High [CVE-2026-63889] Widen FPIN pname walker counter to u32

In the Linux kernel, the following vulnerability has been resolved: scsi: scsi_transport_fc: Widen FPIN pname walker counter to u32 An adjacent Fibre Channel fabric actor that can deliver an FPIN ELS frame to an lpfc or qla2xxx Linux initiator can trigger a non-return in the generic FC transport.

This is not a local userspace or IP network path; the attacker must be able to inject fabric traffic, for example as a compromised switch or fabric controller, or as a same-zone N_Port on a fabric that permits source spoofing.

The Link-Integrity and Peer-Congestion FPIN walkers used a u8 loop counter against the 32-bit on-wire pname_count field, and did not bound pname_count by the descriptor body already validated by the TLV walker. A pname_count of 256 therefore wraps the counter and keeps the loop condition true indefinitely.

Factor the shared pname_list[] walk into one helper, widen the counter to u32, and clamp pname_count against the entries that fit in the descriptor body before iterating.

An adjacent Fibre Channel fabric actor, such as a compromised switch or fabric controller, can send a specially crafted FPIN ELS (Fabric Performance Incentive Notification Extended Link Service) frame.

This malformed frame, specifically with a `pname_count` field that causes an integer overflow, can trigger an infinite loop, leading to a Denial of Service (DoS) in the affected system.