From 4a0f4aff3ce5a3efdf674f3bc1ba7d2642fa55ea Mon Sep 17 00:00:00 2001 From: James Smart Date: Thu, 5 May 2022 20:55:13 -0700 Subject: scsi: lpfc: Use list_for_each_entry_safe() in rscn_recovery_check() In GID_PT mode with lpfc_ns_query=1, a race condition between iterating the vport->fc_nodes list in lpfc_rscn_recovery_check() and cleanup of an ndlp can trigger a crash while processing the RSCN of another initiator from the same zone. During iteration of the vport->fc_nodes list, an ndlp is cleaned up and released. lpfc_dequeue_node() is called from lpfc_cleanup_node() leading to a bad ndlp dereference in lpfc_rscn_recovery_check(). Change list_for_each_entry() to list_for_each_entry_safe() in lpfc_rscn_recovery_check() to protect against removal of an initiator ndlp, while walking the vport->fc_nodes list. Link: https://lore.kernel.org/r/20220506035519.50908-7-jsmart2021@gmail.com Co-developed-by: Justin Tee Signed-off-by: Justin Tee Signed-off-by: James Smart Signed-off-by: Martin K. Petersen --- drivers/scsi/lpfc/lpfc_els.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/drivers/scsi/lpfc/lpfc_els.c b/drivers/scsi/lpfc/lpfc_els.c index 583a287b2d0c..3671e0f8e041 100644 --- a/drivers/scsi/lpfc/lpfc_els.c +++ b/drivers/scsi/lpfc/lpfc_els.c @@ -7708,10 +7708,10 @@ return_did_out: static int lpfc_rscn_recovery_check(struct lpfc_vport *vport) { - struct lpfc_nodelist *ndlp = NULL; + struct lpfc_nodelist *ndlp = NULL, *n; /* Move all affected nodes by pending RSCNs to NPR state. */ - list_for_each_entry(ndlp, &vport->fc_nodes, nlp_listp) { + list_for_each_entry_safe(ndlp, n, &vport->fc_nodes, nlp_listp) { if ((ndlp->nlp_state == NLP_STE_UNUSED_NODE) || !lpfc_rscn_payload_check(vport, ndlp->nlp_DID)) continue; -- cgit v1.2.3