The Linux kernel's iommufd_fault_fops_read() function contained a flaw where a failure in copy_to_user() inside an inner loop caused only that loop to break, but the outer while loop would re-fetch the fault group and retry the failing operation indefinitely. This results in a spin loop consuming 100% CPU while holding a mutex, potentially causing a denial of service by CPU exhaustion and blocking other operations. The fix involves checking the return code after the inner loop and breaking the outer loop to prevent infinite retries.

This vulnerability can cause a denial of service condition by spinning the CPU at 100% while holding a mutex, potentially blocking other kernel operations. There is no indication of privilege escalation or data corruption. No known exploits are reported in the wild.

Patch status is not yet confirmed — check the vendor advisory for current remediation guidance. Monitor Linux kernel updates for an official fix addressing this issue. Until patched, affected systems may experience high CPU usage under specific fault conditions related to iommufd.