Linux vulnerability

What happened

In the Linux kernel, the following vulnerability has been resolved: firmware_loader: fix device reference leak in firmware_upload_register() firmware_upload_register() -> fw_create_instance() -> device_initialize() After fw_create_instance() succeeds, the lifetime of the embedded struct device is expected to be managed through the device core reference counting, since fw_create_instance() has already called device_initialize(). In firmware_upload_register(), if alloc_lookup_fw_priv() fails after fw_create_instance() succeeds, the code reaches free_fw_sysfs and frees fw_sysfs directly instead of releasing the device reference with put_device(). This may leave the reference count of the embedded struct device unbalanced, resulting in a refcount leak. The issue was identified by a static analysis tool I developed and confirmed by manual review. Fix this by using put_device(fw_dev) in the failure path and letting fw_dev_release() handle the final cleanup, instead of freeing the instance directly from the error path.

Affected versions

Linux: 97730bbb242cde22b7140acd202ffd88823886c9 through before 517676ec7dfca064e08f94007a4abd21969de0a0 (git); 97730bbb242cde22b7140acd202ffd88823886c9 through before 46d403da376a8b7c1187193294953816e1a8d7fe (git); 97730bbb242cde22b7140acd202ffd88823886c9 through before 2619b47a0c8114eef980a56ade7e3ef4b58eb384 (git); 97730bbb242cde22b7140acd202ffd88823886c9 through before 92f41769e5fd16bcd9ba97500d0517332e0a5b45 (git); 97730bbb242cde22b7140acd202ffd88823886c9 through before 15432f19562fdb9199cce6d9fc24db12c71ed574 (git); 97730bbb242cde22b7140acd202ffd88823886c9 through before 896df22ee57648b0c505bd76ddbc6b2341834696 (git); 5.19 Fixed: See vendor advisory.

Why it matters

Review the vendor advisory and exposure of the affected product to determine operational impact.

Detection & mitigation

• Apply vendor-provided updates or mitigations.
• Review affected product exposure and access logs.