CVE-2026-31751

MEDIUM

comedi: dt2815: add hardware detection to prevent crash

Title source: cna
STIX 2.1

Description

In the Linux kernel, the following vulnerability has been resolved: comedi: dt2815: add hardware detection to prevent crash The dt2815 driver crashes when attached to I/O ports without actual hardware present. This occurs because syzkaller or users can attach the driver to arbitrary I/O addresses via COMEDI_DEVCONFIG ioctl. When no hardware exists at the specified port, inb() operations return 0xff (floating bus), but outb() operations can trigger page faults due to undefined behavior, especially under race conditions: BUG: unable to handle page fault for address: 000000007fffff90 #PF: supervisor write access in kernel mode #PF: error_code(0x0002) - not-present page RIP: 0010:dt2815_attach+0x6e0/0x1110 Add hardware detection by reading the status register before attempting any write operations. If the read returns 0xff, assume no hardware is present and fail the attach with -ENODEV. This prevents crashes from outb() operations on non-existent hardware.

Scores

CVSS v3 4.7
EPSS 0.0009
EPSS Percentile 0.5%
Attack Vector LOCAL
CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:N/I:N/A:H

Details

CWE
CWE-362
Status published
Products (35)
linux/Kernel 2.6.30 - 5.10.253linux
linux/Kernel 5.11.0 - 5.15.203linux
linux/Kernel 5.16.0 - 6.1.168linux
linux/Kernel 6.13.0 - 6.18.22linux
linux/Kernel 6.19.0 - 6.19.12linux
linux/Kernel 6.2.0 - 6.6.134linux
linux/Kernel 6.7.0 - 6.12.81linux
Linux/Linux < 2.6.30
Linux/Linux 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 - 0dcf33994b8dcf3db36530fb7e2cf9f89e5cbac3
Linux/Linux 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 - 34b13250c618d7441508c6ef369144aa8a9b9bfa
... and 25 more
Published May 01, 2026
Tracked Since May 01, 2026