[PATCH AUTOSEL 5.14 11/99] scsi: lpfc: Fix NULL ptr dereference with NPIV ports for RDF handling

[Sasha Levin]

From: James Smart <jsmart2021@xxxxxxxxx>

[ Upstream commit 2d338eb55b14ab9d245e8b1d982adecca8c4c613 ]

RDF ELS handling for NPIV ports may result in an incorrect NDLP reference
count.  In the event of a persistent link down, this may lead to premature
release of an NDLP structure and subsequent NULL ptr dereference panic.

Remove extraneous lpfc_nlp_put() call in NPIV port RDF processing.

Link: https://lore.kernel.org/r/20210707184351.67872-9-jsmart2021@xxxxxxxxx
Co-developed-by: Justin Tee <justin.tee@xxxxxxxxxxxx>
Signed-off-by: Justin Tee <justin.tee@xxxxxxxxxxxx>
Signed-off-by: James Smart <jsmart2021@xxxxxxxxx>
Signed-off-by: Martin K. Petersen <martin.petersen@xxxxxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
---
 drivers/scsi/lpfc/lpfc_els.c | 7 ++-----
 1 file changed, 2 insertions(+), 5 deletions(-)

diff --git a/drivers/scsi/lpfc/lpfc_els.c b/drivers/scsi/lpfc/lpfc_els.c
index b0c443a0cf92..b1ca6f8e5970 100644
--- a/drivers/scsi/lpfc/lpfc_els.c
+++ b/drivers/scsi/lpfc/lpfc_els.c
@@ -3413,7 +3413,6 @@ lpfc_issue_els_scr(struct lpfc_vport *vport, uint8_t retry)
 		return 1;
 	}
 
-	/* Keep the ndlp just in case RDF is being sent */
 	return 0;
 }
 
@@ -3657,11 +3656,9 @@ lpfc_issue_els_rdf(struct lpfc_vport *vport, uint8_t retry)
 		lpfc_enqueue_node(vport, ndlp);
 	}
 
-	/* RDF ELS is not required on an NPIV VN_Port.  */
-	if (vport->port_type == LPFC_NPIV_PORT) {
-		lpfc_nlp_put(ndlp);
+	/* RDF ELS is not required on an NPIV VN_Port. */
+	if (vport->port_type == LPFC_NPIV_PORT)
 		return -EACCES;
-	}
 
 	elsiocb = lpfc_prep_els_iocb(vport, 1, cmdsize, retry, ndlp,
 				     ndlp->nlp_DID, ELS_CMD_RDF);
-- 
2.30.2