CVE-2023-53568

A resource leak was found in the Linux kernel's s390 cryptographic device driver in the device creation path. When the dev_set_name function fails during creation of a zcrypt device node, the zcdn_create function returns an error without freeing the newly allocated device structure and associated resources. This creates a permanent memory leak, leading to resource exhaustion and denial of service.

The z/Architecture cryptographic device interface allows creation of additional device nodes for accessing crypto hardware. The zcdn_create function allocates a device structure and attempts to assign it a name using dev_set_name. If this naming operation fails—perhaps due to name collisions, memory allocation failures, or invalid characters—the function immediately returns an error code. At this point, the device structure has been allocated but never registered with the device core, so there's no automatic cleanup mechanism in place. The allocated memory, along with any other resources acquired during partial initialization, becomes orphaned. While dev_set_name failures are presumably rare in practice, any failure creates a leak that persists until system reboot. This is specific to s390 architecture systems with cryptographic hardware.

The CVSS score(s) listed for this vulnerability do not reflect the associated product's status, and are included for informational purposes to better understand the severity of this vulnerability.