{"cve":"CVE-2026-90244","nvd":{"published":"2026-09-17T17:17:20.400","modified":"2026-10-19T09:19:14.897","status":"Received","description":"In the Linux kernel, the following vulnerability has been resolved:\n\niommu/dma: Restore locking around msi_page_list\n\nUnlike a group's default domain, which is always freshly allocated\nand privately owned (iommu_group_alloc_default_domain()), VFIO type1's\nlegacy container merges any newly attached group into an existing\ndomain whenever their iommu_ops and cache-coherency enforcement match.\n\niommu_dma_get_msi_page() only asserts the caller's own group mutex is\nheld (iommu_group_mutex_assert()). On an IOMMU that publishes\nIOMMU_RESV_SW_MSI, e.g. ARM SMMU, a VM with two such devices assigned\nthrough the legacy container can have their guest drivers probe and\nallocate MSIs in parallel; each host-side VFIO_DEVICE_SET_IRQS lands\non a different device fd and group mutex, but both devices' domains\nare the same merged domain, so both can enter\niommu_dma_get_msi_page() concurrently and corrupt msi_page_list.\n\ncommit 288683c92b1a (\"iommu: Make iommu_dma_prepare_msi() into a\ngeneric operation\") dropped the prior msi_prepare_lock on the\nreasoning that \"each iommu_domain is unique to a group,\" which holds\nfor default domains but not this VFIO type1 case. Restore the static\nlock, since it's only guarding a corner case and will likely never\nbe contended.\n\niommufd avoids the equivalent problem by having its own callers\n(iommufd_sw_map_msi()) take a ctx-wide sw_msi_lock before ever\nreaching the shared list. VFIO type1 can't mirror that since it\ndispatches to iommu_dma_sw_msi() which is outside VFIO's jurisdiction.","cvss_v4":null,"cvss_v3":{"version":"3.1","vector":"CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H","score":7.8},"cwes":[],"references":["https://git.kernel.org/stable/c/2af1e99ec14d226d66ceb9f16c663ee2568e6676","https://git.kernel.org/stable/c/5a9e89ea34e0e34ac5d7e949042d665533549e40","https://git.kernel.org/stable/c/e3c53e9173a47d5ce1fae020f2c6b1fb3c1123c2"],"products":[],"source":"nvd","synced_at":"2026-10-19T22:55:23.253742848+00:00"},"epss":{"cve":"CVE-2026-90244","score":0.00173,"percentile":0.06719,"date":"2026-10-25"},"kev":null,"osv":[],"attribution":["This product uses the NVD API but is not endorsed or certified by the NVD.","EPSS scores: FIRST Exploit Prediction Scoring System, https://www.first.org/epss","Known exploited vulnerabilities: CISA Known Exploited Vulnerabilities Catalog, https://www.cisa.gov/known-exploited-vulnerabilities-catalog","Package advisories: OSV (https://osv.dev), from the GitHub Advisory Database, PyPA, Go, RustSec and other ecosystem databases, under CC-BY 4.0 or CC0","CVE records: the CVE Program's CVE List (https://www.cve.org), under its terms of use (https://www.cve.org/Legal/TermsOfUse). CVE is a registered trademark of The MITRE Corporation; this product is not affiliated with the CVE Program."]}