CVEvulnerability
CVE-2026-89751
- Status
- Received
- Published
- 2026-09-11
- Last modified
- 2026-10-19
- Assigner
- 416baaa9-dc9f-4396-8d5f-8c081fb06d67
Description
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.
References
- https://git.kernel.org/stable/c/0f63e656b1c679d32ac595de29d10c03efca6a25 git.kernel.org
- https://git.kernel.org/stable/c/220011fe95fc78b2bc2d7d43893bc73957a5c811 git.kernel.org
- https://git.kernel.org/stable/c/222b7005e4519f633b4cd666226256abbab46a1a git.kernel.org
- https://git.kernel.org/stable/c/bb45f705c4440dd3c689328319b88dd28770bbb8 git.kernel.org
- https://git.kernel.org/stable/c/c4a22154870813d10aa0b4c734a574c726f9d4b0 git.kernel.org
- https://git.kernel.org/stable/c/c6875423ad849ac234ab9812eb72f37ff8a490b4 git.kernel.org