{
    "dataType": "CVE_RECORD",
    "dataVersion": "5.2",
    "cveMetadata": {
        "cveId": "CVE-2022-49963",
        "assignerOrgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
        "state": "PUBLISHED",
        "assignerShortName": "Linux",
        "dateReserved": "2025-06-18T10:57:27.384Z",
        "datePublished": "2025-06-18T11:00:24.021Z",
        "dateUpdated": "2026-08-05T08:56:54.694Z"
    },
    "containers": {
        "cna": {
            "providerMetadata": {
                "orgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
                "shortName": "Linux",
                "dateUpdated": "2026-08-05T08:56:54.694Z"
            },
            "descriptions": [
                {
                    "lang": "en",
                    "value": "In the Linux kernel, the following vulnerability has been resolved:\n\ndrm/i915/ttm: fix CCS handling\n\nCrucible + recent Mesa seems to sometimes hit:\n\nGEM_BUG_ON(num_ccs_blks > NUM_CCS_BLKS_PER_XFER)\n\nAnd it looks like we can also trigger this with gem_lmem_swapping, if we\nmodify the test to use slightly larger object sizes.\n\nLooking closer it looks like we have the following issues in\nmigrate_copy():\n\n  - We are using plain integer in various places, which we can easily\n    overflow with a large object.\n\n  - We pass the entire object size (when the src is lmem) into\n    emit_pte() and then try to copy it, which doesn't work, since we\n    only have a few fixed sized windows in which to map the pages and\n    perform the copy. With an object > 8M we therefore aren't properly\n    copying the pages. And then with an object > 64M we trigger the\n    GEM_BUG_ON(num_ccs_blks > NUM_CCS_BLKS_PER_XFER).\n\nSo it looks like our copy handling for any object > 8M (which is our\nCHUNK_SZ) is currently broken on DG2.\n\nTestcase: igt@gem_lmem_swapping\n(cherry picked from commit 8676145eb2f53a9940ff70910caf0125bd8a4bc2)"
                }
            ],
            "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 bug is reached via i915 GEM ioctls on a local DRM render node (GEM_CREATE_EXT of lmem-only objects plus TTM eviction into intel_context_migrate_copy), not via network packet processing.\nAC:L - An attacker can reliably create Flat-CCS lmem objects larger than CHUNK_SZ (8M) and force lmem pressure to trigger eviction; the failure is deterministic once migrate_copy runs on such an object, as shown by gem_lmem_swapping and Mesa/Crucible hits.\nPR:L - Triggering requires only unprivileged access to /dev/dri/renderD* (DRM_RENDER_ALLOW for GEM_CREATE_EXT and related ioctls), not root or init-namespace capabilities.\nUI:N - The attacker opens the render node and allocates/evicts their own objects; no separate victim action is required.\nS:U - Impact stays within the host kernel/GPU driver authority (migration PPGTT corruption and GEM buffer corruption), not a guest-to-host or IOMMU-boundary escape.\nC:H - Oversized blits past the fixed 8M windows can read the migrate VM’s self-mapped PTE region and adjacent mappings into attacker-readable smem backup pages, and can mishandle CCS/metadata during eviction of other clients’ buffers under memory pressure.\nI:H - The same oversized XY copy can write past the destination window into the migration page tables and leave incomplete/incorrect main and CCS copies, corrupting GPU PTEs and buffer contents with no CCS-capable CPU memcpy fallback.\nA:H - Out-of-bounds GTT access and invalid CCS transfer sizing can hang or wedge the GPU (and trip GEM_BUG_ON on debug builds), denying GPU service to the system."
                        }
                    ]
                }
            ],
            "affected": [
                {
                    "product": "Linux",
                    "vendor": "Linux",
                    "defaultStatus": "unaffected",
                    "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
                    "programFiles": [
                        "drivers/gpu/drm/i915/gt/intel_migrate.c"
                    ],
                    "versions": [
                        {
                            "version": "da0595ae91da837929a00470ab40546090e5b9ae",
                            "lessThan": "97434cb55bd884bd268626ec41489f79b261b2d4",
                            "status": "affected",
                            "versionType": "git"
                        },
                        {
                            "version": "da0595ae91da837929a00470ab40546090e5b9ae",
                            "lessThan": "8d905254162965c8e6be697d82c7dbf5d08f574d",
                            "status": "affected",
                            "versionType": "git"
                        }
                    ]
                },
                {
                    "product": "Linux",
                    "vendor": "Linux",
                    "defaultStatus": "affected",
                    "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
                    "programFiles": [
                        "drivers/gpu/drm/i915/gt/intel_migrate.c"
                    ],
                    "versions": [
                        {
                            "version": "5.19",
                            "status": "affected"
                        },
                        {
                            "version": "0",
                            "lessThan": "5.19",
                            "status": "unaffected",
                            "versionType": "semver"
                        },
                        {
                            "version": "5.19.8",
                            "lessThanOrEqual": "5.19.*",
                            "status": "unaffected",
                            "versionType": "semver"
                        },
                        {
                            "version": "6.0",
                            "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": "5.19",
                                    "versionEndExcluding": "5.19.8"
                                },
                                {
                                    "vulnerable": true,
                                    "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                                    "versionStartIncluding": "5.19",
                                    "versionEndExcluding": "6.0"
                                }
                            ]
                        }
                    ]
                }
            ],
            "references": [
                {
                    "url": "https://git.kernel.org/stable/c/97434cb55bd884bd268626ec41489f79b261b2d4"
                },
                {
                    "url": "https://git.kernel.org/stable/c/8d905254162965c8e6be697d82c7dbf5d08f574d"
                }
            ],
            "title": "drm/i915/ttm: fix CCS handling",
            "x_generator": {
                "engine": "bippy-1.2.0"
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}