CVE-2026-43340

MEDIUM

comedi: Reinit dev->spinlock between attachments to low-level drivers

Title source: cna
STIX 2.1

Description

In the Linux kernel, the following vulnerability has been resolved: comedi: Reinit dev->spinlock between attachments to low-level drivers `struct comedi_device` is the main controlling structure for a COMEDI device created by the COMEDI subsystem. It contains a member `spinlock` containing a spin-lock that is initialized by the COMEDI subsystem, but is reserved for use by a low-level driver attached to the COMEDI device (at least since commit 25436dc9d84f ("Staging: comedi: remove RT code")). Some COMEDI devices (those created on initialization of the COMEDI subsystem when the "comedi.comedi_num_legacy_minors" parameter is non-zero) can be attached to different low-level drivers over their lifetime using the `COMEDI_DEVCONFIG` ioctl command. This can result in inconsistent lock states being reported when there is a mismatch in the spin-lock locking levels used by each low-level driver to which the COMEDI device has been attached. Fix it by reinitializing `dev->spinlock` before calling the low-level driver's `attach` function pointer if `CONFIG_LOCKDEP` is enabled.

Scores

CVSS v3 5.5
EPSS 0.0001
EPSS Percentile 2.4%
Attack Vector LOCAL
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H

Details

Status published
Products (20)
Linux/Linux < 2.6.29
Linux/Linux 2.6.29
Linux/Linux 5.10.253 - 5.10.*
Linux/Linux 5.15.203 - 5.15.*
Linux/Linux 6.1.168 - 6.1.*
Linux/Linux 6.12.81 - 6.12.*
Linux/Linux 6.18.22 - 6.18.*
Linux/Linux 6.19.12 - 6.19.*
Linux/Linux 6.6.134 - 6.6.*
Linux/Linux 7.0
... and 10 more
Published May 08, 2026
Tracked Since May 08, 2026