[PATCH] scsi: lpfc: Fix crash on PCI hotplug remove path

["Guilherme G. Piccoli" <gpiccoli@linux.vnet.ibm.com>]

During a PCI hotplug remove event we could have a NULL pointer
dereference on lpfc_sli_abort_iocb(), if pring is NULL. This
patch adds a check for this case and is able to circumvent the
failure and continue the hotplug remove process with success.

This issue was introduced after the driver refactor made on
commit 895427bd012c ("scsi: lpfc: NVME Initiator: Base modifications").

Fixes: 895427bd012c ("scsi: lpfc: NVME Initiator: Base modifications")
Reported-by: Naresh Bannoth <nbannoth@in.ibm.com>
Signed-off-by: Guilherme G. Piccoli <gpiccoli@linux.vnet.ibm.com>
---
This patch was rebased against Martin's 4.12/scsi-fixes.

 drivers/scsi/lpfc/lpfc_sli.c | 10 +++++++---
 1 file changed, 7 insertions(+), 3 deletions(-)

diff --git a/drivers/scsi/lpfc/lpfc_sli.c b/drivers/scsi/lpfc/lpfc_sli.c
index d6b184839bc2..134c60a66fb8 100644
--- a/drivers/scsi/lpfc/lpfc_sli.c
+++ b/drivers/scsi/lpfc/lpfc_sli.c
@@ -11003,9 +11003,13 @@ lpfc_sli_abort_iocb(struct lpfc_vport *vport, struct lpfc_sli_ring *pring,
 
 		/* Setup callback routine and issue the command. */
 		abtsiocb->iocb_cmpl = lpfc_sli_abort_fcp_cmpl;
-		ret_val = lpfc_sli_issue_iocb(phba, pring->ringno,
-					      abtsiocb, 0);
-		if (ret_val == IOCB_ERROR) {
+
+		/* In PCI hotplug remove path, pring might be NULL */
+		if (pring)
+			ret_val = lpfc_sli_issue_iocb(phba, pring->ringno,
+						      abtsiocb, 0);
+
+		if (!pring || ret_val == IOCB_ERROR) {
 			lpfc_sli_release_iocbq(phba, abtsiocb);
 			errcnt++;
 			continue;
-- 
2.12.0.rc0