CVE-2026-89450
iommu/tegra241-cmdqv: Reject a vSID wider than the SID_MATCH field
In the Linux kernel, the following vulnerability has been resolved: iommu/tegra241-cmdqv: Reject a vSID wider than the SID_MATCH field tegra241_vintf_init_vsid() programs the guest-provided vSID into SID_MATCH, whose VIRT_SID field spans bits [20:1] with bit 0 as the match-enable flag. The HW therefore matches only a 20-bit Stream ID. The bound check rejects only virt_sid > UINT_MAX, which admits a value far wider than the field. The write "virt_sid << 1 | 0x1" then drops every bit above 20: a virt_sid of 0x80000000 lands as SID_MATCH = 0x1, a valid match on vSID 0, so the entry aliases the wrong Stream ID. Because vdev->virt_id is guest-controlled, a VMM can trigger it. Validate virt_sid against the field width with FIELD_MAX(), and program the register with FIELD_PREP() so the value and the field stay consistent.
| Vendor | linux |
| Product | linux |
| Ecosystems | |
| Industries | Technology |
| Published | Sep 11, 2026 |
| Last Updated | Sep 13, 2026 |
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CVSS v3 Breakdown
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:H