On 5/20/26 15:30, Michael Bommarito wrote:
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. Fixes: 3dcfe0de5a97 ("scsi: fc: Parse FPIN packets and update statistics") Cc: [email protected] Assisted-by: Claude:claude-opus-4-7 Signed-off-by: Michael Bommarito <[email protected]> --- Changes in v4: - Use min() rather than min_t(u32, ...) for the pname_count clamp and fold away the temporary max_count variable, as David Laight suggested. Changes in v3: - State the fabric-adjacent threat model explicitly in the commit message and clarify that this is not local userspace or IP-network reachable. - Use min_t(u32, ...) for the pname_count clamp, as Christoph suggested. - Use FC_TLV_DESC_LENGTH_FROM_SZ() instead of open-coding the descriptor body length calculation. - Factor the duplicate LI and peer-congestion pname walker into a common helper while preserving the LI-only host-stat update. Changes in v2: - Drop the redundant cover letter shipped with v1. A single-patch send does not need one, and the v1 cover carried stale draft markers. drivers/scsi/scsi_transport_fc.c | 77 +++++++++++++++++--------------- 1 file changed, 41 insertions(+), 36 deletions(-)
Reviewed-by: Hannes Reinecke <[email protected]> Cheers, Hannes -- Dr. Hannes Reinecke Kernel Storage Architect [email protected] +49 911 74053 688 SUSE Software Solutions GmbH, Frankenstr. 146, 90461 Nürnberg HRB 36809 (AG Nürnberg), GF: I. Totev, A. McDonald, W. Knoblich
