From: James Smart jsmart2021@gmail.com
[ Upstream commit 8dd1c125f7f838abad009b64bff5f0a11afe3cb6 ]
It is possible to call lpfc_issue_els_plogi() passing a did for which no matching ndlp is found. A call is then made to lpfc_prep_els_iocb() with a null pointer to a lpfc_nodelist structure resulting in a null pointer dereference.
Fix by returning an error status if no valid ndlp is found. Fix up comments regarding ndlp reference counting.
Link: https://lore.kernel.org/r/20210301171821.3427-10-jsmart2021@gmail.com Fixes: 4430f7fd09ec ("scsi: lpfc: Rework locations of ndlp reference taking") Co-developed-by: Dick Kennedy dick.kennedy@broadcom.com Signed-off-by: Dick Kennedy dick.kennedy@broadcom.com Signed-off-by: James Smart jsmart2021@gmail.com Signed-off-by: Martin K. Petersen martin.petersen@oracle.com Signed-off-by: Sasha Levin sashal@kernel.org --- drivers/scsi/lpfc/lpfc_els.c | 50 +++++++++++++++++------------------- 1 file changed, 24 insertions(+), 26 deletions(-)
diff --git a/drivers/scsi/lpfc/lpfc_els.c b/drivers/scsi/lpfc/lpfc_els.c index fd18ac2acc13..3dd22da3153f 100644 --- a/drivers/scsi/lpfc/lpfc_els.c +++ b/drivers/scsi/lpfc/lpfc_els.c @@ -1,7 +1,7 @@ /******************************************************************* * This file is part of the Emulex Linux Device Driver for * * Fibre Channel Host Bus Adapters. * - * Copyright (C) 2017-2020 Broadcom. All Rights Reserved. The term * + * Copyright (C) 2017-2021 Broadcom. All Rights Reserved. The term * * “Broadcom” refers to Broadcom Inc. and/or its subsidiaries. * * Copyright (C) 2004-2016 Emulex. All rights reserved. * * EMULEX and SLI are trademarks of Emulex. * @@ -2044,13 +2044,12 @@ out_freeiocb: * This routine issues a Port Login (PLOGI) command to a remote N_Port * (with the @did) for a @vport. Before issuing a PLOGI to a remote N_Port, * the ndlp with the remote N_Port DID must exist on the @vport's ndlp list. - * This routine constructs the proper feilds of the PLOGI IOCB and invokes + * This routine constructs the proper fields of the PLOGI IOCB and invokes * the lpfc_sli_issue_iocb() routine to send out PLOGI ELS command. * - * Note that, in lpfc_prep_els_iocb() routine, the reference count of ndlp - * will be incremented by 1 for holding the ndlp and the reference to ndlp - * will be stored into the context1 field of the IOCB for the completion - * callback function to the PLOGI ELS command. + * Note that the ndlp reference count will be incremented by 1 for holding + * the ndlp and the reference to ndlp will be stored into the context1 field + * of the IOCB for the completion callback function to the PLOGI ELS command. * * Return code * 0 - Successfully issued a plogi for @vport @@ -2068,29 +2067,28 @@ lpfc_issue_els_plogi(struct lpfc_vport *vport, uint32_t did, uint8_t retry) int ret;
ndlp = lpfc_findnode_did(vport, did); + if (!ndlp) + return 1;
- if (ndlp) { - /* Defer the processing of the issue PLOGI until after the - * outstanding UNREG_RPI mbox command completes, unless we - * are going offline. This logic does not apply for Fabric DIDs - */ - if ((ndlp->nlp_flag & NLP_UNREG_INP) && - ((ndlp->nlp_DID & Fabric_DID_MASK) != Fabric_DID_MASK) && - !(vport->fc_flag & FC_OFFLINE_MODE)) { - lpfc_printf_vlog(vport, KERN_INFO, LOG_DISCOVERY, - "4110 Issue PLOGI x%x deferred " - "on NPort x%x rpi x%x Data: x%px\n", - ndlp->nlp_defer_did, ndlp->nlp_DID, - ndlp->nlp_rpi, ndlp); - - /* We can only defer 1st PLOGI */ - if (ndlp->nlp_defer_did == NLP_EVT_NOTHING_PENDING) - ndlp->nlp_defer_did = did; - return 0; - } + /* Defer the processing of the issue PLOGI until after the + * outstanding UNREG_RPI mbox command completes, unless we + * are going offline. This logic does not apply for Fabric DIDs + */ + if ((ndlp->nlp_flag & NLP_UNREG_INP) && + ((ndlp->nlp_DID & Fabric_DID_MASK) != Fabric_DID_MASK) && + !(vport->fc_flag & FC_OFFLINE_MODE)) { + lpfc_printf_vlog(vport, KERN_INFO, LOG_DISCOVERY, + "4110 Issue PLOGI x%x deferred " + "on NPort x%x rpi x%x Data: x%px\n", + ndlp->nlp_defer_did, ndlp->nlp_DID, + ndlp->nlp_rpi, ndlp); + + /* We can only defer 1st PLOGI */ + if (ndlp->nlp_defer_did == NLP_EVT_NOTHING_PENDING) + ndlp->nlp_defer_did = did; + return 0; }
- /* If ndlp is not NULL, we will bump the reference count on it */ cmdsize = (sizeof(uint32_t) + sizeof(struct serv_parm)); elsiocb = lpfc_prep_els_iocb(vport, 1, cmdsize, retry, ndlp, did, ELS_CMD_PLOGI);