A race condition between the context of devloss timeout handler
and I/O completion caused devloss timeout handler de-referencing
pointer that had been released.

Added the check in lpfc_sli_validate_fcp_iocb() on
LPFC_IO_ON_TXCMPLQ to capture the race condition of I/O completion
and devloss timeout handler attemption for aborting the I/O. Also,
added check on lpfc_cmd->rdata pointer before de-referenceing
lpfc_cmd->rdata->pnode.

Also, added protection in lpfc_sli_abort_iocb() routine on driver
performed FCP I/O FLUSHING already under way before proceeding
to aborting I/Os.

Signed-off-by: Dick Kennedy <dick.kenn...@broadcom.com>
Signed-off-by: James Smart <james.sm...@broadcom.com>
---
 drivers/scsi/lpfc/lpfc_scsi.c |  5 +++++
 drivers/scsi/lpfc/lpfc_sli.c  | 13 +++++++++----
 2 files changed, 14 insertions(+), 4 deletions(-)

diff --git a/drivers/scsi/lpfc/lpfc_scsi.c b/drivers/scsi/lpfc/lpfc_scsi.c
index c31c43f43553..5e4cad6a531a 100644
--- a/drivers/scsi/lpfc/lpfc_scsi.c
+++ b/drivers/scsi/lpfc/lpfc_scsi.c
@@ -4538,6 +4538,11 @@ lpfc_queuecommand(struct Scsi_Host *shost, struct 
scsi_cmnd *cmnd)
        int err;
 
        rdata = lpfc_rport_data_from_scsi_device(cmnd->device);
+
+       /* sanity check on references */
+       if (unlikely(!rdata) || unlikely(!rport))
+               goto out_fail_command;
+
        err = fc_remote_port_chkready(rport);
        if (err) {
                cmnd->result = err;
diff --git a/drivers/scsi/lpfc/lpfc_sli.c b/drivers/scsi/lpfc/lpfc_sli.c
index 3299913876ce..d4078fda11a5 100644
--- a/drivers/scsi/lpfc/lpfc_sli.c
+++ b/drivers/scsi/lpfc/lpfc_sli.c
@@ -11097,10 +11097,11 @@ lpfc_sli_validate_fcp_iocb(struct lpfc_iocbq *iocbq, 
struct lpfc_vport *vport,
        struct lpfc_scsi_buf *lpfc_cmd;
        int rc = 1;
 
-       if (!(iocbq->iocb_flag &  LPFC_IO_FCP))
+       if (iocbq->vport != vport)
                return rc;
 
-       if (iocbq->vport != vport)
+       if (!(iocbq->iocb_flag &  LPFC_IO_FCP) ||
+           !(iocbq->iocb_flag & LPFC_IO_ON_TXCMPLQ))
                return rc;
 
        lpfc_cmd = container_of(iocbq, struct lpfc_scsi_buf, cur_iocbq);
@@ -11110,13 +11111,13 @@ lpfc_sli_validate_fcp_iocb(struct lpfc_iocbq *iocbq, 
struct lpfc_vport *vport,
 
        switch (ctx_cmd) {
        case LPFC_CTX_LUN:
-               if ((lpfc_cmd->rdata->pnode) &&
+               if ((lpfc_cmd->rdata) && (lpfc_cmd->rdata->pnode) &&
                    (lpfc_cmd->rdata->pnode->nlp_sid == tgt_id) &&
                    (scsilun_to_int(&lpfc_cmd->fcp_cmnd->fcp_lun) == lun_id))
                        rc = 0;
                break;
        case LPFC_CTX_TGT:
-               if ((lpfc_cmd->rdata->pnode) &&
+               if ((lpfc_cmd->rdata) && (lpfc_cmd->rdata->pnode) &&
                    (lpfc_cmd->rdata->pnode->nlp_sid == tgt_id))
                        rc = 0;
                break;
@@ -11231,6 +11232,10 @@ lpfc_sli_abort_iocb(struct lpfc_vport *vport, struct 
lpfc_sli_ring *pring,
        int errcnt = 0, ret_val = 0;
        int i;
 
+       /* all I/Os are in process of being flushed */
+       if (phba->hba_flag & HBA_FCP_IOQ_FLUSH)
+               return errcnt;
+
        for (i = 1; i <= phba->sli.last_iotag; i++) {
                iocbq = phba->sli.iocbq_lookup[i];
 
-- 
2.13.1

Reply via email to