CVE-2026-74574
HighCVSS 7.8Exploitation Probability (EPSS)
Low risk2th percentile - higher than 2% of all known CVEs
Summary
In the Linux kernel, the dmaengine idxd driver has a cleanup issue after fdev setup failure in idxd_cdev_open(). The failed_dev_add and failed_dev_name paths drop the file-device reference while holding wq->wq_lock, which can deadlock if put_device() triggers idxd_file_dev_release() trying to reacquire the same lock. Additionally, these paths fall through to later ctx cleanup labels that may operate on freed context. The fix moves idxd_wq_get() before possible failure and unlocks wq->wq_lock before put_device().
Risk Assessment
The risk includes system deadlock or use-after-free in the idxd driver, potentially leading to system crash or unpredictable behavior. However, it requires local access and the ability to open cdev devices.
Recommendation
Update the Linux kernel to a version containing the fix for this issue. Also, monitor access to idxd devices and restrict it to trusted users.
Original NVD description (English source)
In the Linux kernel, the following vulnerability has been resolved: dmaengine: idxd: fix fdev setup failure cleanup in idxd_cdev_open() The failed_dev_add and failed_dev_name paths drop the file-device reference while wq->wq_lock is still held. If put_device(fdev) drops the last reference, idxd_file_dev_release() runs synchronously and tries to take wq->wq_lock again, deadlocking. Those paths also fall through into the later ctx cleanup labels even though idxd_file_dev_release() owns that cleanup and frees ctx. This can make idxd_xa_pasid_remove(ctx) and kfree(ctx) operate on a freed context. Move idxd_wq_get() before file-device setup can fail, since the release callback always calls idxd_wq_put(). Then unlock wq->wq_lock before put_device(fdev) and return directly from the file-device setup failure path, leaving ctx cleanup to the release callback.