CVEvulnerability
CVE-2026-64474
- Status
- Received
- Published
- 2026-07-25
- Last modified
- 2026-08-17
- Assigner
- 416baaa9-dc9f-4396-8d5f-8c081fb06d67
Description
In the Linux kernel, the following vulnerability has been resolved:
vfio: prevent infinite loop in vfio_mig_get_next_state() on blocked arc
vfio_mig_get_next_state() walks vfio_from_fsm_table[] one step at a time,
looping to skip optional states the device does not support until
*next_fsm is supported. A blocked transition is encoded as
VFIO_DEVICE_STATE_ERROR, which the trailing return reports as -EINVAL.
The skip loop does not account for the ERROR sentinel.
state_flags_table[ERROR] is ~0U and vfio_from_fsm_table[ERROR][*] is
ERROR, so once *next_fsm becomes ERROR the loop condition stays true and
*next_fsm never changes. The blocked arcs STOP_COPY -> PRE_COPY and
STOP_COPY -> PRE_COPY_P2P map to ERROR yet pass the support check on a
precopy-capable device, causing the loop to spin forever while holding
the driver state mutex. This can result in a soft lockup, and a panic
with softlockup_panic set.
Terminate the skip loop on the ERROR sentinel so a blocked transition
falls through to the existing return and reports -EINVAL.
References
- https://git.kernel.org/stable/c/7f2d6b31089e48db4653df832c9a6afdde9a1c29 git.kernel.org
- https://git.kernel.org/stable/c/8e872c07e40d51a66dee7b280a23a460a2e1e3fa git.kernel.org
- https://git.kernel.org/stable/c/a26b499b757cfc8bbff1088bb1b844639e250893 git.kernel.org
- https://git.kernel.org/stable/c/a3a8afa2f6e7f0dc266d08f02be3f3054241ba47 git.kernel.org
- https://git.kernel.org/stable/c/ed7d5599e6c398da74845767cd1e6a8370a160fc git.kernel.org