CVEvulnerability
CVE-2026-89450
8.8 HIGH
Official page ↗
- Status
- Received
- Published
- 2026-09-11
- Last modified
- 2026-10-19
- Assigner
- 416baaa9-dc9f-4396-8d5f-8c081fb06d67
- CVSS 3.1 (416baaa9-dc9f-4396-8d5f-8c081fb06d67)
- 8.8 HIGH — CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:H
Description
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.