CVE-2026-43340 PUBLISHED

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

Assigner: Linux
Reserved: 01.05.2026 Published: 08.05.2026 Updated: 08.05.2026

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.

Product Status

Vendor Linux
Product Linux
Versions Default: unaffected
  • affected from ed9eccbe8970f6eedc1b978c157caf1251a896d4 to 3181c34b415c5464be9d34bff3e43ef63b747039 (excl.)
  • affected from ed9eccbe8970f6eedc1b978c157caf1251a896d4 to 2b1f49e4fdff3ef0f8e9158bbb5b149e06287560 (excl.)
  • affected from ed9eccbe8970f6eedc1b978c157caf1251a896d4 to 4d5ffe524903a30e2e0da7d16841a56bec2de55c (excl.)
  • affected from ed9eccbe8970f6eedc1b978c157caf1251a896d4 to c01bcc67a9a692d65508ebd480405b5e77d562b7 (excl.)
  • affected from ed9eccbe8970f6eedc1b978c157caf1251a896d4 to 430291d8f3884f57ae0057049b0ca291453e29e1 (excl.)
  • affected from ed9eccbe8970f6eedc1b978c157caf1251a896d4 to b89c026227712c367950bbae055a5b31073d3b30 (excl.)
  • affected from ed9eccbe8970f6eedc1b978c157caf1251a896d4 to 83134a7a176ce5b4b19b6edecf4360e8d98d1a5a (excl.)
  • affected from ed9eccbe8970f6eedc1b978c157caf1251a896d4 to 4b9a9a6d71e3e252032f959fb3895a33acb5865c (excl.)
Vendor Linux
Product Linux
Versions Default: affected
  • Version 2.6.29 is affected
  • unaffected from 0 to 2.6.29 (excl.)
  • unaffected from 5.10.253 to 5.10.* (incl.)
  • unaffected from 5.15.203 to 5.15.* (incl.)
  • unaffected from 6.1.168 to 6.1.* (incl.)
  • unaffected from 6.6.134 to 6.6.* (incl.)
  • unaffected from 6.12.81 to 6.12.* (incl.)
  • unaffected from 6.18.22 to 6.18.* (incl.)
  • unaffected from 6.19.12 to 6.19.* (incl.)
  • unaffected from 7.0 to * (incl.)

References