CVE-2026-90284

About vulnerability

In the Linux kernel, the following vulnerability has been resolved:

firmware_loader: do not queue completed sysfs fallback requests

fw_load_sysfs_fallback() calls device_add() before adding the fw_priv to pending_fw_head. device_add() publishes the fallback loading interface, so a userspace helper which discovers the device by scanning sysfs can write 0 to the loading attribute and complete the request before it is queued as pending.

In that interleaving firmware_loading_store() calls fw_state_done() while pending_list still points to itself, so it cannot remove an entry from pending_fw_head. The subsequent unconditional list_add() then queues an already-completed fw_priv. Once the request is released, pending_fw_head can retain a pointer to freed memory and the next fallback request can fault while validating the list.

Only in-flight fallback requests need suspend or reboot abort handling. If the request is already DONE after device_add(), return success from the fallback path without sending another uevent, waiting again, or queueing it as pending. This preserves the invariant that pending_fw_head contains only active fallback requests.

Affected product:

AlmaLinux 9.2 ESU , CentOS 8.4 ELS , CentOS 8.5 ELS , CentOS Stream 8 ELS , Debian 11 ELS , TuxCare 9.6 ESU , TuxCare 9.8 ESU

Affected packages:

linux @ 5.10.270 (+6 more)

Live-patch status from KernelCare for each operating system.