[SCSI] fnic: Kernel panic while running sh/nosh with max lun cfg

Kernel panics due to NULL lport while executing the log message because
of synchronization issues between libfc and scsi transport fc. Checking
for NULL pointers at the beginning of this routine would resolve the issue
from kernel panic point of view.

Signed-off-by: Sesidhar Baddel <sebaddel@cisco.com>
Signed-off-by: Hiral Patel <hiralpat@cisco.com>
Signed-off-by: James Bottomley <JBottomley@Parallels.com>

diff --git a/drivers/scsi/fnic/fnic_scsi.c b/drivers/scsi/fnic/fnic_scsi.c
index fb8413aa005f2ccf47291531487e74c4c68c9053..a876084ee12f4ea2380ddc7a46c38dd7f1c715f6 100644 (file)
--- a/drivers/scsi/fnic/fnic_scsi.c
+++ b/drivers/scsi/fnic/fnic_scsi.c
@@ -1416,12 +1416,29 @@ void fnic_terminate_rport_io(struct fc_rport *rport)
        unsigned long flags;
        struct scsi_cmnd *sc;
        struct scsi_lun fc_lun;
-       struct fc_rport_libfc_priv *rdata = rport->dd_data;
-       struct fc_lport *lport = rdata->local_port;
-       struct fnic *fnic = lport_priv(lport);
+       struct fc_rport_libfc_priv *rdata;
+       struct fc_lport *lport;
+       struct fnic *fnic;
        struct fc_rport *cmd_rport;
        enum fnic_ioreq_state old_ioreq_state;
 
+       if (!rport) {
+               printk(KERN_ERR "fnic_terminate_rport_io: rport is NULL\n");
+               return;
+       }
+       rdata = rport->dd_data;
+
+       if (!rdata) {
+               printk(KERN_ERR "fnic_terminate_rport_io: rdata is NULL\n");
+               return;
+       }
+       lport = rdata->local_port;
+
+       if (!lport) {
+               printk(KERN_ERR "fnic_terminate_rport_io: lport is NULL\n");
+               return;
+       }
+       fnic = lport_priv(lport);
        FNIC_SCSI_DBG(KERN_DEBUG,
                      fnic->lport->host, "fnic_terminate_rport_io called"
                      " wwpn 0x%llx, wwnn0x%llx, rport 0x%p, portid 0x%06x\n",