From: Sudarsana Reddy Kalluru <sudarsana.kalluru@qlogic.com>
Date: Wed, 6 Jul 2016 10:51:29 +0000 (-0400)
Subject: bfa: Fix for crash when bfa_itnim is NULL
X-Git-Tag: v4.1.12-92~109^2
X-Git-Url: https://www.infradead.org/git/?a=commitdiff_plain;h=eb8bef99da3c75c97d3758b67e0b3faeb10f3bb5;p=users%2Fjedix%2Flinux-maple.git

bfa: Fix for crash when bfa_itnim is NULL

Orabug: 23950878

Fix a very corner case when the port gets disconnected and the BFA and
FCS layers clean up references to the IT nexus.  During this window if a
task management command is issued by the SCSI-ML and ends up referencing
a NULL itnim, it could lead to a crash.

Signed-off-by: Anil Gurumurthy <anil.gurumurthy@qlogic.com>
Tested-by: Sudarasana Kalluru <sudarsana.kalluru@qlogic.com>
Signed-off-by: Ethan Zhao <ethan.zhao@oracle.com>
---

diff --git a/drivers/scsi/bfa/bfad_im.c b/drivers/scsi/bfa/bfad_im.c
index f66ba723a95e..7db15423ee0e 100644
--- a/drivers/scsi/bfa/bfad_im.c
+++ b/drivers/scsi/bfa/bfad_im.c
@@ -272,6 +272,19 @@ bfad_im_target_reset_send(struct bfad_s *bfad, struct scsi_cmnd *cmnd,
 	cmnd->host_scribble = NULL;
 	cmnd->SCp.Status = 0;
 	bfa_itnim = bfa_fcs_itnim_get_halitn(&itnim->fcs_itnim);
+	/*
+	 * bfa_itnim can be NULL if the port gets disconnected and the bfa
+	 * and fcs layers have cleaned up their nexus with the targets and
+	 * the same has not been cleaned up by the shim
+	 */
+	if (bfa_itnim == NULL) {
+		bfa_tskim_free(tskim);
+		BFA_LOG(KERN_ERR, bfad, bfa_log_level,
+			"target reset, bfa_itnim is NULL\n");
+		rc = BFA_STATUS_FAILED;
+		goto out;
+	}
+
 	memset(&scsilun, 0, sizeof(scsilun));
 	bfa_tskim_start(tskim, bfa_itnim, scsilun,
 			    FCP_TM_TARGET_RESET, BFAD_TARGET_RESET_TMO);
@@ -327,6 +340,19 @@ bfad_im_reset_lun_handler(struct scsi_cmnd *cmnd)
 	cmnd->SCp.ptr = (char *)&wq;
 	cmnd->SCp.Status = 0;
 	bfa_itnim = bfa_fcs_itnim_get_halitn(&itnim->fcs_itnim);
+	/*
+	 * bfa_itnim can be NULL if the port gets disconnected and the bfa
+	 * and fcs layers have cleaned up their nexus with the targets and
+	 * the same has not been cleaned up by the shim
+	 */
+	if (bfa_itnim == NULL) {
+		bfa_tskim_free(tskim);
+		BFA_LOG(KERN_ERR, bfad, bfa_log_level,
+			"lun reset, bfa_itnim is NULL\n");
+		spin_unlock_irqrestore(&bfad->bfad_lock, flags);
+		rc = FAILED;
+		goto out;
+	}
 	int_to_scsilun(cmnd->device->lun, &scsilun);
 	bfa_tskim_start(tskim, bfa_itnim, scsilun,
 			    FCP_TM_LUN_RESET, BFAD_LUN_RESET_TMO);