CVE-2026-89751

In the Linux kernel, the following vulnerability has been resolved: x86/tdx: Fix off-by-one in port I/O handling handle_in() and handle_out() in arch/x86/coco/tdx/tdx.c use: u64 mask = GENMASK(BITS_PER_BYTE * size, 0); GENMASK(h, l) includes bit h. For size=1 (INB), this produces GENMASK(8, 0) = 0x1FF (9 bits) instead of GENMASK(7, 0) = 0xFF (8 bits). The mask is one bit too wide for all I/O sizes. Fix the mask calculation.

CVSS

No CVSS.

References

Link	Resource
https://git.kernel.org/stable/c/0f63e656b1c679d32ac595de29d10c03efca6a25
https://git.kernel.org/stable/c/220011fe95fc78b2bc2d7d43893bc73957a5c811
https://git.kernel.org/stable/c/222b7005e4519f633b4cd666226256abbab46a1a
https://git.kernel.org/stable/c/bb45f705c4440dd3c689328319b88dd28770bbb8
https://git.kernel.org/stable/c/c4a22154870813d10aa0b4c734a574c726f9d4b0
https://git.kernel.org/stable/c/c6875423ad849ac234ab9812eb72f37ff8a490b4

Configurations

No configuration.

History

No history.

Information

Published : 2026-09-11 20:20

Updated : 2026-09-14 13:19

NVD link : CVE-2026-89751

Mitre link : CVE-2026-89751

CVE.ORG link : CVE-2026-89751

JSON object : View

Products Affected

No product.

CWE

No CWE.

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