{
    "dataType": "CVE_RECORD",
    "dataVersion": "5.2",
    "cveMetadata": {
        "cveId": "CVE-2026-98919",
        "assignerOrgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
        "state": "PUBLISHED",
        "assignerShortName": "Linux",
        "dateReserved": "2026-09-25T10:25:14.380Z",
        "datePublished": "2026-10-23T12:01:55.092Z",
        "dateUpdated": "2026-10-23T12:05:08.723Z"
    },
    "containers": {
        "cna": {
            "providerMetadata": {
                "orgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
                "shortName": "Linux",
                "dateUpdated": "2026-10-23T12:05:08.723Z"
            },
            "descriptions": [
                {
                    "lang": "en",
                    "value": "In the Linux kernel, the following vulnerability has been resolved:\n\ndrm/xe: harden adjust_idledly() against divide-by-zero and overflow\n\nadjust_idledly() has several corner-case issues flagged during review:\n\n  1. If xe_gt_clock_init() failed to recognise the crystal clock,\n     gt->info.timestamp_base is 0, which makes idledly_units_ps also 0.\n     The subsequent DIV_ROUND_CLOSEST(..., idledly_units_ps) is then a\n     divide-by-zero and panics the kernel.\n\n  2. The tick-to-ns conversions are done in u32:\n        idledly * idledly_units_ps, (maxcnt - 1) * 1000\n     Both overflow u32 before DIV_ROUND_CLOSEST() sees them.\n\n  3. If IDLE_WAIT_TIME reads back as 0, maxcnt evaluates to 0 and\n     the maxcnt - 1 clamp wraps to 0xFFFFFFFF in u32.\n\n  4. The register only stores whole ticks, so the clamped ns value has\n     to be converted to ticks and back. DIV_ROUND_CLOSEST() can round\n     that conversion up past maxcnt:\n\n       maxcnt = 640 ns, one tick = 666664 ps\n\n       clamp:        maxcnt - 1        = 639 ns\n       ns -> ticks:  639000 / 666664   = 0.958 -> rounds to 1 tick\n       tick -> ns:    1 * 666664 / 1000 = 667 ns\n\n     667 ns is programmed into RING_IDLEDLY, but 667 >= maxcnt (640),\n     so xe_gt_WARN_ON() fires again on every subsequent init.\n\nReturn early if timestamp_base is 0 (the unknown-crystal path).\nDo the conversions in u64 via the *_ULL() helpers so they cannot wrap.\nClamp with a floor (DIV_ROUND_DOWN_ULL) so the programmed delay stays\nstrictly below maxcnt, and guard the maxcnt == 0 case with a zero delay\nwhile still writing RING_IDLEDLY so INHIBIT_SWITCH_UNTIL_PREEMPTED is\ncleared.\n\nv2: Drop the redundant warn on the timestamp_base == 0 path;\n    xe_gt_clock_init() already warns on an unrecognised crystal clock.\n    Keep the early return to avoid the divide-by-zero. - Vinay\n\nv3: Field-mask the RING_IDLEDLY write with REG_FIELD_PREP(IDLE_DELAY, ...)\n    instead of writing the raw tick count, which could clobber\n    INHIBIT_SWITCH_UNTIL_PREEMPTED and reserved bits. Split the\n    inhibit-switch clear from the maxcnt clamp so a set inhibit bit no\n    longer forces a needless delay overwrite when the delay itself is\n    already valid. Use gt_to_xe(gt) instead of gt_to_xe(hwe->gt).\n\n(cherry picked from commit d864065ea25e9d12897c175de9176ce46677e176)"
                }
            ],
            "affected": [
                {
                    "product": "Linux",
                    "vendor": "Linux",
                    "defaultStatus": "unaffected",
                    "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
                    "programFiles": [
                        "drivers/gpu/drm/xe/xe_hw_engine.c"
                    ],
                    "versions": [
                        {
                            "version": "d2de4410a88ffc6053300d03041cc73b8c85dbaf",
                            "lessThan": "2bcbfc5e7bfa9cc76818c54db698da5bdc13d9ff",
                            "status": "affected",
                            "versionType": "git"
                        },
                        {
                            "version": "d2de4410a88ffc6053300d03041cc73b8c85dbaf",
                            "lessThan": "531d4cd03118224022dc21ae25af052ce2a9e267",
                            "status": "affected",
                            "versionType": "git"
                        },
                        {
                            "version": "d2de4410a88ffc6053300d03041cc73b8c85dbaf",
                            "lessThan": "90f467577ebc28c5bc4ba2f0f1b83a4419fb0740",
                            "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/xe/xe_hw_engine.c"
                    ],
                    "versions": [
                        {
                            "version": "6.15",
                            "status": "affected"
                        },
                        {
                            "version": "0",
                            "lessThan": "6.15",
                            "status": "unaffected",
                            "versionType": "semver"
                        },
                        {
                            "version": "6.18.55",
                            "lessThanOrEqual": "6.18.*",
                            "status": "unaffected",
                            "versionType": "semver"
                        },
                        {
                            "version": "7.2.9",
                            "lessThanOrEqual": "7.2.*",
                            "status": "unaffected",
                            "versionType": "semver"
                        },
                        {
                            "version": "7.3",
                            "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": "6.15",
                                    "versionEndExcluding": "6.18.55"
                                },
                                {
                                    "vulnerable": true,
                                    "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                                    "versionStartIncluding": "6.15",
                                    "versionEndExcluding": "7.2.9"
                                },
                                {
                                    "vulnerable": true,
                                    "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                                    "versionStartIncluding": "6.15",
                                    "versionEndExcluding": "7.3"
                                }
                            ]
                        }
                    ]
                }
            ],
            "references": [
                {
                    "url": "https://git.kernel.org/stable/c/2bcbfc5e7bfa9cc76818c54db698da5bdc13d9ff"
                },
                {
                    "url": "https://git.kernel.org/stable/c/531d4cd03118224022dc21ae25af052ce2a9e267"
                },
                {
                    "url": "https://git.kernel.org/stable/c/90f467577ebc28c5bc4ba2f0f1b83a4419fb0740"
                }
            ],
            "title": "drm/xe: harden adjust_idledly() against divide-by-zero and overflow",
            "x_generator": {
                "engine": "bippy-1.2.0"
            }
        }
    }
}