExcluding": "6.14"
                                }
                            ]
                        }
                    ]
                }
            ],
            "references": [
                {
                    "url": "https://git.kernel.org/stable/c/87c8768a96092ce75cd47fe076db5080db7ac515"
                },
                {
                    "url": "https://git.kernel.org/stable/c/93c6c2e5801aab09ef1ef99f248f3cd323c3f152"
                },
                {
                    "url": "https://git.kernel.org/stable/c/6fd60136d256b3b948333ebdb3835f41a95ab7ef"
                }
            ],
            "title": "ASoC: SOF: ipc4-topology: Harden loops for looking up ALH copiers",
            "x_generator": {
                "engine": "bippy-1.2.0"
            }
        }
    }
}